vol.

43

BOOK & CDｰROM
独立行政法人理化学研究所 仁科加速器研究センター

RIKEN Nishina Center for Accelerator-Based Science

RIKEN Accelerator Progress Report
vol.

43

BOOK & CDｰROM

独立行政法人理化学研究所 仁科加速器研究センター
RIKEN Nishina Center for Accelerator-Based Science
Wako, Saitama, 351-0198 JAPANChairperson of the Editorial Committee

O. Kamigaito   Editorial Committee

H. Okuno
S. Nishimura
H. Haba
M. WadaS. Yokkaichi
T. TadaT. AbeK. Yazaki
T. Ichihara

K. Yoneda
K. Morimoto
A. KohamaN. Inabe
Y. Kobayashi
T. Kambara
Y. Uwamino
K. Ishida
T. Gunji

Y. SakataY. SatoAll rights reserved. This report or any part thereof may not be reproduced in any
from (including photostatic or microfilm form) without written permission from thepublisher.
All reports are written on authors’ responsibility and thus the editors are not liable
for the contents of the report.

GRAVURES & HIGHLIGHTS OF THE YEAR
M. Wakasugi

et al. ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・

iConstruction of electron accelerators
G. Watanabe et al. ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・

iii

Formation of Nuclear “Pasta” in Supernovae
I. Kishimoto and T. Takahashi ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・

v

Numerical evaluation of gauge invariants for a-gauge solutions inopen string field theory
K. Takagi et al. ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ ・・・・・・・・

vii

Localization of γH2AX Fluorescence along Tracks of Argon Beams
M. Asai et al. ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・
α-fine structure spectroscopy for257

Lr and

259

ix

Lr

P. Doornenbal et al. ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・

x32

In-beam gamma-ray Spectroscopy of Ne
K. Sekiguchi et al. ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・

xi

Complete Set of Deuteron Analyzing Powers for dp Elastic
Scattering at 250 MeV/nucleon and Three-Nucleon Forces
K. Yoshida. ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・

xii

Negative-parity excitations unique in deformed neutron-rich nuclei
close to the drip line
H. Nemura for HAL QCD Collaboration, ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・

xiii

Lattice QCD study of Lambda N interaction
K. Karatsu from the PHENIX Collaboration ・・・・・・・・・・・・・・・・・・・・・・・・・・・・

xiv

W- Boson Production in Polarized p+p Collision at sqrt(s) = 500GeV
Y. Sato et al. ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・

xv

Application of a Pair of Solenoid Magnets in Beam Transport Line・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・

xvii

Measurement of charge-state distribution of uranium and xenon
beams with a gas charge stripper
T. Suzuki et al. ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・

xix

H. Kuboki

et al.

Pressure-induced new magnetic phase in Tl(Cu0:985Mg0:015)Cl3
probed by muon spin rotation
K. Yokoyama, K. Nagamine et al.

・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・

Characterization of Spin-Dpendent Response of Negative Muonium (Mu-)
to Laser Induced Polarized Electrons in n-type GaAs under Zero FieldxxSelection process of gravures and highlights
Gravures and highlights will be selected in two-steps process. In the first step, referee will
recommend manuscript for gravure or highlight. With the above recommendation, the editors
will then give secondary recommendation.
After the following 1 and 2 are comprehensively considered, the editor-in-chief will draft amanuscript idea which will be thoroughly discussed by the editors for the final decision:
1. Approval based on the editor's judgment as an expert/non-expert in the field ( there byagreeing with the referee's recommendation )2. Additional recommendation based on the editor's expertise.

 RIKEN Accel. Prog. Rep. 43 (2010)

Construction of electron accelerators
M. Wakasugi, Y. Miyashita, H. Takehara,1 H. Takahashi,*2 M. Togasaki,2 T. Hori, M. Hara, K. Kurita*2 and T. Suda
An electron accelerators system, which is consists of a
microtron type of accelerator and a synchrotron storage ring,is now under construction in RIKEN Nishina Center aiming
for electron scattering experiments for short-lived unstable
nuclei using the SCRIT technique1,2). These accelerators arereuse of the synchrotron storage ring (AURORA-2S) 3) andthe racetrack microtron (RTM) 4), which were developed
and operated at Sumitomo Heavy Industry Co. Ltd.
These electron accelerators have been transferred from
Sumitomo Heavy Industry Co. Ltd. in last summer. In thefirst half of this year, infrastructures required for theaccelerator system and the experimental system have been
constructed in the E21 experimental room at the RIBF.
Reconstruction of the accelerators has been started at
middle of September in this year. Since the AURORA-2S
has been developed as the most compact synchrotron lightsource and there is no free straight section, it was
remodeled to the AURORA-2D5) type of the ring, which
provides 2.15-m length straight sections for insertion of the
SCRIT device. This revised storage ring is renamed to be
SR2 (SCRIT-equipped Riken Storage Ring).

Layout of the accelerators is shown in Fig. 1. The RTM isplaced in the small room surrounded by 2-m thick concrete
wall for radiation shield. The RTM is connected to the SR2
placed outside the shielded room with 16-m long beamtransport line (eBT) consisting of four quadrupole doublets
and a 77.8-degrees bending magnet.
Specifications of the RTM and the SR2 is shown in Table
1 and 2, respectively. The RTM has a S-band standing wave
type of linac providing the energy gain of 6 MeV, which isdriven by a 2-MW (peak) pulse klystron. The electron beam
injected from the electron gun with the energy of 80 keV
passes trough the linac by 25 times and the final energy is
150 MeV. The RTM has another function as a driver for RI
production via photo-fissions of Uranium target put in theion source of the ISOL system.
Table 1. RTM specifications
Beam energy(MeV)
Injection energy(keV)Peak current(mA)
Pulse width(µs)
Repetition rate
(Hz)
Energy resolution(%)
Emittance(πmm mrad)
Number of turns
RF frequency(MHz)
RF peak power
MW
Energy gain
MeV/turn

150
80
2-10
0.2-2
100 (max.)±0.1 (1σ)
0.5
25
2856
2 (beam loading)
6

Table 2. SR2 specifications
Circumference(m)Beam energy(MeV)
Magnetic field(T)
Bending radius(m)
Betatron tune
(h/v)
RF frequency(MHz)
Harmonic number
RF power(kW)
RF voltage(kV)Stored current(mA)
Beam emittance(πmm mrad)

21.95
150-700
0.6-2.7
0.87
1.72 / 1.84
191.2441430
220
300 (expected)
0.4

The SR2 is a racetrack type of storage ring. The lattice
structure is defined by two 180-degree-bending magnets
and four quadrupole doublets. Electron beam from the RTM
is injected into the SR2 through a 90-degree inflection pulse
magnet. The SR2 accepts 150-MeV electron beam and it
can accelerate the beam up to 700 MeV by lamping up themagnetic field. The maximum magnetic field in the180-degrees bending magnet is 2.7 T. The RF frequency isFig. 1 Layout of electron accelerators. The RTM is placed
in shielded room and the SR2 is outside. The SCRIT
devices will be installed in a straight section of the SR2, andthe ions of unstable nuclei will be supplied by ISOL system,
which is planed to be constructed in the shielded room.

-i-191.244 MHz and the power of 30 kW in the cavity isrequired at the energy of 700 MeV.
Mechanical assembly of both accelerators has been
almost completed by the end of 2009. Figure 2 shows
photographs of the RTM and the SR2. Each component in
the SR2 and the operating system are now undergoing
testing. Commissioning of the RTM was performed at theend of 2009. We succeeded in acceleration of the electron
beam up to 150 MeV and extraction of the beam from the
RTM at Dec. 24 in 2009. Figure 3 (A) shows synchrotron
radiation coming out the RTM during the acceleration.
Light points corresponding to every electron beam orbits in
the RTM were observed. Because only the beam gettingenergy gain of 6 MeV from the linac in every turn cancirculate along the design orbit which is well defined by themagnetic field and small beam tubes, we could confirm theacceleration up to 150 MeV by counting the number of thelight points. Accelerated electron beam was extracted fromthe RTM, and it was observed by a screen monitor as shownin Fig. 3 (B). The peak current of the first beam from the
RTM was 1.5 mA, the pulse width was 1 µs, and therepletion rate was 2 Hz.

4 shows a photograph of the SCRIT device. It consists ofthree electrodes providing trapping potential, ion injectionand extraction channels, scraper-type beam position
monitors, and nondestructive button-electrode-type beam
position monitors. These components will be put in a 2-mlong vacuum chamber and installed at the straight section of
the SR2. Since this is a high-impedance device, carful
tuning procedure of the SR2 after the installation will be
required for stable accumulation of high-current electron
beams.

(A)(B)

Fig. 3. Photographs of (A) the synchrotron radiations
coming out from the RTM, and (B) the beam spot on thescreen monitor at the exit of the RTM.

Fig. 4. Photograph of the SCRIT device, which will be
installed in the SR2.
The SR2 will be operated not only for the SCRIT
experiment but also for utilizing the synchrotron radiations.
We will provide several light beam ports around thebending magnet. The energy of accumulated electron beams
for synchrotron radiation use is required to be 700 MeV,
while that will be 300 MeV or less for the SCRIT
experiment. We will establish plural operation patterns for a
responsibility to the users. Operation for synchrotron light
use will be ready in 2011.

References
Fig. 2. Photographs of the RTM (a) and the SR2 (b).
The SR2 will be commissioned within this fiscal year, andwe will spend more half years for tuning of theses machines.
In next fiscal year, the SCRIT system will be installed into
the SR2 after making the SR2 ready for experiments. Figure- ii -

1) M. Wakasugi et al., Phys. Rev. Lett. 100, 164801 (2008).
2) T. Suda et al., Phys. Rev. Lett. 102, 102501 (2009).
3) H. Miyade et al., Proc. EPAC98, Stockholm, (1998) p.2413.
4) T. Hori et al., Proc. PAC91, San Francisco, (1991) p.2877.
5) T. Takayama et al., Proc., EPAC96, Barcelona, (1996) p.709.

RIKEN Accel. Prog. Rep. 43 (2010)

Formation of Nuclear “Pasta” in Supernovae†
G. Watanabe∗1,∗2 , H. Sonoda,∗1,∗3 T. Maruyama,∗4 K. Sato,∗3,∗5 K. Yasuoka,∗6 and T. Ebisuzaki∗1[Supernova explosions, nuclear pasta phases, quantum moelcular dynamics]
The mechanism of collapse driven supernova explosions2) has been one of the central mysteries in astrophysics for more than 40 years3) . Matter in supernova cores is also yet to be understood and these issues
are closely connected. In collapsing supernova cores,
while matter consists of bcc lattice of spherical nuclei
at lower densities, “pasta” nuclei such as “spaghetti”like columnar nuclei and “lasagna”-like planar nuclei,
etc. are expected to be formed4,5) at higher densities
and they amount to more than 20% of the total massof the cores just before the bounce6) . Since neutrino
scattering property is very different between pasta nuclei and spherical ones7,8) , pasta phases can have asignificant influence on the dynamics of explosions.
However, most of the previous works about the pasta
phases are based on assuming the shape of nuclei
within a static framework. Therefore, a fundamental
problem whether or not the pasta phases are actuallyformed in collapsing cores has been still unclear. Since
formation of the pasta phases from spherical nuclei
is accompanied by dynamical and drastic changes of
the nuclear structure, an ab-initio approach is called
for. In the present work, using a dynamical framework called quantum molecular dynamics (QMD)9,10) ,we have solved this question by demonstrating that alattice of rod-like nuclei is formed from a bcc latticeby compression. Our result establishes that the pasta
phases can be formed in collapsing supernova cores.
A generally accepted conjecture11) based on the
Bohr-Wheeler condition for fission predicts that theformation of the pasta phases are triggered by the fission instability with respect to the quadrupolar deformation of spherical nuclei. Then all the nuclei aresupposed to elongate in the same direction and theyjoin up to form straight rod-like nuclei. The essential
physics of the fission instability is that, at higher densities, the effect of the Coulomb repulsion between protons in nuclei, which tends to make a nucleus deform,
becomes dominant over the effect of the surface tensionof the nuclei, which favors a spherical nucleus. However, the Bohr-Wheeler condition is derived for isolated nuclei, and actually, several works have pointed
†

∗1
∗2
∗3
∗4
∗5
∗6

Condensed from Ref.1) . In this work, we used MDGRAPE2 and -3 of the RIKEN Super Combined Cluster System.
This work is featured by the APS Physical Review Focus
Synopsis and by RIKEN Research (issue of January 2010).
RIKEN
Asia Pacific Center for Theoretical Physics (APCTP)
Department of Physics, University of Tokyo
ASRC, Japan Atomic Energy Agency
IPMU, University of Tokyo
Department of Mechanical Engineering, Keio University- iii -(a) 0.150ρ0 L=51.23 fm

t=0 fm/c(d) 0.245ρ0 L=43.50 fm

t=58220 fm/c(g) 0.275ρ0 L=41.86 fm

t=76570 fm/c(b) 0.231ρ0 L=44.39 fm(c) 0.243ρ0 L=43.62 fm

t=49410 fm/c(e) 0.247ρ0 L=43.36 fm

t=57080 fm/c(f) 0.249ρ0 L=43.28 fm

t=59750 fm/c(h-1) 0.275ρ0 L=41.86 fm (h-2)

t=191210 fm/c

t=60510 fm/c
Top view

line of sight

Fig. 1. Snapshots of the transition process from the bcc
lattice of spherical nuclei to the pasta phase with rodlike nuclei obtained by our QMD simulation. The red
particles show protons and the green ones neutrons.
In panels (a)-(g) and (h-1), nucleons in a limited region [surrounded by the dotted lines in panel (h-2)] areshown for visibility. The vertices of the dashed lines
in panels (a) and (d) show the equilibrium positions of
nuclei in the bcc lattice and their positions in the direction of the line of sight are indicated by the size ofthe circles: vertices with a large circle, with a small circle, and those without a circle are in the first, second,
and third lattice plane, respectively. The solid lines inpanel (d) represent the direction of the two elongatednuclei: they take zigzag configuration. This figure istaken from Ref.1) .

out that the background electrons, which have been
ignored in the above prediction, suppress the effect of
the Coulomb repulsion between protons in nuclei andthe fission barrier never vanishes in the relevant density region12,13) . This puzzle has been also solved byour present work.
In Fig. 1, we show the snapshots of the formation
process of the pasta phase in adiabatic compression.
Here, we start from initial condition at the density
ρ = 0.15ρ0 and the temperature T = 0.25 MeV [Fig.
1(a)]. At ρ  0.243ρ0 [Fig. 1(c)], the first pair of twonearest-neighbor nuclei start to touch and fuse (dot-Fig. 2. Snapshots of the simulation of compression at T <0.01 MeV using the simplified model. The red particles
show the centers of mass of nuclei and the nuclei within(0)
the distance less than 0.89rnn are connected by a blueline. Nuclei and connections within only two latticeplanes normal to the line of sight are shown. This figure
is taken from Ref.1) .

ted circle), and then form an elongated nucleus. After
multiple pairs of nuclei become such elongated nuclei,
we observe zigzag structure [Fig. 1(d)]. Then theseelongated nuclei stick together [see Figs. 1(e) and (f)],and all the nuclei fuse to form rod-like nuclei as shownin Fig. 1(g). Finally, we obtain a triangular lattice of
rod-like nuclei after relaxation [Figs. 1(h-1) and (h-2)].
Note that before nuclei deform to be elongated dueto the fission instability, they stick together keeping
their spherical shape [see Fig. 1(c)]. Our simulationshows that the pasta phase can be formed even though
there is no fission instability. Besides, in the middleof the transition process, pair of spherical nuclei getcloser to fuse in a way such that the resulting elongatednuclei take a zigzag configuration and then they further
connect to form wavy rod-like nuclei. This process
is very different from the above mentioned generally
accepted scenario.
We also examine the zigzag structure in the QMD
simulation for a larger system using a simplified model.
Since nuclei start to connect before they are deformed,
it is reasonable to treat a nucleus as a sphere and incorporate only its center-of-mass degree of freedom.
On the other hand, when the nearest neighbor nuclei are so close that the tails of their density profile overlap with each other, net attractive interaction
between these nuclei starts to act. We thus consider
the following minimal model in which each nucleus is- iv -

treated as a point charged particle interacting throughthe Coulomb potential and the potential of the WoodsSaxon form which describes the finite size of nuclei andmodels the internuclear attraction.
With this model, we perform compression of a bcc
lattice with 128 nuclei 208 Pb, which corresponds to 8
times larger system than that of the QMD simulation.
We show the snapshots of this simulation in Fig. 2.
In the situation of Fig. 2(b), the first pair of nuclei
starts to get closer and then we stop the compression
and relax the system. We observe pairings in a zigzag
configuration around the first pair [Fig. 2(c)] and finally we obtain a zigzag structure [Fig. 2(d)]. This
result shows that the internuclear attraction leads tothe spontaneous breaking of the bcc lattice and supports the formation of the zigzag structure observed in
the QMD simulation.
In summary, we have shown that the pasta phase canbe formed by the compression of matter in collapsingsupernova cores. We have found that the formation
process is very different from a generally accepted scenario based on the fission instability. Our QMD simulation has shown that a pair of the nearest neighbor nuclei start to connect before they deform due to the fission instability. This spontaneous breaking of the bcc
structure is due to an internuclear attraction causedby the overlap of the tails of nucleon distribution ofneighboring nuclei. We have also discovered that, inthe transition process, the system takes a zigzag configuration of elongated nuclei, which are formed by afusion of original two spherical nuclei.
References
1) G. Watanabe, H. Sonoda, T. Maruyama, K. Sato,K. Yasuoka, and T. Ebisuzaki, Phys. Rev. Lett. 103,
121101 (2009).
2) H. A. Bethe, Rev. Mod. Phys. 62, 801 (1990).
3) S. A. Colgate and R. H. White, Astrophys. J. 143, 626(1966).
4) D. G. Ravenhall, C. J. Pethick and J. R. Wilson, Phys.
Rev. Lett. 50, 2066 (1983).
5) M. Hashimoto, H. Seki, and M. Yamada, Prog. Theor.
Phys. 71, 320 (1984).
6) H. Sonoda, G. Watanabe, K. Sato, T. Takiwaki, K. Yasuoka, and T. Ebisuzaki, Phys. Rev. C 75, 042801(R)(2007).
7) G. Watanabe, K. Iida, and K. Sato, Nucl. Phys. A687,
512 (2001).
8) C. J. Horowitz, M. A. Pérez-Garcı́a, and J.
Piekarewicz, Phys. Rev. C 69, 045804 (2004).
9) J. Aichelin, Phys. Rep. 202, 233 (1991).
10) T. Maruyama, K. Niita, K. Oyamatsu, T. Maruyama,
S. Chiba, and A. Iwamoto, Phys. Rev. C 57, 655(1998).
11) C. J. Pethick and D. G. Ravenhall, Annu. Rev. Nucl.
Part. Sci. 45 (1995) 429.
12) S. Brandt, Master thesis, Copenhagen Univ. (1985).
13) T. J. Bürvenich, I. N. Mishustin, and W. Greiner,
Phys. Rev. C 76 (2007), 034310.

RIKEN Accel. Prog. Rep. 43 (2010)

Numerical evaluation of gauge invariants for a-gauge solutions inopen string ﬁeld theory†
I. Kishimoto and T. Takahashi∗1[Nonperturbative techniques, string ﬁeld theory, D branes]
We evaluate the gauge invariants, action and gauge
invariant overlap, for numerical solutions for tachyon
condensation in the a-gauge in cubic bosonic open
string ﬁeld theory. With an increase in the truncationlevel, the values of the gauge invariants for various values of a approach those of Schnabl analytic solution1)
for tachyon condensation. This is consistent with the
expectation that these numerical solutions are gauge
equivalent to the Schnabl analytic solution.
The a-gauge given by Asano and Kato2) is a consistent linear gauge and includes a real parameter a.
It can be regarded as an extension of the conventional
Siegel gauge. It can be precisely expressed as(b0 M + ab0 c0 Q̃)Ψ = 0

OGF = b0 c0 Q̃

QΨ(n) ϕ = QB ϕ + Ψ(n) ∗ ϕ − (−1)|ϕ| ϕ ∗ Ψ(n)(8)

for any string ﬁeld ϕ. If the conﬁguration Ψ(n) obtained by the above iterations converges in the limitn → ∞, a projected part of the equation of motion
given byc0 b0 (QB Φ(∞) + Φ(∞) ∗ Φ(∞) ) = 0,(9)

is satisﬁed in the a-gauge. In order to conﬁrm thecomplete equation of motion for the converged conﬁguration Ψ(∞) , we have numerically evaluated the remaining part that is given by

for a classical open string ﬁeld Ψ. Here, the operators
M and Q̃ can be expressed by expanding the KatoOgawa BRST operator QB with respect to ghost zeromodes (i.e., b0 and c0 ) asb0 c0 (QB Φ(∞) + Φ(∞) ∗ Φ(∞) ) = 0.

(10)

For each numerical solution Φ(∞) obtained in thea-gauge, we computed the values of the action andthe gauge invariant overlap. The results for the action
S(Ψ), where
)
(
1 1
1
S(Ψ) = − 2⟨Ψ, QB Ψ⟩ + ⟨Ψ, Ψ ∗ Ψ⟩ ,
(11)
g
2
3

(2)

By expanding the massless part of the action of the freestring ﬁeld theory in the a-gauge, one can ﬁnd that theparameter a corresponds to the gauge parameter α ofthe ordinary gauge theory; the relationship between
them is given by α = (a − 1)−2 .
We construct numerical solutions3) for tachyon condensation to the equation of motion of the cubic string
ﬁeld theory
QB Ψ + Ψ ∗ Ψ = 0(7)Further, QΨ(n) is an operator that can be expressed as(1)

QB = Q̃ + c0 L0 + b0 M.

(a = ∞).

in the (L, 3L) truncation are plotted in Fig. 1. The(3)

in the a-gauge using an iterative algorithm as follows. Using the initial conﬁguration Ψ(0) , which isthe non-trivial solution in the lowest-level approximation, string ﬁelds Ψ(1) , Ψ(2) , Ψ(3) , · · · can be computedby solving the following linear equations for Ψ(n+1)(n = 0, 1, 2, · · · ) in (L, 2L) or (L, 3L) truncation:
OGF Ψ(n+1) = 0,

c0 b0 (QΨ(n) Ψ(n+1) − Ψ(n) ∗ Ψ(n) ) = 0.

(4)
Fig. 1. Plots of the action for various a-gauge solutions Ψain the (L, 3L) truncation. The horizontal axis denotes
the value of a and the vertical one denotes the normalized action S(Ψa )/S(ΨS ), where ΨS is the Schnabl
solution. The label (L, 3L) for each “curve” denotes thetruncation level.

(5)Here, (4) imposes the a-gauge condition, i.e.,
OGF = b0 M + ab0 c0 Q̃

(|a| < ∞)

(6)

or
†
∗1

results for the gauge invariant overlap4) Oη (Ψ), where

Condensed from the article in Prog. Theor. Phys. 121, 695(2009)
Department of Physics, Nara Women’s UniversityOη (Ψ) = ⟨γ̂(1c , 2)|Φη ⟩1c |Ψ⟩2 ,

-v-

(12)

Fig. 2. Plots of the gauge invariant overlap for various
a-gauge solutions Ψa in the (L, 3L) truncation. The
horizontal axis denotes the value of a and the vertical one denotes the normalized gauge invariant overlapOη (Ψa )/Oη (ΨS ).

in the (L, 3L) truncation are plotted in Fig. 2. We
display plots of the action and overlap for various a
including a = ∞ in Fig. 3. Table 1 shows the values ofgauge invariants for the numerical solution in the (a =0)-gauge, which is equivalent to the Siegel gauge.a)

Fig. 3. Plots of gauge invariants for various a-gauge solutions Ψa in the (L, 3L) truncation. The horizontal axis denotes the ratio of the action S(Ψa )/S(ΨS )and the vertical one denotes that of the gauge invariant overlap Oη (Ψa )/Oη (ΨS ). Each point denotes(S(Ψa )/S(ΨS ), Oη (Ψa )/Oη (ΨS )) for diﬀerent values ofa. The left part of the “curve” for each level corresponds to 4 . a < +∞ and the right part corresponds
to −∞ < a . 1/2. The plots for a → +∞ and a → −∞are continuously connected at that of the Landau gauge((a = ∞)-gauge).
a)

The action for the numerical solution in the Siegel gauge was
evaluated in the earlier literature5) up to level (18, 54). The
gauge invariant overlap for the solution was evaluated in ourprevious paper4) up to level (10, 30) using our Mathematica
program. Here, we made the new record of the truncationlevel up to (24, 72)6) . Calculations for higher truncationlevels (L ≥ 18) in Table 1 were performed by our C++
and Fortran program using our PC cluster in Nara Women’s- vi -(L, 3L)(0,0)(2,6)(4,12)(6,18)(8,24)(10,30)(12,36)(14,42)(16,48)(18,54)(20,60)(22,66)(24,72)S(Ψa=0 )/S(ΨS )0.6846162
0.9593766
0.9878218
0.9951771
0.9979301
0.9991825
0.9998223
1.0001737
1.0003755
1.0004937
1.0005630
1.0006023
1.0006227

Oη (Ψa=0 )/Oη (ΨS )0.7165627
0.8898618
0.9319524
0.9510789
0.9611748
0.9681148
0.9725595
0.9761715
0.9786768
0.9809045
0.9825168
0.9840334
0.9851603

Table 1. The value of the action and the gauge invariant
overlap for the numerical solution with (L, 3L) truncation in the Siegel gauge ((a = 0)-gauge). The values arenormalized by the analytic result for Schnabl’s solution.
P
an
If we use the ﬁtting function5) FN (L) = N
n=0 (L+1)nusing data for L = 0, 2, · · · , 24 (N = 13), we obtain theextrapolated value of the action: 1.0000075 for L = ∞.

Except for the region at approximately a = 1, where
the a-gauge condition is ill deﬁned perturbatively andthe iterations given by (4) and (5) do not converge inthe limit n → ∞, the values of both gauge invariants
approach those of the Schnabl solution as truncationlevel increases. The same tendency is observed in thelevel (L, 2L) calculation.
The calculated values of the gauge invariants are numerically stable and almost equal to those of Schnabl
solution in the region where the gauge parameter a iswell deﬁned. These results provide further evidence ofthe gauge equivalence of various numerical and analytical solutions. It may further imply that the nonperturbative vacuum in bosonic open string ﬁeld theory,
where the original D-brane vanishes, is unique.
References
1) M. Schnabl: Adv. Theor. Math. Phys. 10, 433 (2006).
2) M. Asano and M. Kato: Prog. Theor. Phys. 117, 569(2007), Nucl. Phys. B 807, 348 (2009).
3) M. Asano and M. Kato: JHEP 0701, 028 (2007).
4) T. Kawano, I. Kishimoto and T. Takahashi: Nucl. Phys.
B 803, 135 (2008).
5) D. Gaiotto and L. Rastelli: JHEP 0308, 048 (2003).
6) I. Kishimoto: Talk at APCTP Focus Program on Current Trends in String Field Theory, Pohang, Korea, December 11, 2009.

University, the Computer Facility of the Yukawa Institutefor Theoretical Physics in Kyoto University and the RIKEN
Integrated Cluster of Clusters (RICC). In our computation
for the level (22, 66) and (24, 72), we have used the su(1, 1)singlet basis, which is a consistent truncation in the Siegel
gauge.

RIKEN Accel. Prog. Rep. 43 (2010)

Localization of γH2AX Fluorescence along Tracks of Argon Beams
K. Takagi*1, T. Tsukada, M. Izumi, Y. Kazama, Y. Hayashi, and T. Abe[γH2AX, DSB, heavy ion]

Mutations are generated through lesions in DNA andtheir inappropriate repair. Therefore, it is important toinvestigate the process of DNA damage for studying effectsof heavy-ion beams on mutagenesis.
H2AX is one of the subtypes of the histone 2 family.
When a DNA double strand break (DSB) occurs in a cell
nucleus, H2AXs near the DSB site are phosphorylated at aserine residue near its carboxy terminal to form a cluster ofphosphorylated H2AX ( γ H2AX), the so-called γ
H2AX ”focus”1). Therefore, one can predict locations of
DSB sites in cell nuclei by detecting γH2AX foci.

Fig. 1. Cell culture chamber for the irradiation
For studying the effects of argon beams on DSB formation
along their flight paths, a confluent cell layer of BALB-3T3
mouse fibroblast cell line was placed parallel to the beamaxis, as indicated in Fig.1, and 40Ar17+beams (95MeV/nucleon) radiated on the cell layer at an initial fluenceof 1 particle per 100 µm2. The cell layer was fixed 30 min
after the irradiation, and γH2AX was detected by meansof immunofluorescent microscopy using an antibody raised
against γH2AX.

*1 The Wakasa Wan Energy Research Center

Fig. 2. LET change and corresponding γH2AX focilocalization
Red color in the photograph indicates cellular nuclei,
and yellow color indicates immunofluoresecnce ofγH2AX.

- vii -

Figure 2 shows depth dependent changes in the LET, andγH2AX fluorescence in the corresponding region. The
fluorescence intensity was increased with the increase of
LET, and it almost disappeared corresponding to theabrupt decrease of LET . The photographs in Figs. 3A-D
indicate the localization of γH2AX at depth of 2, 4, 6, and12.5 mm, respectively. At the depth of 2 mm (Fig. 3A),
γH2AX fluorescence revealed straight lines, implying thatthe DSBs were so dense along a particle track that eachfocus was indistinguishable. Figure 3C shows cells at thedepth of 6 mm. This position is near the peak of LET. The
γH2AX fluorescence intensity increased, and extended tothe entire cellular nuclear area in some cells. Interestingly,
there seem to be more lines of γH2AX fluorescence in
Fig.3C than in Fig. 3A and B, and some lines appear as
dotted lines, suggesting the existence of particles, having
lower LET than the original argon ions had. Theseobservations might be the result of nuclear fragmentation.
Figure 3D depicts cells at the depth of 12.5 mm, where wasapparently out of the range of the argon ions. A γH2AX
fluorescence line can be seen at the center of a photograph.
The fluorescence suggests the presence of afragmentation-derived particle that had lower LET than theoriginal argon ion at shallower region had.
In the present study, we observed a straight line of γ
H2AX fluorescence parallel to the beam axis. The
fluorescence intensity gradually increased as the LET ofparticles increased, and it almost disappeared in regions
beyond the range of the argon ions. These results imply
that argon ions cause dense DSB along their flight path.
Further, the present study shows some behaviors ofheavy ions in living tissues. Tracks of the projectile werevisualized as lines of γH2AX fluorescence, and somesigns of nuclear fragmentation were inferred from dottedlines of fluorescence. Those results are probably the firstvisual evidence of nuclear fragmentation in cellular nuclei.
Reference
1) E. Rogakou et al.: J. Biol. Chem. 273, 5858 (1998).

Fig. 3. Localization of γH2AX foci at the different depth
Panel A-D indicates the photograph at the depth of 2(A), 4 (B), 6 (C), and 12.5 mm (D), respectively. Eachscale bar in panels indicates a length of 50 µm.

- viii -RIKEN Accel. Prog. Rep. 43 (2010)

α-fine structure spectroscopy for 257 Lr and 259 Lr
M. Asai,∗1 H. Haba, Y. Kasamatsu, N. Sato,∗1 K. Tsukada,∗1 and T.K. Sato,∗1
��
Nuclear structure, 257 Lr, 259 Lr, α decay∗1

Advanced Science Research Center, Japan Atomic Energy
Agency- ix -

with two Si detectors. To achieve a good α-energy resolution and to reduce a low-energy tail of α peaks, Si
detectors were set at the distance with a solid angle of
13% of 4π. This setup also reduces energy sum between
α particles and subsequently emitted conversion electrons, Auger electrons, and low-energy X rays which
considerably distorts the measured α-energy spectrum.
This energy sum becomes signiﬁcant when α sources
are implanted into a Si detector by a recoil separator
like Ref. 2, which makes it impossible to observe α ﬁne
structure and to determine α energies and intensities
precisely. The present setup using a gas-jet transportsystem and a rotating wheel system is of great advantage to observing α ﬁne structure precisely.
Figure 1 shows a measured α energy spectrum for257
Lr. The α energy resolution of ∼12 keV FWHM
was achieved. We can clearly see a weak α line atenergy by 62 keV lower than that of the most intense
α line of 257 Lr. These α lines are considered to be thetransitions to the rotational band members of the onequasiparticle state whose conﬁguration is the same asthat of the ground state of 257 Lr. Taking into accountenergy diﬀerence and intensity ratio of α transitions
to rotational band members, we can assign a singleparticle conﬁguration of the ground state of the parent
nucleus as well as the populated levels in the daughter.
The energy diﬀerence of 62 keV agrees well with thatbetween the 7/2− bandhead and the 9/2− member ofthe 7/2−[514] band in neighboring nuclei. A similar
result was obtained for the α decay of 259 Lr.
References

1) F.P. Heßberger et al.: Eur. Phys. J. A 26, 233 (2005).
2) A. Chatillon et al.: Eur. Phys. J. A 30, 397 (2006).

100

Counts / 4 keV

Energy spacings and order of single-particle orbitals
are sensitive probes to investigating shell structure ofsuperheavy nuclei. In particular, energies of the proton orbitals around Z = 101, 103, and 105 (Md, Lr,and Db) are interesting because one orbital, 1/2−[521],
which originally lies just above the Z = 114 gap in
a spherical nucleus comes down to the Fermi level in
deformed nuclei around Z = 101–105. Experimental
assignments of the deformed proton orbitals aroundZ = 101–105 thus give us valuable information on thespherical shell gap energy around Z = 114.
Experimental data on the single-particle states in
odd-mass Md, Lr, and Db isotopes are, however, very
scarce because spectroscopy of such heavy nuclei are
extremely diﬃcult. There is no ﬁrm information on
excitation energies, spin-parities, and proton conﬁgurations of ground- as well as excited states in odd-mass
Md, Lr, and Db isotopes except for the ground-state
conﬁgurations of some Md isotopes.1)
Recently, Chatillon et al.2) studied the α decay of255
Lr using a recoil separator and a cold fusion reaction of 209 Bi(48 Ca,2n)255 Lr. They found an α-decaying
isomer in 255 Lr and proposed proton conﬁgurations of
1/2− [521] and 7/2−[514] for 255g Lr and 255m Lr, respectively. To deﬁnitely identify the spin-parities andconﬁgurations, spectroscopic data for α- or γ transitions are indispensable. However, in the α decay of
255g,mLr, no γ ray was observed in coincidence with α
particles,2) because those α transitions would directly
populate the 7/2− [514] ground state or the 1/2−[521]isomer in 251 Md. The same situation is expected in the
α decay of other odd-mass Lr isotopes, which makes
it impossible to assign spin-parities of the Lr isotopes
through γ-ray spectroscopy. To study such nuclei, we
proposed high-resolution α-ﬁne structure spectroscopy
which allows us to identify single-particle conﬁgurations only by measuring an α-singles spectrum. In thepresent work, we applied this technique to studying
the α decay of 257 Lr and 259 Lr.
The nuclei 257 Lr and 259 Lr were produced in the248
Cm(14 N,5n)257 Lr and 248 Cm(15 N,4n)259 Lr reactions using the RIKEN AVF cyclotron. Reaction products were transported through a 10-m long capillarywith a He/KCl jet into a rotating-wheel α-detection
system, and deposited on a thin foil forty of whichwere set on the rotating wheel. The wheel periodicallyrotated to move the deposited sources to seven consecutive detector stations each of which was equipped

50

0

248

14

Cm( N,xn)

257

256

Lr

258

Lr

Lr

8000
8500
D Energy (keV)

9000

Fig. 1. Measured α energy spectrum for 257 Lr.

RIKEN Accel. Prog. Rep. 43 (2010)

In-beam γ-ray spectroscopy of 32 Ne†
P. Doornenbal, H. Scheit,1 N. Aoi, S. Takeuchi, K. Li,1 E. Takeshita, H. Wang,1 H. Baba, S. Deguchi,2N. Fukuda, H. Geissel,3 R. Gernhäuser,4 J. Gibelin,5 I. Hachiuma,6 Y. Hara,7 C. Hinke,4 N. Inabe, K. Itahashi,
S. Itoh,8 D. Kameda, S. Kanno, Y. Kawada,2 N. Kobayashi,2 Y. Kondo, R. Krücken,4 T. Kubo, T. Kuboki,6
K. Kusaka, M. Lantz, S. Michimasa,9 T. Motobayashi, T. Nakamura,2 T. Nakao,8 K. Namihira,6 S. Nishimura,T. Ohnishi, M. Ohtake, N. Orr,5 H. Otsu, K. Ozeki Y. Satou,2 S. Shimoura,9 T. Sumikama,10 H. Takeda,
K. N. Tanaka,2 K. Tanaka, Y. Togano, M. Winkler,3 Y. Yanagisawa, K. Yoneda, A. Yoshida, K. Yoshida and
H. Sakurai,[Nuclear structure, Island of Inversion, neutron-rich nuclei, in-beam γ-ray spectroscopy]
The region around neutron-rich N = 20 nuclei has
drawn strong theoretical and experimental attractionin the last few decades, as it was discovered that thewell-known magic numbers are not global over the
Segré chart and assuming only magic regions, i.e., regions in which a certain set of magic numbers is valid,
seems more appropriate. Despite grand eﬀorts, the exact dimension of the region of the “Island of Inversion”,
a region in which the N = 20 shell closure disappears,
are not established experimentally. In particular, data
for neutron rich Ne isotopes are very scarce.
Here, we report on the ﬁrst in-beam γ-ray spectroscopic study performed at the Radioactive Ion Beam
Facility, aiming for the determination of the ﬁrst excited state of 32 Ne. Its value provides a measure if
the the N = 20 shell is closed in this nucleus or not.
A 48 Ca primary beam of 120 pnA average intensity
impinged at an energy of 345 MeV/u on a 20 mm rotating Be target mounted at the focus F0 of the fragment separator BigRIPS1) . The secondary beams wereseparated and selected in the ﬁrst stage of BigRIPS,
employing the Bρ–∆E–Bρ method with a 15 mm thick
Al wedge degrader at the dispersive focus F1.
The particles were identiﬁed in the second stage ofBigRIPS based on the ∆E–TOF–Bρ method. The energy loss (∆E) was measured with an ion-chamber2)
located at the focus F7, the time-of-ﬂight (TOF) was
deduced from two plastic scintillators located at thefoci F3 and F7, while the Bρ was obtained from position measurements with parallel plate avalanche counters3) at the foci F3 and F5.
The main constituents of the secondary beam were33
Na (26 pps) and 32 Ne (6 pps), which were transported to the focus F8 and incident on a 2.54 g/cm2

thick (natural) carbon target at mid-target energies of
245 and 226 MeV/u, respectively. After the secondary
target, the particle spectrometer ZeroDegree was employed to select and identify the reaction residues by
the same methods as described for BigRIPS.
To detect γ-rays emitted from excited states in 32 Ne,
the secondary target was surrounded by 180 large volume NaI(Tl) crystals, the DALI2 array4). After lessthan eight hours measuring time, γ-ray transitions
were seen in the inelastically scattered 32 Ne and theone-proton removal reaction from 33 Na, which we as+signed to the 2+
1 → 0gs decay. The spectra are shownin Fig. 1, revealing a single γ-ray peak at 722(9) keV
for the sum spectrum of both reaction channels.
A comparison with shell-model calculations by Utsuno et al.5) and Caurier et al.6) showed that this low
excitation energy accords with the original perception
about the dimension of the “Island of Inversion”, i.e.,
it extends at least to the neutron number N = 22 for
the Ne isotopes.
33

32

*

C( Na, Ne )

a)

32

32

*

C( Ne, Ne )b)

Counts / 25 keV

20
15
10
5
0

0

500 1000 1500 2000 0
Eγ (keV)

500 1000 1500 2000
Eγ (keV)Fig. 1. Doppler corrected γ-ray spectra from DALI2 following one-proton removal of 33 Na (a) and inelasticallyscattered 32 Ne (b).

†Condensed from the article in Phys. Rev. Lett. 103, 032501(2009)∗1 Peking University, China∗2 Department of physics, Tokyo Institute of Technology∗3 GSI, Darmstadt, Germany∗4 Tech. Univ. München, Germany∗5 LPC Caen, France∗6 Department of Physics, Saitama University∗7 Department of Physics, Rikkyo University∗8 Department of Physics, University of Tokyo∗9 Center for Nuclear Study, The Univ. of Tokyo∗10 Tokyo University of Science

References
1) T. Kubo et al., Nucl. Instr. Meth. B 204, 97 (2003).
2) H. Otsu et al., RIKEN Accel. Prog. Rep. 42, 163 (2009).
3) T. Ohnishi et al., J. Phys. Soc. Jpn. 77, 083201 (2008).
4) S. Takeuchi et al., RIKEN Accel. Prog. Rep. 36, 148(2003).
5) Y. Utsuno et al., Phys. Rev. C 60, 054315 (1999).
6) E. Caurier et al., Nucl. Phys. A693, 374 (2001).

-x-

RIKEN Accel. Prog. Rep. 43 (2010)

Complete Set of Deuteron Analyzing Powers for dp Elastic
Scattering at 250 MeV/nucleon and Three-Nucleon Forces
K. Sekiguchi, H. Okamura,∗1 N. Sakamoto, H. Suzuki,∗2 M. Dozono,∗3 Y. Maeda,∗4 T. Saito,∗4 S. Sakaguchi,
H. Sakai,∗5 M. Sasano, Y. Shimizu, T. Wakasa,∗3 and K. Yako,∗5
The study of three-nucleon forces (3NFs) is important for clarifying nuclear phenomena. The ﬁrst signature of the 3NF was found in the binding energies of the 3 H and 3 He, and the signiﬁcance of 3NFs
has recently been pointed out in providing descriptions of discrete states in higher mass nuclei. The
study of three-nucleon scattering at intermediate energies (E/A ∼ 200 MeV) is a promising approach forinvestigating the dynamical aspects of 3NFs, such as
momentum and/or spin dependence. The experimental studies by polarized deuterons beams at intermediate energies are being carried out at the RIKEN RI
Beam Factory with the aim of clarifying roles of the
3NFs in nuclei. As the ﬁrst step, we have measured acomplete set of deuteron analyzing powers (iT11 , T20 ,T21 , and T22 ) for deuteron–proton (dp) elastic scattering at 250 MeV/nucleon.
A schematic diagram of the experimental setup has
been provided in Ref. (1). First vector- and tensor- polarized deuteron beams were accelerated by the injector cyclotrons AVF and RRC up to 90 MeV/nucleon;
subsequently; they were accelerated up to 250 MeV/
nucleon by the new superconducting cyclotron SRC.
The polarization axis of each beam was rotated by using a Wien ﬁlter system prior to their acceleration2) .
Therefore, single-turn extraction of the beams from all
three cyclotrons, AVF, RRC, and SRC was required inorder to maintain the polarization amplitudes during
acceleration. The typical values of the beam polarizations determined by the experiment were 80% of
the theoretical maximum values. Note that the beampolarizations were monitored continuously by using abeam line polarimeter, Dpol, prior to acceleration by
the SRC. The dp elastic scattering was performed byusing a detector system, BigDpol, which was installedat the extraction beam line of the SRC. Polyethylene(CH2 ) with a thickness of 330 mg/cm2 was used as
the hydrogen target. In BigDpol, four pairs of plastic
scintillators coupled with photo-multiplier tubes wereplaced symmetrically in the directions of azimuthal
angles to the left, right, up and down. Scattereddeuterons and recoil protons were detected in kinematical coincidence condition by each pair of detectors.
The angles (θc.m. ) measured in the center-of-mass system are in the range 40◦ –162◦ . In the experiment,
∗1
∗2
∗3
∗4
∗5

RCNP, Osaka University
University of Tsukuba
Kyushu University
Miyazaki University
University of Tokyo- xi -

the deuteron beams were stopped in the Faraday cup
which was installed at the focal plane F0 of the BigRIPS spectrometer.
Angular distributions of all deuteron analyzing powers iT11 , T20 , T21 , and T22 represented by open circles in Fig. 1. The statistical errors are also shown.
The dark (light) shaded bands in the ﬁgure represent the Faddeev calculations with (w/o) the TucsonMelbourne99 3NF3) based on modern NN potentials,
namely CDBonn5) , AV186) , and Nijmegen I and II7) .
The solid lines represent the results of the calculations
with the Urbana IX 3NF4) based on the AV18 potential. Good agreements between the data and the calculations with the 3NFs are obtained at forward angles
given by θc.m. ≤ 120◦ ; however, at backward angles,
good agreements are not observed even when 3NFs areincluded. These results are quite similar to those obtained for the cross section and proton analyzing powerfor pd/nd elastic scattering at 250 MeV/nucleon8,9) .

Fig. 1. Deuteron analyzing powers iT11 , T20 , T21 , and T22
for dp elastic scattering at 250 MeV/nucleon.

References
1) K. Sekiguchi et al.: RIKEN Accel. Prog. Rep. 42, 27(2009).
2) H. Okamura et al.: AIP Conf. Proc. 343, 123 (1995).
3) S. A. Coon and H. K. Han: Few Body Syst. 30, 131(2001).
4) B. S. Pudliner et al.: Phys. Rev. C56, 1720 (1997).
5) R. Machleidt: Phys. Rev. C 63, 024001 (2001).
6) R. B. Wiringa et al.: Phys. Rev. C 51, 38 (1995).
7) V. G. J. Stoks et al.: Phys. Rev. C 49, 2950 (1994).
8) K. Hatanaka et al.: Phys. Rev. C 66, 044002 (2002).
9) Y. Maeda et al.: Phys. Rev. C 76, 014004 (2007).

RIKEN Accel. Prog. Rep. 43 (2010)

Negative-parity excitations unique in deformed neutron-rich nuclei
close to the drip line†
Kenichi Yoshida[Nuclear structure, Density functional theory, Unstable nuclei]

Strength (fm6)Strength (e2fm2)

0.08
0.06

40

Mg
dipole

Kπ=1−

0.04
0.02
0
6000
5000
4000
3000
2000
1000
0

octupole

0 2 4 6 8 10

ω (MeV)

Fig. 1. Transition strengths for the K π = 1− isovector (IV)dipole (upper) and isoscalar (IS) octupole (lower) excitations in 40 Mg. The arrow indicates the neutronemission threshold energy.
†

1400
1200
1000
800
600
400
200
0

36

SIS1 (fm6/MeV)

Study of the multipole responses in unstable nuclei is of considerable interest because the multipole
responses can provide information on novel featuresof collective modes of excitation in extreme environments. The surface structure of neutron-rich nuclei
is quite diﬀerent from that of stable nuclei, because of
the presence of the loosely bound neutrons. One of theunique features of neutron-rich nuclei is the presence ofa neutron skin. Since collective excitations are sensitive to the surface structure, we can expect new kindsof exotic excitation modes associated with the neutron
skin to appear in neutron-rich nuclei. An example ofsuch an exotic excitation mode is the soft dipole modeor the pygmy dipole resonance (PDR).
The structure and collectivity of the PDR has beenstudied on the basis of mean-ﬁeld calculations performed by many groups1) . These studies, however,
have been largely restricted to spherical systems. Recently the low-lying dipole excitation in neutron-rich
Ne2) and Sn isotopes3) have been investigated by using deformed quasiparticle-random-phase approximation (QRPA),
In the present study, low-lying negative-parity
excitation modes are investigated using the deformed QRPA on the basis of Skyrme-Hartree-FockBogoliubov (HFB) mean ﬁeld4) . The HFB calculations reveal that Mg isotopes under investigation are

Condensed from article in Phys. Rev. C 80, 044324 (2009).

- xii -

Mg

0 10 20 30 40 0

38

Mg

10 20 30 40 0
E (MeV)

Kπ=0−
Kπ=1−

40

Mg

10 20 30 40

Fig. 2. IS dipole strength distribution in 36,38,40 Mg. The
transition strengths are smeared by a Lorentzian function with a width of Γ = 2 MeV.

prolately deformed and that they have neutron skins;
the neutron-skin thickness of 36 Mg, 38 Mg and 40 Mg
are 0.41 fm, 0.47 fm, and 0.54 fm, respectively.
The low-lying part of the isovector (IV) dipole
strengths are shown in the upper panel of Fig. 1. We
can see a prominent peak at around 8 MeV. The transition density to this state shows the following characteristic feature of PDR: Inside the nucleus and at the surface of the nucleus, protons and neutrons oscillate coherently, while outside the nucleus, only the neutrons
oscillate, and the oscillations of the internal core andthe neutron outside are out of phase. This corresponds
to the classical picture of oscillation of the neutron
skin against the isoscalar core along the ρ−axis, whichis the axis perpendicular to the symmetry axis. It isalso found that in PDR there is signiﬁcant coupling
between the dipole and octupole excitation modes because of the nuclear deformation, as shown in the lower
panel of Fig. 1.
Figure 2 shows the transition strengths for the IS
compressional dipole operator. When the drip line isapproached, we can see a signiﬁcant enhancement of
the transition strengths occurring above the neutronemission threshold energy; the transition strengths increase up to ∼ 15 MeV. Since such an enhancementof the transition strengths in the lower-energy region
is not observed in stable nuclei, we can conclude that
it is one of the unique features of drip-line nuclei, andit occurs due to the strong mixing between the IS andIV modes and due to the presence of the neutron skin.
References
1) N. Paar et al.: Rep. Prog. Phys. 70, 691 (2007).
2) K. Yoshida et al.: Phys. Rev. C 78, 014305 (2008).
3) D. P. Arteaga et al.: Phys. Rev. C 79, 034311 (2009).
4) K. Yoshida et al.: Phys. Rev. C 78, 064316 (2008).

RIKEN Accel. Prog. Rep. 43 (2010)

Lattice QCD study of ΛN interaction †H. Nemura, for HAL QCD Collaboration,[ Lattice QCD, Hyperon-Nucleon interaction, Nuclear forces, Hypernuclei]†

Condensed from the previously published article1) .

30

50

VC(mπ ≅ 407 MeV)
VC(mπ ≅ 512 MeV)
VT(mπ ≅ 407 MeV)
VT(mπ ≅ 512 MeV)

30

20

20

V (MeV)r2 V (MeV·fm2)

40

10

10
0
-10
-20

0

-30
-40

-10

-50
0.0

0.5

0.0

0.5

r (fm)

1.0

1.5

2.0

r (fm)

Fig. 1. The central and the tensor potentials in 3 S1 −3 D1channel of ΛN system in quenched QCD at mπ  407
MeV (downward-triangle and diamond) and 512 MeV(upward-triangle and circle).
30

50mπ ≅ 407 MeV
mπ ≅ 512 MeV

40
30

20

20

V (MeV)r2 V (MeV·fm2)

Baryon-baryon interaction is one of the important topics in nuclear physics. For the sector withstrangeness S = 0, modern nucleon-nucleon (N N ) potentials provide a good description of the N N scattering data at low energies. These N N potentials together with three-nucleon (N N N ) forces have been
considered for precision calculations in normal lightnuclei2) . In contrast, hyperon-nucleon (Y N ) andhyperon-hyperon (Y Y ) interactions involve large uncertainties because the scattering experiments are either difficult or impossible due to the short lifetimesof hyperons. The present phenomenological Y N and
Y Y interaction models are not well constrained by experimental data. The characteristics of the Y N and
Y Y interactions are important for studying the composition of hyperonic matter in neutron stars. For example, according to recent experimental and theoretical studies on Σ hypernuclei, Σ-nucleus interaction appears to be repulsive. Therefore, a Λ particle, insteadof Σ− , would be the first strange baryon to appear in
the cores of neutron stars. Moreover, the quantitative
information of the Y Y (e.g., ΛΛ) interaction could help
to clarify the cooling mechanism of neutron stars.
Lattice QCD is a valuable theoretical tool for the
first-principle calculation of baryon-baryon interactions. Recently, a new approach has been proposed to
study the N N interaction using lattice QCD3,4) . We
study the ΛN potential by adopting this approach. In
this article, the results of quenched QCD calculation
performed by utilizing the plaquette gauge action andthe Wilson quark action at β = 5.7 on a 323 ×48 lattice
are presented. The lattice spacing at the physical point
is determined as a ≈ 0.14 fm from the ρ-meson mass.
The spatial lattice volume is approximately (4.5 fm)3 .
Figures 1 and 2 show the ΛN potentials obtained by
the quenched QCD calculation. For the channel withangular momentum and parity J π = 1+ , the central(VC ) and the tensor (VT ) potentials are shown in theFig. 1, while VC for the channel with J π = 0+ is shownin Fig. 2. To compare the strengths of the repulsive
cores for two quark masses, the central potential multiplied by volume factor, i.e., r2 VC (r), is shown in theleft panel of each figure; the normal V (r) is shown in
the right panel of each figure. These figures present
results for (mπ , mK ) ≈ (512, 606) and (407, 565) MeV.
As evident in both figures, the attractive well of thecentral potential slightly moves to outer direction as
the u and d quark masses decrease, whereas the depthof these attractive pockets do not change considerably.

10

10
0
-10
-20

0

-30
-40

-10

-50
0.0

0.5

r (fm)

0.5

1.0

1.5

2.0

r (fm)

Fig. 2. The central potential in 1 S0 channel of ΛN system in quenched QCD at mπ  407 MeV (downward
triangle) and 512 MeV (circle).

The present results show that the tensor force is weaker
than the N N interaction, and the dependence of thetensor force on quark mass appears to be small. Bothof the repulsive and attractive parts increase in magnitude as the u and d quark masses decrease. Calculations involving 2 + 1 flavor full QCD gauge configurations that are generated by PACS-CS collaboration5)
are also in progress.
References
1) H. Nemura, for HAL QCD Collaboration: Proceedingsof the 10th International Conference on Hypernuclear
and Strange Particle Physics (Hyp-X), Nucl. Phys. A
835, 176 (2010).
2) S. C. Pieper, Riv. Nuovo Cim. 031, 709 (2008)[arXiv:0711.1500 [nucl-th]].
3) N. Ishii, S. Aoki, T. Hatsuda: Phys. Rev. Lett. 99,022001 (2007).
4) S. Aoki, T. Hatsuda and N. Ishii: Prog. Theor. Phys.
123, 89 (2010), arXiv:0909.5585 [hep-lat].
5) S. Aoki et al. [PACS-CS Collaboration]: Phys. Rev. D79,
034503 (2009), arXiv:0807.1661 [hep-lat].

- xiii -RIKEN Accel. Prog. Rep. 43 (2010)

W -Boson Production by Polarized p+p Collisions√
at s = 500 GeV
K. Karatsu∗1 from the PHENIX Collaboration[nucleon spin, W-boson, polarized parton distribution]∗1

Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan

pp → π +X
pp → π -X+
pp → W X → e+ν X
pp → W X → e- ν X

10∆φ = π , -0.35 < η < 0.35
s = 500 GeV

d σ /dpT (pb/GeV)

102

1

10-120

25

30

35

40

45

50

pT (GeV)3

10

Raw Yield (positive charge)(w.o. isolation cut)data"power-law + w" curve (unnormalized)
power-law curve (unnormalized)102

w curve (unnormalized)

3

10

Raw Yield (positive charge)(w. isolation cut)data"power-law + w" curve (unnormalized)
power-law curve (unnormalized)102

w curve (unnormalized)

10

10

1

1
10

yield

Fig. 1. Expected yields in the PHENIX central arms;e− (purple) and e+ (blue) are produced by W decay(data obtained using RHICBOS5) ). π + (black) andπ − (red) are produced by other processes (data obtainedby pQCD calculation). No particle identiﬁcation was
performed.
yield

Although the polarizations of valence quarks havebeen determined well by DIS (Deep Inelastic Scattering) and Semi-Inclusive DIS1) , large uncertainty about
the polarization of sea quarks still exists. One of themain objectives at RHIC involving polarized p+p collisions is to measure the polarization of sea quarks byproducing W bosons2) . The single-spin asymmetry(AL ) in W -boson production is a clear indication of
the polarization of sea quarks since the chirality of theinteracting quarks is conserved in the V-A coupling. It
is also possible to identify the ﬂavor of the sea quarks
by the charge-separated measurement of W + /W −3) .
PHENIX4) is a detector system that is capable ofmeasuring leptons produced by W decay at midrapidity (|η| < 0.35, PHENIX central arms) and forward
rapidity (1.2 < |η| < 2.4, PHENIX muon arms).
The run held in 2009√ at RHIC (RHIC Run9) is theﬁrst collisions with s = 500 GeV. This was also
the ﬁrst opportunity for PHENIX to measure significant amounts of W bosons. The ﬁrst attempt tomeasure electrons produced by W decay was madeusing the PHENIX central arms, which are capableof good tracking and rejection of hadron background,along with drift chambers (DC) and electromagnetic
calorimeters (EMCal).
In W decay, although the yields of pions (π + and−π ) exceed the yield of the electrons at the same pT ,as shown in Fig. 12) , on the basis of the ratio of thedeposited energy in the EMCal to the observed particle momentum (E/p cut), the pions are expected to be
rejected by a factor of 100 since only a fraction of thetotal deposited energy is contributed by the pions. Additionally, an electron isolation cut, which requires nojet activity in the vicinity of the electron, is expected
to reduce the pion background by a factor of 3 to 10.
As a result of the these two types of pion rejections,the electrons produced by W decay in the PHENIX
central arms can be measured.
Fig. 2 shows the pT spectra of raw yields obtained
from RHIC Run9 data. The left plot shows the spectrum obtained without applying the isolation cut andthe right shows the spectrum obtained by applying theisolation cut. These plots show that as expected, theisolation cut enhances the signal to background ratioof the W -decay electrons by reducing the hadron background by a factor of 3 to 5 (the E/p cut has been
applied in both plots).

15

20

25

30

35

40

45
50
pT[GeV]

10

15

20

25

30

35

40

45
50
pT[GeV]

Fig. 2. Spectrum of raw yields of positively charged particles in high-pT events (pT > 10 GeV) (Left: without
isolation cut, Right: isolation cut applied). The E/p
cut has been applied in both plots. A power-law function (blue) and W curve from RHICBOS5) (purple) areoverlaid (unnormalized; curve obtained from RHICBOS
is smeared).

Further analysis to calculate the cross section andthe single-spin asymmetry of W -boson production iscurrently underway, and the results will provide theﬁrst direct measurement of sea-quark polarization.
References
1) D. de Florian, R. Sassot, M. Stratmann, and W. Vogelsang: Phys. Rev. Lett. 101:072001, (2008).
2) 2008 RHIC Spin Plan Report
3) G. Bunce, N. Saito, J. Soﬀer, and W. Vogelsang: Ann.
Rev. Nucl. Part. Sci. 50, 525 (2000).
4) PHENIX collaboration: Nucl. Instrum. Meth. A 499,
469 (2003).
5) P. M. Nadolsky and C. P. Yuan: Nucl. Phys. B 666, 31(2003); hep-ph/0304002.

- xiv -

RIKEN Accel. Prog. Rep. 43 (2010)

Application of a Pair of Solenoid Magnets in Beam Transport Line
Yoichi Sato,∗1 Jun-ichi Ohnishi, Nobuhisa Fukunishi, Akira Goto, and Hiroki Okuno
KB = BB,sol /(2Bρ0 ), and Bρ0 is the momentum rigidity of a beam. Ltot = LA,eﬀ + L + LB,eﬀ , where L isthe drift space of Rdrift . γ is the Lorentz factor. If
KA KB < 0 and constant θAB , we can use the solenoids
on a beam line as a focusing lens set with a ﬁxed rotational angle around the beam axis. For example,
a series of two identical solenoids, i.e., pair solenoids,with equal current in opposite directions has no rotational components, and the horizontal and verticaldirections are decoupled since BA,sol = −BB,sol = Bsoland LA,eﬀ = LB,eﬀ = Leﬀ owing to which θAB = 0.
The new injector of the RIBF project, RILAC2, isunder construction and is designed to produce highintensity uranium ion beam by late 20106–8) . The
LEBT of RILAC2 is the beam transport line fromthe 28 GHz superconducting electron cyclotron resonance ion source (ECRIS) to the entrance of the radiofrequency quadrupole (RFQ), and this beam transport line has been designed to include two sets of pairsolenoids. In Fig. 1, SOL12 and SOL34 are the pairsolenoids. Figure 2 shows their layouts. The pairsolenoids are used to reduce the beam diameter as thebeam passes from SOL12 to the RFQ. In each solenoid
pair, the two solenoids have equal current with opposite directions: this helps in the decoupling of beamemittances. The decoupling feature enables us to control the downstream elements on the basis of the projected diagnostics, as measured upstream of the pairsolenoids. The four quadrupoles between SOL12 andSOL34 are used only for matching the beam with RFQ
acceptance. In LEBT, the only horizontal and vertical
coupling lens elements are the solenoids of the ECRIS
and the solenoid SOL0 following the ion source.
In addition to decoupling feature for emittance,pair solenoids can be used to achieve a smaller beamRB,sol (BB,sol , LB,eﬀ ) ⊗ Rdrift ⊗ RA,sol (BA,sol , LA,eﬀ ) radii in the magnets than that achieved by using thequadrupoles. Figure 3 shows the beam envelopes for a= (RB,rot ⊗ RA,rot ) ⊗ (RB,focus ⊗ Rdrift ⊗ RA,focus )pair solenoids and quadrupole magnets under identical= Rrot (θAB )initial conditions in the RILAC2 LEBT design. The
R11 R1200
00quadrupoles are needed to match the beam emittances R21 R22
0
0
0
0


with the acceptance of the RFQ and the buncher.
 00
R33 R34 00(1) The beam radii are reduced to half by introducing an⊗,
0R43 R44 00 0other pair of solenoids. For beam matching, the pair
 0
0
0
0
1 Ltot /γ 2 solenoids can be substituted by a series of quadrupoles,
0
0
0
0
0
1
but these quadrupoles require large bore diameters,
thereby, increasing the cost. Moreover, merely increaswhere Rsol (Bsol , Leﬀ ) = Rrot ⊗ Rfocus = Rfocus ⊗ Rrot
ing the number of quadrupoles cannot help reduce theis the solenoid matrix of magnetic ﬁeld Bsol and efbeam radii eﬀectively. In general, for a quadrupole,fective length Leﬀ . Rrot and Rfocus are the rotational
the beam size in its defocusing direction is larger thancomponent and focusing component, respectively, ofthat for a solenoid pair.
the solenoid. The total rotational angle is θAB =The aberration produced by the pair solenoids in
KA LA,eﬀ + KB LB,eﬀ , where KA = BA,sol /(2Bρ0 ),the RILAC2 LEBT is simulated by 3D tracking calcu-

Solenoid pairs can be used to independently determine the rotation and focusing functions. In beamtransport, a solenoid acts as a focusing and rotating lens element. A series of solenoid magnets, withdrift spaces, can be used to cancel the rotation eﬀect
produced by these magnets, if their integrated magnetic ﬂux is zero in the beam line. The beam emittance through these solenoids is decoupled horizontally and vertically. Such decoupling can be used in
the muon-collider cooling channel1–5) . In addition todecoupling, multiple solenoids can be used to control
transversely isotropic focusing without changing thetotal rotational angle. The use of multiple solenoids
is convenient for a short transport line, and multiplesolenoids can be used not only for the muon-collider
but also for other types of beam lines, such as low energy beam transport (LEBT). In this paper, a very
simple technique of using multiple solenoids, i.e., theuse of a pair of identical solenoids is described; thistechnique is used in the design of LEBT for RIKEN’s
Radioisotope Beam Factory (RIBF) project. For agiven injected beam, a pair of solenoids at a speciﬁc
position has smaller bore diameters than a series ofquadrupoles at the same position.
The 6 × 6 transfer matrix of a solenoid lens is the
product of a rotation matrix and a focusing matrix,
which are interchangeable. The rotation matrix anddrift matrix are also interchangeable. Therefore, thetransfer matrix of a series of two solenoids can be expressed as the product of a rotation matrix and a complex of a focusing matrix, a drift matrix, and a focusing
matrix in series, as shown by the ﬁrst-order transfer
matrix of the series of two solenoids connected withdrift space.

∗1yoichi.sato@j-parc.jp, yoichisato@riken.jp- xv -

Fig. 1. Layout of RILAC2 LEBT. The 28 GHz superconducting ECRIS produces U 35+ ions with an accelerating
voltage of 22.3 kV. SOL0 is a single solenoid right after the exit of the ECRIS. SOL12 is the ﬁrst set ofpair solenoids, and SOL34 is the second set of pairsolenoids. There is a diagnostics chamber in front ofeach set. The abbreviations BM, PS, ST, 4Q, BUN,
and RFQ represent the analyzing bending magnet, a
set of pair solenoids, a steering magnet, a series of four
quadrupoles, a buncher ﬁrst harmonic: 18.25 MHz, andan RFQ second harmonic: 36.5 MHz.

lations. SOL12 may produce a 6% emittance growth,
but this value is acceptable in the design of RILAC2
LEBT. SOL34 may not produce any substantial aberration.
In the LEBT design, it is suitable to use the pairsolenoids downstream a long drift space, e.g., a seriesof diagnostics, for operating downstream lens elementswith small apertures. In the RILAC2, a strongly focused beam is required at the entrance of the RFQ.
The RFQ and following linac line have 45◦ inclined
quadrupoles. By setting SOL34 between the 45◦ inclined diagnostics and the RFQ, the linac can be controlled easily.
We express special thanks to M. Fujimaki, Dr. Y.
Higurashi, E. Ikezawa, Dr. O. Kamigaito, M. Kase,
Dr. T. Nakagawa, H. Watanabe, Dr. Y. Watanabe,and S. Yokouchi.
References
1) J. Gallardo et al.: Proc. the 1999 Particle Accelerator
Conf., New York, USA, 1999, p. 3032.
2) H. Kirk: Presented at the Mini-Workshop on Ionization
Cooling, 1998.
3) R. Fernow: Proc. the 1999 Particle Accelerator Conf.,
New York, USA, 1999, p. 3020.
4) V. Balbekov et al.: MUCOOL Note 125 (2000).
5) D. Neuﬀer: Nucl. Instr. and Meth. A 532, 26 (2004).
6) O. Kamigaito et al.: Proc. PASJ6, Tokai, Japan, 2009,p. 38.
7) T. Nakagawa et al.: Presented at International Conference on Ion Sources, Gatlinburg, USA, 2009.
8) Y. Sato et al.: Proc. PASJ6, Tokai, Japan, 2009, p. 801.

- xvi -

Fig. 2. Layout of pair solenoids. SOL12 has a 120 mm bore
diameter, and SOL34 has a 90 mm bore diameter.

Fig. 3. Beam envelopes from the analyzing slit to the RFQ
entrance in RILAC2 LEBT. The upper half shows vertical beam envelopes, and the lower half shows horizontal beam envelopes. The beam comprises U 35+ ions,the acceleration voltage is 22.3 kV, and the horizontal
and vertical emittance values are 200π mm·mrad. The
solid lines indicate the beam envelopes for the case inwhich pair solenoids are placed right after the slit. The
eﬀective length and bore diameter of the lens elements
are indicated by the solid marks in the upper half. The
dashed lines indicate the beam envelopes for the casein which four quadrupole magnets are placed right after the slit. The eﬀective length and bore diameter ofthe lens elements are indicated by the dashed marks in
the lower half. In both cases, pair solenoids are usedin front of the RFQ entrance. The beam envelopes forboth cases are superposed.

RIKEN Accel. Prog. Rep. 43 (2010)

Measurement of charge-state distribution of uranium and xenon
beams with a gas charge stripper
H. Kuboki, H. Okuno, S. Yokouchi, T. Kishida, H. Hasebe, N. Fukunishi, O. Kamigaito, M. Kase, A. Goto, andY. Yanoferent charge states emerged from the gas stripper. A
beam in one charge state was selected and channeleddownstream of the dipole magnets DAD4 and DMD4,
and the magnetic fields were corrected for the energy
loss in the gas. Beam currents of 238 U or 136 Xe in theselected charge state were measured with Faraday cup
F41 (FC-F41) downstream of DMD4.
The fraction F (qi ) of a charge state qi is defined
Beam from RRC

Gas charge stripper
47'$

47'

47'

)&+9

67'

3)

47'
67'

67'

)& )&+9
73 3)

6&,17

)& 3)
73

'UHEXQFKHU

DAD4
DMD4

Faraday cup D16(FC-D16)
67'$

6&,17
3) )&
73

3)
3)

4''$

'0'$

47)

Faraday cup F41(FC-F41)

4')

)&+9

73

3)
73
6&,17

)&

3)

33

3)

'0)
67)
㏿᩿ࣂࣝࣈ
*9

67)

47)

33
3)
)&+9
)&

fRC
Fig. 1. Schematic view of the charge-state distribution
measurement. Please see the text for details.
F41 /qi
as F (qi ) = IID16/qini , where IF41 , ID16 , and qini denotethe beam currents at FC-F41 and FC-D16, and thecharge state of the beam obtained from the ion source,
respectively.
The charge-state distributions of 238 U and 136 Xe

0.18
0.16
0.14
0.12
fraction

Charge strippers are essential components in aheavy-ion accelerator complex such as the RIKEN RI
Beam Factory (RIBF)1) since heavy ions in a highcharge state can be efficiently accelerated at a small
facility. At the RIBF, two strippers are used for theacceleration of uranium (238 U) ions with energies up
to 345 MeV/nucleon2) . The first and second strippers,
which are carbon foils with thicknesses of 0.3 mg/cm2
and 17 mg/cm2 3) , are located downstream of the RRC
and fRC, respectively. The energies of 238 U ions incident on each stripper are 10.75 and 51 MeV/nucleon.
It should be noted that there are two serious problems associated with the first stripper. One is its short
lifetime that is a consequence of the heat load during
irradiation, and the other is the energy spread resulting from the nonuniformity of the foil thickness4) .
We have developed a gas stripper that is a candidate for a long-lifetime stripper with uniform thickness. However, we could not predict whether the
charge states obtained with a gas stripper would be acceptable for the fRC since charge states of heavy ionslike 238 U or xenon (136 Xe) in gaseous media have notbeen studied well at energies around 10 MeV/nucleon.
Therefore, the charge-state distributions of 238 U and136
Xe ions with an energy of 10.75 MeV/nucleon ina gas stripper were measured as functions of the gaspressure up to its equilibrium charge-state distribution. The use of a differential pumping system witha target cell and five pumping stages4,5) made it possible to enhance the nitrogen (N2 ) gas thickness up
to 0.9 mg/cm2 , which was considered to be sufficient
to obtain equilibrium charge states, taking into account that the carbon foil thickness for equilibriumis ∼0.5 mg/cm2 2) . The thickness of the gas stripper
was calculated from the measured gas pressure in thetarget cell by assuming the longitudinal length of thegaseous medium to be equal to the cell length (10 cm).
The charge-state distribution measurements werecarried out as follows: 238 U and 136 Xe ion beams
with charge states of 35+ and 20+ were obtained
from the 18 GHz ECR ion source and accelerated
up to 10.75 MeV/nucleon with the RILAC and RRC.
The beams were transported to the gas stripper located upstream of the fRC, as shown in Fig. 1. The
beam currents incident on the gas stripper were measured at Faraday cup D16 (FC-D16) and were typically 300∼500 enA (9∼14 particle nA) for 238 U and
500∼600 enA (25∼30 particle nA) for 136 Xe. The spot
diameter was about 6 mm, which was comparable tothe orifice at the gas stripper entrance. Beams in dif-

0.10

238

U

N2 0.3 kPa
N2 0.5 kPa
N2 0.9 kPa
N2 2.0 kPa
N2 4.5 kPa

0.08
0.06
0.04
0.02
0

40 42 44 46 48 50 52 54 56 58 60 62 64 66 68
charge states

Fig. 2. Charge-state distribution of 238 U. The data obtained for gas pressures of 0.3, 0.5, 0.9, 2.0, and 4.5 kPa
are denoted by open circles, open triangles, solid triangles, open squares, and solid squares, respectively.

- xvii -Table 1. Obtained parameters of 238 U (left) and 136 Xe (right) charge-state distributions. The gas species
is N2 .

fraction

238

0.24
0.22
0.20
0.18
0.16
0.14
0.12
0.10
0.08
0.06
0.04
0.02
0

pressure (kPa)
0.3

center
51.52

σ
2.92

0.5
0.9
2.0
4.5

0.139
0.158
0.159
0.161

54.23
55.76
55.99
55.95

2.87
2.53
2.51
2.47

136

27

136

U
peak height0.137

N2 0.3 kPa
N2 0.3 kPa
N2 0.5 kPa
N2 0.9 kPa
N2 2.0 kPa
N2 4.5 kPa

Xe

29

31

33

35 37 39 41
charge states

43

45

47

49

most probable charge stateFig. 3. Charge-state distribution of 136 Xe. The data obtained for gas pressures of 0.3, 0.5, 0.9, 2.0, and 4.5 kPa
are denoted by open circles, solid circles, open triangles,
solid triangles, open squares, and solid squares, respectively.
58
56
54
52
50
48
46
44
42
40
38
36
34
42
40
38
36
34
32
30
28
26
24
22
20

(a) 238U
Ar
CO2
N2
He
Air

Ar
CO2
N2
He
Air
20

50
100
200
thickness (µg/cm2)

Xepeak height
0.189
0.178
0.184
0.199
0.207
0.209

center
35.74
36.10
38.48
40.07
40.59
40.51

σ
2.11
2.24
2.16
2.01
1.93
1.91

as the center value of the Gaussian function. All fitted parameters are tabulated in Table 1. The mostprobable charge states with values of 56.0 and 40.5
correspond to the equilibrium charge states for 238 U
and 136 Xe, respectively. It is noticeable that the equilibrium charge states of 136 Xe obtained with the gas
stripper are acceptable for fRC acceleration. The mostprobable charge states are plotted as a function of thegas thickness in Fig. 4. The data of Ar, CO2 , He, andair are plotted together with those of N2 . We have one
datum for He and air. The data are fitted by the function f (t) = a − b exp(−ct), where t is the gas thickness
and a, b, and c are parameters to be determined. The
thickness necessary for equilibrium is calculated by using f (t) and is found to be 59, 86, and 83 µg/cm2
in the case of Ar, CO2 , and N2 , respectively. As for
136
Xe, the thicknesses necessary for equilibrium are 78,
111, and 104 µg/cm2 . These values are far less thanthat of carbon foil. This fact indicates that there aredifferences in the physical process of charge-stripping
between a gas stripper and a solid stripper. Investigation of these differences is currently in progress.
We plan to measure the charge-state distributionsof 238 U at different energies in the near future.
References(b) 136Xe

10

pressure (kPa)
0.3
0.3
0.5
0.9
2.0
4.5

500

1000

Fig. 4. Most probable charge states are plotted as a function of the gas thickness. Panels (a) and (b) present
data of 238 U and 136 Xe, respectively.

obtained by changing the gas pressure in the target
cell are shown in Figs. 2 and 3, respectively. The
charge-state distribution data are fitted by a Gaussianfunction. The most probable charge state is defined- xviii -1) Y. Yano: Nucl. Instr. Meth. B 261, 1009 (2007).
2) H. Ryuto, H. Hasebe, S. Yokouchi, N. Fukunishi,
A. Goto, M. Kase, and Y. Yano: Proc. of 18th Int.
Conf. on Cyclotrons and Their Applications, Catania,
Italy, 2007, p. 314.
3) H. Hasebe, H. Ryuto, N. Fukunishi, A. Goto, M. Kase,Y. Yano: Nucl. Instr. Meth. A 590, 13 (2008).
4) H. Kuboki, H. Okuno, S. Yokouchi, T. Kishida,
H. Hasebe, N. Fukunishi, O. Kamigaito, H. Ryuto,
M. Kase, A. Goto, Y. Yano: RIKEN Accel. Prog. Rep.
42, 135 (2009).
5) T. Kishida, Y. Gono, M. Shibata, H. Watanabe,
T. Tsutsumi, S. Motomura, E. Ideguchi, X.H. Zhou,
T. Morikawa, T. Kubo, M. Ishihara: Nucl. Instr. Meth.
A 438, 70 (1999).

RIKEN Accel. Prog. Rep. 43 (2010)

Pressure-induced new magnetic phase in Tl(Cu0.985 Mg0.015 )Cl3
probed by muon spin rotation
T. Suzuki, I. Watanabe, F. Yamada,∗1 M. Yamada,∗1 Y. Ishii, T. Kawamata, T. Goto,∗2 and H. Tanaka,∗1[spin gap, impurity, crossover, magnetic order, pressure]

†

∗1
∗2

Condensed from the proceedings of ASR2009
Department of Physics, Tokyo Institute of Technology
Faculty of Science and Technology, Sophia University

Hint = ω / γµ (gauss)A(t)In impurity-introduced spin gap system Tl(Cu1−x Mgx )Cl3 ,(a) TlCu 1-xMgxCl3 (x = 0.015)
the magnetic phase transition to an ordered state is
ZF- µSRP = 3.1kbar
observed by magnetization and speciﬁc heat measure400
8.5 K(b) TlCu 1-xMgxCl3 (x = 0.015)
ments; neutron elastic scattering measurements iden8K
ZF- µSR300
tiﬁed that this impurity-induced ordered state is an
7.5 K
antiferromagnetically ordered state in which the mag7K
200
netic structure is the same as that in the case of the
6K
1)
ﬁeld-induced phase in TlCuCl3 . The inelastic neu5K
3.1 kbar100
4.0 kbartron scattering measurement revealed that a ﬁnite spin
4K
2)
0
2.3 K
gap still remains below the transition temperature .
0
2
4
6
8
10
T (K)
Imamura et al. reported a pressure-induced magnet2%
ically ordered phase by magnetization measurements
01
2
t (µs)spectra of the ZF-µSR in the hydrostatic
for x = 0.012, and concluded that the change from theFig. 1. (a) Time
impurity-induced phase to the pressure-induced phasepressure of 3.1 kbar. Solid lines are ﬁtted results. Eachis a crossover3) . The purpose of this study is to investiplot is shifted consecutively for clarity. (b) Temperaturegate the microscopic properties of the pressure-induced
dependence of Hint at 3.1 kbar and at 4.0 kbar. Dashedphase in the impurity-doped spin gap system by zeroline is a guide for the eye.
ﬁeld muon spin rotation (ZF-µSR).
Single crystals were grown from a melt by theGz (∆, t) is the static Kubo-Toyabe function. Fitted reBridgman method. µSR measurements in hydrosults are shown in Fig.1(a) as solid lines. From the ﬁtstatic pressures were carried out using a spin-polarized
ted result, the internal static magnetic ﬁeld Hint at the
double-pulsed positive decay-muon beam with an inmuon sites is deduced using the relation of ω = γµ Hint
cident muon momentum of 90 MeV/c. The samples
because implanted muon spins precess around the towere pressurized by 4 He gas pressure in a CuBe celltal magnetic ﬁeld, including the internal ﬁeld and theusing the newly installed gas-pressurized µSR setup of
external ﬁeld, at the muon sites. The deduced internal
the RIKEN-RAL Muon Facility4) .
static magnetic ﬁeld Hint = ω/γµ at the muon sites are
Figure 1(a) shows the temperature dependence ofsummarized in Fig.1(b). With decreasing temperature
the ZF-µSR time spectra in a hydrostatic pressure of
at 3.1 kbar, Hint increases monotonously, and tends
3.1 kbar. Measurements were carried out with decreasto saturate to 280 gauss around 4 K. However, Hint
ing temperature. Below 8 K, the spontaneous muondecreases to 240 gauss at 2.3 K. Similar decrease ofspin-precession is observed, which indicates the exisHint below 4 K is observed at 4.0 kbar. The decrease
tence of a coherent long-range magnetically orderedof Hint suggests an orientation of the ordered mostate. The observed transition temperature in thements, because the change of the magnetic structure
pressure of 3.1 kbar is consistent with the temperatureleads to the modiﬁcation of dipole ﬁelds at the muon
reported in the same pressure for the case of x = 0.012
sites. Thus, we speculate that a spin-reorientation
deduced from the magnetization measurement3) . In
phase transition occurs and that an oblique antiferorder to discuss the development of the internal static
romagnetic phase, which is observed at the pressure ofmagnetic ﬁeld at the muon sites which corresponds to
14 kbar in pure TlCuCl3 5) , appears in the Mg-doped
the ordered Cu-3d magnetic moment, all spectra aresystem. In the case of Mg-doped system, it is expected
analyzed using the two components function as follows:that the pressure-induced new phase would appear at
A(t) = A1 e−λ1 t cos(ωt+θ)+A2 e−λ2 t Gz (∆, t). The ﬁrst
a pressure lower than that at which it appears in theterm is the signal from the magnetically ordered region
case of pure system, because the spin gap has alreadyof samples, and the second term is that from the large
partially collapsed in space due to the Mg doping.
pressure cell and the spin-ﬂuctuating region of samples.
References
λ1 and λ2 are the muon-spin-relaxation rate of each1) M. Fujisawa et al., J. Phys. Soc. Jpn. 75 (2006) 033702.
component, and ω is the muon-spin-rotation frequency.
2) A. Oosawa et al., Phys. Rev. B 67 (2003) 184424.
3) H. Imamura et al., Phys. Rev. B 74 (2006) 064423.
4) I. Watanabe et al., Physica B 404 (2009) 993.
5) F. Yamada et al., Phys. Rev. B 78 (2008) 224405.

- xix -

RIKEN Accel. Prog. Rep. 43 (2010)

Characterization of Spin-Dependent Response of Negative Muonium (Mu−)
to Laser Induced Polarized Electrons in n-Type GaAs under Zero Field
K. Yokoyama1, K. Nagamine1,2, K. Shimomura2, H.W.K. Tom1, R. Kawakami1, P. Bakule3,
Y. M atsuda4, K. Ishida, K. Ohishi, F.L. Pratt3, I. Shiraki5 and E. Torikai5
In the field o f the spintronics, the co nsideration o f
spin-dependent exc hange scat tering of a polarized electronin ortho - m uonium (o rtho-Mu, μ+e-, a bo und state of apositive muon and an electron with the s pins aligned i n thesame direction) has bee n proposed to detect the conduction
electron s pin polarization ( CESP) i n semiconductors [1].
Recently, a feasibility study of t his m uon m ethod was
successfully carried out
instrain-free n-type Ga As
containing 3 ×1016 cm -3 Si by measuring t he c hange i n t heange in theμ+ polarization co rresponding to a chpolarization direction u nder both l ongitudinal fi elds (L F)
and zero field (ZF) [2]. In the study, CESP was induced bycircularly polarized (CP) lasers.
The muon states in doped GaAs have been studied. The
existence and pr operties of Mu − (μ+e-e-, a diam agnetic
bound state of μ+ that contains two singlet electrons) i nn-type GaAs with Si doping higher than 1016 are known [3].
Following a r eport [2 ], the prese nt measurem ent was
conducted at Port 2 of the RIKEN-RAL b y using a pulsed
4-MeV positive m uon beam. T unable l aser ligh t of awavelength of around 831 nm and a repetition frequency of
25 Hz was generated using a wi dely t unable OP O sy stem.
The lin early po larized laser output ligh t was con verted to
CP light to illumin ate the sample. A Pockel’s cell (PC) wasused fo r pu lse-to-pulse switc hing between r ight-hand C P
light (“Anti”) and left-hand CP light (“Para”). A 10 ns laser
pulse was irradiated at 0.9 μs after the muon pulse.
Asymmetry am plitudes of t he ZF “Of f” at 15 K a reknown to co rrespond to m ainly Mu − state with Gaussian
relaxation (5 .7%). Due t o sp in ex change reactio ns with
doped el ectrons i n n-GaAs, t he 1/6 c omponent of B C-Mu
(Mu at body-center si te, nearly 1 .0%) s hows e xponential
relaxation (rate; 1 μs) and that of T -Mu (Mu at tetrah edral
site, nearly 1.0%) shows a rapid relaxation (within 1 ns).
In t he Z F “ Para-Anti” ef fect (Fi g. 1), the m ajor
characteristic of the Mu − state changes with a change of CP
of t he laser irrad iation, wh ile th e BC-M u i s in sensitive t o
the l aser i rradiation. T o st udy t he Mu− response tolaser-induced CESP, th e fo llowings were in vestigated: 1)
the l aser wavelength dependence, 2 ) l aser-power
dependence of th e r esponse and 3) th e ti me-delay
characteristic of the muon response.
A cl ear wavelength dependence re flecting t he ba ndgap
characteristics was found (Fig. 1), s uggesting that t he
Mu− response was due to the laser-induced CESP.
1

Physics & Astronomy, University of California, Riverside2

Muon Science Laboratory, IMSS, KEK

3ISIS, Rutherford Appleton Laboratory

4

Arts and Science, University of Tokyo

5

Medicine and Engineering, University of Yamanashi

As seen in Fig. 2, an inverse power dependence was seenin “Para-An ti”/“Off-On”, which is con sistent with th e sp inlifetime measured in optical measurement [4]. Precise time
spectrum m easurement showed a slow ( 33(13) n s) “Para”
response, in contrast to a fast (5.5(2.6) ns) “Anti” one.
In order t o und erstand th e ob served sp in-dependentMu− response, in ad dition t o a po ssible m ultistep pro cess,the a dmixture o f t he d-states due t o sy mmetry o f t heinterstitial sit e of th e M u− state shou ld be stud iedtheoretically [5]. Work on this line is currently in progress.

[1] E. Torikai et al., Physica B 289-290 (2000) 558-562.
[2] K. Yokoyama et al., RIKEN-APR 42 (2008) 234- 235.
[3] K.H. Chow et al. Semicon. and Semmetals 51a (1997)137.
[4] J.M. Kikkawa et al., Phys. Rev. Lett. 80 (1998) 4313-4316.
[5] S. Maekawa, private communication (2009).

Fig.1. Laser wavelength dependence of the “Off-On” and“Para-Anti” effects with the μSR amplitude at t = 0. A
typical time spectrum is shown in the inset.

Fig. 2 (Upper) Laser power dependence of the “Off-On” and“Para- Anti” effects. （Lower）Laser power dependence of
normalized “Para-Anti” and “Off-On” effects- xx -C O N T E N T S
Page

GRAVURES & HIGHLIGHTS OF THE YEAR
Construction of electron accelerators ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ ⅰFormation of Nuclear “Pasta” in Supernovae ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・

iii

Numerical evaluation of gauge invariants for a-gauge solutions in open string field theory ・・・・・・・・・・・・・・・・・・

v

Localization of γH2AX Fluorescence along Tracks of Argon Beams ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ vii
α-fine structure spectroscopy for 257Lr and 259Lr ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・

ix

In-beam γ-ray spectroscopy of 32Ne ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・

xComplete Set of Deuteron Analyzing Powers for dp Elastic Scattering at
250 MeV/nucleon and Three-Nucleon Forces ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・

xi

Negative-parity excitations unique in deformed neutron-rich nuclei close to the drip line ・・・・・・・・・・・・・・・・・・・ xii
Lattice QCD study of ΛN interaction ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ xiii
W-Boson Production by Polarized p+p Collisions at √s = 500 GeV ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ xiv
Application of a Pair of Solenoid Magnets in Beam Transport Line ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ xv
Measurement of charge-state distribution of uranium and xenon beams with a gas charge
stripper ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ xvii
Pressure-induced new magnetic phase in Tl(Cu0.985Mg0.015)Cl3 probed by muon spin rotation ・・・・・・・・・・・・・・・ xix
Characterization of Spin-Dependent Response of Negative Muonium (Mu-)to Laser
Induced Polarized Electrons in n-Type GaAs under Zero Field ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ xx
I. PREFACE ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・

1

II. RESEARCH ACTIVITIES I (Nuclear-Particle Physics)
1. Nuclear Physics
Measurement of interaction cross sections of Ne Isotopes ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・

3

Inelastic scattering of 32Mg at RIBF beam energies on various targets ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・

4

Rates of production of fission fragments from a 238U beam at 345 MeV/nucleon ・・・・・・・・・・・・・・・・・・・・・・・・

5

Study on the isomer ratios of fission products of 345 MeV/u 238U ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・

6

Measurement of the (t,3He) reaction at 300 MeV/nucleon ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・

7

Angular distribution for the 8He(d,t)7Heg.s. reaction ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・

8

Breakdown of the Z = 8 shell closure in unbound 12O ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・

9

Measurement of unbound excited states of 24O ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 10
Beta decay of the proton-rich nucleus 24Si and its mirror asymmetry ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 11
Measurement on proton-proton correlation of the excited 23Al ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 12

Persistent decoupling of valence neutrons toward the drip line: Study of 20C by γ
spectroscopy ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 13
Spin-Orbit Potentials of Neutron-Rich Helium Isotopes ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 14
Elastic scattering for 60MeV 17F on 12C target ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 15Experiment to determine the g-factor of neutron-rich S isotope ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 16
Coulomb excitation of 36Ca ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 17Experimental investigation of stellar 30S(p , γ)31Cl reaction by Coulomb dissociation
method・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 18
Branching ratio of γ to particle decay in 1.6-MeV state of 23Al ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 19
Precision measurement of the hyperfine constant of 11Be+ -II ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 20
Determination of nuclear charge radii of Be isotopes by precision optical
spectroscopy of trapped ions ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 21
Development of CDCC program and its use to calculate momentum distribution inelastic breakup reaction ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 22
Measurement of reaction cross section for 11Li using solid hydrogen target ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 23
The change about the number of trapped ions in the SCRIT experiment ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 24
Proton elastic scattering by 9C beam with E/u of 290 MeV ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 25
Energy Dependence of π-/π+ Ratio Observed in In+28Si Reaction ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 26→

Study of time-reversal symmetry in 8Li using tracking detector ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 27
New neutron-deficient actinide isotopes of 234Bk and 230Am・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 28First Quantitative Study of Resonance Scattering of α-particles

Using a 21Na

Radioisotope Beam ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 29
Progress in 30S Beam Development for a Measurment of 4He(30S,p) ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 30
New measurement of resonance scattering of alpha particles on 7Li ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 31
2. Nuclear Physics (Theory)
Subsystem correlations in Coulomb breakup reaction of 6He ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 33
One-neutron removal strength of 7He into 6He using the complex scaling method ・・・・・・・・・・・・・・・・・・・・・ 34
Five-body resonances of 8He using the complex scaling method ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 35
Gamow-Teller transitions from 9;11Li to 9;11Be ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 36
Systematic study of adiabatic-energy surfaces of Be isotopes ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 37
Study of A = 7 isotiplet Λ hypernuclei with the four-body cluster model ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 38
Shell-model study of Σ-mixing in hypernuclear isotopes ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 39
Complex-scaled CDCC method for nuclear breakup reactions・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 40
Long-Range Correlations and the Quenching of Spectroscopic Factors ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 41

Contribution of core polarization for electric quadrupole moments of neutron-richnuclei in the island of inversion ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 42
Clustering and superdeformation in sd-shell region ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 43
Examination of non-monotonic shell evolution beyond N = 28 on the basis of the
β-decay of K isotopes ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 44
Shell-model description of N=Z pfg-shell nuclei ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 45
Newly developed program for the Monte Carlo shell model ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 46
Microscopic description of oblate-prolate shape mixing in proton-rich Se isotopes ・・・・・・・・・・・・・・・・・・・・ 47
Effects of Oblate-Prolate Symmetry Breaking on Triaxial Deformation Dynamics ・・・・・・・・・・・・・・・・・・・ 48
Analysis of 78Ge by generator coordinate method ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 49
Simple-model analysis of doublet bands in doubly odd nuclei ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 50
Linear Response Calculation Using Canonical-basis TDHFB with a Schematic
Pairing Functional ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 51
Finite Amplitude Method for QRPA・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 52
Chemical potential beyond quasiparticle mean field ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 53
Canonical ensemble treatments of pairing in nite systems ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 54
Top-on-top mechanism for TSD bands in even mass nuclei ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 55
SU(3) symmetry in anisotropic harmonic oscillator ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 56
Investigation of t-band in 182Os by GCM ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 57
Global fitting of pairing density functional ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 58
Mass-number dependence of total reaction cross sections in the black-sphereapproximation・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 59
Holographic Nuclei ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 60
Critical velocity of superfluid flow through single barrier and periodic potentials・・・・・・・・・・・・・・・・・・・・・・ 61
Contribution of Nuclear Reaction Data Centre to RIKEN Nishina Center ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 62
3. Hadron Physics
Gluon-Spin Contribution to the Proton Spin from the Double-Helicity Asymmetryin Inclusive π0 Production in Polarized p + p Collisions at √s = 200 GeV ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 63
Measurements of transverse single-spin asymmetry of single electrons from open
heavy flavor decays in polarized p + p collisions at √s = 200 GeV at PHENIX・・・・・・・・・・・・・・・・・・・・・・・・・・ 64
Measurement of direct photon using virtual photon method in √s = 200 GeV d+Au
collisions at RHIC-PHENIX ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 65
Azimuthal angle dependence of neutral pion suppression in√sNN = 200 GeV
Au+Au collisions at RHIC-PHENIX ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 66

Systematic Measurement ofωMesons in p+p, d+Au, and A+A Collisionsat √sNN = 200 GeV at RHIC-PHENIX・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 67
Measurement of J/ψ production in ultra-peripheral Au+Au collisions at √sNN = 200
GeV during RHIC RUN-7 ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 68
Neutron asymmetry measurement with √s=500 GeV polarized proton collision at
RHIC-PHENIX・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 69
Cosmic-ray background in PHENIX detector ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 70
Vernier Scan Method to Reduce Relative Luminosity Uncertainties ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 71
Method For Determining Relative Luminosity From Detection Probabilities ・・・・・・・・・・・・・・・・・・・・・・・・・・・ 72
Installation and Tests of the PHENIX Muon Trigger RPCs ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 73
Upgrade of PHENIX Muon Tracker Performance and Trigger Capability for Sea
Quark Polarization Measurement at RHIC・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 75
Performance evaluation of MuTRG for upgrading PHENIX muon trigger ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 76
Measurement of the interference fragmentation function in e+e− ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 77
Precision Measurements of Charged Hadron Multiplicities in e+e− Annihilation at BELLE・・・・・・・・・・・・・・・・・・・ 78
Photoproduction of Λ(1405) and Σ 0 (1385) on the proton at Eγ=1.5-3.0 GeV atSPring-8/LEPS・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 79
E906 Drell-Yan experiment at Fermilab ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 80
A proposal to study medium mass modification of φ-mesons using φ-meson boundstate in nucleus・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 81
Simulation study for the multiplicity Measurement in the Proton-Proton Collisions
at the LHC ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 82
4. Hadron Physics (Theory)
Nuclear Force from String Theory ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 83
Quark fragmentation functions in the NJL-jet model ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 84
Nucleon structure functions in 2+1-flavor dynamical DWF QCD ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 85
A first principles calculation of proton decay matrix elements・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 86
Quark masses from lattice QCD and QED ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 87
QCD phase structure in three-avor random matrix theory ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 88
Imaginary part of the real-time static potential at strong coupling ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 89
5. Particle Physics
Tenth-order QED contributions to lepton g − 2・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 91
Color Magnetic Flux Tubes in Dense QCD ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 92
Scattering of Giant Magnons in CP3・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 93

Gravitational Dual of Tachyon Condensation ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 94
Eschenburg space as gravity dual of avored N=4 Chern-Simons-matter theory ・・・・・・・・・・・・・・・・・・・・・・・・ 95
Genus-one correction to asymptotically free Seiberg-Witten prepotential fromDijkgraaf-Vafa matrix model ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 96
New Gauged Linear Sigma Models for 8D HyperKahler Manifolds and Calabi-Yau
Crystals ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 97
Light-cone gauge string field theory in noncritical dimensions ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 98
Light-cone gauge NSR strings in noncritical dimensions ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 99
Light-cone gauge superstring field theory and dimensional regularization ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 100
Vacuum structure around identity-based solutions ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 101
Lattice formulation of 2D N = (2, 2) SQCD based on B-model twist ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 102
SUSY WT identity in a lattice formulation of 2D N = (2, 2) SYM ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 103
6. Accelerator
Conversion of RFQ linac for new RIBF injector ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 105
Design and construction of drift-tube linac no.1 for RILAC2 ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 107
Design and Construction of Drift Tube Linac Caivties No. 2 and 3 for RILAC2 ・・・・・・・・・・・・・・・・・・・・・・・ 109
Construction of a new cavity for the double-rebuncher system for RRC・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 111
Construction of the RILAC2 (RIKE heavy-ion Linac 2) line ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 112
Production of highly charged U and Au ions from new RIKEN superconducting
ECR ion source with sputtering method ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 114
Status of the new superconducting ECR ion source for RIKEN RIBF ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 116
Installation of new superconducting ECR ion source in the Cockcroft-Walton highvoltage terminal ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 117
Design of Low Energy Beam Transport in New RIKEN Injector ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 119
Design of Medium Energy Beam Transport for 127 kV U35+ ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 121
Construction of MEBT (Middle-Energy Beam Transport) line and acceleration test ・・・・・・・・・・・・・・・・・・・・ 123
Fabrication of thicker carbon foils with longer lifetime ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 125
Renovation of the central region of RIKEN AVF cyclotron and results of beam
acceleration test ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 127
Possibility of formation of round beams in RIBF cyclotrons ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 129
Measurement of Magnetic Field of fRC Sector Magnets ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 131
Construction of Client System for 28GHz SC-ECRIS ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 133
Improvement of beam energy and longitudinal beam profile measurement system・・・・・・・・・・・・・・・・・・・・・ 135

Consistency in measurement of beam phase and beam intensity using lock-in
amplifier and oscilloscope systems ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 136
Radiation monitoring in the RRC and the beam distribution corridor using
ionization chambers・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 138
Water Cooling System in Accelerator for RIBF・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 140
Utilities in the RIBF experimental building ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 142
Calculation of Minimum Emittance in SR2 ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 144
Capability of SR2 as a compact synchrotron radiation source ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 145
Magnetic plasma confinement for laser ion source ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 146
Effect of plasma drift distance on high current beam production in DPIS・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 147
Particle simulation for direct plasma injection in an RFQ matching section ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 148
Design research of laser ion source for RHIC-EBIS ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 149
Laser Beam Recycler with Asymmetric Confocal Cavity ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 150
7. Instrumentation
Status of the BigRIPS and ZeroDegree Project ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 151
Upgrading the BigRIPS target chamber ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 153
Status of the Control system of BigRIPS ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 155
Testing of Beam Viewer at BigRIPS ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 156
Measurement of field maps of superconducting quadrupole and sextupole magnets ・・・・・・・・・・・・・・・・・・・ 157
Radiation-shielding system between the high-power beam dump and the second
superconducting quadrupole triplet in the first stage of BigRIPS ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 159
Pillow seal around the beam dump of the BigRIPS ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 161
Radiation measurement around the BigRIPS ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 163
Separation of RI beams using two-stage separation method in BigRIPS ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 165
CCJ Operation in 2008-2009 ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 167
SHARAQ Project: Progress in 2009 ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 169
Construction of high resolution beam line for the SHARAQ spectrometer ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 171
Focus tuning method of the high-resolution beam line for the SHARAQ
spectrometer・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 172
Focal Plane Detector System of SHARAQ Spectrometer ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 174
Development of Beamline Detectors for BigRIPS and High-Resolution Beamline・・・・・・・・・・・・・・・・・・・・・ 176
Current status of SAMURAI ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 178
Design of large-gap superconducting dipole magnet for SAMURAI
spectrometer・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 180

Front-End Electronics for SAMURAI Si Detectors ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 182
Design study of equipment in Rare-RI Ring ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 184
Simulation of Particle Trajectories for RIKEN Rare-RI Ring ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 186
Second Report on Progress of the Portable Multi-Reflection Time-of-Flight Mass
Spectrograph for SLOWRI ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 188
Status of the resonance ionization laser ion source at SLOWRI ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 190
Test report on primary beam dispersion matching at RIBF・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 191
Performance evaluation of Low-Pressure Multi-Wire Drift Chamber for RI beam ・・・・・・・・・・・・・・・・・・・・・ 192
Development of ionization chamber for superheavy elements ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 194
Power spectrum detected by ion beam core monitor ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 195
Lithium doped Glass Scintillators for Low Energy Neutron Detection・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 196
Pulse structure dependence of the proton polarization rate ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 197
New method of pulse shape analysis for segmented Ge detectors by using moments ・・・・・・・・・・・・・・・・・・ 199
PHENIX silicon vertex tracker project ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 201
Silicon Pixel Detector for PHENIX Vertex Tracker ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 202
QA test bench for the PHENIX silicon pixel detector ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 204
Development of wire bonding electrical-short checker for silicon pixel ladder in the
PHENIX vertex tracker ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 206
Quality assurance test of silicon pixel ladder for RHIC-PHENIX・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 208
Use of time-domain reflectometry for impedance measurement of fine-pitch andlow-material-budget readout bus of the PHENIX pixel detector ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 210
GEM detectors for the experiment to measure the mass modification of vector
mesons in nuclei at J-PARC ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 212
Development of a thick-GEM TPC for the J-PARC E15 experiment・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 214
Development of Cylindrical Detector System (CDS) for J-PARC E15 Experiment ・・・・・・・・・・・・・・・・・・・・・ 215
Development of a Cylindrical Drift Chambber for an experimental search for K −pp
bound states at J-PARC ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 216
Development of a Hadron Blind Detector for the J-PARC E16 Experiment ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 217
Design and Construction of Station-3 Drift Chamber for FNAL-E906 Experiment ・・・・・・・・・・・・・・・・・・・ 219
Computing and Network Environment at RIKEN Nishina Center ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 221
Time-Stamping System for RIBF experiments・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 222
Development of data acquisition system for short-time decay by using Flash ADC ・・・・・・・・・・・・・・・・・・・・ 224
Simple multichannel DAC, ADC, and interface for remote control from multiple
computers ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 226

Installation of MuTRG-MRG and DCMIF and Confirmation of Stable Operation
during Data Acquisition・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 228
III. RESEARCH ACTIVITIES II (Material Science and Biology)
1. Atomic and Solid State Physics (ions)Single-Event Transient Test Results of Control IC of Point-of-Load DC/DC
Converter ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 229
Feasibility of RI-beam-based wear analysis for industrial materials ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 230
In-beam Mössbauer experiment on stress-induced iron diffusion in silicon ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 231
Improvement in sensitivity of sensors for H 2 and toxic-gas detection by using
ePTFE irradiatad with 5-MeV/nucleon 14N beam ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 232
Irradiation-Induced Site Change of Hydrogen in Niobium ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 233
Simple simulation method for characterization of ion Coulomb crystals in a linear
Paul trap・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 234
Excitation spectrum of Au atoms in superfluid helium ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 235
2. Atomic and Solid State Physics (muon)
Installation and beam commissioning of new multi-channel μSR spectrometer"CHRONUS" and beam commissioning at RIKEN-RAL ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 237
Data Acquisition System for μSR Experiment at Port-4 of RIKEN-RAL Muon Facility ・・・・・・・・・・・・・・・・・・・・ 238
Development of a new Lyman-α laser for generation of ultraslow muons ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 239
Studies on Muon Spin Relaxation of n-Si Conduction Electrons Produced in p-GaAs
Overlayer by Lasers and Injected by Electrical Method・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 240
New Measurements of the Chemical Reaction Rate of Muonium with Stimulated
Raman-Pumped H2*(v=1) ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 241
Study on the pressure-induced charge-transfer phase transition in (C5H11)4N[FeIIFeIII(C2S2O2)3]
by means of μSR spectroscopy・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 242
Investigating the role of protons in the unusual muon-spin relaxation of single
molecule magnets ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 243
Muon-spin rotation and relaxation on the one-dimensional coordination polymer
magnet [Co(hfac)2•HNN] (HNN = hydro nitronyl nitroxide)・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 244
Zero-Field and Longitudinal-Field μSR Studies of Quasi-One-Dimensional Organic
Conductor, TMTTF2PF6・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 245
High-Pressure μSR Study of an Organic Spin-Peierls Material MEM-[TCNQ]2 ・・・・・・・・・・・・・・・・・・・・・・・・ 246
μSR study on the spin-singlet state in cluster magnet GaNb4S8 ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 247
Magnetic order of the frustrated triangular lattice antiferromagnet HCrO2 ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 248

μSR Study of Ordered Phases in Triangular Ising-like Antiferromagnets CsCoCl3
and CsCoBr3 ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 249
μSR Studies of the 2D Triangular-lattice Spin-liquid System κ-ET2Cu2(CN)3 ・・・・・・・・・・・・・・・・・・・・・・・・・・・ 250
μSR study around a quantum critical point in heavy-fermion compounds Ce2RhIn8−χSnχ ・・・・・・・・・・・・・・・・・・・・ 251
Precise investigation and re-examination of magnetism and superconductivity ofhigh-quality Fe-based superconductor, LaFeAsO1−χFχ ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 252
Effect of Pressure on the Stripe Dynamics in La2-xSr xCu1-yZnyO4 with x = 0.13 ・・・・・・・・・・・・・・・・・・・・・・・・・ 253
μSR study of iron-substitution effects on the Cu-spin dynamics in the overdoped
regime of La2-χSr χCu1−yFeyO4 ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 254
μSR study of the impurity-induced development of magnetic correlation in the
Bi-2201 high-Tc superconductor ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 255
μSR study of the vortex state above Tc in high-Tc superconductors ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 256
μSR study of the Heusler compound Ru1.9Fe0.1CrSi ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 257
ALC-μSR Investigation of Model Porphyrins ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 258
μSR study of structure-dependent electron radical dynamics in polythiophene andits derivatives ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 259
Study of dynamics of amorphous polymer by performing μSR measurements ・・・・・・・・・・・・・・・・・・・・・・・・・ 260
Diffusion of muon in hydrogen tungsten bronze ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 261
Measurement of the Mössbauer γ-rays from exotic Fe atoms produced by μ-- capture reactions ・・・・・・・・・・・・・・・・・ 262
Muon Transfer Studies in Solid D2 with Implanted Rare-Earth Ions ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 263
Progress in the analysis of muon beam density enhancement effect observed whenusing tapered tubes ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 264
3. Radiochemistry and Nuclear Chemistry
Production of an isomeric state of 261Rf by the 248Cm(18O,5n)261Rf reaction ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 265
Experiment on electrochemical oxidation of nobelium using a microchannel-electrode chip・・・・・・・・・・・・・・・・・・・・ 266
Liquid scintillation counting of 261Rf produced in 248Cm(18O,xn) reaction andpreseparated using RIKEN GARIS/gas-jet system ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 267
Anionic fluoro complex of element 105, Db・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 268
Electrochemical reduction of Europium on a tracer scale as a model experiment for
the reduction of Mendelevium ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 269
Hydroxide coprecipitation of Zr and Hf with Sm: Model experiment for thechemical study of Rf・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 270
Study of the reversed-phase chromatography of element 104, rutherfordium (Rf)with TIOA or TTA extractant ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 271

Use of solvent-extraction apparatus with microchemical chip in heavy-element
chemistry ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 272
Basic study of solvent extraction system with FIA for superheavy element
chemistry ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 273
Mutual separation of short-lived lanthanides by capillary electrophoresis ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 274
4. Radiation Chemistry and Biology
The effects of trichostatin A on DNA damage response after X-ray irradiation inhuman cells ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 275
Cell-killing effect of low dose of high-LET heavy ions (III) ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 276
Comparison of mutations of Neurospora crassa DSB repair-deficient mutants
induced by carbon-ion beam ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 277
Chronic effects of ion-beam irradiation on protonemal cells in the moss Funaria
hygrometrica ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 278
Seed hypoplasia induced by heavy-ion beam irradiation of pollen grains in
dioecious plant Silene latifolia ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 279
Effect of X-ray irradiation on the expression of DNA repair related genes in rice ・・・・・・・・・・・・・・・・・・・・・・ 280
Characterization of temperature-sensitive chlorotic mutant induced by ion beamirradiation・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 281
Identification of mutated gene induced by heavy ion beam irradiation in rice ・・・・・・・・・・・・・・・・・・・・・・・・・・・ 282
Identification of heavy-ion-beam induced DNA mutation by genetic mapping in
Arabidopsis mutant ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 283
LET-dependent effect of heavy-ion-beam mutagenesis on deletion size ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 284
C-ion-induced DNA mutations in variegated mutant Arabidopsis ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 285
Early-flowering mutants developed by heavy-ion-beam irradiation in soybean ・・・・・・・・・・・・・・・・・・・・・・・・・ 286
Induction of high-formaldehyde-absorption mutant by heavy-ion-beam irradiationin Murraya paniculata ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 287
Development of early-flowering mutant of strawberry cultivar "Satsumaotome" by
C-ion irradiation ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 288
IV. OPERATION RECORDS
1. Operation of RIBF
Operations of RIBF ring cyclotrons ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 289
RILAC operation ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 291
AVF cyclotron operation ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 293
Beam time statistics for user experiments・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 295

PAC Meetings for Nuclear Physics, and Material and Life Science ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 296
Radiation Safety Management at RIBF ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 297
Fee-based distribution of radioisotopes produced at AVF cyclotron ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 299
Operation of SRC cryogenic system ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 300
Present status of the BigRIPS cryogenic plant ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 302
Present Status of Liquid-Helium Supply and Recovery System ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 304
Improvement made to couplers used for liquid-helium supply and recovery lines (1) ・・・・・・・・・・・・・・・・・・ 306
Ⅴ. RECORDS OF LABORATORIES, GROUPS, AND TEAMS (Activities and members)
・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 309
Events in Nishina Center from January 2009 to March 2010				

Theoretical Research Division 				・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 310
Theoretical Physics Laboratory			・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 314
Theoretical Nuclear Physics Laboratory			・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 320
Strangeness Nuclear Physics Laboratory			

Sub Nuclear System Research Division 				・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 322
Radiation Laboratory			・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 329
Advanced Meson Science Laboratory			

RIKEN BNL Research Center			
・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 339
Theory Group		
・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 342
Experimental Group		

RIBF Research Division				・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 346
Heavy Ion Nuclear Physics Laboratory ・			・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 356
Radioactive Isotope Physics Laboratory			・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 360
Superheavy Element Laboratory			

Accelerator Group			Accelerator R&D Team		・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 363
・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 365
Ion Source Team		
・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 366
RILAC Team		

Cyclotron Team		・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 367
・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 368
Beam Dynamics & Diagnostics Team		
・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 370
Cryogenic Technology Team		Instrumentation Development Group			SLOWRI Team		・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 371
・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 375
Polarized RI Beam Team		
・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 378
Rare RI-ring Team		・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 380
SCRIT Team		

Research Instruments Group			・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 382
GARIS Team				BigRIPS Team・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 383
・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 385
SAMURAI Team		
・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 386
Computing and Network Team		
・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 388
Detector Team		

Accelerator Applications Research Group			・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 390
Radiation Biology Team		
・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 394
RI Applications Team		

User Liaison and Industrial cooperation Group			・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 396
User Support Office		
・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 397
Industrial Cooperation Team		
・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 398
Safety Management Group			CNS (Center for Nuclear Study, Graduate School of Science, University of Tokyo)		・・・・・・・・・・・・・・・・・・・ 400
TORIJIN (Todai-RIKEN Joint International Program for Nuclear Physics) ・		・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 405
・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 407
Ⅵ . LIST OF PUBLICATIONS & PRESENTATION				・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 491
Ⅶ . LIST OF PREPRINTS					・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 493
Ⅷ . LIST OF SYMPOSIA					・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 495
Ⅸ . LIST OF SEMINAR					・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 503
Ⅹ . AUTHOR INDEX					I. PREFACERIKEN Accel. Prog. Rep. 43 (2010)

Preface
RIKEN Accelerator Progress Report (APR) compiles
the yearly research activities conducted by thelaboratories and the groups of RIKEN Nishina Center for
Accelerator-Based Science, or simply RIKEN Nishina
Center (RNC). It also contains progress reports
submitted by the users of RI Beam Factory (RIBF) and
RIKEN Muon Facility at Rutherford Appleton
Laboratory in UK. This volume is No. 42 of APR
containing our major research activities conducted in2009.
In 2009, significant changes took place in the Nishina
Center Administration. In October 2009, Hideto En'yo
was appointed as the new director of RIKEN Nishina
Center. As a chief scientist of RIKEN since 2001, he has
spearheaded the international collaboration between
RIKEN and Brookhaven National Laboratory, and is
now in charge of all research activities at Nishina Center.
The former director, Yasushige Yano has completed theworld’s largest cyclotron at the heart of RIBF; the new
director is committed to open up this newly-born facility
for the world wide users and to produce world-classresearch results.
To achieve this, Walter Henning was invited to join
RIKEN Nishina Center as Associate Director from the
1st of April, 2010. With his distinguished career as theleader of GSI (Gesellschaft fur Schwerionenforschung)in Germany, Argonne National Laboratory in USA, andas the Chair of Nuclear Physics Program Advisory
Committee of Nishina Center, he is expected to further
promote scientific activities at RIBF and help Nishina
Center grow as a truly internationalized synergetic-use
laboratory.
On the same date, we also invited Hideyuki Sakai,
former Professor of the University of Tokyo and thechair of Japanese Experimental Nuclear Physics
Community, as the head of User Liaison and Industrial
Cooperation Group. He is asked to lead the userinterface function of Nishina Center from the community's perspective, not RIKEN’s.
Moreover, we have promoted many young researchers
to the heads of the teams to support and develop theinfrastructures and experimental equipments of RIBF.
With these major administrative changes, Nishina Centeris committed to metamorphose itself into a
synergetic-use laboratory open to the world’s
nuclear-physics community. Your support andencouragements are most appreciated.

while many experiments are ongoing with the existing
apparatuses using the world’s most powerful heavy ion
beams. One of the major news is on the electron storage
ring for SCRIT (Self-Confining RI Ion Target)
experiment.
The ring was kindly donated from
Sumitomo Heavy Industry. Previously known as
AURORA, it is now renamed as SR2, ScRit-equipped
Storage Ring. The ring was modified to have longer
straight sections for the SCRIT application, and electrons
were successfully stored in December 2009. The physics
experiment is scheduled for 2010, and in the meanwhile,
we will be promoting the use of synchrotron radiations
from SR2.
The new superconducting ECR ion source and Linear
Accelerator RILAC-II were set up in 2009 from which
we expect much higher beam intensity of uranium. An
independent operation of RILAC-I for super-heavy
element search and other low energy applications isbeing actively promoted as well.
The construction of SAMURAI, multiple-particle
spectrometer with a large acceptance, has beenproceeding smoothly. T. Motobayashi, who retired as
chief scientist, became the head of the construction teamto enhance the collaborative work among all who areinterested in this project.
Significant scientific achievements of the last year are
selected by the editorial committee of RIKEN
Accelerator Progress Report, and presented in“Frontispiece” and “Highlights of the Year”. Of all theseachievements, special attention should be given to thework on a gas charge stripper by Kuboki et al. This work
may well be a key to solve a long-standing problem ofcharge stripper in accelerating uranium and other heavy
elements. The power of the 48Ca beam was again
demonstrated by the in-beam �-ray spectroscopy of
32
Ne by Doornenbal et al. utilizing the BigRips isotope
separator, the Zero-Degree Spectrometer and the NaI(Tl)crystal array, DALI2. A special campaign for many
experiments inline using 48Ca beam is scheduled for2010 with an endorsement by the Program Advisory
Committee.
Other works covering a wide range of research fromsuper string theory to accelerator applications arecompiled in this volume. We believe such diversity andthe strategic focus on the RIBF science are and willcontinue to be the source of strength of Nishina Center
for Accelerator-Based Science.

With regard to the scientific progress of Nishina Center,outstanding achievements have been made last year. The
construction of basic experimental apparatuses is inprogress toward a full scale completion of the facility,

Hideto En'yo
Director,
RIKEN Nishina Center for Accelerator-Based Science-1-

RIKEN Accel. Prog. Rep. 43 (2010)2009/10/1

Organization Chart of Nishina Center for Accelerator-Based Science
Theoretical Research

Theoretical Physics
Laboratory
Hikaru Kawai（D.Sci）
Theoretical Nuclear
Physics Laboratory
Takashi Nakatsukasa（D.Sci）
Strangeness Nuclear Physics
Laboratory
Emiko Hiyama（D.Sci）

Sub Nuclear System

Radiation Laboratory
Hideto En'yo（D.Sci）
Advanced Meson Science
Laboratory
Masahiko Iwasaki（D.Sci）
Theory Group
President RIKEN

RIKEN BNL
Research Center
Nicholas P. Samios（Ph.D）

Nishina Center Advisory
Council

Ryoji Noyori
RBRC Scientific Review
Committee (SRC) Meeting

Experimental Group
Yasuyuki Akiba（D.Sci）

RIKEN Facility Officeat RAL
Teiichiro Matsuzaki（D.Sci）

Advisory Committee for the
RIKEN-RAL Muon Facility
RBRC Management
Steering Committee(MSC)

Larry Mclerran（Ph.D）

RIBF Research Division

Heavy Ion Nuclear
Physics Laboratory
Tohru Motobayashi（D.Sci）
Radioactive Isotope
Physics Laboratory
Hiroyoshi Sakurai（D.Sci）

Director RIKEN WAKO InstituteYoshiharu Doi

Superheavy Element Laboratory
Kosuke Morita（D.Sci）
Accelerator R&D Team
Hiroki Okuno（D.Sci）
Scientific Policy Committee

Ion Source Team
Takahide Nakagawa（D.Sci）

Program Advisory
Committee
Nishina Center for
Accelerator-Based Science
Director:Hideto En'yo（D.Sci）

RILAC Team
Accelerator Group

Coordination Committee

Osamu Kamigaito（D.Sci）

Safety Review Committee「Accelerator Development」
Akira Goto（D.Sci）

Machine Time Committee「Accelerator Operation」
Masayuki Kase

Deputy Director:[Theoretical Research]
Deputy Director:[RIBF Research]
Deputy Director:[Subnuclear System Research]
Deputy Director:

Eiji Ikezawa
Cyclotron Team
Naruhiko Sakamoto（D.Sci）
Beam Dynamics & Diagnostics Team

Nobuhisa Fukunishi（D.Sci）
Cryogenic Technology Team
Hiroki Okuno（D.Sci）
SLOWRI Team

Public Relations Committee

Michiharu Wada（D.Sci）
Polarized RI Beam Team
Instrumentation Ddevelopment
Group
Masanori Wakasugi（D.Sci）

Senior Advisor:Yasushige Yano（D.Sci）
Senior Advisor:Masayasu Ishihara（D.Sci）

Hideki Ueno（D.Sci）
Rare RI-ring Team
Masanori Wakasugi（D.Sci）
SCRIT Team
Masanori Wakasugi（D.Sci）
GARIS Team
Kouji Morimoto（D.Sci）
BigRIPS TeamToshiyuki Kubo（D.Sci）

Research Instruments Group
Toshiyuki Kubo（D.Sci）

SAMURAI TeamToshiyuki Kubo（D.Sci）
Computing and Network Team
Takashi Ichihara（D.Sci)
Detector Team
Atsushi Taketani（D.Sci）
Radiation Biology Team

Accelerator Applications ResearchGroup
Tadashi Kambara（D.Sci）

Tomoko Abe（D.Agr）
RI Applications Team
Tadashi Kambara（D.Ｓｃｉ）
User Support Office
Toshimi Suda（D.Sci）

User Liaison and Industrial
Cooperation Group
Tohru Motobayashi（D.Sci）

Masayuki Kase

「User Support」
Toshimi Suda（D.Sci）

Tadashi Kambara（D.Ｓｃｉ）「Industrial Cooperation」
Tadashi Kambara（D.Sci）
Safety Management Group
Yoshitomo Uwamino（D.Eng）-2-

Experiment Support Team
Industrial Cooperation TeamII. RESEARCH ACTIVITIES I(Nuclear-Particle Physics)

1.

Nuclear Physics

RIKEN Accel. Prog. Rep. 43 (2010)

Measurement of interaction cross sections of Ne Isotopes
T. Ohtsubo＊1, M. Takechi, M. Fukuda＊2, T. Kuboki＊3, T. Moriguchi＊4, D.Q. Fang＊5, H. Geissel＊6,
R. Chen, N. Fukuda, I. Hachiuma＊3, N. Inabe, Y. Ishibashi＊4, Y. Ito＊4, D. Kameda, Y. Kikuchi＊3, M. Lantz, Y.G. Ma＊5,
M. Mihara＊2, D. Nagae＊4, M. Nagashima＊1, H. Nakazato＊3, K. Namihira＊3, D. Nishimura＊2, T. Ohnishi, H. Ooishi＊4,
A. Ozawa＊4, K. Sakuma＊3, T. Suda, H. Suzuki＊4, T. Suzuki＊3, H. Takeda, K. Tanaka, T. Yamaguchi＊3, and T. Kubo
［BigRIPS, reaction cross section, nuclear structure, unstable nuclei］
Last year, we measured interaction cross sections (σI) of
neutron-rich neon isotopes ANe (A:28~32) to determine theroot mean square radii <rm2>1/2 of these nuclei 1). An
enhancement of radii in these nuclei compared to thesystematics of stable isotope nuclei was suggested 2).
This short note reports the successive measurements on
A
Ne (A:20~28), in addition to the previous measurementswith the aime of copmaring the <rm2>1/2 values of ANe withthose of the nuclei in the "island of inversion". The
formation of a neutron halo in heavier Ne isotopes was
expected, and a level inversion of the 1f and 2p orbitals waspredicted 3), and the evidence supporitng the existance ofthe neutron halo in 31Ne has been recently reported 4).
The experiment was performed at the Big-RIPS facility 5),
which is a part of the RI beam factory operated by the
RIKEN Nishina Center and CNS at the University of Tokyo.
A schematic drawing of the experimental setup is shown in
Fig. 1. The experimental setup is essentially the same asthat used in the previous measurement 1). We employed atransmission method to measure σI. A 48Ca primary beamwith an energy of 345 MeV/nucleon bombarded a Be
production target at F0. The intensity of the primary beam
was optimized for each isotope on the basis of the counting
rate recorded by the data acquisition system. The fragments
produced at an energy of around 250 MeV/nucleon werepre-separated at the first stage of BigRIPS. The Al
wedge-shaped degrader was placed at F1. A carbon target
with a thickness 1.8 g/cm2 or 3.6 g/cm2 was located at F5.
The incident and outgoing secondary beams were identified
at the first (F3-F5) and second (F5-F7) halves of the second
stage of BigRIPS, respectively; using the Bρ-ΔE-TOF
method. We used the standard detectors 6) at F3, F5, and F7
to identify the beams. We used the ion chamber (IC) at F3for the energy loss (ΔE) measurement of the incident beam.
We replaced the standard plastic scintillators at F5 and F7
with wider ones (240✕100 mm) having a thickness of 1
mm and 3 mm, respectively. These scintillation detectors
provided information on both TOF and ΔE.
Graduate School of Science, Niigata University
Department of Physics, Osaka University
Department of Physics, Saitama University＊4
Institute of Physics, University of Tsukuba
＊5
SINAP
＊6
GSI, Germany
＊1
＊2
＊3

-3-

An example of a particle identification plot is shown in
Fig. 2. We accumulated the data on the σI values of all Ne
isotopes; the accuracyo of the data was 1 %. Data analysis
to determine σI is now underway.
reaction target
48Ca 345MeV/uNin

Be target

Nout

20-28Ne ~250MeV/u

wedge
degrader
F3

F5
IC

PPAC

Plastic Scintillator

F7
IC

Reaction target (Carbon)

Fig. 1 Experimental setup at BigRIPS. The incident andoutgoing particles were identified by the particle detectors
at F3, F5, and F7 using the Bρ-ΔE-TOF method.

Fig. 2 Typical TOF-ΔE spectrum for the first stage ofBigRIPS.
References

1) T. Ohtsubo et al.: RIKEN Accel. Prog. Rep. 42, 5 (2008).
2) M. Takechi et al.: Nucl. Phys. A 834, 412c (2010).
3) W. Pöschl, D. Vretenar et al.: Phys. Rev. Lett. 79, 3841 (1996).
4) T. Nakamura et al.: Phys. Rev. Lett. 103, 262501 (2009).
5) T. Kubo et al .: Nucl. Instr. & Meth. in Phys. Res. B 204 , 97
(2003).
6) T. Ohnishi et al.: J. Phys. Soc. Japan 77, 083201 (2008).

RIKEN Accel. Prog. Rep. 43 (2010)

Inelastic scattering of 32Mg at RIBF beam energies on various targets
H. Scheit, K. Li,1 N. Aoi, H. Baba, P. Doornenbal, Y. Kondo, T. Motobayashi, S. Nishimura, H. Sakurai,
S. Takeuchi, Y. Togano, H. Wang,1 and K. Yoneda,[Nuclear structure, Island of Inversion, neutron-rich nuclei, in-beam γ-ray spectroscopy]
In-beam γ-ray spectroscopy of exotic nuclei produced in projectile fragmentation reactions at intermediate beam energies is an important tool for nuclear structure studies and is routinely applied at major radioactive ion beam facilities worldwide. Various experimental methods depend or beneﬁt from it,such as Coulomb excitation, few-nucleon removal reactions, direct reactions on light targets, in-elastic scattering, secondary fragmentation, and lifetime measurements (RDM, DSAM, recoil-shadow method). With
the commissioning of the RIBF not only has the intensity of available radioactive beams been increased enormously, but also the energies of the secondary beams
are much higher. Typically, secondary beam energies
were in the range from about 30 MeV/u to 100 MeV/u
at the RIPS facility, while at the RIBF beam energies above 200 MeV/u are common for light secondary
beams with, say A ≤ 50.
At this high beam energy, not only will the atomic
background increase dramatically, but also standard
analysis tools used at lower beam energies shouldbe tested and possibly adapted. For instance, theCoulomb excitation cross section to populate a collective 2+ state drops by about a factor of 4 when goingfrom 50 to 200 MeV/u, while the nuclear excitation
cross section stays nearly constant. Thus, Coulombnuclear interference eﬀects are expected to be much
more enhanced at the higher beam energies, possibly
limiting the precision of the extracted transition probabilities.
In order to study the background conditions for inbeam γ-ray spectroscopy at the RIBF and to test currently employed analysis techniques a high statistics
measurement of elastic and inelastic scattering of 32 Mg
on several targets was performed.
A primary 48 Ca beam with an average intensity of
about 10 particle nA and an energy of 345 MeV/u was
impinging on a 20 mm (3.7 g/cm2 ) thick rotating Be
target located at the F0 focus of the BigRIPS1) fragment separator. The produced secondary beams wereseparated using the standard Bρ–∆E–Bρ method employing a 15 mm thick wedge shaped Al degrader at
the F1 dispersive focus of the BigRIPS separator. The
momentum acceptance was ±3%. The beam particles were identiﬁed event-by-event using the standard∆E–TOF–Bρ method. The time of ﬂight (TOF) was
measured between two thin plastic scintillators locatedat the F3 and F7 achromatic foci (separated by a ﬂight∗1

path of about 47 m), the energy-loss was determinedwith an ion-chamber2 also located at the F7 achromatic focus and the Bρ was deduced from a position
measurement at the dispersive F5 focus of BigRIPS.
These secondary beams were then transported to theF8 secondary target position. To induce inelastic excitations a 14.1 mm (2.54 g/cm2 ) thick (natural) carbon target was used. Furthermore, plastic (CH2 ) andPb targets, resulting in about the same energy loss as
for the carbon target, were employed. The secondary
32
Mg beam with an intensity of about 1000 particles/s
had an energy of about 220 MeV/u at the center of thesecondary target. The emitted de-excitation γ rays
were detected by the DALI2 γ spectrometer2 with afull energy peak eﬃciency of about 20% and an expected resolution after correcting the large Doppler
shift of about 10% for a 1 MeV γ transition. For theparticle identiﬁcation and track reconstruction after
the secondary target the spectrometer ZeroDegree was
employed. As before, the ∆E–TOF–Bρ method wasapplied to unambiguously identify the particles eventby event.
The data taking times for the Pb, CH2 and the C targets were about 5, 3, and 2 hours, respectively, whichallowed us to collected several thousand counts in the+
885 keV peak, corresponding to the 2+
1 → 0gs tran32
sition in Mg. For the C and CH2 targets severaltransitions above 885 keV could be observed. In particular a comparison to similar data obtained at thelower beam energy of about 50 MeV/u at the RIPS
facility3) will be of interest.
The data are currently under analysis.
1) T. Kubo et al., Nucl. Instr. Meth. B 204, 97 (2003)
2) S. Takeuchi et al., RIKEN Acc. Rep. 36, 148 (2003)
3) S. Takeuchi et al., PRC 79, 054319 (2009)

Peking University, China-4-

RIKEN Accel. Prog. Rep. 43 (2010)

Rates of production of fission fragments from a 238 U beamat 345 MeV/nucleon
T. Ohnishi, T. Kubo, K. Kusaka, A. Yoshida, K. Yoshida, M. Ohtake, N. Fukuda, H. Takeda, D. Kameda, K.
Tanaka, N. Inabe, Y. Yanagisawa, Y. Gono, H. Watanabe, H. Otsu, H. Baba, T. Ichihara, Y. Yamaguchi, M.
Takechi, S. Nishimura, H. Ueno, A. Yoshimi, H. Sakurai, T. Motobayashi, T. Nakao ∗1 , Y. Mizoi ∗2 , M.
Matsushita ∗3 , K. Ieki ∗3 , N. Kobayashi ∗4 , K. N. Tanaka ∗4 , Y. Kawada ∗4 , N. Tanaka ∗4 , S. Deguchi ∗4 , Y.
Satou ∗4 , Y. Kondo ∗4 , T. Nakamura ∗4 , K. Yoshinaga ∗5 , C. Ishii ∗5 , H. Yoshii ∗5 , Y. Miyashita ∗5 , N. Uematsu∗5, Y. Shiraki ∗5 , T. Sumikama ∗5 , J. Chiba ∗5 , E. Ideguchi ∗6 , A. Saito ∗6 , T. Yamaguchi ∗7 , I. Hachimura ∗7 , T.
Suzuki ∗7 , T. Moriguchi ∗8 , A. Ozawa ∗8 , T. Ohtsubo ∗9 , M. A. Famiano ∗10 , H. Geissel ∗11 A. S. Nettleton ∗12 ,B. M. Sherrill ∗12 , S. Manikonda ∗13 , and J. A. Nolen ∗13
Unstable Nuclei, In-flight fission, nuclear reactions Be(238 U, x) E = 345 MeV/nucleon,
nuclear reactions Pb(238 U, x) E = 345 MeV/nucleon
The production rates of fission fragments from fissible beams provide important information about thereaction mechanism in fission processes. In addition,
they can be used to evaluate the performance of the RI
beam separator. In this report, we present the rates
of production of fission fragments produced by the inflight fission of 238 U beam at 345 MeV/nucleon; these
rates were obtained during experiments performed in2008 for finding new isotopes.1)
The 2008 experiment was performed using a primary238
U beam at an energy of 345 MeV/nucleon and an
average intensity of 0.22 pnA. Fission fragments emitted at an angle of around 0◦ were collected and analyzed using the BigRIPS separator.2) The particles
were identified using the magnetic rigidity, energy loss,
and time of flight values measured in the second stageof the BigRIPS separator. Details of the particle identification are presented in Ref. 1. In this experiment,
three different settings of the separator, namely, G1,
G2, and G3, were used to search for new neutron-richisotopes with atomic numbers (Z) of ∼30, ∼40, and∼50, respectively. The production targets were 5-mm
Be at G1, 3-mm Be at G2, and 1-mm Pb at G3. Other
settings are described in Ref. 1.
Figure 1 shows the production rates of fission fragments with Z ranging from 25 to 54. These fragments
were fully stripped. The upper and lower panels in
Fig. 1 show the results of the U + Be and the U + Pb

reactions, respectively. For example, the measured
production rates of 78 Ni and 132 Sn are 4 × 10−3 and1 × 103 count/s/pnA, respectively. These rates were
measured at a Bρ value that was almost 10% higher
than the Bρ value required for maximum yield. In caseof U beam with an intensity of 1 pµA, the expected
count rates of 78 Ni and 132 Sn are several counts/s and107 counts/s, respectively.
The solid lines in Fig. 1 indicate the predictions with
the LISE++ simulation.3) The production cross sections of the fission fragments were calculated using the
LISE++ code for abrasion fission and Coulomb fission calculations. A comparison of the measured andpredicted production rates showed that the measured
data were fairly well reproduced. Detailed analysis is
described in Ref. 1.

Counts/sec/pnA

32 34
U+Be
31 33 3536 38 40 42 44 46
Z=25 282930
37 39 41 43 45
48 49
26 27
47

60

130

Z=50

80
51

135

100
52

120
53

140

A

U+Pb

140

54

145

150

Fig. 1. Measured production rates, shown along with thepredictions from the LISE++ simulation (solid lines).
The upper and lower panels show the results of the
U + Be and U + Pb reactions, respectively. The measured data for fragments with Z ranging from 25 to 37
are obtained at G1, while those for fragments with Z
ranging from 38 to 49 are obtained at G2. The closed
and open circles denote even and odd Z values, respectively.

∗1

Department of Physics, The University of Tokyo
Department of Engineering Science, Osaka ElectroCommunication University∗3 Department of Physics, Rikkyo University∗4 Department of Physics, Tokyo Institute of Technology∗5 Department of Physics, Tokyo University of Science∗6 Center for Nuclear Study, The University of Tokyo∗7 Department of Physics, Saitama University∗8 Institute of Physics, University of Tsukuba∗9 Department of Physics, Niigata University∗10 Department of Physics, Western Michigan University∗11 Gesellschaft fuer Schwerionenforchung mbH∗12 National Superconducting Cyclotron Laboratory, Michigan
State University∗13 Argonne National Laboratory∗2

References
1) T. Ohnishi et al.: J. Phys. Soc. Jpn. 79, 073201 (2010).
2) T. Kubo et al.: Nucl. Instr. and Meth. B 204, 97 (2003).
3) O. B. Tarasov and D. Bazin: Nucl. Instr. and Meth. B
266, 4657 (2008).

-5-RIKEN Accel. Prog. Rep. 43 (2010)

Study on the isomer ratios of ﬁssion products of 345 MeV/u 238U
D. Kameda, T. Nakao,∗1 T. Kubo, T. Ohnishi, K. Kusaka, A. Yoshida, K. Yoshida, M. Ohtake, N. Fukuda,
H. Takeda, K. Tanaka, N. Inabe, Y. Yanagisawa, H. Watanabe, H. Otsu, Y. Kondo, Y. Gono, H. Sakurai,
T. Motobayashi, H. Baba, T. Ichihara, Y. Yamaguchi, M. Takechi, S. Nishimura, H. Ueno, A. Yoshimi,
M. Matsushita,∗2 K. Ieki,∗2 N. Kobayashi,∗3 K. Tanaka,∗3 Y. Kawada,∗3 N. Tanaka,∗3 S. Deguchi,∗3 Y. Sato,∗3
T. Nakamura,∗3 K. Yoshinaga,∗4 C, Ishii,∗4 H. Yoshii,∗4 N. Uematsu,∗4 Y. Shiraki,∗4 Y. Miyashita,∗4 T.
Sumikama,∗4 J. Chiba,∗4 E. Ideguchi,∗5 A. Saito,∗5 T. Yamaguchi,∗6 I. Hachiuma,∗6 T. Suzuki,∗6 T. Moriguchi,∗7
A. Ozawa,∗7 T. Ohtsubo,∗8 M. A. Famiano,∗9 A. Nettleton,∗10 B. Sherrill,∗10 S. Manikonda,∗11 and J. Nolen∗11[in-ﬂight ﬁssion, short-lived isomer, isomer ratio]
Table 1. Isomer ratios for the known isomers. E ∗ and I π
denote the excitation energy and the spin and parity of
the isomeric state, respectively. F and σf indicate theisomer ratio and spin cutoﬀ parameter estimated fromthe obtained isomer ratio, respectively.

Techniques based on in-ﬂight separation and identiﬁcation of nuclear reaction products at intermediate
energies provide us with a unique opportunity to study
the metastable states, i.e., isomers. The systematic
data of the isomer ratio F , deﬁned as the ratio of theyield of an isomer to the total yield of the product, isuseful information not only for designing experiments
involving the isomer but also for understanding themechanism of production reaction1) . A new-isotope
search utilizing the in-ﬂight ﬁssion of 345 MeV/u 238 U
was conducted in 20082), here, we observed a numberof known isomers along with more than ten new isomers3) . In this paper, the isomer ratios for several of
the known isomers are reported.
The isomer ratio can be expressed as F = Nm D/Np .
Np denotes the total number of particles implanted
into a aluminum stopper. For particle identiﬁcation,
the mass-to-charge ratio A/Q and the atomic number Z were evaluated using the measured magnetic
rigidity (Bρ) and time of ﬂight in BigRIPS and theenergy loss in the ionization chamber which was located 1-m upstream of the stopper. The reaction loss
in the stopper was estimated to be as large as 30%
for the isotopes with Z ∼ 30. Nm denotes the population of the isomeric state that was derived from the
γ-photo-peak counts by taking into account the detection eﬃciency4) and the total internal conversion
ratio reported in the γ-decay scheme. The isomeric γdetection eﬃciency εγ , in particular for the low energy
γ rays, depends on the position at which the particles
were implanted in the stopper due to the γ-ray attenuation eﬀect. We performed Monte-Carlo simulations(GEANT3) for evaluating this eﬀect on the basis of
the measured Bρ value and the observed beam proﬁleat the stopper. In addition, the εγ decreased by 22 %Nuclide
78
Zn
95
Kr
128
Cd
130
Cd
132
Sn

E ∗ (keV)
2673
196
2714
2130
4849

Iπ
(8+ )
(7/2+ )
(10+ )
(8+ )
(8+ )

F (%)
7.9(16)39(10)
3.0(5)
10(3)3.2(8)σf (h̄)
3.7
2.9
4.0
4.0
3.2

in the worst case from the value calibrated oﬄine; thiswas due to the prompt γ events prior to isomeric γdecay events. D is a correction factor of the in-ﬂight
decay occurring between the production target and thestopper. The Bρ settings allowed only the isomers of
the high-momentum side to be observed.
Table 1 shows several isomer ratios along with thespin cut-oﬀ parameter σf . The parameter σf represents the width of the angular-momentum distribution
P (J) of the prefragments; the distribution is expressed
as P (J) ∝ (2J + 1) exp(−J(J + 1)/2σf2 )5) . The loss of
the angular momentum of the fragment in the subsequent particle evaporation and γ emission is assumed
to be negligibly small. Then, σf is tentatively estimated using the obtained isomer ratio on the basis of
the sharp cutoﬀ model in which the value of F corresponds to the population of states with spin, higher
than the isomeric spin I 1) . The obtained values of σfare somewhat smaller than those reported in the caseof α-induced ﬁssion of 238 U5) , although more detailed
evaluation of σf is needed. Further systematic investigation is currently in progress.

Department of Physics, The University of Tokyo
Department of Physics, Rikkyo University∗3 Department of Physics, Tokyo Institute of Technology∗4 Department of Physics, Tokyo University of Science∗5 Center for Nuclear Study, The University of Tokyo∗6 Department of Physics, Saitama University∗7 Institute of Physics, University of Tsukuba∗8 Department of Physics, Niigata University∗9 Physics Department, Western Michigan University∗10 Michigan State University∗11 Argonne National Laboratory∗1

References∗21) J.M. Daugas et al.: Phys. Rev. C 63, 064609 (2001).
2) T. Ohnishi et al.: RIKEN Accel. Prog. Rep. 42, viii
(2009).
3) D. Kameda et al.: RIKEN Accel. Prog. Rep. 42, xv(2009).
4) T. Nakao et al.: RIKEN Accel. Prog. Rep. 42, 29(2009).
5) H. Naik et al.: Nucl. Phys. A 648, 45 (1999).

-6-

RIKEN Accel. Prog. Rep. 43 (2010)

Measurement of the (t, 3 He) reaction at 300 MeV/nucleon
K. Miki,∗1,∗3 H. Sakai,∗1 T. Uesaka,∗2 H. Baba,∗3 G.P.A. Berg,∗4 N. Fukuda,∗3 D. Kameda,∗3 T. Kawabata,∗5
S. Kawase,∗2 T. Kubo,∗3 K. Kusaka,∗3 S. Michimasa,∗2 H. Miya,∗2 S. Noji,∗1 T. Ohnishi,∗3 S. Ota,∗2 A. Saito,∗2
Y. Sasamoto,∗2,∗3 M. Sasano,∗1 S. Shimoura,∗2 H. Takeda,∗3 H. Tokieda,∗2 K. Yako,∗1 Y. Yanagisawa,∗3
A. Yoshida,∗3 K. Yoshida,∗3 and R.G.T. Zegers.∗6[SHARAQ, giant resonance, charge exchange reaction]
The isovector spin monopole resonance (IVSMR)
has been an important topic of interest in the studyof spin-isospin responses in nuclei1) . Since the IVSMR
is a breathing mode with spin and isospin ﬂips, it canbe related to the nuclear matter compressibility withspin and isospin degrees of freedom. In spite of the importance of the IVSMR, it has not been clearly identiﬁed, especially for the β + side. In order to identify
the IVSMR(β + ), we measured the 208 Pb(t, 3 He) and90
Zr(t , 3 He) reactions at 300 MeV/nucleon. This was
the ﬁrst physics experiment performed with the newly
constructed SHARAQ spectrometer2) .
The experiment was performed at the RIBF facility
at RIKEN. A primary α beam of 320 MeV/nucleon was
bombarded onto a 9 Be production target (thickness:d = 4 cm) installed at BigRIPS-F0. The produced tritons of 300 MeV/nucleon were achromatically a) transported along the high-resolution beam line to the secondary target installed at the pivot of the SHARAQ
spectrometer. The intensities were typically 300 particle nA for the primary beam and 1 × 107 cps for thesecondary tritons. The purity of the triton beam was
100%, since no other particle has the same momentumto-charge ratio (p/Q = 2.4 GeV/c) at the energy, because of kinematic restrictions.
The secondary targets used were 208 Pb (d =0.35 mm) and 90 Zr (d = 0.46 mm) foils for the IVSMR
measurements and a CH2 (d = 0.5 mm) foil for calibrations. The 3 He particles in the reaction products
were momentum analyzed by the SHARAQ spectrometer and counted by cathode-readout drift chambers
installed in the ﬁnal focal plane of the SHARAQ spectrometer. The diﬀerential cross sections were measured at an excitation energy of 0 ≤ Ex ≤ 70 MeV
and scattering angles of 0◦ ≤ θ ≤ 3◦ .
Figure 1 shows the measured CH2 (t , 3 He) spectra.
The left panel shows the XY spectrum measured in the
focal plane of the SHARAQ spectrometer. XFP and
YFP are proportional to the momentum and the vertical scattering angle of the 3 He particles, respectively.
Two main loci can be identiﬁed in the ﬁgure; these are
∗1
∗2
∗3
∗4
∗5
∗6
a)

12C( t ,3He)12B [g.s. (1+)]
1H( t ,3He)n1H( t ,3He)n
102

j. j.
PrPr

50
0

10

-50

200

Yield (cts)

YFP (mm)

100

160
120

㸺
0.0 㸺
㹼 θ 㹼 1.5r

x5

12C( t ,3He)12B[g.s. (1+)]

80
40

-100
-200 -100 0
100
XFP (mm)200

0-200 -100 0
100
XFP (mm)

1

200

Fig. 1. The obtained image at the SHARAQ focal plane for
the CH2 (t, 3 He) reaction [left] and its projection [right].
1.5
Yield (a.u.)

208

Pb( t ,3He)208 Tl@ 300MeV/u
0.0 0.5

1.0Preliminary

0.5
0.0
0

20
40
60
Excitation energy (MeV)

Fig. 2. Excitation energy spectrum for the 208 Pb(t, 3 He)
reaction (preliminary). See text for details.

attributed to the 1 H(t , 3 He) and 12 C(t , 3 He)12 B [g.s.]reactions. A kinematic correlation due to the recoilof target protons is nicely observed for the 1 H(t , 3 He)
reaction. A projection of this picture is shown in theright panel. From the distance between the two observed peaks, the dispersion of the SHARAQ spectrometer is determined to be 5.85 m, which is in agreement with the design value of 5.86 m. The energy resolution obtained from the 12 C(t , 3 He)12 B [g.s.] peak is
about 2 MeV (FWHM).
Figure 2 shows the 208 Pb(t , 3 He) spectrum at a scattering angle of 0◦ . Two peaks are observed around
5 MeV and 15 MeV. Although the latter is close to thepredicted position for the IVSMR, the isovector spin
quadrupole excitations are also expected to give a signiﬁcant cross section in this region. Therefore, it is
crucial to perform the multipole decomposition (MD)analysis by using the obtained angular distributions.
The data reduction for the precise MD analysis is currently in progress.
References

Department of Physics, University of Tokyo
CNS, University of Tokyo
RIKEN Nishina Center
JINA, Department of Physics, University of Notre Dame
Department of Physics, Kyoto University
NSCL, Michigan State University
The SHARAQ facility was not operated in the highresolution dispersive mode because of the requirement for
the large amount of statistics.

1) I. Hamamoto and H. Sagawa: Phys. Rev. C 62, 024319(2000).
2) T. Uesaka et al.: RIKEN Accel. Prog. Rep. 43 (2010).

-7-

RIKEN Accel. Prog. Rep. 43 (2010)

Angular distribution for the 8 He(d,t)7 Heg.s. reaction
E. Yu. Nikolskii,∗1 A. S. Denikin,∗2,∗3 A. A. Korsheninnikov, H. Otsu, H. Suzuki,∗4 K. Yoneda, H. Baba,
K. Yamada, Y. Kondo,∗5 N. Aoi, M. S. Golovkov,∗2 A. S. Fomichev,∗2 S. A. Krupko,∗2 M. Kurokawa,
E. A. Kuzmin,∗6 I. Martel,∗7 W. Mittig,∗8 T. Motobayashi, T. Nakamura,∗4 M. Niikura,∗9 S. Nishimura,
A. A. Ogloblin,∗6 P. Roussel-Chomaz,∗8 A. Sanchez-Benitez,∗7 Y. Satou,∗5 S. I. Sidorchuk,∗2 T. Suda,
S. Takeuchi, K. Tanaka, G. M. Ter-Akopian,∗2 Y. Togano,∗10 and M. Yamaguchi��
Nuclear reactions, d(8 He,t)7 He, unstable nucleiof changes in OP under projectile variation and applied
it to the case of the deuteron-induced reaction. For theﬁnal t–7 He channel, the OP for the 6 Li(3 He,3 He) system was used. Taking the spectroscopic factors (SF )SF [t = n + d] = 1.55) and SF [8 He = n + 7 He] = 4(assuming 4 neutrons in p3/2 state, see also6) ), we obtained a good description of the angular distribution
with the normalization factor of 1.4–1.5. We foundthat no normalization was needed when the parameters for the imaginary part in the exit channel wereslightly varied (within less than 10%) to ﬁt to the absolute cross section. The result of the corresponding
calculation is shown in Fig. 1 by a solid line, and theoptical parameters are given in Table 1. The obtained
OP were used to estimate the DWBA cross section forthe d(8 He,3 He)7 H reaction which was simultaneously
measured in this experiment.7)

Previously, we have reported on the measurement of
the excitation energy spectrum of 7 He nucleus in the
one-neutron d(8 He,t)7 He transfer reaction at the RIPS
facility. The reaction was studied at forward laboratory angles θlab ≈ (11◦ –22◦ ) using the 8 He 42 MeV/ubeam and a deuteron target.1) In the spectrum of tritons, a strong peak corresponding to the ground state(g.s.) of 7 He was observed. Figure 1 shows the angular distribution for the 7 Heg.s. state extracted from theexperimental data.
100dσ/ d Ω (mb/sr)

8 He(d,t) 7 He
g.s.

10

1
0

Table 1. Optical potential parameters.
d
U (r) = −V0 f (r, rV , aV ) + 4aW WD drf (r, rW , aW ),1/3−1f (r, ri , ai ) = {1 + exp[(r − ri A )/ai ]}
5

10

15

θc.m. (deg)

20

25

30

V0
rV
aV
WD
rW
aW
(MeV) (fm)(fm)
(MeV) (fm) (fm)d+8 He97.2
1.11 0.817
10.5
2.33 0.45
89.7
1.03 0.790
8.8
1.50 0.70
t+7 He*)1.30 0.750–––
n+7 Hen+d*)1.25 0.600–––*) varied to reproduce the experimental separation energy.

Fig. 1. The angular distribution for the 8 He(d, t)7 Heg.s. reaction. The error bars are statistical only. The curve isthe DWBA calculation.

The diﬀerential cross sections were analyzed with
the DWBA approach using the code DWUCK5.2) The
initial parameters of Woods-Saxon optical model potentials (OP) were obtained in two steps: (i) we performed optical model ﬁtting of the elastic scattering
data from the 8 He(p, p) reaction at Elab = 15, 26, 32.5,
66, and 72 MeV/u3) and obtained OP parameters for
Elab = 42 MeV/u by linear interpolation; (ii) by analyzing the 6 Li(p, p), 6 Li(d, d) and 6 Li(3 He,3 He) scattering data4) at 25 MeV/u, we determined the tendency

References
1) E. Yu. Nikolskii et al.: RIKEN Accel. Prog. Rep. 41, 14(2008).
2) P. D. Kunz:
Computer code DWUCK5 (1980),
http://spot.colorado.edu/∼kunz/DWBA.html.
3) A. A. Korsheninnikov et al.: Phys. Lett. B 316, 38(1993); Phys. Lett. B 343, 53 (1995); Phys. Rev. C 53,
R537 (1996); R. Wolski et al.: Nucl. Phys. A 701, 29c(2002); F. Skaza et al.: Phys. Lett. B 619, 82 (2005).
4) D. Gupta et al.: Nucl. Phys. A 674, 77 (2000);
M. Avrigeanu et al.: Nucl. Phys. A 759, 327 (2005);
T. Sinha et al.: Phys. Rev. C 47, 2994 (1993).
5) O. F. Nemets et al.: Nucleon Associations in Atomic
Nuclei and Many-Nucleon Transfer Reactions (Naukova
Dumka, Kiev, 1988) [in Russian].
6) F. Skaza et al.: Phys. Rev. C 73, 044301 (2006).
7) E. Yu. Nikolskii et al.: RIKEN Accel. Prog. Rep. 41, 15(2008).

On leave from Kurchatov Institute, Russia
Joint Institute for Nuclear Research, Russia∗3 International University ”Dubna”, Russia∗4 Department of Physics, University of Tokyo∗5 Department of Physics, Tokyo Institute of Technology∗6 Kurchatov Institute, Russia∗7 Departamento de Fisica Aplicada, Universidad de Huelva,
Spain∗8 GANIL, Caen Cedex, France∗9 Center for Nuclear Study, University of Tokyo∗10 Department of Physics, Rikkyo University

∗1

∗2

-8-

RIKEN Accel. Prog. Rep. 43 (2010)

Breakdown of the Z = 8 shell closure in unbound 12 O†
D. Suzuki,∗1,∗2 H. Iwasaki,∗1,∗2 D. Beaumel,∗2 L. Nalpas,∗3 E. Pollacco,∗3 M. Assié,∗2 H. Baba,
Y. Blumenfeld,∗2 N. De Séréville,∗2 A. Drouart,∗3 S. Franchoo,∗2 A. Gillibert,∗3 J. Guillot,∗2 F. Hammache,∗2
N. Keeley,∗4 V. Lapoux,∗3 F. Maréchal,∗2 S. Michimasa,∗5 X. Mougeot,∗3 I. Mukha,∗6 H. Okamura,∗7 H. Otsu,
A. Ramus,∗2 P. Roussel-Chomaz,∗8 H. Sakurai, J. -A. Scarpaci,∗2 O. Sorlin,∗8 I. Stefan,∗2 and M. Takechi[Nuclear structure, unstable nuclei, missing-mass spectroscopy]
We report on the missing-mass spectroscopy of unbound 12 O in the 14 O(p,t) reaction at 51 AMeV.
Mirror symmetry is a fundamental feature of atomic
nuclei. Recent experimental studies have shown thatthe conventional magic numbers disappear in neutronrich regions at N = 8, 20, and 28. Theoretical studies
point to various underlying mechanisms. The validityof the mirror symmetry of these eﬀects under extreme
conditions of isospin and binding energies remains an
open question, limiting predictions for very protonrich nuclei. We experimentally investigated the mirror
symmetry in the shell quenching phenomena between
1212
8 O4 and its mirror partner 4 Be8 .
The systematics of the low-lying excited states ineven-even nuclei provides a sensitive probe to study
the evolution of the shell structure. The anomalously
lowered excited states in 12 Be1–3) are known to be amanifestation of the breakdown of the N = 8 shellclosure. However, experimental diﬃculties have hampered the determination of a level scheme for 12 O. The
advantage of the (p,t) reaction is that the angular distributions are sensitive to the transferred angular momentum. Observations of the characteristic distributions provide a ﬁrm conﬁrmation of a new state andenable a reliable determination of its spin-parity.
In missing-mass studies using RI beams, the measurement of the energies and angles of the recoiling
particles is essential to identify the excited states ofinterest and to determine the scattering angles for thereaction. The recoiling ions generally have low energies, and this results in a severe constraint on the possible target thickness. However, in the present reaction,
which has a highly negative Q value (−31.7 MeV),
the momentum of the incoming 14 O that yields 12 O
is greatly reduced; this results in a relatively large momentum being imparted to the recoiling triton that isemitted in the forward direction. This enables us to
use a 1-mm-thick solid hydrogen target4) to increase
the experimental yield.
†
∗1
∗2
∗3
∗4
∗5
∗6
∗7
∗8

The experiment was performed at the GANIL facility. The secondary 14 O beam at 51 AMeV was produced in the SISSI device5) and delivered to the hydrogen target located in the scattering chamber of the
SPEG spectrometer.6) The incident position and incident angle on the target were monitored by two setsof multiwire low pressure chambers, CATS.7) The purity (intensity) of 14 O was around 40% (6 × 104 pps).
The ejectiles were detected by SPEG or a Si ∆E-E
telescope provided by RIKEN. The energies and angles of the recoiling tritons were measured by an arrayof four MUST2 telescopes8) located 30 cm downstreamof the target. Each telescope, with an active area of
10 × 10 cm2 , consisted of a 0.3-mm-thick double-sided
Si strip detector and a 4-cm-thick 16-fold CsI calorimeter.
The excitation energy (Ex ) spectrum was made fromthe total kinetic energy and the laboratory scattering
angle of the recoling tritons. We observed a peak at an
Ex of 1.8(4) MeV, which indicates a new excited stateof 12 O. The spin-parity of the state was determined to
be 0+ or 2+ by comparing the measured diﬀerential
cross sections with distorted-wave calculations.
The Ex of the 12 O excited state is remarkably
smaller compared to the second 0+ and ﬁrst 2+ statesof 14,16 O (Ex ∼ 6 MeV) with a ﬁrm shell closure at
Z = 8. On the other hand, it is close to the statesof 12 Be (Ex ∼ 2 MeV) with signiﬁcant neutron sdshell conﬁgurations. Thus, the lowered excited state
indicates that the proton shell closure at Z = 8 is diminishing in 12 O. This demonstrates the persistenceof mirror symmetry in the disappearance of the magic
number 8 between 12 O and 12 Be. Implications for theshell quenching mechanism were discussed in terms of
the shell model and the cluster model.
References
1) D. E. Alburger et al.: Phys. Rev. C 17, 1525 (1978).
2) H. Iwasaki et al.: Phys. Lett. B 491, 8 (2000).
3) S. Shimoura et al.: Phys. Lett. B 560, 31 (2003).
4) P. Dolégiéviez et al.: Nucl. Instrum. Methods A 564,
32 (2006).
5) A. Joubert et al.: Proceedings of the Second Conferenceof the IEEE Particle Accelerator p. 594 (1991).
6) L. Bianchi et al.: Nucl. Instrum. Methods A 276, 509(1989).
7) S. Ottini-Hustache et al.: Nucl. Instrum. Methods A
431, 476 (1999).
8) E. Pollacco et al.: Eur. Phys. J. A 25, 287 (2005).

Condensed from the article in Phys. Rev. Lett. 103, 152503(2009)
Department of Physics, University of Tokyo
Institut de Physique Nucléaire, IN2 P3 -CNRS, France
CEA-Saclay, DSM/IRFU SPhN, France
The Andrzej So�ltan Institute for Nuclear Studies, Poland
CNS, University of Tokyo
Universidad de Sevilla, Spain
RCNP, Osaka University
GANIL, CEA/DSM-CNRS/IN2P3, France-9-

RIKEN Accel. Prog. Rep. 43 (2010)

Measurement of unbound excited states of 24 O
K. Tshoo,∗1 Y. Satou,∗1 T. Nakamura,∗2 N. Aoi, H.C. Bhang,∗1 S. Choi,∗1 S. Deguchi,∗2 F. Delaunay,∗3 J.
Gibelin,∗3 T. Honda,∗4 M. Ishihara, Y. Kawada,∗2 Y. Kondo,∗2 T. Kobayashi,∗5 N. Kobayashi,∗2 F.M.
Marques,∗3 M. Matsushita,∗4 Y. Miyashita,∗6 T. Motobayashi, Y. Nakayama,∗2 N.A. Orr,∗3 H. Otsu, H.
Sakurai, S. Shimoura,∗7 D. Sohler,∗8 T. Sumikama,∗6 S. Takeuchi, K.N. Tanaka,∗2 N. Tanaka,∗2 Y. Togano, K.
Yoneda, K. Yoshinaga,∗6 T. Zheng,∗9 Z.H. Li, Z.X. Cao,∗9[ Nuclear structure, Neutron-rich nuclei, Magic number, Shell structure ]

∗1
∗2
∗3
∗4
∗5
∗6
∗7
∗8
∗9

Department of Physics and Astronomy, Seoul National University, Korea.
Department of Physics, Tokyo Institute of Technology,
Japan.
LPC Caen, ENSICAEN, Université de Caen, CNRS/IN2P3,
Caen, France.
Department of Physics, Rikkyo University, Japan.
Department of Physics, Tohoku University, Japan.
Department of Physics, Tokyo University of Science, Japan.
Department of Physics, The University of Tokyo, Japan.
Institute of Nuclear Physics (ATOMKI), Debrecen, Hungary.
School of Physics and State Key Laboratory of Nuclear
Physics and Technology, Peking University, Beijing, China.

- 10 -































Fig. 1. Schematic view of the experimental setup.

tories of the charged fragments originating from thetarget were measured using two drift chambers, MDC(Middle Drift Chamber) and FDC (Fragment Drift
Chamber), placed before and after a dipole magnet.
The nuclear charge of the fragments was determinedfrom the energy loss in the hodoscope placed just after
the FDC. The neutrons emitted during the decay of
24 ∗O were detected by a neutron-counter array placed∼4.5 m downstream from the target. The momentum
vector of the neutrons were determined from the hit
position in the neutron-counter array and the time offlight. A preliminary decay energy spectrum obtained

Changes in the magic number and shell structurethat accompany an increase in neutron or proton numbers are important factors that indicate the structuresof nuclei close to drip lines. Oxygen isotopes are theheaviest nuclei for which the neutron drip line has
been experimentally established.1) While the γ-rays
from the bound excited states of 20 O, 21 O, and 22 O
(N = 12∼14) have been identified at GANIL,2) thoseemitted from 23−24 O have not been observed. It implies that the first excited states of 23−24 O lie above
the neutron threshold. Recently, the unbound excitedstates of 23 O have been determined by the invariant
mass method at RIKEN and MSU.3,4) The first 2+ excited state of the most neutron rich oxygen isotope,
24
O, was studied by Hoffman et al.5) However, the excited state was not clearly identified. Since the position of the first 2+ excited state is one of the indicators of a magic nucleus, unambiguous identification ofthis state is essential to confirm that 24 O is a doubly
magic nucleus. In the present experiment, we investigated the unbound excited states of 24 O using the24O(p, p )24 O∗ →23 O+n reaction in inverse kinematics.
The 2+ excited state can be identified in the invariant
mass spectrum of 23 O+n. The experiment was performed at the RIPS facility operated by the RIKEN
Nishina Center. A 63 MeV/nucleon secondary beam of24
O was produced in a beryllium production target by
the fragmentation of a 95 MeV/nucleon 40 Ar primarybeam. The secondary beam was selected by magnetic
analysis in the fragment separator, RIPS, and the 24 O
beam with an intensity of ∼4 ions/s was directed towards a liquid-hydrogen target. The target thickness
was ∼160 mg/cm2 . Background measurements were
performed using an empty target cell. A schematic of
the experimental setup is shown in Fig.1. The trajec-



















Fig. 2. Preliminary decay energy spectrum of 23 O+n.

from the invariant mass of 23 O+n is shown by the open
circles in Fig. 2. The first 2+ excited state of 24 O is
expected to be identified.
References
1) M. Thoennessen: Rep. Prog. Phys. 67, 1187 (2004).
2) M. Stanoiu et al.: Phys. Rev. C 69, 034312 (2004).
3) Z. Elekes et al.: Phys. Rev. Lett. 98, 102502 (2007).
4) A. Schiller et al.: Phys. Rev. Lett. 99, 112501 (2007).
5) C. R. Hoffman et al.: Phys. Lett. B 672, 17 (2009).

RIKEN Accel. Prog. Rep. 43 (2010)

Beta decay of the proton-rich nucleus 24 Si and its mirror asymmetry†
Y. Ichikawa, T. K. Onishi,∗1 D. Suzuki,∗1 H. Iwasaki,∗1 T. Kubo, V. Naik,∗2 A. Chakrabarti,∗2 N. Aoi,
B. A. Brown,∗3 N. Fukuda, S. Kubono,∗4 T. Motobayashi, T. Nakabayashi,∗5 T. Nakamura,∗5 T. Nakao,∗1
T. Okumura,∗5 H. J. Ong,∗6 H. Suzuki, M. K. Suzuki, T. Teranishi,∗7 K. N. Yamada, H. Yamaguchi,∗4 and
H. Sakurai[Nuclear structure, Proton rich, Beta decay]
We performed β-decay spectroscopy on 24 Si to investigate the characteristic structure of proton-rich nuclei containing a weakly bound proton. We focusedon the mirror asymmetry of the Gamow-Teller transition strength B(GT). The asymmetry of B(GT) reﬂects changes in the conﬁguration of the wave function, induced by the Thomas-Ehrman (TE) shift1,2) of
the weakly bound s-wave proton. The spectroscopy
included measurements of delayed γ rays, which had
not been measured previously, as well as delayed protons3,4) using a ∆E-E method.
The experiment was performed at RIPS5) . The secondary beam of 24 Si was produced by projectile fragmentation of a 100-MeV/nucleon 28 Si beam. For the
γ-ray measurement, 0.72-mm-thick nat Ni was used as
the primary target to improve beam purity, while forthe proton measurement, 3.0-mm-thick 9 Be was usedas the target to obtain a high yield of 24 Si. The total
intensity of the secondary beam and the purity of 24 Si
were 20 (4) kcps and 1.5 (4.1) %, respectively, in thecase of the 9 Be (nat Ni) target. To measure the halflives of the detected particles, the beam was pulsedwith a duty cycle of 500 ms/500 ms (beam on/oﬀ).
The measurements of delayed γ rays and protons
were carried out using separate setups. In the γray measurement, the beam was stopped by an active stopper made of a plastic scintillator to determine the implantation number of 24 Si. The emitted
γ rays were detected using a clover-type Ge detector
equipped with BGO Compton suppressors and a plastic β veto counter. For the proton measurement, the∆E-E method, using telescopes composed of a gas ∆E
detector and silicon E detectors, was employed in order to distinguish protons from β rays. To use the gas
detector, all the setups were contained in a chamberﬁlled with 20-Torr P10 (Ar 90% + CH4 10%) gas.
By combining the results of the two measurements,
the entire decay scheme of 24 Si was reconstructed. We+
observed two β branches to the bound 1+
1 and 12 states
†
∗1
∗2
∗3
∗4
∗5
∗6
∗7

Condensed from the article in Phys. Rev. C 80, 044302(2009)
Department of Physics, University of Tokyo
Variable Energy Cyclotron Centre, India
Department of Physics and Astronomy, and NSCL, Michigan State University, USA
Center for Nuclear Study, University of Tokyo
Department of Physics, Tokyo Institute of Technology
Research Center for Nuclear Physics, Osaka University
Department of Physics, Kyushu University- 11 -

in 24 Al for the ﬁrst time. The observation of the allowed transition ﬁrmly established the spin-parity assignment for the 1+
2 state. The branching ratios to the
+
1+
and
1
stateswere determined to be 31(4)% and12
23.9(15)%, respectively. For obtaining the branchingratio to the 1+
1 state, we assumed a reference value ofthe γ-decay ratio, Iγ (24 Alm ) = 0.82(3)6) . The branching ratios to three unbound states in 24 Al, including a
new level at 6.735 MeV, were also determined for theﬁrst time. From the half-life measurement, the previously observed proton peaks3,4) were conﬁrmed tooriginate from 24 Si.
B(GT) of 24 Si was deduced for the observed allowedtransitions. Focusing on the low-lying bound states,
B(GT) values were determined to be 0.13(1) and+0.14(1) for the 1+
1 and 12 states, which were smaller
than its mirror counterparts7) by 22(11)% and 10(8)%,respectively. The asymmetry observed of B(GT) in+
the 1+
2 state and the 11 state indicated changes in
the conﬁguration of the wave function, induced by the
TE shift. To clarify the mechanism of the asymmetry from a microscopic perspective, the experimental
values of B(GT) were compared with theoretical estimates obtained using the shell model. The asymmetryof B(GT) was reproduced by the shell-model calculation with the USD Hamiltonian8) and eﬀects of the
weak binding energy, where the single-particle energyof the proton 1s1/2 orbital was lowered by 500 keV to
24
Al. Thereproduce the TE shift for the 1+
2 state inapplicability of the calculation was conﬁrmed in termsof the overall B(GT) distribution over the unboundstates in 24 Al. The calculation indicated the asymmetry of B(GT) in the 1+
1 state could be attributed tothe changes in the conﬁguration of the wave function,accompanying the lowering of the 1s1/2 orbital. As forthe 1+
2 state, changes in some amplitudes are canceled,
and in these cases, the asymmetry is not signiﬁcant.
References
1) R. G. Thomas: Phys. Rev. 88, 1109 (1952).
2) J. B. Ehrman: Phys. Rev. 81, 412 (1951).
3) S. Czajkowski et al.: Nucl. Phys. A628, 537 (1998).
4) V. Banerjee et al.: Phys. Rev. C 63, 024307 (2001).
5) T. Kubo et al.: Nucl. Instrum. Meth. B70, 309 (1992).
6) J. Honkanen et al.: Phys. Scr. 19, 239 (1979).
7) R. E. McDonald et al.: Phys. Rev. 181, 1631 (1969).
8) B. A. Brown and B. H. Wildenthal: Ann. Rev. of Nucl.
Part. Sci. 38, 29 (1988).

RIKEN Accel. Prog. Rep. 43 (2010)

Measurement on proton-proton correlation of the excited 23 Al
Y. G. Ma,∗1 D. Q. Fang,∗1 P. Zhou∗1,∗2 X. Z. Cai,∗1 J. G. Chen,∗1 W. Guo,∗1 X. Y. Sun∗1,∗2 W. D. Tian,∗1 H.
W. Wang,∗1 G. Q. Zhang∗1,∗2 X. G. Cao∗1,∗2 Y. Fu∗1,∗2 Z. G. Hu,∗3 J. S. Wang,∗3 , M. Wang,∗3 Y. Togano, N.
Aoi, H. Baba, Y. Hara,∗4 T. Honda,∗4 K. Ieki,∗4 Y. Ishibashi,∗5 Y. Itou,∗5 N. Iwasa,∗6 S. Kanno, T.
Kawabata,∗7 H. Kimura,∗8 Y. Kondo, K. Kurita,∗4 M. Kurokawa, T. Moriguchi,∗5 H. Murakami, H. Oishi,∗5 K.
Okada,∗4 S. Ota,∗7 A. Ozawa,∗5 H. Sakurai, S. Shimoura,∗7 R. Shioda,∗4 E. Takeshita, S. Takeuchi, K. Yamada,
Y. Yamada,∗4 Y. Yasuda,∗5 K. Yoneda, and T. Motobayashi 23
C( Al,p+p+21 Na)C, two-proton emission, momentum correlation

For the proton-rich nuclei, the proton decay mechanism is complicated, especially for two-protons radioactivity1) . Considering the proton-rich nucleus 23 Al
is of very interesting in many aspects2–5) , we measured
the relative momentum and opening angle of the two
protons emitted from the excited state in 23 Al. A radioactive isotope beam of 23 Al was produced and selected using RIPS facility in RIKEN Nishina Center.
The secondary 23 Al beam with an incident energy of
72 AMeV were generated by the projectile fragmentation of a 135 A MeV 28 Si primary beam on a 9 Be production target and then transported to a 12 C reaction
target. Five layers of silicon detector were arranged in
the downstream, of which the ﬁrst two layers of Si-strip(5mm width) detectors located 62 cm downstream of
the 12 C target were used to measure the emitted angleof the fragment and protons. Each Si-strip layer consists of 5×5 matrix without detectors in the four corners. Three layers of element Si detectors were used asthe ∆E-E detectors for the fragment. The plastic hodoscopes located 2.95 m downstream of the target wereused as ∆E, E and TOF detectors for protons. Most of
the protons stopped before the third layer. The particle identiﬁcation of 23 Al before the reaction target wasdone by means of Bρ-E-TOF method. After the reaction target, the heavy fragments were identiﬁed by
ﬁve layers silicon detectors combination through the∆E-E technique. Both the emitted angle and energy
loss can be obtained for the fragments. The total energy of heavy fragments can be obtained by summingover the energy loss of the ﬁve layers silicon detectors.
Clear particle identiﬁcation was got and the (21 Na+ p + p) reaction channel was picked. By the full reconstruction of 23 Al three-body decay channel, we canreconstruct the excitation energy of 23 Al based on theinvariant mass analysis. Preliminary results of relative
momentum spectrum and opening angle of the two protons in the rest frame of three-body decay system of
∗1
∗2
∗3
∗4
∗5
∗6
∗7
∗8

Shanghai Institute of Applied Physics, CAS, Shanghai
201800, China
Graduate School of the CAS, Beijing 100039, China
Institute of Modern Physics, CAS, Lanzhou 730000, China
Department of Physics, Rikkyo University, Japan
Institute of Physics, University of Tsukuba, Ibaraki, Japan
Department of Physics, Tohoku University, Japan
Department of Physics, Kyoto University, Japan
Department of Physics, University of Tokyo, Japan- 12 -

Fig. 1. Preliminary results of the relative momentum spectrum of two protons for 23 Al decays into two protons
and 21 Na (upper panel) and of the opening angle between two protons in the center of mass of decaying
system (lower panel) in diﬀerent excitation energy windows.

p+p+21 Na are presented in Fig. 1, respectively, undersome excitation energy windows. From the left to theright, it corresponds to the windows of 6.8 ≤ E ∗ ≤ 7.2,
8.0 ≤ E ∗ ≤ 8.8 and 10.5 ≤ E ∗ ≤ 15, respectively. Two
Gaussian ﬁts are plotted in the spectra. A peak inrelative momentum qpp around 20 MeV/c is observed
which dominantly corresponds to a peak in smaller
opening angular θpp around 30-60 ◦ in those excitation
windows. In the same time, another peak is observed
around qpp ∼ 40 MeV/c which dominantly corresponds
to larger θpp . Physically, the peak at 20 MeV/c of
qpp and small opening angle is consistent with the diproton emission mechanism. In contrary, the peak atlarger qpp and θpp may correspond to sequential proton
decay or three body democratic decay. More details on
the analysis are in progress.
References
1) V. I. Goldansky: Nucl. Phys. 19, 482 (1960).
2) X. Z. Cai et al.: Phys. Rev. C 65, 024610 (2002).
3) T. Gomi et al.: Nucl Phys. A 758, 761c (2005).
4) A. Ozawa et al.: Phys. Rev. C 74, 021301(R) (2006).
5) D. Q. Fang et al.: Phys. Rev. C 76, 031601(R) (2007).

RIKEN Accel. Prog. Rep. 43 (2010)

Persistent decoupling of valence neutrons toward the drip line:
Study of 20 C by γ spectroscopy†
Z. Elekes, ∗1 Zs. Dombrádi, ∗1 T. Aiba, ∗2 N. Aoi, H. Baba, D. Bemmerer, ∗3 B. A. Brown, ∗4 T. Furumoto, ∗5
Zs. Fülöp, ∗1 N. Iwasa, ∗6 Á. Kiss, ∗7 K. Kobayashi, ∗10 Y. Kondo, ∗8 T. Motobayashi, T. Nakabayashi, ∗8
T. Nannichi, ∗8 Y. Sakuragi, ∗5 H. Sakurai, D. Sohler, ∗1 M. Takashina, ∗9 S. Takeuchi, K. Tanaka, Y. Togano,
K. Yamada, M. Yamaguchi, and K. Yoneda[nuclear structure, unstable nuclei, inelastic scattering]A few years ago, the decoupling of strongly boundneutrons in heavy carbon and boron isotopes was reported1–4) ; the decoupling was observed as a reductionin the quadrupole polarization charge of the neutrons.
This suppression of the polarization charge was associated with the extended distribution of the valence neutrons5–7) detected in reaction cross-section measurements8) . This might also be accompanied by a change
in the structure of the giant quadrupole resonance inneutron rich nuclei5,6,9) .
Recently, the lifetime of the 21+ state in 16 C has
been remeasured, and the decoupling phenomenon has
been reviewed10) . However, another recent work suggests the existence of this decoupling effect11) . Here,
we report a study on neutron and proton transition
strengths and polarization charges, as investigated byinelastic scattering processes in the heavy carbon isotope 20 C, lying next to 19 C in the chart of nuclides,
which shows halo characteristics in its ground state.
Our aim is to provide further evidence that the decoupling phenomenon occurs in the carbon isotopic chain.
The experiment was carried out at RIKEN Nishina
Center, where a 20 C beam with an intensity of 10 particle/s (pps) was provided by the RIPS fragment
separator. The beam was transmitted to secondary
targets of 208 Pb and liquid hydrogen with thicknesses of 1445 mg/cm2 and 190 mg/cm2 , respectively. The reaction occurred at a mean energy of
37.6 MeV/nucleon (middle of the target) in the Pb
run and 41.4 MeV/nucleon in the 1 H run. A stackof 160 NaI(Tl) crystals, called DALI2, surrounded thetarget; thus the de-excitation γ rays emitted by theinelastically scattered nuclei could be detected. Fromthe experimental γ ray spectra, we determined the+cross sections at σ P b (0+gs → 21 ) = 35 ± 8 mb and†Condensed from the article in Phys. Rev. C 79, 011302(R)(2009)∗1 Institute of Nuclear Research of the Hungarian Academy of
Sciences, Hungary∗2 Niigata University, Japan∗3 Forschungszentrum Dresden-Rossendorf, Germany∗4 Michigan State University, USA∗5 Osaka City University, Japan∗6 Tohoku University, Japan∗7 Eötvös Loránd University, Hungary∗8 Tokyo Institute of Technology, Japan∗9 RCNP, Osaka University, Japan∗10 Saitama University, Japan- 13 -+σ pp (0+gs → 21 ) = 24 ± 4 mb for the runs involving
Pb and liquid hydrogen targets, respectively. The results were analyzed in the framework of the coupledchannel code Ecis97. This code uses standard collective form factors to calculate the inelastic cross sections. In this manner, the neutron and proton deformation lengths were determined as δn = 1.57 ±0.14 (stat) fm, δp = 0.60 ± 0.32 (stat) fm. The corresponding multipole proton and neutron transition matrix elements (Mp2 , Mn2 ) could then be calculated as Mp2
4
2
4= 7.8 +10.6−6.1 (stat) fm and Mn = 292 ±52 (stat) fm ,respectively. The validity of the phenomenological approach was further examined by performing microscopic coupled-channels (MCC) calculations involving
the use of folding model interactions along with the
AMD transition density12) ; the results of this calculation agreed well with those of phenomenological analysis. In order to analyze the effective charges, thetransition probabilities were calculated within the shellmodel. A reduction in the value of the normal polarization charges by a factor of about 0.4 was needed toreproduce the experimental trend in carbon isotopes.
The fact that the polarization charges have decreased
to less than half of the standard values indicates thatthe coupling of the valence neutrons to the core has
become weaker; or in other words, the valence neutrons decoupled to some extent from the nuclear core.
These decreased values of polarization charges could
be attributed to the extended valence neutron distribution.

References
1) H. Ogawa et al.: Phys. Rev. C 67, 064308 (2003).
2) Zs. Dombrádi et al.: Phys. Lett. B 621, 81 (2005).
3) N. Imai et al.: Phys. Rev. Lett. 92, 062501 (2004).
4) Z. Elekes et al.: Phys. Lett. B 586, 34 (2004).
5) H. Sagawa et al.: Phys. Rev. C 63, 064310 (2001).
6) H. Sagawa et al.: Eur. Phys. J. A 13, 87 (2002).
7) Y. Suzuki et al.: Phys. Rev. C 70, 051302 (2004).
8) A. Ozawa et al.: Nucl. Phys. A 691, 599 (2001).
9) H. Sagawa et al.: Phys. Rev. C 65, 064314 (2002).
10) M. Wiedeking et al.: Phys. Rev. Lett. 100, 152501(2008).
11) H. J. Ong et al.: Phys. Rev. C 78, 014308 (2008).
12) Y. Kanada-En’yo et al.: Phys. Rev. C 71, 014310(2005).

RIKEN Accel. Prog. Rep. 43 (2010)

Spin-Orbit Potentials of Neutron-Rich Helium Isotopes†
S. Sakaguchi, T. Uesaka,∗1 T. Kawabata,∗1 T. Wakui,∗2 N. Aoi, Y. Hashimoto,∗3 Y. Ichikawa, K. Itoh,∗5 M.
Itoh,∗2 H. Iwasaki,∗4 T. Kawahara,∗6 Y. Kondo,∗3 H. Kuboki, Y. Maeda,∗7 K. Miki,∗4 T. Nakamura,∗3 T.
Nakao,∗4 Y. Nakayama,∗3 S. Noji,∗4 H. Okamura,∗8 H. Sakai,∗4 Y. Sasamoto,∗1 M. Sasano, Y. Satou,∗3 K.
Sekiguchi, T. Shimamura,∗3 Y. Shimizu, M. Shinohara,∗3 K. Suda, D. Suzuki,∗4 Y. Takahashi,∗4 A. Tamii,∗8 K.
Yako,∗4 and M. Yamaguchi[Nuclear reactions, Polarized proton, Elastic scattering, Helium isotope]
Recently, much interest has been focused on spindependent interactions in unstable nuclei. In order
to investigate the spin-dependent interactions between
protons and neutron-rich He isotopes, we measured thevector analyzing power of the proton elastic scattering from 6 He and 8 He at 71 MeV/A. The experiment
was carried out using the RIKEN Projectile-Fragment
Separator (RIPS). We used a solid polarized proton
target as a secondary target; this target was speciallyconstructed for radioactive-ion-beam experiments1,2) .
The target was a 1-mm-thick single crystal of naphthalene. The averate target polarization was 11.0 ± 2.5%.
Recoil protons and scattered particles were both detected. The measured differential cross sections dσ/dΩ
and analyzing powers Ay are indicated by closed circles
in Fig. 1. The values of dσ/dΩ are consistent with theprevious data3) , which are indicated by open circles.
In order to extract the global nature of p−6,8 He interactions, our experimental data were phenomenologically analyzed by using optical model potentials. We
assumed the central and spin-orbit terms as functions
similar to Woods-Saxon function and Thomas typefunction, respectively. We used fitting code ECIS79
to determine a parameter set that reproduces thedata. The parameter set for p+6 Li elastic scattering at 72 MeV/A4) was used as the initial potential.
The dashed lines in Fig. 1 indicate the calculation performed using the initial parameters. Results obtainedusing the best-fit parameters are represented by thesolid curves. Except at backward angles, the dσ/dΩand Ay data are well reproduced.
Next, we focus on the radius and the amplitude of
the peak of the spin-orbit potential; we call the former
as “LS radius” and the latter as “LS amplitude”. Since
the spin-orbit potential is approximated by the radialderivative of density distribution, LS radius and LS
amplitude should be closely related to the radius andthe gradient, respectively, of the density distribution.
The LS radii and LS amplitudes of 6 He and 8 He are indicated by closed squares in Fig. 2. Those of neighboring even-even stable nuclei5,6) and the global opticalpotential7) are indicated by closed and open circles,
respectively. It is apparent that the LS amplitudesof 6 He and 8 He are much smaller than those of stable nuclei. Thus, the neutron-rich helium isotopes arecharacterized by remarkably shallow spin-orbit potnetials. This feature can be intuitively explained fromthe diffused density distribution of 6 He and 8 He, whose
density gradient is less than half that of 4 He.

Fig. 2. LS radii and LS amplitudes of even-even nuclei.

Fig. 1. Differential cross sections and vector analyzing powers of the p+6,8 He elastic scattering at 71 MeV/A.
∗1
∗2
∗3
∗4
∗5
∗6
∗7
∗8

Center for Nuclear Study, University of Tokyo
Cyclotron and Radioisotope Center, Tohoku University
Department of Physics, Tokyo Institute of Technology
Department of Physics, University of Tokyo
Department of Physics, Saitama University
Department of Physics, Toho University
Department of Physics, Kyushu University
Research Center for Nuclear Physics, Osaka University

References
1) T. Wakui et al.: Nucl. Instr. Meth. 550, 521 (2005).
2) T. Uesaka et al.: Nucl. Instr. Meth. 526, 186 (2004).
3) A. Korsheninnikov et al.: Nucl. Phys. A 617, 45 (1997).
4) R. Henneck et al.: Nucl. Phys. A 571, 541 (1994).
5) Y. Iseri et al.: Genshikaku Kenkyu 49 No.4, 53 (2005).
6) H. Sakaguchi et al.: Phys. Rev. C 26, 944 (1982).
7) B.A. Watson et al.: Phys. Rev. 182, 977 (1969).

- 14 -

RIKEN Accel. Prog. Rep. 43 (2010)

Elastic scattering for 60MeV 17 F on 12 C target†
G. L. Zhang,∗1 K. J. Liu,∗1 H. Q. Zhang,∗2 C. J. Lin,∗2 C. L. Zhang,∗2 G. P. An,∗2 Z. D. Wu,∗2 H. M. Jia,∗2 X. X. Xu,∗2
F. Yang,∗2 Z. H. Liu,∗2 S. Kubono,∗3 H. Yamaguchi,∗3 S. Hayakawa,∗3 D. N. Binh,∗3 Y. K. Kwon,∗4 and N. Iwasa∗5[Elastic scattering, optical potential, proton drip line]
Our knowledge of nuclei comes mainly from the experiments with nuclei in the valley of the stability. Experimentswith nuclei far from the stability-line are expected to provide tests of current nuclear structure models. In particular, light nuclei locating near the drip line may exhibit exotic phenomena, such as manifestations of halo/skin structure. Information on the nuclear structure can be extracted
from the reaction data. Among many nuclear reactions, theelastic scattering is a major channel and will provide richinformation on reaction mechanism and structures of thenuclei. It is also used to determine optical potentials which
are important inputs for any reaction studies. However,elastic scattering data for light exotic nuclei are extremely
scarce, which raises questions about accuracy and reliability of nuclear structure information extracted from thereaction studies. Because of halo/skin structures and thesmall binding energy of the last nucleon(s), the light exotic
nuclei may behave differently from stable, well-bound nuclei in reactions and reliability of simple-minded extrapolation from the systematics in stable nuclei is open to doubt.
Thus, studies of elastic scattering induced by light exotic
nuclei are of particular interest.
Study of the 17 F elastic scattering is motivated by ourinterest described above. The study of this nucleus is quite
interesting for three reasons: (i) Because of its small binding energy of 601keV, the rms radius could be significantly
larger than that of 16 O core. (ii) It has only one bound state
below the breakup threshold, (iii) its first excited state
has a halo structure.1,2) Many experiments have been performed to explore its structure and reaction mechanisms inrecent years. Elastic scattering of 17 F+208 Pb was measured
at 10MeV/nucleon,3) 98MeV and 120 MeV,4) 90.4MeV,5)
respectively. Precise data have been obtained for the elastic scattering of 17 F on 12 C and 14 N at 10MeV/nucleon.6)
In most of the above cases, the data are taken for the 208 Pb
target. The experimental data on light targets are hardly
found, except for the data on 12 C and 14 N at the energy of
10MeV/nucleon.6) Therefore the experiment was planned
to extract the optical potential of the elastic scattering for
17
F on light target at energies near Coulomb barrier.
In order to obtain the elastic scattering data at energy
near Coulomb barrier, 60MeV 17 F+12 C reaction was studied at CNS Radioactive Ion Beam separator (CRIB). The
beam intensity on the target was about 4×105 pps. A
435µg/cm2 -thick 12 C target was used. Projectile 17 F was
identified by the time of flight (TOF) method. The Position of 17 F on 12 C target was determined by using infor∗1
∗2
∗3
∗4
∗5

School of Physics and Nuclear Energy Engineering, Beihang
University, Beijing 100191, China
China Institute of Atomic Energy, Beijing 102413, China
Center of Nuclear Study, University of Tokyo, Japan
Department of Physics, Chung-Ang University, Seoul 156756, South Korea
Department of Physics, Tohoku University, Aoba, Sendai,
Miyagi 980-8578, Japan- 15 -

Fig. 1. The particle identification before target.

mation from two position-sensitive PPACs (Parallel Plate
Avalanche Counters) set in the beam line. Six sets ofE-E detector telescopes were composed of double sided
Silicon strip detectors(50mm×50mm in area)(DSSD) andsilicon detectors without strips (SSD), and covered angle
range θlab = 5◦ − 80◦ . They were symmetrically positioned
around the beam axis in order to measure efficiently theevents of 17 F elastic scattering. The distance from the target center to the strip detectors are 145 mm, 115 mm and
85 mm depending on the three angle settings. Thin E
detectors (DSSD, 65µm thickness) were placed in front of
300µm-thick E detectors (SSD). Such detector configuration allowed identification of the atomic number Z of thescattered charged particles. The emission angle of 17 F canbe determined precisely by the silicon strip detectors. We
will be able to extract precisely the angular distribution ofelastic scattering for 60MeV 17 F+12 C.
Figure 1 shows the particle identification before target.
RF1 the time when the beam particle arrives at a PPAC
relative to the radiofrequency signal from the cyclotron resonator. TOF is obtained by using the time signals of two
PPACs before target. It is shown that 17 F particles can be
identified clearly from the primary 16 O beam with a highintensity. More detailed analysis of elastic scattering for
60MeV 17 F+12 C are being done.

References
1) R. Morlock et al.: Phys. Rev. Lett. 79, 3837 (1997).
2) M. J. Borge et al.: Phys. Lett. B. 217, 25 (1993).
3) J. F. Liang et al.: Phys. Rev. C 65, 051603 (2002).
4) J. F. Liang et al.: Phys. Rev. C 67, 044603 (2003).
5) M. Romoli et al.: Phys. Rev. C 69, 064614 (2004).
6) J. C. Blackmon et al.: Phys. Rev. C 72, 034606 (2005).

RIKEN Accel. Prog. Rep. 43 (2010)

Experiment to determine the g-factor of neutron-rich S isotope
A. Yoshimi, H. Ueno, Y. Hasama,∗1 H. Iijima,∗1 Y. Ishii,∗1 Y. Ichikawa, K. Tajiri,∗2 T. Furukawa,∗1
Y.Ishibashi,∗3 D. Nagae,∗3 K. Suzuki,∗1 T. Inoue,∗1 M. Tsuchiya,∗1 H. Hayashi,∗1
M. Uchida,∗1 H. Kawamura,∗4 and K. Asahi∗1[Nuclear structure, magnetic moment, unstable nuclei]
The nuclear moments of neutron-rich 30−33 Al were
determined1–3) using the β-NMR method that involves
spin-polarized radioactive-isotope beams. We haverecently started measuring the nuclear moments ofneutron-rich nuclei with neutron number N aound 28;
several interesting phenomena indicating the disappearance of the N = 28 shell gap in Si and S isotopes
were reported from γ-spectroscopy experiments4) . The
measurement of magnetic moments is important in order to precisely understand the nuclear wave function.
The first experiment for 41 S was carried out at the
RIKEN Accelerator Research Facility in January 2010.
A beam of 41 S was produced by the fragmentation of48
Ca projectiles at an energy E = 63 A MeV impinged
on a 9 Be target having a thickness of 139 mg/cm2 .
The beam current of 48 Ca impinging on the Be target was typically 100 − 200 particle nA. The isotopeseparation of the 41 S beam was carried out using a
projectile-fragment separator RIPS (RIken Projectile
Separator), in which the emission angle θF and momentum pF of the fragment were selected so as to obtainspin-polarized secondary beam. Under the conditionof pF = p0 × (1.035 ± 0.030) and θF > 0.5◦ with a primary beam of 100 particle nA, 41 S beam from RIPS
with a purity of 44% and an intensity of 3.8 × 103 particles/s was obtained. Here, p0 represents the central
momentum of the fragment.
The 41 S beam was then transported to the final focus
and implanted into a 0.7-mm-thick CaS (Calcium Sulfide) multi-crystal stopper in the β-NMR apparatus. A
static magnetic field B0 = 500 mT was applied to thestopper in order to preserve the spin polarization. A
radio-frequency oscillating field B1 of around 1mT wasapplied to the stopper in the direction perpendicular
to B0 . From the results of solid-state NMR measurements for the stable isotope 33 S, it was observed thatthe relaxation time of 33 S in CaS was longer than inother materials5) ; hence, CaS was as the material forthe stopper.
The search of the g-factor of 41 S was performed using
the β-NMR technique. In this technique, resonance is
detected by the change in the β-ray up/down ratio R,
which is measured using plastic scintillator telescopes
located above and below the stopper. On the basis of
a double ratio R/R0 , where R0 is the β-ray up/down
∗1

∗2
∗3
∗4

Department of Physics, Tokyo Institute of Technology
Department of Physics, Osaka University
Department of Physics, University of Tsukuba
Department of Physics, Rikkyo University- 16 -

ratio when the oscillating magnetic field B1 is not applied, the resonance frequency is derived from the measured β-NMR spectrum. Since the ground-state spin
and parity of 41 S have not been determined, the shellmodel predicts the 41 S g-factor to be in the wide range
0.25 − 1.25. For this experiment, we have developed
a fast-switching LCR circuit6) in order to realize thequick and sequential application of the NMR B1 fieldwith frequencies over a wide range. This techniquemakes it possible to efficiently scan the frequencies overa wide range for g-factor in the range 0.25 − 1.25. The
g-factor search in the range g = 0.25 − 1.25 was performed for two kinds of stopper materials CaS and Si.
The analysis of the NMR spectrum is now in progress.
References
1) D. Nagae et al.: Phys. Rev. C 79, 027301 (2009).
2) H. Ueno et al.: RIKEN Accel. Prog. Rep. 42 (2009).
3) M. De Rydt et al.: Phys. Lett. B 678, 344 (2009).
4) J. Fridmann et al.: Nature 435, 922 (2006).
5) T.A. Wagler et al., J. Mag. Res. 161, 191 (2003).
6) K. Minamisono et al., Nucl. Inst. Meth. in Phys. Res.
A 589, 185 (2008).

RIKEN Accel. Prog. Rep. 43 (2010)

Yields10

50- 17 -

2

3

4

5

Ex [MeV]6

7

RIKEN Accel. Prog. Rep. 43 (2010)

Experimental investigation of stellar 30 S(p, γ)31 Cl reaction by
Coulomb dissociation method
Y. Togano, T. Motobayashi, N. Aoi, H. Baba, S. Bishop, X. Cai,∗1 P. Doornenbal, D. Fang,∗1 T. Furukawa,
K. Ieki,∗2 N. Iwasa,∗3 T. Kawabata,∗4 S. Kanno, N. Kobayashi,∗5 Y. Kondo, T. Kuboki,∗6 N. Kume,∗3
K. Kurita,∗2 M. Kurokawa, Y. G. Ma,∗1 Y. Matsuo, H. Murakami, M. Matsushita,∗2 T. Nakamura,∗5
K. Okada,∗2 S. Ota,∗4 Y. Satou,∗5 S. Shimoura,∗4 R. Shioda,∗2 K. N. Tanaka,∗5 S. Takeuchi, W. Tian,∗1
H. Wang,∗1 J. Wang,∗7 K. Yamada, Y. Yamada,∗2 and K. Yoneda
208
Pb(31 Cl,p 30 S)208 Pb, nuclear astrophysics, Coulomb dissociation

The stellar reaction 30 S(p, γ)31 Cl was studied by
Coulomb dissociation method. This reaction occurs
during the rapid proton (rp) capture process of hydrogen burning on an accreting neutron star.1) The 30 S
nucleus is a candidate for the waiting point, at which
the reaction flow temporarily stops, in the rp process.2)
As the 30 S(p, γ)31 Cl reaction proceeds, the amount of30
S decreases and thus, the reaction flow in the rp process is speeded up. Therefore, the strength of this reaction affects the resultant abundance of heavy elements
and energy production in the rp process. 31 Cl formation in the rp process mainly depends on the cross section of resonance capture to the first excited state in31
Cl (energy: 0.75 MeV).3) Thus far, direct measurements have not been made on the 30 S(p, γ)31 Cl reaction because of the short lifetime of 30 S and the small
reaction cross section. We overcome this difficulty byemploying the Coulomb dissociation method.4) With
this method, one can determine the cross section of
the relevant stellar reaction at a relatively low beam
intensity. The aim of the present study is to determine
the rate of resonance capture in 30 S(p, γ)31 Cl, whichleads to the first excited state in 31 Cl.
The experiment was performed using the RIKEN
Projectile Fragmentation Separator RIPS at the
RIKEN Nishina Center. A 31 Cl beam with an energy of 58 MeV/nucleon was produced by the fragmentation of a 115-MeV/nucleon 36 Ar beam. The31 Cl
beam bombarded a 208 Pb target whose thickness was
104 mg/cm2 . The momentum vectors of the reaction
products, i.e., the 30 S nucleus and protons, were obtained using the detectors located downstream of thetarget. The energy of 30 S and the positions of 30 S
and the protons were measured by the silicon telescope
located 62 cm downstream of the target. The timeof flight of the protons, which penetrate the silicon
telescope, was measured by the plastic scintillator hodoscope located 2.95 m downstream of the target. Details of the experimental setup are provided in Ref. 5.
∗1

∗2
∗3
∗4
∗5
∗6
∗7

Shanghai Institute of Applied Physics, CAS
Department of Physics, Rikkyo University
Department of Physics, Tohoku University
Center for Nuclear Study (CNS), University of Tokyo
Department of Physics, TITECH
Department of Physics, Saitama University
Institute of Modern Physics, CAS- 18 -

Fig. 1. Preliminary relative energy spectrum between 30 S
and proton in the Coulomb dissociation reaction of 31 Cl.
The peak at 0.45 MeV corresponds to the first excitedstate in 31 Cl at 0.75 MeV.

The relative energy between 30 S nucleus and the protons was calculated from the momentum vectors.
Fig. 1 shows the preliminary relative energy spectrum. The peaks at 0.45 MeV and 1.1 MeV, respectively correspond to the known first and second excited states in 31 Cl6) at 0.75 MeV and 1.4 MeV. The
Coulomb dissociation cross section for the first excitedstate in 31 Cl is found preliminarily to be 7 mb by assuming the detection efficiency of the 31 Cl → 30 S +pchannel to be 45%. This value is consistent with that
estimated using the known lifetime of the 31 Si mirror
level7) . The angular distribution of the scattered 31 Cl
is currently being analyzed to determine the multipolarity of the excitation.
References
1) H. Schatz et al.: Phys. Rev. Lett. 86, 3471 (2001).
2) J. L. Fisker et al.: Asrtophys. J. 608, L61 (2004).
3) C. Iliadis et al.: Astrophys. J. Suppl. Ser. 134, 151(2001).
4) G. Baur et al.: Nucl. Phys. A458, 188 (1986).
5) Y. Togano et al.: RIKEN Accel. Prog. Rep. 42, 11(2009).
6) L. Axelsson et al: Nucl. Phys. A634, 475 (1998).
7) C. Iliadis et al: Astrphys. J. Suppl. Ser. 134, 151 (2001).

RIKEN Accel. Prog. Rep. 43 (2010)

Branching ratio of γ to particle decay in 1.6-MeV state of 23 Al
T. Honda,∗1 Y. Togano, K. Okada,∗1 Y. G. Ma,∗2 N. Aoi, H. Baba, X. Cai,∗2 J. Chen, ∗2 D. Fang,∗2 W. Guo,∗2
Y. Hara,∗1 Z. Hu,∗3 K. Ieki,∗1 Y. Ishibashi,∗4 Y. Itou,∗4 N. Iwasa,∗5 S. Kanno, T. Kawabata,∗6 H. Kimura,∗7
Y. Kondo, K. Kurita,∗1 M. Kurokawa, T. Moriguchi,∗4 H. Murakami, H. Oishi,∗4 S. Ota,∗6 A. Ozawa,∗4 H.
Sakurai, S. Shimoura,∗6 R. Shioda,∗1 E. Takeshita, S. Takeuchi, W. Tian,∗2 K. Yamada, Y. Yamada,∗1
H. Wang,∗2 J. Wang,∗7 K. Yoneda and T. Motobayashi, 23C( Al,p 22 Mg)C, nuclear structure

We carried out the inelastic scattering of 23 Al on
a C target to investigate the structure of the excitedstate in 23 Al. Emission of 1618-keV γ rays was observed from the 7/2+ state in 23 Al; the energy of theseγ rays was 1.5 MeV higher than the one-proton separation energy of 23 Al (141 keV2) ). On the basis of theshell-model calculations, Gade et al. suggested thatthe 7/2+ state of 23 Al consists of 22 Mg(2+ ) and a d5/2
proton and estimated the branching ratio between theγ decay to the 23 Al ground state and the particle decay to 22 Mg(2+ ) and proton (Γγ /Γp ) to be 201) . The
aim of the present study is to determine the branchingratio between the γ decay and the particle decay in the1618-keV state of 23 Al.
Experiments were performed using the RIKEN Projectile Fragmentation Separator RIPS at the RIKEN
Nishina Center. The present study was carried out as aby-product of the experiment performed to determine
the momentum correlation function for 23 Al3) . A secondary 23 Al beam at 72 MeV/nucleon was produced by
the fragmentation of a 135-MeV/nucleon 28 Si beam on
a 9 Be target. The 23 Al beam was made to bombard
a 355-mg/cm2 C target. The momentum vectors of
the reaction products, 22 Mg nuclei and protons, were
measured by the silicon telescope and plastic scintillator hodoscope located downstream of the target. Theenergy of the de-excitation γ-rays emitted from 22 Mg
was measured using DALI24) . Details of the experimental setup are described in Ref. 5. The relative
energy between 22 Mg and the proton was obtained byusing the invariant mass method.
Figure 1 shows the relative energy spectrum of 22 Mg
and the proton coincident with the de-excitation γ
ray from the first 2+ state in 22 Mg at 1274 keV. The
Doppler-corrected γ-ray energy spectrum obtained for22
Mg is given in the inset. In the γ-ray spectrum, deexcitation of the γ ray from the 2+ state at 1274 keV to
the ground state and from 4+ state at 3308 keV to the2+ state was observed. The relative energy spectrum
was obtained by gating the 1274-keV peak. In the rel∗1

∗2
∗3
∗4
∗5
∗6
∗7

Department of Physics, Rikkyo University
Shanghai Institute of Applied Physics, CAS
Institute of Modern Physics, CAS
Department of Physics, Tukuba University
Department of Physics, Tohoku University
Center for Nuclear Study (CNS), University of Tokyo
Department of Physics, University of Tokyo- 19 -

Fig. 1. Relative energy spectrum between 22 Mg and proton
coincident with the de-excitation γ ray from the first 2+
state of 22 Mg at 1274 keV. The Doppler-corrected γ-ray
energy spectrum of 22 Mg is shown in the inset.

ative energy spectrum, a peak at around 250 keV wasobserved; this peak corresponded to the 23 Al(7/2+ )→ 22 Mg(2+ ) + p channel. The cross section of thischannel was preliminarily calculated to be 0.1 mb, byassuming the detection efficiencies of DALI2 and thebreakup event to be 16.6% and 50%, respectively. By
combining the cross section of the γ decay channel fromthe 7/2+ state to the ground state6) , we determined
the branching ratio Γγ /Γp to be 23. This value wasconsistent with that predicted theoretically by Gadeet al. Further analysis for the branching ratio is now
in progress.
References
1) A. Gade et al.: Phys. Lett. B 666, 218 (2008).
2) A. Saastamoenen et al.: Phys. Rev. C 80, 044330(2009).
3) Y. G. Ma et al.: RIKEN Accel. Prog. Rep. 43, (2010).
4) S. Takeuchi et al.: RIKEN Accel. Prog. Rep. 39, 63(2006).
5) T. Honda et al.: RIKEN Accel. Prog. Rep. 42, 12(2009).
6) K. Okada: Master thesis, Rikkyo University, 2009.

RIKEN Accel. Prog. Rep. 43 (2010)

Precision measurement of the hyperﬁne constant of 11 Be+ -II
A. Takamine, M. Wada, K. Okada∗1 , T. Nakamura, T. Sonoda, P. Schury∗2 , H. Iimura∗3 , Y. Yamazaki,
Y. Kanai, T. M. Kojima, T. Kubo, S. Ohtani∗4 , I. Katayama∗5 , H. Wollnik∗6 , and H. A. Schuessler∗7[neutron halo, magnetization radius, laser spectroscopy]

Table 1. Resonance frequencies ν 0 for diﬀerent magnetic
ﬁelds.
Icoil [A]
5
14
30
∗1
∗2
∗3
∗4
∗5
∗6
∗7

B [mT]
0.23813(16)0.69627(26)1.504448(18)ν 0 [MHz]
2677.31134(12)2677.37430(10)2677.63430(13)

900
850
800
counts / bin

To study the electromagnetic properties of the oneneutron halo nucleus 11 Be by using the nuclear-modelindependent probe of optical spectroscopy, we havemeasured the hyperﬁne constants of radioactive Be isotope ions in an on-line ion trap. The purpose of thestudy, the method used in the study, and part of theresults have been described elsewhere.1–3) Here, we report recently obtained results of the precision measurement of the ground-state hyperﬁne constant of 11 Be+ ;this measurement is 30 times more accurate than ourprevious measurement.3)
A unique feature of 11 Be+ in comparison with 7 Be+
and 9 Be+ is that the upper hyperﬁne structure (hfs)level (F = 0) does not split because the nuclear spin I
is 1/2. If one can accommodate a fraction in the F = 0
state, one can measure the frequency of the transition(F, mF ) = (0, 0) ↔ (1, 0), a 0-0 transition that is ﬁeld
independent to the ﬁrst order. We evaluated the population of the ground-state hfs levels of Be isotopes using incompletely polarized radiation, σ + with a small
percentage of σ − . We observed that only in the caseof 11 Be+ a noticeable fraction of the population was inthe (F, mF ) = (0, 0) state even with a small mixtureof depolarized-radiation. Under this pumping condition, resonant microwave radiation at ν 0 induces the
0-0 transition, and resonance can be detected from anincrease in the ﬂuorescence intensity.
A typical microwave resonance spectrum of the 0-0transition of 11 Be+ obtained by considering the ﬂuorescence intensity as a function of the applied microwave frequency is shown in Fig. 1. The Rabi oscillation observed in this spectrum can be attributed
to 76-µs pulsed microwave radiation. The transition
frequency was determined by a least-square ﬁt to the
Rabi transition probability function.

750
700
650
600
550

340

360

380

400

420

Microwave Frequency [kHz] - 2677 MHz

Fig. 1. Typical laser-microwave double resonance spectrumof the ground state hfs transition (F, mF )=(0,0)→(1,0)
for 11 Be+ ﬁr a magnetic ﬁeld B of 0.69627(26) mT.

The ﬁeld-independent 0-0 transition still shows athe small quadratic dependence on the magnetic ﬁeld,
as indicated by the Breit-Rabi formula, which can be
written as follows:√ν 0 (B) = A2 + B 2 gJ2 µ2B (1 − γ)2 ,(1)where A is the magnetic hfs constant; B, the magnetic ﬁeld strength; gJ , the atomic g-factor; µB , theBohr magneton; and γ, the g-factor ratio. We measured ν 0 for three diﬀerent magnetic ﬁelds, as listed
in Table 1. The ﬁeld strengths were determined fromthe hyperﬁne splittings of 9 Be+ ions under the same
conditions. The resonance frequencies were ﬁtted toEq. (1), and the hyperﬁne constant was determined tobe A11 = 2677.302988(72) MHz.
The present study provides important data for the
study of the magnetization radius of the one-neutron
halo nucleus 11 Be by taking into consideration the
Bohr-Weisskopf eﬀect.4–6) We need high-precision nuclear g-factor data for all odd Be isotopes to complete
the study. A unique method to determine the nuclear
g-factors of odd Be isotopes is to measure the Zeeman splittings of the hfs for a high magnetic ﬁeld. We
have demonstrated the measurement method for stable9
Be+ ions7) and are preparing to apply it to radioactive isotopes.
References
1) K. Okada et al.: Phys. Rev. Lett. 101, 212502 (2008).
2) A. Takamine et al.: Eur. Phs. J. A 42, 369 (2009).
3) M. Wada et al.: RIKEN Accel. Prog. Rep. 42, 17 (2009).
4) A. Bohr and V. F. Weisskopf: Phys. Rev. 77, 94 (1950).
5) T. Fujita et al.: Phys. Rev. C 59, 210 (1999).
6) Y. Parfenova and Ch. Leclercq-Willaim: Phys. Rev. C
72, 024312 (2005).
7) T. Nakamura et al.: Opt. Comm. 205, (2002) 329.

Department of Physics, Sophia University
Institute of Physics, Tsukuba University
Japan Atomic Energy Research Association
ILS, University of Electro-Communications
Institute of Particle and Nuclear Studies, KEK
II. Physikalisches Institute, Justus-Liebig-Universitaet
Department of Physics, Texas A&M University- 20 -

RIKEN Accel. Prog. Rep. 43 (2010)

Determination of nuclear charge radii of Be isotopes by precision
optical spectroscopy of trapped ions
A. Takamine, M. Wada, T. Sonoda, T. Nakamura, K. Okada∗1 , P. Schury∗2 , H. Iimura∗3 , Y. Yamazaki,
Y. Kanai, T. M. Kojima, T. Kubo, S. Ohtani∗4 , I. Katayama∗5 , H. Wollnik∗6 , and H. A. Schuessler∗7

∗1
∗2
∗3
∗4
∗5
∗6
∗7

Department of Physics, Sophia University
Institute of Physics, Tsukuba University
Japan Atomic Energy Research Association
ILS, University of Electro-Communications
Institute of Particle and Nuclear Studies, KEK
II. Physikalisches Institute, Justus-Liebig-Universitaet
Department of Physics, Texas A&M University- 21 -

0.2
0.2

0.8
0.8

0.19
0.19

0.7
0.7

0.2
0.2

0.24
0.24
0.220.22

0.5
0.5

0.17
0.17

0.26
0.26

0.18
0.18

0.6
0.6

0.18
0.18

0.16
0.16

0.4
0.4

0.2 0.2
0.180.18

0.14
0.14

0.16
0.16

0.3
0.3
0.160.16
0.15
0.2
0.12
0.15
0.2
0.12
-500 -300-300 -100-100 100
100 300
300 -400-400 -200-200 0 0 200
200 400
400 -400-400-200-200 0 0 200200400400500500700 700900 90011001100-500
13001300

frequency[MHz][MHz]
frequency[MHz]frequency
frequency[MHz] frequency[MHz]frequency[MHz][MHz]
frequency[MHz]frequency-957-957 348
348 000
000MHzMHz -957
428428000000
MHz
-957
MHz
414
000
MHz
-957
414
000
MHz -957-957397
397000000MHzMHz -957

Fig. 1. Spectra of the probe transition for Be isotopes.
Be
[fm]
BeRMS
RMS Nuclear
Nuclear Charge Radii [fm]Precision optical spectroscopy experiments fortrapped ions have been performed at the prototype
SLOWRI facility of RIKEN1–5) with the aim of studying the nuclear charge radii of Be isotopes. The isotope
shifts of optical transition frequencies have been used
to determine the nuclear charge radii of radioactive
nuclei in a nuclear-model-independent manner6) . However, for very light elements such as Be, the shift due
to the nuclear volume is as small as 10 MHz, whereas
the optical transition energy is about 109 MHz and theeﬀect due to the diﬀerent mass is about 103 MHz. We
need precise theoretical results7) to subtract the massdependent contribution from the isotope shifts as wellas to measure the absolute transition frequencies witha relative accuracies of over 10−9 .
In previous reports,3,4) we presented the measurement results for the 2s 2 S1/2 (smaller F )-2p 2 P3/2 transition frequencies obtained by the optical-optical double resonance spectroscopy with the 2 2S1/2 (largest F )2 2P3/2 transition for cooling and detection of the resonance. However, in this study, we noticed that there
are several possible transitions for the probe transition
due to the occurrence of Zeeman splitting, and further, that the probability of each transition strongly
depends on the optical-pumping condition. We observed noticeable ﬂuctuation in the transition frequencies in systematic measurements.
In order to avoid such ambiguities, the same transition as the cooling transition was measured using aweak probe laser (0.2 µW) for a short period of 14µs, while a strong cooling laser (170 µW) was used
to irradiate for 5.6 µs so that the ion temperature remains low. Fast and sharp switching of the coolinglaser was carried out by an AOM device. The probelaser frequency was measured simultaneously with thephoton-counting data using a frequency comb system
and a beat frequency counting system, which was constructed in-house.8) The resonance frequencies were
determined from the thus obtained Lorentzian shape
spectra (Fig. 1), and the frequencies at the center ofthe gravity in case of the 2s 2S1/2 → 2p 2P3/2 transition were deduced after taking into account the com-

LIF
LIF signal
signalcounts
counts/bin/bin[neutron halo, charge radius, laser spectroscopy, ion trap]

Laser-Cooled
Trapped Ions
Ions@
@RIKEN
RIKEN
Laser-Cooled Trapped
Collinear Laser
Laser Spectroscopy
Spectroscopy@@ISOLDEISOLDE

2.8
2.8

2.6
2.6

2.4
2.4

2.2
2.2

66

77

88

99
10
10
Mass
Mass Number
Number

11
11

12
12

Fig. 2. Preliminary evaluated charge radii of Be isotopes.

pensation required for due the hyperﬁne and Zeeman
splittings. The results for 7,9,10,11 Be+ were 957 347
372.0(1.2) MHz, 957 396 618.7(0.6) MHz, 957 413
945.1(0.9) MHz, and 957 428 188.9(2.9) MHz, respectively. The large discrepancy between the results for
11
Be+ obtained in the present study and that obtainedin a previous one3) is mainly attributed to the incomplete cooling condition as a results of the large hyperﬁne splitting of 11 Be+ .
Although the analysis is still in progress, the charge
radii of Be isotopes obtained from preliminary evaluation are shown in Fig. 2 along with the results ofthe collinear-laser spectroscopy experiment performedby the COLLAPS group at ISOLDE9) . There are noticeable discrepancies between our results of the absolute frequencies and those obtained by the COLLAPS group. However, the values of isotope shifts
agree within the margin of errors.
References
1) T. Nakamura et al.: Phys. Rev. A 74, 052503 (2006).
2) K. Okada et al.: Phys. Rev. Lett. 101, 212502 (2008).
3) A. Takamine et al.: RIKEN Accel. Prog. Rep. 42, xiv(2009).
4) A. Takamine et al.: Eur. Phys. J. A 42, 369 (2009).
5) M. Wada et al.: Hyp. Int. 196, 43 (2010).
6) E. W. Otten: in Treatise on heavy-ion science,
D. A. Bromley (Ed.), 8, 517 (1989).
7) Z. -C. Yan et al.: Phys. Rev. Lett. 100, 243002 (2008)8) M. Wada et al.: RIKEN Accel. Rep. 42 191 (2009).
9) W. Nöertershäuser et al.: Phys. Rev. Lett. 102, 062503(2009).

RIKEN Accel. Prog. Rep. 43 (2010)

Development of CDCC program and its use to calculate momentum
distribution in elastic breakup reaction
Yasuo Aoki, Tohru Motobayashi, and Akira. Ozawa,∗1
A computer program hctak.f, which is based on
the continuum discretized coupled channels(CDCC)1)
idea, was developed. It aims at calculating S matrix elements of a scattering process involving loosely boundprojectile and a hard target. The whole system is assumed to composed of three particles and are named
as 1, 2 and 3. The Hamiltonian H of the system iswritten as,of the work by Beunerd et al.,5) . Nucleon optical potential is well established, but that of heavy ions areunder developing stage.
The following figure compares 22 Mg momentum distribution measured at 0◦ . Dots are the experimental
ones, red and blue curves are due to s (d)-state groundstate wave functions.
0.25
0.25

Al+ C

H = T12 + T(1+2)−3 + V12 + V13 + V23 .

Department of Physics, Tsukuba University- 22 -dσ/d(cP)dσ/d(cP) [mb/MeV][mb/MeV]0.2
0.2

T’s in the above expression are kinetic energies andV’s are interaction potentials among particles, which
are specified by the suffices. Optical potentials are
assumed for these potentials.
The function of the program are 1) calculate boundand scattering state wave functions of 1-2 system,
whose Hamiltonian is given by T12 + V12 , 2) expand
the potentials V13 + V23 into multipoles and evaluate
the matrix elements of these potentials, 3) construct
a set of coupled equation for given angular momentum and parity, and solve this coupled equation withproper boundary conditions, and 4) calculate S matrix
elements corresponding to elastic scattering and many
break up channels.
Resulting S matrix elements may be used to evaluate many physical observable, like differential crosssections of elastic scattering, double and triple differential cross sections of break up processes, momentum
distribution in the fragmentation reaction.
The reaction 23 Al+12 C with EAl = 1.702 GeV2) was
taken as the first case to apply this newly developed
analysis method. The projectile 23 Al is assumed toconsists of a proton and a 22 Mg. The binding energy
is reported to be 125 keV, and the spin and parity J πof the system is reported3) to be 5/2+ . To save cpu
time, intrinsic spin of nucleons are suppressed. To see
the structure dependence of the projectile, two calculations are performed, one with d-state and the otherwith s-state as the ground state wave function. Scattering states of proton-22 Mg system(1-2 system) are
generated by assuming a real central potential, which
reproduce the bound state energy and a resonant sstate located about 500 keV above the ground state.
These scattering states are truncated to have orbital
angular momenta of s, p, d, f and g waves and the
maximum wave numbers of 2.0 fm−1 . This wave number span is divided into 20 bins. Interaction potentials
between proton and 12 C, V13 , is taken from the literature4) , while that of 22 Mg and 12 C, V23 is the set F
∗1

23
12
23Al+ 12C

0.15
0.15

=1.702 GeV
E
EAl
Al=1.702 GeV

ddx x0.9
0.9
ssx x0.33
0.33

0.1
0.1
0.05
0.05
00

7800
7900 8000
8000 8100
8100 8200
8200 8300
8300 8400
8400 8500
8500 8600
8600
7800 7900
cP[MeV]
cP [MeV]d-state wave function reproduces the experimental
width better than that of the s-state. Absolute magnitude of the calculated results are scaled to fit into
the figure. Total reaction cross section is reported2)
to be 1609 mb, while the present calculation predicts
1271(1305) mb for d(s)-state of the 22 Mg. We canadjust the relatively ambiguous optical potential of22
Mg+12 C to reproduce the magnitude of total reaction cross section, at the cost of reduced intensity ofthe momentum spectrum. ¿From this experience, improved optical potential is highly requested.
Many thanks are due to computation services offeredby riken integrated cluster of clusters(ricc).
References
1) M. Kamimura, et al., Prog. Theor. Phys. Jpn. Suppl.
89(1986) 1
2) D. Q. Fang et al., Phys. Rev. C76,031601(R)(2007)
3) A. Ozawa et al., Phys. Rev. C74,021301(R)(2006)4) B. A. Watson, P. P. Singh and R. E. Segel, Phys. Rev.
182, 977(1969)5) M. Beunerd et al., Nucl. Phys. A424, 313(1984)

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Measurement of reaction cross section for 11 Li
using solid hydrogen target
T. Moriguchi,∗1 A. Ozawa,∗1 H. Suzuki,∗1 Y. Ito,∗1 H. Ooishi,∗1 Y. Ishibashi,∗1 Y. Abe,∗1 S. Ishimoto,∗2
T. Suzuki,∗3 T. Yamaguchi,∗3 T. Kuboki,∗3 I. Hachiuma,∗3 K. Namihira,∗3 M. Fukuda,∗4 D. Nishimura,∗4
T. Suda, M. Takechi, M. Lantz, K. Tanaka, and T. Ohtsubo∗5[reaction cross section, nuclear structure, unstable nuclei, solid hydrogen target]

∗1
∗2
∗3
∗4
∗5

Institute of Physics, University of Tsukuba
High Energy Accelerator Research Organization
Department of Physics, Saitama University
Department of Physics, Osaka University
Graduate School of Science, Niigata University

0.26 g/cm2 . A Kapton foil with a thickness of 25 µm
was used at the entrance and exit windows of the SHT
cell. The entrance of the cell, which was in a vacuum
chamber connected to the exit of the F3 chamber, waslocated 1741 mm downstream of the end of the triplet
Q-magnet in F3. A 127-µm-thick Mylar foil was used
for the vacuum window, downstream of the SHT. ∆E
and the total kinetic energy (E) of the particles ejectedfrom the reaction target were detected by two silicondetectors (100 × 10 0 × 0.3 mm3 ) and a NaI(Tl) detector (φ5” × 60 mmt ), respectively. The ∆E-E method
was used for the identiﬁcation of the outgoing particles. We also performed an experiment using a carbon
target and an empty cell and compared the obtained
result with the earlier result1) . In this case, the carbon target (0.505 g/cm2 ) was installed immediately
after the vacuum window in air. σR can be deduced
from the ratio of the number of incident particles to thenumber of outgoing particles. The analysis to deduce
σR is now in progress.
SHT Vacuum window

CD-PPACSSD
11Li

NaI(Tl)C-target
Plastic
scintillator

SSD

Fig. 1. Experimental setup at F3.

Energy Loss [MeV]

The reaction cross section (σR ) for 11 Li has beenmeasured by using a solid hydrogen target (SHT). The
purpose of this experiment is to deduce the skin thickness by combining the σR value with the carbon target1) without directly measuring of the charge radiusby optical isotope shift measurements. If this new
method is successful, it can be used to deduce theskin thickness of nuclei such as 78 Ni, on which optical isotope shift measurements cannot be performed.
In this method, we performed the σR measurementson hydrogen and carbon targets, which have diﬀerent
sensitivities to the densities of protons and neutrons.
We have previously developed a thick SHT for use in
the σR measurement of unstable nuclei2) .
The experiment was performed using the RIKEN
Projectile Fragment Separator (RIPS). A primarybeam of 18 O was accelerated up to 100 MeV/nucleon
in the RIKEN Ring Cyclotron. A secondary beam
was produced by bombardment of the 18 O beam on
a Be target (10 mmt ). 11 Li particles with an energyof 45 MeV/nucleon were separated by the RIPS. In
the dispersive focal plane (F1), an energy degrader of2683 mg/cm2 Al was installed, and a horizontal slitdeﬁned the momentum acceptance as ±0.5%. Figure
1 shows the experimental setup in the ﬁnal focal plane(F3). Identiﬁcation of the incident particles before
the reaction target was performed by the Bρ-TOF∆E method (Fig. 2), where Bρ, TOF, and ∆E referto the magnetic rigidity, time of ﬂight, and energy loss.
The TOF between the achromatic focal plane (F2) andF3 was measured by 0.5-mm-thick plastic scintillators.
∆E was measured by a 150-µm-thick silicon detector(SSD) placed in F3. The typical yield and purity of
11
Li were 800 cps and 60%, respectively. The positionof the beam at the target surface was determined bythree sets of parallel-plate avalanche counters (PPACs)
placed upstream of the target. High eﬃciency wasachieved even for low-Z nuclei such as 11 Li by employing a charge division readout instead of the delay-line
readout that is normally used in the RIPS.
The volume of the SHT in this experiment was φ50mm × 30 mmt , which corresponded to approximately

12

Be
11

Li

9

Li
8

8

Li

He

6

He

3

H

F2- F3 TOF [ns]Fig. 2. Identiﬁcation of the incident particles before thereaction target by the Bρ-TOF-∆E method.

References
1) Inabe et al.: RIKEN Accel. Prog. Rep. 24, 9 (1990).
2) T. Moriguchi et al.: RIKEN Accel. Prog. Rep. 42, 185(2008).

- 23 -

1

RIKEN Accel. Prog. Rep. 43 (2010)

The change about the number of trapped ions in the SCRIT experimentS. Wang, T. Suda, T. Emoto, K. Kurita1, T. Tamae2, M. Wakasugi and Y. Yano
In the SCRIT experiment, ions trapped by an electron beam microseconds and extracted[3], as shown in Fig.3. The
in an electron storage ring are used as nuclear target for electron background measurement was done for the successive 50
scattering experiment. In the R&D experiment using 133Cs ions, microseconds without ion injection. Those 18 cycles are defined
the number of trapped ions and their charge-to-mass ratio were as cycle number from 1 to 18. Each cycle included with andmeasured by an analyzer[1], which consists of an electrode, a without Cs ions injection.
magnet and nine channeltrons, as shown in Fig.1. Luminosity ofion-electron scattering was determined from a luminosity
monitor[2] by measuring small scattering angle electrons.

Fig. 3: Time sequence of the measurement.
During the 2 seconds measurement, the luminosity and thenumber of trapped ions were increased at small cycle numbers

Fig.1 Position of analyzer and luminosity monitor.

The luminosity determined by luminosity monitor and the and became stable at large cycle numbers, as shown in Fig.4.
number of trapped ions at different beam currents are shown in Due to radiation damping, electron beam shrunk to small size
Fig.2. Both of them increase with beam currents from 40 mA. gradually and became stable, after being injected into storage
This may cause by deeper trapping potential of the electron ring. This mechanism can be thought to cause larger luminosity
and the higher number of trapped ions at large cycle numbers. In

beam at larger beam current.

60

6

40

4

20
40

45

50 55 60 65
beamcurrent (mA)

70

25

0

25

5

2

experiment.

-2

80

8

select the optimum measurement period in the future SCRIT

160

20

140

15

100

120

-1

10

number 10. Therefore, we can use similar figure like fig.4 toluminosity (10 s cm )

-2 -1
25

100

0
75

Fig.2: Luminosity and the number of trapped ions at different
beam currents.
seconds in order to keep a large beam current at 80 mA and the60luminosity
number of trapped ions

5
0

0

2

4

40
20

0
6 8 10 12 14 16 18
cycle number

5Electron beam was injected into storage ring every 480

10number of trapped ions (10 )luminosity (10 cm s )luminosity
number of trapped ions12Fig.4, the electron beam seemed to become stable around cycle
number of trapped ions (10 )

120

14

measurement started at 2 seconds after beam injection. During

Fig.4: Luminosity and the number of trapped ions at different

the 2 seconds measurement, ions were injected, trapped for 50

cycle numbers.

*1 Rikkyo University*2 Tohoku University

1) M. Wakasugi, et al.: Phys. Rev. Lett. 100, 164801 (2008).
2) S. Wang, et al.: RIKEN Accel. Prog. Rep. 41 (2008).
3) T. Suda, et al.: Phys. Rev. Lett. 102, 102501 (2009).

- 24 -

RIKEN Accel. Prog. Rep. 43 (2010)

Proton elastic scattering by 9 C beam with E/u of 290 MeV
Y. Matsuda,∗1 T. Kobayashi,∗1 S. Terashima,∗2 H. Sakaguchi,∗3 J. Zenihiro,∗3 H. Takeda, H. Otsu, K. Yoneda,
K. Ozeki, Y. Satou,∗4 T. Murakami,∗5 and M. Kanazawa∗6[Nuclear structure, Proton elastic scattering, Unstable nuclei]

∗1

∗2
∗3
∗4
∗5
∗6

Department of Physics, Tohoku University
GSI, Darmstadt, Germany
Department of Physics, Osaka University
Department of Physics and Astronomy, Seoul National University, Korea
Department of Physics, Kyoto University
Department of Accelerator and Medical Physics, NIRS,
Chiba, Japan- 25 -

proton and neutron density distributions for the RMF,
respectively, while the long dashed-dotted and the dotted lines show those for the AMD. The proton and neutron density distributions calculated by using the RMF
theory and the AMD were found to be different of thesurface of the solid-hydrogen target. The RMF density
distribution suggests that there might be a large difference between the proton and neutron radii, whichare 2.58 fm and 2.06 fm, respectively. In conclusion,
the obtained data indicates that 9 C has a proton skin.
10 3
H(9C, p)9C

10 2

Obtained data
Reference data [3]RIA+RMF
RIA+AMD

10 1
10 0
10 -1
10 -2
5

10

15

20

25

30

35

40

45

Fig. 1. The differential cross sections for H(9 C,p) reaction
compared with 12 C data. Results of the theoretical calculations (described in the text) are also plotted.

Density [ fm-3]

Size and density distribution are the fundamental
properties of nuclei and have been experimentally andtheoretically studied. Proton elastic scattering at intermediate energies can be used to study these properties and has been analyzed for medium–heavy stable nuclei by using relativistic impulse approximation(RIA).1) However, experimental data available on the
proton elastic scattering of unstable nuclei are limited
because of the experimental difficulties.
In order to confirm the substantial variation in thematter distribution in carbon isotopes that has been
predicted by various theoretical models, we studied forthe first time the proton elastic scattering at intermediate energies using a 9 C beam with E/u of 290 MeV
which was extracted from the HIMAC synchrotron at
NIRS.2) Since 9 C has no bound excited states, proton
elastic scattering by the 9 C beam can be feasibly studied by using a 5 mm thick solid-hydrogen target, drift
chambers, plastic scintillators, and NaI(Tl) calorimeters. In addition, due to the large difference between
the proton number (6) and the neutron number (3) of
9
C, we can expect 9 C to have a large proton skin.
In Fig. 1, we show the experimentally observed angular distribution of proton elastic scattering from 9 C
represented by circles along with that from 12 C represented by squares, which is considered to be the reference data.3) The diffraction pattern obtained for 9 C issmoother than that for 12 C.
Since in the case of light nuclei, the RIA cannot givea precise explanation of the scattering process, andtherefore, it becomes difficult to deduce the nuclear
matter density, we compared the qualitatively calculated results of scattering for different density distributions. In Fig. 1, the solid and the dashed lines
show the results obtained for the density distributions
given by the relativistic mean field (RMF) theory1) andby the antisymmetrized molecular dynamics (AMD)4) ,respectively. Since the RIA tends to underestimate
the scattering at backward angles, a comparatively
smoother diffraction pattern is reproduced for the density distributions given by the RMF theory than for
those given by the AMD. Figure 2 shows the density
distributions. The solid and the dashed lines show the

10-1

p (RMF)n (RMF)
p (AMD)n (AMD)

10-2
10-3
10-4
10-50

1

2

3

4

5

6
7
8
Radius [fm]Fig. 2. Proton and neutron density distributions of 9 C calculated by using the RMF theory and the AMD.

References
1) C. J. Horowitz et al.: in Computational Nuclear Physics
1, edited by Steven E. Koonin (Springer-Velag, Berlin,1991), Chapter 7.
2) S. Terashima et al.: RIKEN Accel. Prog. Pep. 40, 18(2007).
3) H. O. Meyer et al.: Phys. Rev. C 37, 544 (1988).
4) Y. Kaneda-En’yo and H. Horiuchi: Prog. Theor. Phys.
Suppl. 142, 647 (2001).

RIKEN Accel. Prog. Rep. 43 (2010)

Energy Dependence of π − /π + Ratio Observed in In+28 Si Reaction
T. Murakami,∗1 Y. Ichikawa,∗1 S. Imajo,∗1 M. Sako,∗1 R. Sameshima,∗1 E. Takada,∗2 K. Ieki,∗3
M. Matsushita,∗3 J. Murata,∗3 Y. Nakai, S. Nishimura, and H. Sakurai[Symmetry energy, pion ratio, high density]
The density dependence of nuclear symmetry energy Esym (ρ) is one of the hottest topics not only inboth nuclear physics but also in astrophysics. It is
predicted that detailed studies of Y(π − ) /Y(π + ) yieldratios in central nucleus-nucleus collisions at intermediate energies would provide significant constraints on
the Esym (ρ) at high densities ρ > ρ0 1) . For last three
years we have been developing a compact centrality filter and a pion range counter in order to measure theY(π − ) /Y(π + ) yield ratios. This year we have modified our pion range counter by inserting additional two
5 mm thick plastic scintillators and a 10 mm thick one
in between the second (2 mm) and third (15 mm) elements of its 2008’s version2) . By this addition we could
improve its identification-power for low energy pions.
Following the successful application of both the centrality filter and the range counter to the In(132 Xe,π ± )reaction at E/A = 400 MeV last year3) , we have performed a series of experiments using 400, 600, and 800
MeV/nucleon 28 Si beams accelerated at HIMAC. A
typical intensity was 5×106 ppp and a target thickness
was 330 mg/cm2 . Using the range counter π + eventswere clearly identified by selecting double pulse signals
corresponding to π + → µ+ + νµ decays after stop at
one of its elements. Since most of negative pions arecaptured by carbon atoms in the scintillator to trigger
an instantaneous disintegration of a carbon nucleus,
only positive pions generate double pulse. A total
number of charged pions was, then, estimated by using ∆Ei -∆Ej correlations empirically determined for
π + events. It turned out that four or more ∆E detectors are needed to sufficiently suppress the backgroundarising from protons. Signals from the range counter
were processed by a FPGA module, QDC’s and multihit TDC’s and then accumulated by a Linux PC. A
charged particle multiplicity from the centrality filter
was also recorded by event by event basis.
Figure 1 shows π + energy spectra obtained for
In+28 Si reaction at E/A = 400 MeV. They have beencorrected for various effects; decay in flight, nuclear
reactions of pions in the range counter, and multiple
Coulomb scattering. Currently only statistical errors
are included though we expect 10% order overall uncertainties for the absolute values. Only smooth change
in shape was observed as a function of the angle. We
have not yet finalized π − energy spectra since we still
∗1

∗2
∗3

Department of Physics, Kyoto University, Kyoto, Japan
Department of Accelerator and Medical Physics, NIRS,
Chiba, Japan
Department of Physics, Rikkyo University, Tokyo, Japan- 26 -

need to work out the efficiency of ∆Ei -∆Ej correlation
gates for the charged pion extraction.

Fig. 1. Double differential cross section for π + productions
with 400A MeV 28 Si on In.

Preliminary results of Y(π − ) /Y(π + ) yield ratios estimated for the pions at 90◦ in the laboratory system
are shown as a function of transverse momentum ofpions in Fig.2. The three ratios for three different incident beam energies are almost identical at this angle
despite we expected to see some increase of the ratio as
the incident energy approaches to the pion thresholdenergy. Further analysis of the data is in progress.

Fig. 2. Preliminary results of Y(π − ) /Y(π + ) yield ratios
at 90◦ in the laboratory system for In+28 Si collisions
at various incident energy/nucleon.

References
1) Bao-An Li, Gao-Chan Yong, and Wei Zuo, Phys. Rev.
C 71 (2005) 014608.
2) T. Murakami et al., RIKEN Accel. Prog. Rep. 41 (2009)28.
3) T. Murakami et al., Nucl. Phys. A 834 (2010) 593c-595c(NN2009 proceedings).

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

� using tracking detector
Study of time-reversal symmetry in 8 Li
H. Kawamura,∗1 T. Akiyama,∗1 J.A. Behr,∗2 M. Hata,∗1 Y. Hirayama,∗3 Y. Ikeda,∗1 T. Ishii,∗4 D. Kameda,
P. Levy,∗2 S. Mitsuoka,∗4 N. Miyahara,∗1 H. Miyatake,∗3 Y. Nakaya,∗1 D. Nagae,∗5 K. Ninomiya,∗1 M. Nitta,∗1
N. Ogawa,∗1 J. Onishi,∗1 M. Pearson,∗2 E. Seitaibashi,∗1 T. Toyoda,∗1 K. Tsukada,∗1 Y.X. Watanabe,∗3 andJ. Murata∗1

where J� is the nuclear polarization, and E, �p, and�σ are the energy, momentum and spin of the electron, respectively. The R-correlation term represents
a transversely polarized electron emitted from polarized nuclei that violates time reversal as well as parity
conservation. The transverse polarization of electron
is measured by Mott scattering. The up-down asymmetry of electrons scattered from a thin metal foil isdetermined using the incident and scattered tracks. In
the present study, a drift chamber has been used in
the Mott polarimeter for the ﬁrst time in order to nullify the major background and systematic eﬀects. The
drift chamber is located between a 8 Li beam stopper
and the metal foil in order to measure the backward
scattered tracks; the maximum ﬁgure of merit of thepolarimeter is expected at this location.
A physics experiment RNB08K04 was performed at
KEK-TRIAC in September 2008 using an 8% vertically polarized 8 Li beam at 178 keV/u and 105 pps3) .
Fig. 1 shows the Mott-scattering angular distribution obtained by electron-tracking analysis. The Rparameter is determined using the eﬀective analyzing
power in the Mott scattering as follows:
R = −0.020 ± 0.41(stat) ± 0.024(syst) (1σ).
We conﬁrmed that our detector setup worked well.
In order to achieve a higher precision, we had proposed that the next set of experiments be conducted
at TRIUMF-ISAC by using an 80% polarized 8 Li beamwith very high intensity, which could help us to measure the R-parameter with a precision of 0.01%. The
proposal was accepted, and the experiment number is
∗1
∗2
∗3
∗4
∗5

Counts

3

x10

30

γ

20

8

10

Li

θ
beta ray0
Decay angle γ (deg.)

A new experimental project, MTV (Mott polarimetry for T-Violation), that aims to test the time-reversal
symmetry in nuclear β-decay with high precision has
been launched at TRIUMF. Our aim is to measure the
R-parameter (deﬁned below) with a precision of 0.01%;
currently, at PSI, it is being measured with a precisionof 0.2%1) . The leptoquark model predicts a signiﬁcant T-violating eﬀect around 0.01% level when the
leptoquark mass is about 1 TeV1) . The R-parameteris deﬁned in the β-decay rate function as2)
�
� ��
�J�
p × �σ�J�� p�· +R····,
W ∝1+A
J E
J
E

160
120
80
40
0

100 140 180 220 260 0
Scattering angle θ (deg.)

10

3
20
30
x10
CountsFig. 1. Two-dimensional histogram for the decay angle γ
and the scattering angle θ of the Mott-scattering events.

S1183.
We performed the ﬁrst commissioning run at TRIUMF in November 2009. The entire experimental
equipment was shipped from KEK-TRIAC to TRIUMF in July 2009. In the test run, some technical problems were encountered in studies on beamintensity dependence of the event trigger rate. Two
major problems pertained to the space-charge eﬀect
and DAQ bandwidth. The space-charge eﬀect observed in the gas is not negligible in a 107 -pps beam
environment. We have started R&D for obtaining an
optimum chamber gas; we have taken isobuthane andCF4 into consideration instead of P10, which is being
used currently. The current DAQ is not capable of acquiring data for all the triggered events at the highest
intensity. Therefore, DAQ is being modiﬁed to utilize
the buﬀering mode instead of the event-by-event mode,
which is being used currently.
A physics run is scheduled for November 2010 withthe aim of reaching a precision of at least 0.1% precision, which is the value for the ﬁnal-state interaction
predicted by the standard model. We are also evaluating how to distinguish between the standard-modeleﬀects and the new physics signals, which are expected
to have nonzero values, using electron-momentum dependence. Precise measurement of the R-correlation
using a high-pitch cylindrical drift chamber will be
performed subsequently; the drift chamber is currently
under construction.
References

Rikkyo University
TRIUMF
KEK
JAEA
University of Tsukuba

1) R. Huber et al.: Phys. Rev. Lett. 90, 202301 (2003).
2) J.D. Jackson et al.: Nucl. Phys. 4, 206 (1957).
3) H. Kawamura: Ph. D. Thesis, Rikkyo University, Tokyo(2010).

- 27 -

1

RIKEN Accel. Prog. Rep. 43 (2010)

New neutron-deﬁcient actinide isotopes of 234 Bk and 230 Am
D. Kaji, H. Haba, Y. Kasamatsu, Y. Kudou, K. Morimoto, K. Ozeki, T. Sumita,∗1 A. Yoneda, H. Koura,∗2 N.
Sato,∗2 S. Goto,∗3 H. Murayama,∗4 F. Tokanai,∗5 K. Mayama,∗5 S. Namai,∗5 M. Takeyama,∗5 and K. Morita[234]
Bk, 230 Am, new isotope, GARIS

∗1
∗2
∗3
∗4
∗5

Faculty of Science and Technology, Tokyo University of Science
Advanced Science Research Center, Japan Atomic Energy
AgencyCenter for Instrumental Analysis, Niigata University
Faculty of Science,Niigata University
Department of Physics, Faculty of Science, Yamagata University- 28 -

a stainless steel wheel of diameter 420 mm. After theaerosol collection, the wheel was moved in steps at 30s intervals to position the foils between seven pairs of
Si PIN photodiodes (Hamamatsu S3204-09).The products was identiﬁed basis of the genetic correlations ofmother and daughter nuclei.
Total of 119 decay chains were assigned to subsequent decays from 234 Bk. The α(mother)-α(daughter)correlation plot is shown in Fig. 1. The 234 Bk had
the following decay modes: alpha decay, spontaneousﬁssion, and electron capture. The 234 Bk was connected to 230 Pu through two routes : [1] 234 Bk(α) →230
Am(EC) → 230 Pu and [2] 234 Bk(EC) → 234 Cm(α)→ 230 Pu. Then, 230 Pu underwent subsequent decaysof 230 Pu → 226 U → 222 Th → 218 Ra → 214 Rn.
Three groups of α-decay energies for 234 Bk wereidentiﬁed. The mean α-decay energies for the threegroups were 7.95, 7.87, and 7.75 MeV. The half-lifeof 234 Bk was determined to be 10 s. No α decay due
to 230 Am was detected in measurements that followed
the alpha decay of 234 Bk, but four SF events of 230 Am
were observed. The half-life of 230 Am was determined
to be 31 s. The decay properties of 234 Cm agree wellwith those indicated by reference values1) . Detailed
analysis is in progress.
References

7982 keV

8389 keV

9037 keV

Th-222

Ra-218Rn-2147050 keV

7420 keV
U-226
7570 keV
Th-222(2+) 7600 keV

U-226(2+)

Pu-230Cm-234107239 keV

1) P. Cagada et al.: GSI Sci. Rep. 2001, 15 (2002).

E(Daughter) [MeV]

99037 keV

Rn-214

8389 keV

Ra-21887982 keV

Th-222(2+)
U-226
U-226(2+)

7600 keV
7570 keV
7420 keV

Cm-234

7

Pu-2307750 keV
7870 keV

6

Th-2226

77239 keV
7050 keV

7950 keV

Two neutron-deﬁcient actinide isotopes, 234 Bk andits decay product 230 Am, were newly identiﬁed via a
197
Au(40 Ar,3n) reaction using the gas-ﬁlled recoil ion
separator (GARIS).
The decay properties of neutron-deﬁcient actinides
provide information on the nuclear mass surface close
to the proton drip line, nuclear structure of large deformed heavy nuclei, and ﬁssion properties far from
nuclear stability line via the electron-capture (EC) delayed ﬁssion. In this region, the detailed information
is not available because of their low production rates
and decay properties, such as EC-decay or spontaneousﬁssion.
Projectiles of 40 Ar with the charge state 11+ wereextracted from the 18-GHz ECR ion source and accelerated by RILAC (RIKEN Linear Accelerator). An
40
Ar beam with an energy of 189.5 MeV was extracted
from RILAC. The absolute accuracy in the beam energy was ±0.3 MeV. The typical beam intensities at thetarget were 1.5 × 1013 s−1 (corresponding to 2.5 pµA).
The target was prepared by the vacuum evaporationof metallic 197 Au on a 30-µg/cm2 carbon backing foil.
The target thicknesses were 513 µg/cm2 . Sixteen targets were mounted on a φ30 cm wheel, which rotated at
3000 rpm, so that they could withstand the irradiation
by high-intensity beams. The reaction products of interest were separated in ﬂight from the beams and the
majority of the nuclear transfer products by GARIS,
and were guided into a gas-jet chamber (i.d.: 100 mm;
depth: 20 mm) through a 0.7 µm-thick Mylar window,
which was supported by a circular-hole grid with 84%
transparency. The separator was ﬁlled with heliumgas at a pressure of 67 Pa. The magnetic rigidity for234
Bk measurement was set to Bρ = 1.92 Tm. In thegas-jet chamber, the reaction products were stopped
in He gas, attached to KCl aerosols, and continuouslytransported through a Teﬂon capillary (i.d.: 2.0 mm;
length: 10 m) to a rotating wheel system, MANON,in order to perform α-spectrometry. The He ﬂow rate
was 2.0 L min−1 , and the pressure inside the chamber
was 46 kPa. In MANON, the aerosols were depositedon 0.5 µm-thick Mylar foils placed at the periphery of

8

9E(Mother) [MeV]10

Fig. 1. A lot of α(mother)-α(daughter) correlation for subsequent decays from 234 Bk (see text).

RIKEN Accel. Prog. Rep. 43 (2010)

First Quantitative Study of Resonance Scattering of α-particles
Using a 21 Na Radioisotope Beam†
D. N. Binh,∗1 L. H. Khiem,∗2 N. T. Tho,∗2 H. Yamaguchi,∗1 Y. Wakabayashi,∗1 S. Hayakawa,∗1
T. Hashimoto,∗1 T. Teranishi,∗3 N. Iwasa,∗4 N. Kume,∗4 N. Kato,∗5 and S. Kubono∗1[RI beam, Novae, X-ray burst]

∗1
∗2
∗3
∗4
∗5

Center for Nuclear Study, Graduate School of Science, University of Tokyo
Institute of Physics, Vietnamese Academy of Science andTechnology
Department of Physics, Kyushu University
Department of Physics, Tohoku University
Department of Physics, Yamagata University- 29 -

by the ∆E-E method. The alpha scattering data wereanalyzed to obtain the excitation function. Five resonances were observed, as shown in Fig. 1. The gap ataround Ecm = 3.5 MeV in the ﬁgure is due to the deadlayer of the MDSSD. A combination of spins and parDifferential Cross Section [b/sr]

Nucleosynthesis of 22 Na is an interesting subject because of possible γ-ray observation and the presenceof isotopic anomalies in the presolar grains1,2) . 22 Nashould be mainly produced in the NeNa cycle. It is along-lived radioisotope with a half-life of 2.6 years; its
β-decay leads to the ﬁrst excited state which promptly
followed by the emission of an 1.275 MeV γ-ray3) . This
γ-ray is a candidate to detect by satellite observatories
to understand stellar events. At high temperatures,the 21 Na(α,p)24 Mg reaction could play a signiﬁcantrole in the NeNa cycle progressing to the MgAl cycle
and beyond. Clearly, the 21 Na(α,p)24 Mg stellar reaction would make a branching reaction on 21 Na and bypass 22 Na, resulting in a reduction in 22 Na production.
Therefore, it could be directly related to the 1.275 MeV
galactic γ-ray observation and the Ne-E problem4) . It
could be also important in understanding the earlystage of the rp-process5) . Resonances observed by theresonance scattering of α-particles on 21 Na and theirresonant parameters are very important for calculating
the stellar reaction rate of the 21 Na(α,p)24 Mg reaction.
Measurement of the resonance scattering of αparticles using a low energy 21 Na radioisotope (RI)
beam in inverse kinematics was performed for the ﬁrst
time by the thick target method. The beam wasproduced at the CNS Radio Isotope Beam separator (CRIB) of the University of Tokyo6) . The 21 Na
particles were produced by the (d,n) reaction in inverse kinematics; a 20 Ne primary beam accelerated
up to 6.2 MeV/u by the RIKEN-AFV cyclotron wasused. The 21 Na beam was selected and puriﬁed by
the CRIB facility, and ﬁnally, at the scattering chamber containing the experimental setup, we obtained
a 39.5-MeV beam with of about 93% purity. Energies and positions of both proton and α-particles were
measured in the α + 21 Na scattering by three ∆E-E
telescopes mounted at three diﬀerent angles (6 ◦ , 16 ◦ ,and 26 ◦ ) with respect to the beam line. Each telescope consisted of a Micron double-sided silicon detector (MDSSD), a Hamamatsu position sensitive silicondetector (HPSSD), and two solid state silicon detectors(SSD). Protons and α-particles were clearly identiﬁed

0.35

Measured data
Fitting

0.3

Angle: 0 - 5 degree

0.25
0.2

5/2

0.15
0.1
0.05

+
7/2

+
5/2

+
5/2

+
3/2

0
1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5

Energy in Center of Mass [MeV]Fig. 1. Excitation function of resonance scattering of αparticles on 21 Na.

ities has been deduced successfully so far by applying
the R-matrix method. The best ﬁt of this combination is shown in Fig. 1, and the result of the R-matrix
analysis is presented in Table 1.
Table 1. R-matrix analysis result
Er (MeV)3.390 ± 0.305
3.983 ± 0.279
4.516 ± 0.135
5.214 ± 0.260
5.760 ± 0.058

Γ (MeV)
0.523 ± 0.052
0.217 ± 0.017
0.231 ± 0.009
0.371 ± 0.022
0.233 ± 0.005

Jπ
5/2−
7/2+
5/2+
5/2+
3/2+


3
2
2
2
2

The analysis is still in progress. We are investigating other possible combinations of spins and parities
for which the R-matrix ﬁt gives reasonable χ2 values(within the standard deviation).
References
1) P. Jean et al.: “Search for a Galactic 1275 KeVLine Emission with SPI/INTEGRAL”, Proc. 5th INTEGRAL Workshop, Munich, Germany, 2004.
2) M. Aliotta: Eur. Phys. J. Special Topics 150, 201(2007).
3) D. D. Clayton and F. Hoyle, Astro. J. 101, 187 (1974).
4) M. Arnould and H. Norgaard: Astro. Astrophys. 64,
195 (1978).
5) S. Kubono: Nucl. Phys A 558, 305 (1995).
6) S. Kubono et al.: Eur. Phys. J. A 13, 217 (2002).

RIKEN Accel. Prog. Rep. 43 (2010)

Progress in 30 S Beam Development for a Measurment of 4 He(30 S,p)D. Kahl,∗1 A. A. Chen,∗2 S. Kubono,∗1 D. N. Binh,∗1 J. Chen,∗2 T. Hashimoto,∗1 S. Hayakawa,∗1 D. Kaji,∗4 A.
Kim,∗4 Y. Kurihara,∗1 N. H. Lee,∗4 S. Michimasa,∗1 S. Nishimura,∗4 Y. Ohshiro,∗1 K. Setoodeh nia,∗2 Y.
Wakabayashi,∗1,∗5 and H. Yamaguchi,∗1[Unstable nuclei, astrophysics]

We produce 30 S via the 3 He(28 Si,30 S)n reaction bybombarding a cryogenic gas target8,9) of 3 He at 90 K
with beams of 28 Si. By placing a 2.5 µm Be foil after
the production target, we are able to increase the population of the 30 S16+ species (compared to the chargestate distribution of the gas-cell Havar exit window),
which is easier to purify from beam contaminates. Although the 30 S14+ species is more preferentially populated at the achromatic focal plane F2, as shown in
Fig. 1, it is diﬃcult to separate and purify. The beam
purity at the target focal plane F3 is improved compared to Fig. 1 by passing the beam through a Wien
(velocity) ﬁlter after F2.
We successfully developed a 30 S16+ RI beam of 104
pps of 25% purity and Ebeam = 30 ± 3 MeV on target
normalized to a 7.4 MeV/u 28 Si9+ primary beam at
1.3 eµA; the primary beam intensity is limited by the
maximum heat deposit of 2 W in the 2.5 µm Havar
exit window of the production target. The improvement compared to our previous work can mainly be
attributed to recent upgrades to the practical K valueof the Nishina Center AVF cyclotron. Consistent withpredictions from the ion-optic modeling program MOCADI, our transmission eﬃciency is primarily limited
by energy straggling in the production target, and
∗1
∗2
∗3
∗4
∗5

Center for Nuclear Study, University of Tokyo
Department of Physics & Astronomy, McMaster University,
CanadaRIKEN (the Institute of Physical and Chemical Research)
Department of Physics, Ewha Womans University, Korea
Advanced Science Research Center, Japan Atomic Energy
Agency (JAEA), Japan- 30 -

100
90
80
F2 SSD Energy (MeV)

We performed a third and ﬁnal low-energy 30 S RI
beam development test in preparation for a future
measurement of the 4 He(30 S,p) cross section. Our
July 2009 experiment, reported here, was a follow-up
to our previous beam tests in December 20061) andMay 20082) . This work is performed at the low-energy
Center for Nuclear Study (CNS) radioactive ion beam
(CRIB) separator facility3,4) of the University of Tokyoand located at the Nishina Center of RIKEN. In 2010,
we will perform the ﬁrst-ever direct measurement of
the 4 He(30 S,p) cross-section at astrophysical energies
relevant to Type I X-Ray Bursts. The 30 S(α,p) reaction rate is important to the overall energy generationof X-Ray Bursts5) , inﬂuences the neutron star crustal
composition6) , and may explain the bolometric doublepeaked nature of some rare X-Ray Bursts7) .

30 15+

70
60

30 14+

50

28

P
Si13+
30 14+
S

40
30

P
28 14+
Si
30 15+
S

30 16+

S

20
10
0

10

20
30
40
50
60
F0 to F2 Time of Flight (ns, arbitrary offset)

7080

Fig. 1. ToF-E spectrum using a delay-line PPAC and SSD
at F2. 30 S16+ is clearly separated.

thus the ability to accelerate a 28 Si9+ beam up to 7.4
MeV/u is a considerable improvement for 30 S beams
at CRIB. If we normalize our previous results to thehigher primary beam current used in this work, use of
the Be foil only increased the production of 30 S16+ by
a factor of two, where as we expected this increase to
be a factor of ten from previous work with carbon foils
and the predictions of LISE++; this discrepancy canbe somewhat accounted for by the fact that the Be foil
was partially broken.
In September 2010, we will measure the 4 He(30 S,p)cross section on an event-by-event basis using an active target method using the thick-target method ininverse-kinematics10) . It is critical that we may get
a 28 Si9+ beam at 1.3 eµA with long-term currentstability delivered to the primary beam focal point of
CRIB for the future experiment using the 30 S beamdeveloped and detailed in this report.
References
1) D. Kahl et al.: ASPC 393 (2008) 219.
2) D. Kahl et al.: PoS NIC X (2008) 171.
3) S. Kubono et al.: Eur. Phys. J. A 13 (2002) 217.
4) Y. Yanagisawa et al.: Nucl. Instr. Meth. A539 (2005) 74.
5) A. Parikh et al.: ApJS 178 (2008) 110.
6) H. Schatz and K. E. Rehm:
Nucl. Instr. Meth.
A777 (2006) 601.
7) J. L. Fisker, F.-K. Thielemann and M. Wiescher: ApJ
608 (2004) L61.
8) H. Yamaguchi et al.: Nucl. Instr. Meth. A589 (2008) 150.
9) G. Amadio et al.: Nucl. Instr. Meth. A590 (2008) 191.
10) K. P. Artemov et al.: Soviet J. Nucl. Phys. 52 (1990) 408.

RIKEN Accel. Prog. Rep. 43 (2010)

New measurement of resonance scattering of alpha particles on 7 Li
H. Yamaguchi,∗1 T. Hashimoto,∗1 D.N. Binh,∗1 D. Kahl,∗1 S. Hayakawa,∗1 Y. Wakabayashi,∗2 T. Kawabata,∗3
and T. Teranishi∗4[Nuclear astrophysics, Nuclear cluster structure, unstable nuclei]

∗1
∗2
∗3
∗4

Center for Nuclear Study, Graduate School of Science, University of Tokyo
Advanced Science Research Center, JAEA
Department of Physics, Kyoto University
Department of Physics, Kyushu University- 31 -

small number of protons and tritons, which are possibly from 7 Li(α,p) reaction and from the break up of
7
Li, were observed in the measurement.
The obtained energy spectrum of α particles isshown in Fig. 1. The spectrum had peaks consistent
with those observed in previous measurements10,11) .
A low-background measurement was successfully performed, and it was demonstrated that the thick-target
inverse-kinematics method can be adopted for measurements involving light beams and target particles
with the minimum atomic number difference (∆Z =1). The calculation of the kinematics by taking into
account the energy loss in the gas target can provide
the excitation energy of 11 Bfrom the measured energyof the alpha particle. Thus, the excitation fuction forthe 7 Li+α elastic scattering will be obtained.
References
1) Y. Kanada-En’yo: Phys. Rev. C 75, 024302 (2007).
2) A. Tohsaki et al.: Phys. Rev. Lett. 87, 192501 (2001).
3) T. Kawabata et al.: Phys. Rev. C 70, 034318 (2004).
4) T. Kawabata et al.: Phys. Lett. B 646, 6 (2007).
5) S. Kubono et al.: Eur. Phys. J. A 13, 217 (2002).
6) Y. Yanagisawa et al.: Nucl. Instrum. Methods Phys.
Res., Sect. A 539, 74 (2005).
7) K. Artemov et al.: Sov. J. Nucl. Phys. 52, 408 (1990).
8) H. Yamaguchi et al.: Phys. Lett. B 672, 230–234 (2009).
9) F.Ajzenberg-Selove, Nucl. Phys. A 506, 1 (1990).
10) R.Y. Cusson et al.: Nucl. Phys. 86, 481–508 (1966).
11) N. Soić et al.: Nucl. Phys. A 742, 271–290 (2004).

3500

Li+α elastic scattering
on-line (preliminary) analysis

7

3000

Counts (arb. units)

In recent years, the exotic cluster structures in 11 B
and 11 C nuclei have attracted considerable attention
1)
11
B at the excitation energy. The 3/2−
3 state of
Eex =8.11 MeV is considered to be a dilute cluster state2), in which two alpha particles and 3 He are weakly interacting. In particular, the α-cluster structure in 11 B
was studied by measuring its isoscalar monopole andquadrupole strengths in the 11 B(d, d ) reaction. The
studies indicated that the mirror state of the 8.11MeV state has a dilute cluster structure.3,4) . In thepresent study, we used 7 Li+α resonant elastic scattering to investigate the cluster structures. The strengthsof the resonances are expected to provide information
about the α-cluster structure. The 7 Li+α system isalso related to the astrophysical reaction 7 Li(α,γ)11 B.
The study of resonance parameters carried out in thepresent work should contribute to the precise determination of the 7 Li(α,γ)11 B reaction rate at high temperatures (T9 > 1).
The measurement of the 7 Li+α elastic scattering
was performed at CRIB5,6) using the thick-target ininverse-kinematics method7,8) to determine the excitation function when the excitation energy of 11 B is
10–13 MeV. The excited states of 11 B in this energy
region have been studied by 7 Li+α elastic scatteringand other methods9) ; however, some of the resonanceparameters are still unclear. In particular, the alphawidths were not accurately determined. Using inverse
kinematics, the excitation function at 180 deg in thecenter-of-mass system, where potential scattering is
minimum and the resonances can be observed mostclearly, was measured for the first time.
The 7 Li beam was accelerated in the AVF cyclotron
and transported to the final focal plane (F3) of CRIB.
The beam had an energy of 13.7 MeV, and was collimated by a 3 × 3-mm aperture at F3. A helium-gas
target consisting of a 50-mm-diameter duct and a smallchamber was used in the measurement. α particles recoiling at forward angles were detected and identified
by the “∆E-E counter”. The counter consisting of
20-µm- and 480-µm-thick silicon detectors was placedin the small chamber. Measurements for 2.9 × 1010
particles of 7 Li injected into a helium-gas target were
performed for 2.5 days. Most of the particles measured
was α particles from the elastic scattering, and only a

2500
2000
1500
1000
500
0
0

1

2

3

4

5

6

7

8

Measured energy of α particle (MeV)

Fig. 1. Energy spectrum of the α paticles in the measurement. The α particles are mostly from 7 Li+p elastic
scattering.

2.

Nuclear Physics (Theory)

RIKEN Accel. Prog. Rep. 43 (2010)

Subsystem correlations in Coulomb breakup reaction of 6 He
Y. Kikuchi,∗1 T. Myo,∗2,∗4 M. Takashina,∗3,∗4 K. Katō,∗1 and K. Ikeda[NUCLEAR REACTIONS: Halo nuclei, Coulomb breakup]

∗1
∗2
∗3
∗4

Division of Physics, Graduate School of Science, Hokkaido
University
General Education, Faculty of Engineering, Osaka Instituteof Technology
Department of Medical Physics and Engineering, Graduate
School of Medicine, Osaka University
Research Center for Nuclear Physics (RCNP), Osaka University- 33 -

dσ/dEα-n [arb. units]

8

Calc.
Direct
Exp.

(a)

6
4
2
0

0

8
dσ/dEn-n [arb. units]

The purpose of our study is to understand the structures of two-neutron halo nuclei such as 6 He and 11 Li
via the Coulomb breakup reactions. Here, we focus
on the correlations of the binary subsystems of coren and n-n in two-neutron halo nuclei. We clarify the
relationship between E1 excitations and the correlations in halo nuclei. In this study, we investigate thebreakup of 6 He into α + n + n three-body continuum
states.
To describe the subsystem correlations in threebody breakups, we use complex-scaled solutions of the
Lippmann-Schwinger equation (CSLS)1) . In the CSLS,
the formal solution of the Lippmann-Schwinger equation is combined with the complex scaling method.
CSLS makes it possible to evaluate the physical quantities as functions of the relative energies of subsystems.
As a result of this advantage, we can directly discuss
the subsystem correlations if the breakup observables
are known. We calculate the invariant mass spectraof the Coulomb breakup cross section of 6 He for bothsubsystems of α-n and n-n.
Figure 1 shows the calculated invariant mass spectra and the one obtained from the experiments2) . The
results obtained using the CSLS for the α-n and n-n
subsystems reproduce the observed spectra well. In
Fig. 1(a), it is found that the spectrum has a peakat around Eα-n ∼ 0.7 MeV, which corresponds to5
He(3/2− ) resonance energy. This result indicates theimportance of the sequential decay via the 5 He(3/2− )resonance in the Coulomb breakup reaction of 6 He.
In the invariant mass spectrum shown in Fig. 1(b), a
higher number of the cross section is seen near zeroenergy region. This behavior can be understood as theeﬀect of the n-n virtual state in the ﬁnal states.
To estimate the ground-state correlation in the invariant mass spectra, we also show the results for the
breakup components obtained for the transition fromthe ground state to the non-interacting continuum
states. This components correspond to the Fouriertransformation of the ground state and are shown asdashed lines in Fig. 1. In both panels, we can see thatthe spectra for the direct breakup have no clear peaks.
By comparing the orignal and direct breakup results,
we conclude that it is diﬀcult to obtain the informa-

0.5
1
1.5
2
5
He(3/2 ) Eα-n [MeV]

3

2.5

3

Calc.
Direct
Exp.

(b)

6

2.5

4
2
0

0

0.5

1

1.5
2
En-n [MeV]Fig. 1. Invariant mass spectra given in arbitrary units. The
panels (a) and (b) show results with respect to the αn and n-n subsystem energies, respectively. The solidlines represent the original results obtained using CSLS,
in which all the ﬁnal-state interactions are taken into
account, and the dashed lines represent the results forthe direct breakup components obtained for the transition from the ground state to the non-interacting threebody continuum states. The open squares with error
bars denote experimental data2) . The arrow in panel(a) indicates the resonance energy of 5 He(3/2− ).

tion on the ground-state correlation directly from the
Coulomb breakup. This fact indicates the strong inﬂuence of the ﬁnal state interactions on the breakup
cross section.
References
1) Y. Kikuchi, T. Myo, M. Takashina, K. Katō, andK. Ikeda: Prog. Theor. Phys. 122, 499 (2009),
Y. Kikuchi, K. Katō, T. Myo, M. Takashina, andK. Ikeda: Phys. Rev. C 81, 044308 (2010).
2) T. Aumann et al.: Phys. Rev. C 59, 1252 (1999).

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

One-neutron removal strength of 7 He into 6 He using the complex
scaling method
T. Myo,� 1� 2 R. Ando,� 3 and K. Katō,� 3[Nuclear structure, Unstable nuclei, Cluster model, Resonance]

†
� 1
� 2
� 3

Condensed from the article in Phys. Rev. C80, 014315(2009)
General Education, Faculty of Engineering, Osaka Instituteof Technology
Research Center for Nuclear Physics, Osaka University
Graduate School of Science, Hokkaido University- 34 -

Table 1. Energies and widths of the 7 He resonances measured from 4 He+3n threshold in MeV, and the corresponding S factors of the 6 He-n components.

S(E)

3/2�1
3/2�2
3/2�3
1/2�
5/2�

S(E)

In recent times, many experiments on the unboundnucleus 7 He, have been reported1) . However, there
are still contradictions in the observed energy levels,in particular, in the excited states. Experiments suggest that the excited states of 7 He appear as four-bodyresonances above 4 He+n+n+n threshold energy.
Theoretically, when we discuss the structures of 7 He,
it is important to consider its many-body decays to thechannels 6 He+n, 5 He+2n, and 4 He+3n. The purposeof this study is to investigate the resonance structuresof 7 He by imposing the accurate boundary conditionsof many-body decays. We employed the cluster-orbitalshell model of the 4 He+n+n+n system, in which theopen channel eﬀ ects of the multineutron emissions
are explicitly taken into account. We will describe
the many-body resonances under the correct boundary conditions using the complex scaling method. We
employed the Hamiltonian to obtain the 4 He-n scattering data and the 6 He energies2) .
We obtained ﬁ ve resonances of 7 He as shown in Table 1. Further, we investigated the spectroscopic factors (S factors) of the 6 He-n component, which are important to understand the coupling between 6 He andthe additional neutron in 7 He. It was found that the
6
7
He(2+
1 ) state contributed largely in several He states.
�
6
Only in the case of the 1/2 state, the He(0+1 ) component was dominant and close to unity. This result
indicates that the 1/2� resonance can be considered
to be a single particle resonance of the p1/2 neutron
surrounding the halo state of 6 He.
In Fig. 1, we show the one-neutron removal strength
S(E) from the 7 He ground state into 6 He; this strengthis determined by taking into account the three-bodycontinuum components of 6 He in the ﬁ nal states aswell as the 2+
1 resonance shown in Table 1. From
Fig. 1 (a), it is found that the contribution of 6 He(2+ )is considerably large, resulting in the peak value atthe resonance energy of 2+
The 6 He(0+1.
1 ) contribution of 0.61 agrees with the recent observation of
0.64 ± 0.093) . The strengths of other spin states madesmall contributions, as shown in Fig. 1 (b). The
peak values for these states was observed at approximately 1 MeV. This structure is a threshold eﬀ ectof the 5 He(3/2� )+n two-body decay, which starts at

Energy−0.790
2.58
4.53
0.26
2.46

10
9
8
7
6
5
4
3
2
1
0

Width
0.014
1.95
5.77
2.19
1.50

He(0+
1 )-n
0.64 + i0.06
0.005 + i0.01
0.003 + i0.0002
1.00 − i0.13
0.00 + i0.00

6

6

He(01)

-1

0

0.14
0.12
0.10
0.08
0.06
0.04
0.02
0.00

6

(a)

+

He(2 )+

12
3+
21 E [MeV]
6

2

5

(b)

He(1+)
6

1

4

He(3+)
6

0

He(2+
1 )-n
1.55 − i0.31
0.95 + i0.02
0.02 − i0.004
0.10 − i0.05
0.95 + i0.02

6

He(0+)
3

4

5

E [MeV]
Fig. 1. One-neutron removal strength of 7 He to 6 He(J π ,E)states measured from the 4 He+n+n threshold energy.
The vertical arrow in (a) indicates the resonance energyof 6 He(2+1 ).

0.74 MeV. From these results, it is concluded that thecontribution of the 6 He(2+1 ) is maximum in the oneneutron removal strength of 7 He above the 4 He+n+n
threshold energy.
References
1) F. Skaza et al.: Phys. Rev. C73, 044301 (2006), andreferences therein.
2) T. Myo, K. Kat�o, K. Ikeda: Phys. Rev. C76, 054309(2007).
3) F. Beck et al.: Phys. Lett. B645, 128 (2007).

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Five-body resonances of 8 He using the complex scaling method
T. Myo,� 1� 2 R. Ando,� 3 and K. Katō,� 3[Nuclear structure, Unstable nuclei, Cluster model, Resonance]

� 1
� 2
� 3

General Education, Faculty of Engineering, Osaka Instituteof Technology
Research Center for Nuclear Physics, Osaka University
Graduate School of Science, Hokkaido University- 35 -

Table 1. Matter (Rm ) and charge (Rch ) radii of 6,8 He compared with the experiments; a4) , b5) , c6) , d3) .

Rm
He
Rch
Rm
8
He
Rch
6

Present [fm]
2.37
2.01
2.51
1.92

Experiments [fm]2.33(4)a 2.30(7)b 2.37(5)c
2.068(11)d2.49(4)a 2.45(7)b 2.49(4)c1.929(26)d6

E − E(4He) [MeV]Recently, many experiments on 8 He have been reported. Most of the excited states of 8 He are locatedabove the 4 He+4n threshold energy1) . This indicatesthat the observed resonances of 8 He can decay into thechannels of 7 He+n, 6 He+2n, 5 He+3n, and 4 He+4n.
This multiparticle decay of 8 He makes it diﬃcult toobserve its excited states.
The purpose of this study is to carry out the resonance spectroscopy of 8 He by imposing the accurateboundary conditions of many-body decays. We employ the cluster-orbital shell model of the ﬁ ve-body
4
He+n+n+n+n system, in which the open channel
eﬀ ects of the multineutron emissions are taken into
account explicitly. We describe the many-body resonances under the correct boundary conditions by using
the complex scaling method (CSM). It is a challenge
to describe the ﬁ ve-body nuclear resonances by using
CSM. We employ the Hamiltonian, which reproduces
the 4 He-n scattering data and the 6 He energies2) .
Figure 1 shows the obtained energy spectra of He
isotopes. We can observe a good agreement between
theory and experiment. The matter and charge radiiof 6 He and 8 He nicely reproduce the experiments, as
listed in Table 1. We also successfully predict 0+
2 of
8
He as a ﬁ ve-body resonance in CSM; the excitationenergy and decay width of this resonance are 6.21 MeV
with 3.19 MeV, respectively.
We calculate the pair number of four valence neutrons in 8 He; the pair number∑ is deﬁ ned by the matrix element of the operator � ≤β A†J π (� β)AJ π (� β).
Here, � and β represent the single-particle orbits ofneutrons, and A†J π (AJ π ) is the creation (annihilation) operator of a neutron pair with spin-parity J π .
This quantity helps us to understand the pair coupling
structures of four neutrons. Figure. 2 shows the pair++numbers for 8 He (0+neu1,2 ). In the 01 state, the 2+tron pair is close to ﬁ ve and the 0 pair is almost
unity. This result was obtained from a main conﬁ guration of (p3/2 )4 with the probability of 86% using
the CFP decomposition ( 1 and 5 for 0+ and 2+ , re+spectively). The 0+
2 state has almost two 0 neutron
pairs in addition to the 2+ pairs. This is consistent
with the (p3/2 )2 (p1/2 )2 conﬁ guration with a probability of 96%; this conﬁ guration is decomposed into thepairs of 0+ , 1+ and 2+ with occupations of 2, 1.5, and2.5, respectively. In summary, by using CSM, we havesuccessfully obtained the 0+
2 state as a ﬁ ve-body reso-6
Γ=8.76 0+4
205.88 +

Γ=5.84

1/2

−

0.59

3/2

−

1
+
3.78 2

4

5

He

1.74 5/2

2

E( He)

He

Γ=3.19 +0−2.35 1/2−

0.051 3/2

0+

6

3/2

-

1.91 3/2−

0.132 +

−2−4

Γ=5.90

7

He

4
2
0

−

0+

8

+

He(0 )−2−4

Fig. 1. Energy levels of He isotopes. Small numbers aredecay widths. Black and gray lines represent theory
and experiments, respectively.

5
4
3
2
1
0

+

01

8
0+2

He

0+ 0- 1+ 1- 2+ 2- 3+ 3π
J (2n)

8
Fig. 2. Pair numbers of the 0+
1,2 states of He.

nance, which has two 0+ pairs of neutrons.
References
1) F. Skaza et al.: Nucl. Phys. A788, 260c (2007), andreferences therein.
2) T. Myo, R. Ando and K. Kat�o: Phys. Rev. C80, 014315(2009).
3) P. Mueller et al.: Phys. Rev. Lett. 99, 252501 (2007).
4) I. Tanihata et al.: Phys. Lett. B 289, 261 (1992).
5) G. D. Alkhazov et al.: Phys. Rev. Lett. 78, 2313 (1997).
6) O. A. Kiselev et al.: Eur. Phys. J. A25, Suppl. 1, 215(2005).

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Gamow-Teller transitions from 9,11 Li to 9,11 Be
Y. Kanada-En’yo∗1

B GT

8

2

0

8

0

4
2

8

0

15

20

25

30

5

10

15

20

25

30

5

15

15

10

20

25

30

20

25

30

5/23/21/2-(d) exp
11Be

6
4
2
0

10

(c) AMD
11Be

6

0

5

(b) exp
9 Be

B GT

12
10
8
6
4
2
0

B GT

5/23/21/2-(a) AMD
9 Be
4
6

0

B GT

Experimental studies of the β decays from unstable
nuclei near drip lines are currently progressing due torecent advances in experimental techniques. In recent
years, the β decays of 9 Li and 11 Li have been measured
in several experiments, e.g., at the ISOLDE facility in
CERN. They provide information on new states in 9 Be
and 11 Be such as their excitation energies, spins, andB(GT ) values. In the β decay of 9 Li, the GT transitions to the low-lying 9 Be states at Ex ≤ 10 MeV are
weak, while strong transitions have been reported to
the 11.81 MeV state1–3) which give an abnormal large
B(GT ) value as a few factor large as the theoreticalvalue calculated by a shell model4) . The β decay has
also been measured experimentally for the drip-line nucleus, 11 Li5–8) , and many excited states of 11 Be wereobserved in the low energy region.
In this paper, we investigate the GT transition
strengths of the β decays, 9 Li→9 Be and 11 Li→11 Be,
with a theoretical method of antisymmetrized molecular dynamics(AMD)9,10) . The distribution of theB(GT ) values is analyzed for each spin of ﬁnal states.
B(GT ) distribution for the decays 9 Li→9 Be and11
Li→11 Be is shown in Fig. 1. The calculated B(GT )values are small for transitions to low-lying states of
Be isotopes because of the 2α-core structures in theﬁnal states. Signiﬁcant strengths are found in theB(GT ) distribution to non-cluster states of 9 Be in the
Ex ≥ 10 MeV region. Also in 11 Li→11 Be decays, relatively large B(GT ) values are found for excited states
at excitation energy Ex ≥ 10 MeV.
Particular attention was paid to the strong βtransition from 9 Li to 9 Be(5/2− ) state at 11.8 MeV
which was reported experimentally1–3) . The present
results are inconsistent with the strong GT transition
to the 5/2− state which shows a large fraction of the
Ikeda sum rule value. Also in terms of the sum rule,the experimental value B(GT ) = 8.9 for the 5/2− state
seems too large to be described by theoretical calculations if the 9 Li ground state has an ordinary structure.
This work is the ﬁrst in which the AMD method wasapplied to the study of GT transitions to highly excitedstates. One advantage of the present method is that
one can describe various ﬁnal states in the daughter
nucleus(Be), such as low-lying cluster states and highlying non-cluster states. Although the present model
space is not a complete basis, it exhausts the GT transition strengths exactly.

0

5

10

Ex (MeV)Fig. 1. B(GT ) distribution for the decays 9 Li→9 Be and11
Li→11 Be. The B(GT ) values to 1/2− , 3/2− , and5/2− states of 9,11 Be are piled up. An arrow in eachpanel indicates the energy of the IAS state. The value(gA /gV )2 is taken to be 1.262 . The theoretical values are calculated by using the MV1 force and theG3RS spin-orbit force with parameters, b = h = 0.15,m = 0.62 and uI = −uII = 3000 MeV.
2) W. T. Chou, E. K. Warburton and B. A. Brown, Phys.
Rev. C 47, 163 (1993).
3) Y. Prezado et al., Phys. Lett. B576, 55 (2003).
4) D.J. Millener, Eur. Phys. J. A 25, s01, 97 (2005).
5) N. Aoi et al., Nucl. Phys. A616, 181c (1997).
6) H.O.U. Fynbo et al., Nucl. Phys. A736, 39 (2004).
7) Y. Hirayama et al., Phys. Lett. B611, 239 (2005).
8) M. Madurga et al., Phys. Lett. B 677, 255 (2009).
9) Y. Kanada-En’yo, H. Horiuchi and A. Ono, Phys. Rev.
C 52, 628 (1995); Y. Kanada-En’yo and H. Horiuchi,
Phys. Rev. C 52, 647 (1995).
10) Y. Kanada-En’yo and H. Horiuchi, Prog. Theor. Phys.
Suppl.142, 205 (2001).

References
1) G. Nyman et al. [ISOLDE Collaboration], Nucl. Phys.
A 510, 189 (1990).
∗1

Department of Physics, Kyoto University, Japan- 36 -

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Systematic study of adiabatic-energy surfaces of Be isotopes †M. Ito,∗1[Nuclear structure, cluster model, chemical bonding]

∗1

20

6

10

Energy ( MeV )In the last two decades, experiments performed using a secondary RI beam significantly improved our understanding of light neutron-rich nuclei. In particular,
substantial efforts have been devoted to the study ofthe molecular structure of Be isotopes. These isotopes
are typical examples of two-center superdeformed systems, which build on 8 Be with an α+α rotor. Like
the covalent electrons of molecules, low-lying states ofthese systems are characterized by the formation ofmolecular orbitals (MOs) such as π − and σ + orbitals1) .
Furthermore, recent experiments on 12 Be have revealed the existence of many resonant states withsmall energy spacings of less than 1 MeV2,3) . The observed resonances decay strongly into 6 Heg.s. +6 Heg.s.
and α+8 Heg.s. . Similar resonances, which decay into
He isotopes, have also been observed in 10 Be2) and14
Be3) . The observed resonances are the candidates
for the X He+Y He molecular resonances (X,Y = 4, 6,8) analog to atomic orbital (AO) configurations.
We have attempted to unify the studies on the nuclear structures of 10,12 Be and the nuclear reactionsof α+6,8 He4–6) by applying the generalized two-center
cluster model (GTCM). In this model, various AO
configurations with excess neutrons can be consideredaround the α+α cores, and the eigenvalue problem issolved using the basis functions of the constructed AO
configurations. We found that the characteristic structural change from MOs to AOs is as the function of
excitation energy, and many resonances with small energy intervals are reproduced well.
Recently, we have extended our studies to include
the neutron drip-line systems 14,16 Be = α+α+Xn (X= 6, 8) In this report, we present the adiabatic energy
surfaces (AESs) calculated using the GTCM and discuss the possible appearance of X He+Y He structuresin heavier Be isotopes. The adiabatic states can be determined by solving the eigenvalue problem for a fixed
α − α distance. The AESs are obtained by connecting
a series of adiabatic states, as shown by the two curves
in Fig. 1.
Two deep minima are observed in the lowest two
AESs of 14 Be. When the α−α distance becomes large,
the energies of the AESs increase, and AESs A and
B are smoothly connected to the asymptotic channels
8of 6 Heg.s. +8 Heg.s. and 6 He(2+1 )+ Heg.s. , respectively.
This means that the adiabatic states on the rising partof the energy curve (shown by the dotted lines with anarrow) have an enhanced component of the respective
asymptotic channels. Previous calculation of the en-

+

B

6

0

8

He + He

A

14

−10

8

He(21 ) + He

2

4

6
8
10
α − α Distance ( fm )Be
12Fig. 1. Adiabatic energy surfaces (AESs) of 14 Be. The circles and curves represent the adiabatic states and the
AESs, respectively. The origin of the energy axis istaken to be the threshold energy for 6 He+8 He.

ergy levels on the basis of the adiabatic states indicatethat the adiabatic states of 10,12 Be4–6) are stabilized as
the resonant states. Therefore, the present calculation
results strongly suggest the possible appearance of the
6
8
Heg.s. +8 Heg.s. and 6 He(2+1 )+ Heg.s. structures in the14
excited state of Be. We can expect 8 Heg.s. +8 Heg.s.
structures in 16 Be because there appears a connection
between the local minimum and the asymptotic channels in AES. We should calculate the energy spectra toinvestigate the possibility of the formation of 6 He+8 He
and 8 He+8 He. The calculation of energy level is now
under progress.
References
1) N. Itagaki and S. Okabe: Phys. Rev. C 61, 044306(2000).
2) M. Freer et al.: Phys. Rev. C 63, 034301 (2001).
3) A. Saito et al.: Suppl. Prog. Theor. Phys. 146, 615(2003).
4) M. Ito, K. Kato and K. Ikeda: Phys. Lett. B 588, 43(2004); I. Mod. Phys. Lett. A 18, 178 (2003).
5) Makoto Ito: Phys. Lett. B 636, 293 (2006); I. Mod.
Phys. Lett. A 21, 2429 (2006).
6) M. Ito, N. Itagaki, H. Sakurai, and K. Ikeda: Phys. Rev.
Lett. 100, 182502 (2008); M. Ito and N. Itagaki: Phys.
Rev. C 78, 011602(R) (2008).

Department of Pure and Applied Physics, Kansai University- 37 -

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Study of A = 7 isotiplet Λ hypernuclei with the four-body clustermodel†
E. Hiyama Y. Yamamoto,∗1 T. Motoba,∗2 and M. Kamimura∗3[hypernuclei, cluster model, hyperon-nucleon interaction]

†
∗1

∗2

∗3

Condensed from the article in Phys. Rev. C. 80,054321(2009)
Physics Section, Tsuru University
Laboratory of Physics, Osaka Electro-Communication University
Department of Physics, Kyushu University- 38 -

is predicted to be 5.36 MeV without taking the CSB
effect into account.
Next, let us consider tha CSB effect in A = 7
isotriplet hypernuclei. In the case of 7Λ Li, the calculated BΛ is 5.29 MeV, to which the CSB interaction
brings about almost no contribution, because there is
one proton and one neutron outside the α core and theΛ n and Λ p CSB interactions cancel each other out.
The calculated BΛ s are 5.16 MeV and 5.44 MeV for7
He
and 7Λ Be, respectively. The CSB interaction works
Λ
repulsively (+0.20 MeV) and attractively (−0.20 MeV)in the 7Λ He and 7Λ Be cases, respectively. Therefore, ourresult indicates that if the experimental energy resolution is as good enough as less than 0.2 MeV, the CSB
effect could be observed in these cases.
References
1) A. Gal, Adv. Nucl. Sci. 8, 1 (1977).
2) B. F. Gibson and E. V. Hungerford III, Phys. Rep. 257,
349 (1995).
3) H. Tamura et al., Phys. Rev. Lett. 84 5963 (2000).

2.0

2

+

0

α +n+n0.0

α +n+n+ Λ+

α +n+pα +n+p+Λ

0.79

α +p+p&A+p+p+Λ

–0.12

–1.03

MeV)

0

Λ=5.36

MeV

–2.0

–3.0

+

0

MeV

–1.0

0.82

1 MeV
B Λ=5.2
MeV)(Exp. 5.16

+

1.77

B Λ=5.28

2+(Exp. 5.26

1.0

E(MeV)

This study is focus on the structure of a multipletof Λ hypernuclei such as 7Λ He, 7Λ Li and 7Λ Be; this multiplet is specified by an isospin T , An important subject related to the isospin multiplet of Λ hypernuclei
is the charge symmetry breaking (CSB) component in
ΛN interactions. The most reliable evidence of the
CSB interaction appears in the Λ binding energies
BΛ of the A = 4 members with T = 1/2 (4Λ He and4Λ H). The CSB effects are attributed to the difference∆CSB = BΛ (4Λ He) − BΛ (4Λ H); the experimental valuesof ∆CSB are 0.35 ± 0.06 MeV and 0.24 ± 0.06 MeV
for the ground (0+ ) and excited (1+ ) states, respectively. In the p-shell region, there exist mirror hypernuclei such as the T = 1 multiplet with A = 7 (7Λ He,
7∗
7
Λ Li , and Λ Be). Historically, some authors mentioned
CSB effects in these p-shell Λ hypernuclei1,2) . However, there is no microscopic calculation of these hypernuclei taking account of the CSB interaction.
In this study, we investigate A = 7 hypernuclei
within the framework of an α + Λ + N + N four-bodymodel so as to take account of the full correlations
between all the constituent baryons. Two-body interactions among constituent particles are chosen so as
to reproduce all the existing binding energies of thesubsystems (αN, αΛN, αΛ,etc). Our analysis is performed systematically for ground and excited states ofαΛN N systems with no more adjustable parametersin this stage, so that these predictions offer important
guidance for the interpretation of the upcoming hypernucleus experiments such as the 7 Li(e, e K + ) 7Λ He
reaction at Jlab.
First, in Fig. 1, we show the energy spectra of A = 7
hypernuclei without the CSB interaction. The groundstate energy of 7Λ He is −6.39 MeV with the respect tothe α + n + n + Λ four-body breakup threshold. ¿From7
7
Λ Li to Λ Be, as the number of protons increases, theCoulomb repulsion becomes more and more effective.
Recently in KEK-E419 experiment3) , they produced
the T = 1, 1/2+ state of 7Λ Li. The observed valueof BΛ =5.26 MeV is in good agreement with our calculated value 5.28 MeV. In the case of 7Λ Be, there are
the old emulsion data giving BΛ =5.16 MeV. This value
should be compared with our obtained value 5.21 MeV.
Then, the BΛ value in the ground 1/2+ state of 7Λ He

Fig. 1. The calculated energy levels of 6 He, 7Λ He, 6 Li∗ , 7Λ Li,
6
Be and 7Λ Be with spin-spin and spin-orbit ΛN interactions. The CSB potential is not included in the calculated energies of A = 7 hypernuclei.

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Shell-model study of Σ-mixing in hypernuclear isotopes
A. Umeya and T. Harada� 1[Nuclear structure, shell model, hypernuclei]|Dµ |2 (%)

Table 1. Calculated values of Σ-mixing probability PΣ and
One of the important subjects in strangeness nuclear
energy shift ∆ϵ for Λ Li isotopes.
1)
physics is neutron-rich Λ hypernuclei. It is expectedthat a Λ hyperon acts as a glue in the nuclei that are
J π T Z N PΣ (%) ∆ϵ (MeV)beyond the neutron drip line, and knowledge of the
7
1+
0
3
3
0.098
0.085
Λ Li
2
behavior of hyperons in an environment with excess
8
1
1�
3
4
0.172
0.139
Λ Li
2
neutrons will signiﬁ cantly inﬂ uence our understanding
9
3+
1
3
5
0.211
0.172
Λ Li
2
of neutron stars because the addition of hyperons soft10
�
3
Li
1
3
6
0.345
0.280
Λ
2
ens the Equation of State.2) Recently, Akaishi et al.3,4)
suggested that coherent ΛN -ΣN coupling was important in light Λ hypernuclei, and a shell-model study5)
0.30
showed that the Σ-mixing probability and the energy
shift due to the ΛN -ΣN coupling in the 10
0.20
Λ Li groundstate are higher than those in 7Λ Li. The purpose of
0.10
our study is to theoretically clarify the structure ofneutron-rich Λ hypernuclei by using a shell model. In
0.00
PSfrag replacements
this study, we investigate the structure of Λ Li hypernu60
70
80
90
100
clei in which A is in the range 7–10 by focusing on theE(ψΣµ ) − E(ψΛg.s. ) (MeV)Σ-mixing probabilities and energy shifts in shell-model
calculations for which the ΛN -ΣN coupling eﬀ ect is
Fig. 1. ΛN -ΣN coupling strength |Dµ |2 of the Σ-nuclear
taken into consideration.
states in the ground state of 10
Λ Li.
In the conﬁ guration space for Λ hypernuclei in whichΛN -ΣN coupling exists, the Hamiltonian is given as
H = HΛ +HΣ +VΛΣ , where HΛ and HΣ are the HamilΛ
eigenstates |ψµΣ ⟩ and the Λ-nuclear ground state |ψg.s.
⟩.
tonians in the Λ and Σ conﬁ guration spaces, respecSeveral
Σexcitedstatesconsiderably
contributetotively. VΛΣ denotes the two-body ΛN -ΣN couplingthe Σ-mixing. These contributions are coherently eninteraction. We can write a Λ Li eigenstate as
hanced by conﬁ guration mixing, which is caused by∑∑the ΣN interaction, leading to the enhancement of the|Λ Li⟩ =Cν |ψνΛ ⟩ +Dµ |ψµΣ ⟩,(1)
Σ-mixing probability. It is shown that the nature ofνµthe Σ-nuclear states plays an important role in theΛN -ΣN coupling. Such a Σ admixture is required inwhere |ψνΛ ⟩ and |ψµΣ ⟩ are eigenstates of HΛ and HΣ , rea DWIA calculation10) to explain the (π � , K + ) specspectively. We construct wave functions in the p-shell
10
trum of 10
B target at 1.2 GeV/c.11)
model space for the nucleon part and the s-shell modelΛ Li on a
space for the hyperon part. In the case of NN eﬀ ecReferences
tive interaction, we consider the Cohen-Kurath (8–16)
1) L. Majling: Nucl. Phys. A 585, 211c (1995).
2BME.6) We use radial integrals5) in the case of YN
2) M. Baldo, G. F. Burgio, and H.-J. Schulze: Phys. Rev.
eﬀ ective interaction, which is given in Refs.7,8) and is
C 61, 055801 (2000).
9)
based on the NSC97e,f potentials.
3) Khin Swe Myint, T. Harada, S. Shinmura, and Y.
Table 1 lists the calculated values of Σ-mixing probAkaishi: Few-Body Syst. Suppl. 12, 383 (2000).
abilities and energy shifts for the Λ Li hypernuclei. We4) Y. Akaishi, T. Harada, S. Shinmura, and Khin Swe
observe that the Σ-mixing probabilities and energy
Myint: Phys. Rev. Lett. 84, 3539 (2000).
shifts are of the order of 10� 1 % and 10� 1 MeV, respec5) A. Umeya and T. Harada: Phys. Rev. C 79, 024315
tively, and increase with the neutron number. The Σ(2009).
mixing probability is approximately 0.35% and the en6) S. Cohen and D. Kurath: Nucl. Phys. 73, 1 (1965).
7) D. J. Millener: Lect. Notes. Phys. 724, 31 (2007); Nucl.
ergy shift is approximately 0.28 MeV for the neutronPhys. A 804, 84 (2008).
rich 10Li
groundstate;
thesevalues
are
about
three
Λ
8) D. J. Millener (private communication).
times those of 7Λ Li.
9) Th. A. Rijken, V. G. J. Stoks, and Y. Yamamoto: Phys.
Figure 1 shows the calculated values of the strengthRev. C 59, 21 (1999).
2|Dµ | of the ΛN -ΣN coupling between the Σ-nuclear
� 1

Research Center for Physics and Mathematics, Osaka
Electro-Communication University- 39 -

10) T. Harada, A. Umeya, and Y. Hirabayashi: Phys. Rev.
C 79, 014603 (2009).
11) P. K. Saha et al.: Phys. Rev. Lett. 94, 052502 (2005).

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Complex-scaled CDCC method for nuclear breakup reactions
M. Takashina,∗1,∗2 T. Myo,∗3,∗2 Y. Kikuchi,∗4 Y. Hirabayashi,∗5 and K. Kato∗4[Complex scaling method, CDCC, breakup reaction]

∗1

∗2
∗3
∗4
∗5

Graduate School of Medicine, Osaka University
RCNP, Osaka University
General Education, Faculty of Engineering, Osaka Instituteof Technology
Division of Physics, Graduate School of Science, Hokkaido
University
Information Initiative Center, Hokkaido University- 40 -

0.6

58

d+ Ni @ Ed = 80 MeV
l = 0, J = 17

0.4

PS−CDCC

2|S|

Nuclear-reaction experiments have revealed various
exotic phenomena of unstable nuclei. The study of thenuclear-breakup process is very important in the caseof reactions induced by light unstable nuclei becauseof the weak binding nature of these nuclei. When the
projectile nucleus breaks up to form a two-body or athree-body system, it is necessary to solve the threebody or the four-body scattering problem, respectively,
including the target nucleus. Although it is difficult toaccurately solve the three- and four-body scattering
problems, many authors have attempted to describe
breakup reactions.
The continuum-discretized coupled-channel (CDCC)
method is known to be useful in analyzing the nuclear
breakup processes1) . In CDCC, the breakup continuum states of the projectile nucleus are discretized in
an appropriate manner. Recently, pseudo-state (PS)
CDCC method was developed; using this method thecontinuous S-matrix elements can be calculated by introducing a smoothing function when the projectile
breaks up and forms a two-body system2) . It also becomes possible to include the three-body breakup effects of projectile like 6 He in analysis of elastic scattering3) . More recently, several new methods for obtaining smoothing functions have been developed4) ; thesemethods can be used to study three-body breakup.
In the present study, we propose another approach.
We consider applying the complex-scaling method5)
to the CDCC [ complex-scaled (CS) CDCC ] method
such that only the internal coordinate and the momentum of the projectile are complex-scaled. The expected advantages of CS-CDCC are as follows: (1)In spite of the discretization, exact continuum level
density can be obtained7) , and then, the continuous
S-matrix elements can also be calculated without introducing any smoothing function. (2) In the complexscaling method, the three-body scattering problem canbe properly solved6) . (3) The resonance state is strictly
separated from the continuum states; as a result, theCS-CDCC method is more advantageous for investigating the reaction mechanism than the ordinary
CDCC method5) .
We derive the CS-CDCC equation for the breakup
reaction d → p + n on a 58 Ni target at an inci-

CS−CDCC
o

θ=5

0.2

θ = 1000

0.5−1k (fm )o1

Fig. 1. Squared modulus of S-matrix elements as a functionof k.

dent energy of Ed =80 MeV. The potential parameters
are taken from Ref.2. For simplicity, we neglect thedeuteron states corresponding to =2, the Coulomb
potential between the proton in deuteron and 58 Ni, andthe imaginary potentials of the p-58 Ni and n-58 Ni systems. Further theoretical study is necessary to accountfor the imaginary potentials. The CS-CDCC equation
is solved by applying the proper boundary condition.
Since the calculated S-matrix elements are complexscaled, they are projected onto the real-energy axis, asin the calculation of the strength function in Ref.6.
Figure 1 shows the calculated S-matrix element for
total angular momentum J=17 as a function of the relative momentum k between the proton and the neutron
in a deuteron. The open circles represent the result of
the ordinary PS-CDCC calculation, and the solid anddotted curves represent the results of the CS-CDCC
calculations at the scaling angles θ of 10◦ and 5◦ , respectively. It is found that the results of the CS-CDCC
calculations at a scaling angle of 10◦ are almost equivalent to those of PS-CDCC. As expected, the dottedcurve exhibits oscillatory behavior. This result indicates that CS-CDCC can be used for analyzing thenuclear breakup reactions. It should be noted thatthe exact S-matrix elements can be obtained using CSCDCC without the need for any smoothing function.
References
1) M. Kamimura et al.: Prog. Theor. Phys. Suppl. 89, 1(1986).
2) T. Matsumoto et al.: Phys. Rev. C 68, 064607 (2003).
3) T. Matsumoto et al.: Phys. Rev. C 70, 061601 (2004).
4) T. Matsumoto et al.: Prog. Theor. Phys. 121, 885(2009).
5) J. Aguilar and J. M. Combes: Commun. Math. Phys.
22, 269 (1971); E. Balslev and J. M. Combes: ibid. 22,
280 (1971).
6) S. Aoyama et al.: Prog. Theor. Phys. 116, 1 (2001).
7) R. Suzuki et al.: Prog. Theor. Phys. 113, 1273 (2005).

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Long-Range Correlations and the Quenching of Spectroscopic Factors
C. Barbieri,∗This work considered the valence orbits around theclosed-shell 56 Ni isotope and investigated how diﬀerent
types of correlations quench their spectroscopic factors(SFs). The single-particle Green’s function1) was calculated in Refs.2,3) within a large basis, including up
to 10 oscillator shells. This space is large enough toinclude long-range correlations (LRC) eﬀects directly.
Short-range correlations (SRC) from outside this space
were accounted for by using a G-matrix.
The LRC were treated in the Faddeev random
phase approximation (FRPA), which includes particlevibration coupling in all possible channels. This leads
to the spectral function depicted in Fig. 1 where thesingle particle states of the valence orbits in the pf shell
are evident. Their SFs are obtained from
�
�
1
�
,
(1)
Zα =
�
⋆
∂Σ (ω)
1 − α̂α̂ �
A±1
A
∂ω

ω=±(Eα

57

Ni:

55

Ni:

ν1p1/2
ν0f5/2
ν1p3/2
ν0f7/2

SRC
0.96
0.95
0.95
0.95

Exp.5)

0.58(11)

Table 1. Quenching of neutron SFs around 56 Ni, as obtained in a large space with up to 10 oscillator shells.
The column “SRC7’ includes only SRC eﬀects in calculating Eq. (1). “S+LRC” is the full FRPA result withboth SRC and LRC from particle-vibration couplings.
The column “FRPA+∆Zα ” includes the correction for
additional conﬁguration mixing estimated in Tab 2.

−E0 )where Σ⋆α̂α̂ (ω) ≡< ψ̂α |Σ⋆ (ω)|ψ̂α > is the matrix element of the self-energy calculated for� the overlap function itself but normalized to unity ( dr |ψ̂α (r)|2 = 1).

10 osc. shells
S+LRC FRPA+∆Zα
0.63
0.61
0.59
0.55
0.65
0.62
0.72
0.69

57

Ni:

55

Ni:

ν1p1/2
ν0f5/2
ν1p3/2
ν0f7/2

FRPA
0.79
0.79
0.82
0.89

pf space
SM
0.77
0.75
0.79
0.86

∆Zα
-0.02
-0.04
-0.03
-0.03

Table 2. Comparison of SFs obtained with the FRPA andthe SM (up to 6p6h conﬁgurations), for the pf model
space. The diﬀerences (∆Zα ) estimate the importanceof conﬁguration mixing beyond 2p1h ans 2h1p.

Fig. 1. Single-particle spectral distribution for neutrons in
56
Ni 2,3) . Energies above (below) EF are for transitions
to excited states of 57 Ni (55 Ni). The quasiparticle statesclose to the Fermi surface are clearly visible.

The formalism of Ref.2) allows to separate the contributions of SRC and LRC to the derivative in Eq. (1).
The SFs obtained for neutron orbits are given in theﬁrst two columns of Tab. 1 for the chiral N3LO interaction4) : LRC are responsible for most of the quenching. In order investigate the importance of conﬁguration mixing near the Fermi surface (not included in the
FRPA formalism), both shell-model (SM) and FRPA
were also calculated in the sole pf shell model space.
Tab. 2 shows that the correction due to extra correlations in the SM is almost negligible in this case. The
total results after adding this correction is given Tab. 1†∗

Condensed from the article in Ref.3)
Theoretical Nuclear Physics Laboratory, RIKEN Nishina
Center, Japan- 41 -and nicely agree with the experiment. Similar conclusions were obtained for 48 Ca as well3) .
It remains clear that conﬁguration mixing (that is,SM) eﬀects have an important impact on open shell
nuclei where they can determine the relative SFs (i.e.,
the fragmentation pattern at low energy)6) . On theother hand, the overall quenching of absolute SFs requires the coupling to collective modes at higher energies which cannot be approached by standard SM
calculations. For valence orbits around shell closures,
particle-vibration coupling was found to be the main
mechanism. Proper calculations of this eﬀect may pave
a new way for understanding eﬀective charges and interactions in the SM.
References
1) W. H. Dickhoﬀ and D. Van Neck, Many-Body Theory
Exposed! (World Scientiﬁc, Singapore, 2005).
2) C. Barbieri and M. Hjorth-Jensen , Phys. Rev. C 79,
064313 (2009).
3) C. Barbieri , Phys. Rev. Lett. 103, 202502 (2009).
4) D. R. Entem et al., Phys. Rev. C 68, 041001(R) (2003).
5) K. L. Yurkewicz et al., Phys. Rev. C 74, 024304 (2006).
6) M. B. Tsang et al., Phys. Rev. Lett. 102, 062501 (2009).

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Contribution of core polarization for electric quadrupole moments ofneutron-rich nuclei in the island of inversion†
Kenichi Yoshida[Nuclear structure, Density functional theory, Unstable nuclei]iλj

are obtained by diagonalizing the Hamiltonian��Ei β̂i† β̂i +h̄ωλ B̂λ† B̂λ + Ĥcouple .
Ĥ =
i

(2)

λ

Here, β̂i† and B̂λ† are creation operators of the Bogoliubov quasiparticles and the QRPA phonons respectively. The Bogoliubov quasiparticles have excitationenergy of Ei . The QRPA phonons with excitation energy h̄ωλ represent the collective vibrations, including
low-lying states and giant resonances. The vacuum |0�
represents the ground state of the neighboring evensystem.
In the present calculation, 31 Al, 33 Al, and 35 Al aredescribed as a proton single-hole state (πd5/2 )−1 coupled to a 32 Si,34Si, and 36 Si core to form I π = 5/2+.
Figure 1 shows the ground-state Q moments of Al isotopes. The calculated Q moment of 31 Al agrees wellwith the new experimental value5) , which is denoted asexp(2) in the ﬁgure. The diﬀerence between the values
denoted by ﬁlled squares and diamonds represents thecore polarization eﬀect.
The predicted Q-moment of 33 Al also agrees wellwith the experimental value3) . The diﬀerence between
the value denoted as GR by the ﬁlled circle and thevalue denoted by the diamond represents the core polarization eﬀect originated from the coupling to the†Condensed from article in Phys. Rev. C 79, 054303 (2009).

- 42 -

16
Q moment of Al (efm2)

At present, the small excitation energy of the ﬁrst+
2+ state and striking enhancement of B(E2; 0+
1 → 21 )32
1)
in Mg are being actively studied with reference tothe onset of the quadrupole deformation and the disappearance of the spherical magic number N = 20.
The electric quadrupole moment (Q moment) represents the deviation from a sphere. The Q moment isdirectly related to the deformation property of the nucleus, and hence it is desirable to experimentally andtheoretically investigate the Q moment of neutron-richnuclei around N = 202) . Recently, the Q moment of
33
Al was measured at GANIL3) .
In order to study the Q moments of neutron-rich
Al isotopes in the vicinity of the “island of inversion,”
we carry out particle-vibration coupling (PVC) calculation on the basis of the Skyrme energy-density functional; the self-consistent HFB + quasiparticle-RPA(QRPA) that was developed recently4) .
The wave functions of the odd-A system,��
c0i β̂i† |0� +c1λj B̂λ† β̂j† |0�,
(1)
|φ� =

14
12
10

exp(2)
exp(1)

exp(3)
no pairing
GR

8
6
18

20
Neutron number

22

Fig. 1. Comparison of Q moments of 31,33,35 Al determinedfrom experiments (open triangles) and by calculations
with/without pair correlation (filled squares/circles).
The calculation that includes only the giant quadrupole
resonance (GR) is also shown. Filled diamonds represent the Q moment of the proton 1d−1
5/2 state. The experimental values, exp(1), exp(2), and exp(3), are obtained from Ref.2) , Ref.5) and Ref.3) , respectively.

giant quadrupole resonance only. This is about 70% of
the observed value. Hence, the further enhancement isrequired to explain the experimental Q-moment. The
coupling to the low-lying 2+ state brings about thisenhancement.
Note that calculations indicate the core nucleus tobe spherical. However, the narrowing of the N = 20
shell gap as shown in Fig. 2 in Ref.6) , and the neutron
pairing across N = 20 that results in a neutron 2p −2h
conﬁguration admixture, play a crucial role in explaining the experimental value. When the neutron pairing
is not considered, the enhancement of the Q moment
resulting from the coupling to the low-lying 2+ state isabout half as shown in Fig. 1 (the ﬁlled circle denoted
as “no pairing”).
The results of the calculation indicate the weakeningof the N = 20 magicity in 33 Al. However, this weakening is insuﬃcient to drive permanent nuclear deformation. Therefore, we consider that 33 Al is located on
the border of the ”island of inversion.”
References
1) T. Motobayashi et al: Phys. Lett. B 346, 9 (1995).
2) D. Nagae et al: Phys. Rev. C 79, 027301 (2009).
3) T. Nagatomo et al: Eur. Phys. J. A 42, 383 (2009).
4) K. Yoshida et al: Phys. Rev. C 78, 064316 (2008).
5) M. De Rydt et al: Phys. Lett. B 678, 344 (2009).
6) M. Yamagami et al: Phys. Rev. C 69, 034301 (2004).

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Clustering and superdeformation in sd-shell region
Y. Taniguchi[nuclear structure, clustering, superdeformation]
Studies on the structures in 28 Si and 40 Ar have been
focused on superdeformation and clustering; deformedbasis antisymmetrized molecular dynamics (AMD)and the generator coordinate method (GCM) havebeen used in these studies.
A deformed-basis AMD wave function is a Slater determinant of triaxially deformed Gaussian wave packets. By varying the energy while applying constraints,
the wave functions of various structures were obtained.
Parity and angular momentum before and after energy
variation, respectively, were projected. By superposing those obtained wave functions after parity and angular momentum projections, Hamiltonian and norm
matrices were diagonalized (GCM).
1

α clustering and superdeformation in 28 Si

It was proposed to develop α–24 Mg cluster structures by carrying out the 24 Mg(6 Li, d) reaction1) .
By applying constraints to the cluster distance andquadrupole deformation during variational calculation,
GCM basis wave functions with various structures such
as α–24 Mg and 12 C–16 O cluster structures and deformed structures are obtained. The superpositionof these basis wave functions yields an oblate groundstate band, a β vibration band, a normal-deformed
prolate band (ND), and a superdeformed band (SD).
The ND and SD bands correspond to a high percentage of the 12 C–16 O and α–24 Mg cluster components,
respectively. The results also suggest the presence of
two excited bands with the developed α–24 Mg cluster
structure; the intercluster motion and the 24 Mg-cluster
deformation play important roles in this cluster structure.
The details of this work is reported in Ref. 2. This
was a collaborative study by Y. Taniguchi of RIKEN,
Y. Kanada-En’yo of Kyoto University, and M. Kimuraof Hokkaido University.
2

ground state band was determined. This SD band includes a K π = 2+ sideband due to the triaxiality. The
calculated values of the quadrupole electric transition
strength of the SD band agree well with the experimental values. The present results suggest that the ex+perimentally observed J π = 2+
5 (3.92 MeV), 3 (4.23
MeV), and (2, 3, 4)+ (5.17 MeV) states are membersof the K π = 2+ SD band. It is important to consider
triaxiality in order to understand deformations in lowlying states.
The details of this work is reported in Ref. 4. This
was a collaborative study by Y. Taniguchi of RIKEN,
M. Kimura of Hokkaido University, Y. Kanada-En’yoof Kyoto University, K. Ikeda of RIKEN, H. Horiuchi
of Osaka University, and E. Ideguchi of the Universityof Tokyo.
References
1) K. P. Artemov, M. S. Golovkov, V. Z. Goldberg,
V. I. Dukhanov, I. B. Mazurov, V. V. Pankratov,
V. V. Paramonov, V. P. Rudakov, I. N. Serikov,
V. A. Solovev, and V.A. Timofeev: Sov. J. Nucl. Phys.
51, 777 (1990).
2) Y. Taniguchi, Y. Kanada-En’yo, and M. Kimura: Phys.
Rev. C 80, 044316 (2009).
3) E. Ideguchi, S. Ota, T. Morikawa, M. Oshima,
M. Koizumi, Y. Toh, A. Kimura, H. Harada, K. Furutaka, S. Nakamura, F. Kitatani, Y. Hatsukawa,T. Shizuma, M. Sugawara, H. Miyatake, Y.X. Watanabe, Y. Hirayama, and M. Oi: Phys. Lett. B 686, 18(2010).
4) Y Taniguchi, Y Kanada-En’yo, M Kimura, K Ikeda,
H Horiuchi, and E Ideguchi: arXiv:1002.4495 (2010).

Triaxial superdeformed states in 40 Ar

Very recently, the presence of an SD band corresponding to the J π = 0+
2 state (2.12 MeV) was experimentally conﬁrmed up to the J π = (12+ ) state3), but theoretical studies on the SD states have notbeen conducted. GCM basis wave functions were obtained by considering the energy variation by applying a constraint on the quadrupole deformation parameter β, and other quantities such as the triaxiality
γ were optimized by energy variation. By performing the GCM calculation, an SD band just above the- 43 -

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Examination of non-monotonic shell evolution beyond N = 28 on thebasis of the β-decay of K isotopes
Y. Utsuno,∗1 T. Otsuka,∗2∗3 B.A. Brown,∗4∗3 M. Honma,∗5 and T. Mizusaki∗6[Nuclear structure, shell model, unstable nuclei]

References
∗1
∗2
∗3
∗4

Advanced Science Research Center, Japan Atomic Energy
AgencyDepartment of Physics and Center for Nuclear Study, University of Tokyo
National Superconducting Cyclotron Laboratory, Michigan
State University
Department of Physics and Astronomy, Michigan State Uni-

- 44 -

2

SPE (MeV)0π0d3/2π1s1/2-2

Shell Model

-4
-6
-8

Woods-Saxon

π0d5/2
20

22

24

26

N

28

30

32

Fig. 1. Proton single-particle energies of 1s1/2 and 0d5/2
measured from 0d3/2 as a function of the neutron
number. Solid lines and dashed lines represent theshell-model and Woods-Saxon potential, respectively.
Filled circles denote experimentally observed singlehole states in corresponding K isotopes.
51

K

4

51

Ca

-

log f0t = 6.22

7/2

3

8.22

3/2

Ex (MeV)

One-body potentials such as the Woods-Saxon potential have been successful in describing the shellstructure of near-stable nuclei. The one-body picture always gives a smooth and monotonic change inthe shell structure as the number of nucleons varies.
On the other hand, it has recently been pointed outthat the monopole interaction, an angular-momentumaveraged interaction between two orbits, could cause a
different behavior in very neutron-rich regions.1) It isthus of great interest to find such a manifestation ofshell evolution.
In this study, we explore the proton shell structure;we perform shell-model calculations using amonopole-based universal interaction picture proposed
recently.2) Many cases of single-particle evolution in
exotic nuclei have been successfully explained by considering a simple force consisting of a Gaussian force
as the central force and a π + ρ meson-exchange force
as the tensor force.2) In the present study, the parameters in expression for the central force given in Ref.
2 are modified to better fit to the central part of the
GXPF1 interaction.3) Part of the work was carried out
as a RIKEN-CNS collaborative project on large-scale
nuclear structure calculations.
The shell-model interaction considered in this study
predicts the proton shell evolution to be quite different from that predicted by the potential picture, as
shown in Fig. 1. The 1s1/2 orbit moves above 0d3/2
at N = 28, and it goes down below 0d3/2 at N = 32,
where 1p3/2 is fully filled. This is an example of nonmonotonic shell evolution, which is never given by the
one-body picture.
If non-monotonic shell evolution occurs, the groundstate of 51 K must be 3/2+ . Although there is no direct
measurement of the spin/parity of 51 K, we have foundthat it is highly likely that the ground state is 3/2+ .
Our finding is supported by the good agreement between the β-decay properties observed experimentallyand those obtained theoretically (Fig. 2). The experimental decay pattern cannot be explained from the
1/2+ state of 51 K.

8.11

5/2

8.13

1/2

-

6.18

3/2

-

6.4(1)2-

10

6.0(1) 3/2-

Exp.

Calc.

Fig. 2. Comparison of log f0 t values of β decay from 51 K
to 51 Ca obtained experimentally4) and by shell-model
calculations in which the ground state of 51 K is assumed
to be 3/2+ .

1) T. Otsuka, R. Fujimoto, Y. Utsuno, B.A. Brown,
M. Honma, and T. Mizusaki: Phys. Rev. Lett. 87,
082502 (2001).
2) T. Otsuka, T. Suzuki, M. Honma, Y. Utsuno, N. Tsunoda, K. Tsukiyama and M. Hjorth-Jensen, Phys. Rev.
Lett. 104, 012501 (2010).
3) M. Honma, T. Otsuka, B.A. Brown and T. Mizusaki:
Phys. Rev. C 69, 034335 (2004).
4) F. Perrot et al.: Phys. Rev. C 74, 014313 (2006).

∗5∗6

versity
Center for Mathematical Sciences, University of Aizu
Institute of Natural Sciences, Senshu University

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Shell-model description of N =Z pfg-shell nuclei
M. Honma,∗1 T. Otsuka,∗2,∗3 T. Mizusaki,∗3 and M. Hjorth-Jensen∗4[NUCLEAR STRUCTURE, shell model]
In upper pf-shell nuclei, various interesting phenomena have been discovered recently, such as the development of nuclear deformation, the coexistence of different shapes near the ground state, the formation ofisomeric states, the double β decay, and so on. In
neutron-rich nuclei, the shell structure can be different from that of the stable nuclei, which reveals a new
aspect of the nuclear tensor force1) . For deeper understanding and reliable predictions of these phenomena,a unified theoretical framework has been desired.
We have developed an effective interaction JUN45
for shell-model calculations in the model space consisting of valence orbits 1p3/2 , 0f5/2 , 1p1/2 and 0g9/2 assuming an inert 56 Ni core (f5pg9-shell). Here, we modified a realistic interaction (renormalized G-matrix2)
derived from the Bonn-C potential) through the iterative fitting calculations to a body of experimental energy data as we did in the derivation of the GXPF1
interaction for the pf-shell3) . In the latest iteration,
we have attained the rms error of 185 keV for 400 datataken from 87 nuclei with masses A=63-96.
In N =Z nuclei, since protons and neutrons occupy
the same orbit, the strong proton-neutron interaction
works efficiently, which can develop significant collectivity. In the derivation of the JUN45 interaction,
we excluded the experimental data of nuclei aroundN ∼Z∼40 region for the fit in order to avoid possible
difficulties for describing such collectivity due to thelimited model space. Therefore, it is interesting to examine to what extent we can explore this region withthe f5pg9-shell space.
As an example, we consider 68 Se (N =Z=34), forwhich the shape coexistence has been predicted by
the deformed potential model. Experimental observation5,6) is in fact consistent with the oblate groundstate band, which is crossed by an excited band withprolate shape at around the spin J∼8. As shown in
Fig.1, we have obtained two low-lying bands on top of+
the 0+
1 and the 02 states. The calculated quadrupole+
2
moment for the 2+
1 is +44efm , and that for the 22
2state is −41efm . This indicates that the ground bandshows the oblate shape, while the excited band is prolate, which is consistent with the experimental findings. However, the calculated moment of inertia is
†
∗1

∗2

∗3

∗4

Condensed from the article in Phys. Rev. C 80, 064323/136 (2009)
Center for Mathematical Sciences, University of Aizu
Department of Physics and Center for Nuclear Studies, University of Tokyo
Institute of Natural Sciences, Senshu University
Department of Physics and Center of Mathematics for Applications, University of Oslo

- 45 -

Fig. 1. Comparison of energy levels between the experimental data and the shell-model results for 68 Se. The
width of the arrow drawn in the experimental part corresponds to the relative γ-ray intensity, while it stands
for the relative B(E2) values in the theoretical part.
Experimental data are taken from Refs.5,6) . The shellmodel results are obtained by using the efficient shellmodel code MSHELL4) .

somewhat too small especially in the prolate band. As
a result, the crossing with the oblate band never occurs. This indicates the insufficient collectivity for the
prolate deformation within the present model space.
The calculated occupation number of the g9/2 orbit
is almost constant within each band. It is about 1.0,
2.3, and 4.1 for the low spin (J=0∼8), intermediate
spin (J=10∼14), and high spin (J=16∼22) band, respectively. Thus, the higher spin bands are generated
by successive promotions of nucleons into the g9/2 orbit. Considering the reasonable overall agreement between the experimental data and the shell-model results, we can expect that the JUN45 successfully describes the single-particle properties related to the g9/2
orbit in the deformed mean potential.
References
1) T. Otsuka, et al.: Phys. Rev. Lett. 95, 232502 (2005).
2) M. Hjorth-Jensen et al.: Phys. Rep. 261, 125 (1995).
3) M. Honma, et al.: Phys. Rev. C 65, 061301(R) (2002);
Phys. Rev. C 69, 034335 (2004).
4) T. Mizusaki: RIKEN Accel. Prog. Rep. 33, 14 (2000).
5) S. M. Fischer et al.: Phys. Rev. Lett. 84, 4064 (2000).
6) S. M. Fischer et al.: Phys. Rev. C 67, 064318 (2003).

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Newly developed program for the Monte Carlo shell model
N. Shimizu,� 1 Y. Utsuno,� 2 T. Abe,� 1 and T. Otsuka� 1,� 3[nuclear structure, shell model, computational physics]
The Monte Carlo shell model method (MCSM)
has been developed since 19951) in order to avoid
the diﬃculty of diagonalizing the Hamiltonian matrix
which has very large dimensions in the nuclear shellmodel. The MCSM has been successfully applied in
the nuclear-structure study up to the medium-heavy
nuclei, including exotic nuclei2) by using the powerful
Alphleet-1 and Alphleet-2 computer clusters.
As its applicability is enlarged, the MCSM code has
been extended accordingly. For instance, the MCSM
was recently used to perform ab initio calculations.
Nevertheless, the original MCSM code has some limitations that restrict its use in more up-to-date nuclearstructure calculations. In particular, it can handle onlyisospin-conserving interactions. In most ab initio calculations, the isospin symmetry is not assumed to beconserved. If we consider the portability of the code,
the original code is not expected to run on most stateof-the-art supercomputers because the Parallel Virtual
Machine (PVM)3) , which is decreasing in popularity,
is used for parallel computing. It is not easy to overcome these limitations by locally modifying the existing code. This is partly because the original MCSM
code was coded in Fortran 77, in which it becomes increasingly diﬃcult to develop well-structured code as
the size of the code increases.
In order to overcome these limitations and fully utilize modern computational technologies, we initiateda project to write a novel MCSM code from scratch.
The new MCSM code is equipped with the following
features:(1) The code is written in modern Fortran 95.
(2) Hybrid parallel computing based on Message
Passing Interface library (MPI)4) and OpenMP
is used.
(3) It can handle isospin-breaking interaction.
(4) It can evaluate many physical quantities which
are important in ab initio calculations (e.g. rootmean-square radius).
(5) The code incorporates a new algorithm for the
calculation of the Hamiltonian matrix elements.
At the present stage, the new code can calculate
the Hamiltonian matrix elements using the angularmomentum and parity projection for any Slater determinant basis, and the eigenvalue of the Hamiltonian
can be obtained with those matrix elements. The codefor generating and selecting bases is to be developed.
� 1
� 2
� 3

Department of Physics, University of TokyoJapan Atomic Energy Agency
Center for Nuclear Study, University of Tokyo- 46 -

Since calculating the Hamiltonian matrix element is
the most time-consuming part in MCSM, it is worth
examining its computing performance by comparing
with the original code. As a benchmark calculation,
the eigenvalue of the Hamiltonian for the 0+ of 56 Ni
in pf -shell is computed with given ﬁ ve Slater determinants. Angular momentum is fully projected by performing three-dimensional (25 × 25 × 25) integration.
Table 1 shows the computation time on a system withan Intel Xeon E5430 2.66-GHz processor and an Intel
Fortran compiler version 11.1 was used. In Table 1,
codes “orig.”, (A), (B) represent the original MCSM
code, newly developed code without feature (5), andnewly developed code with feature (5), respectively.
Although the new code (A) has the same algorithm as
the original one, its performance is 25% better thanthat of the original code because of feature (1).
code
orig.
(A)
(B)
computation time [sec.]
61.1 46.0 30.5
Table 1. Result of the benchmark test for 56 Ni in the pf shell. See the text for more details.

We wrote the new code (B) so that the Hamiltonian
matrix elements of the two-body interaction are computed by matrix multiplication; here, we exploit thesymmetries of the two-body interaction to reduce thecomputation time. Table 1 indicates that this algorithm results in an improvement of 50% in the performance, and, consequently, the performance of the newcode (B) is superior to that of the original one by afactor of two.
This newly developed code and state-of-the-art supercomputers will enable us to attack p-shell nuclei
and its beyond through ab initio calculations. In addition, the good maintainability of the code makes it
easy for us to incorporate useful functions, for example, a quasi-particle vacuum can be adopted as a basis
wave function5) .
This study is a part of the RIKEN-CNS joint project
for large-scale nuclear-structure calculations.
References
1) M. Honma, T. Mizusaki, and T. Otsuka: Phys. Rev.
Lett. 75, 1284 (1995).
2) T. Otsuka, M. Honma, T. Mizusaki, N. Shimizu, andY. Utsuno: Prog. Part. Nucl. Phys. 46, 319 (2001).
3) http://www.csm.ornl.gov/pvm/4) http://www.mcs.anl.gov/research/projects/mpi/
5) N. Shimizu, T. Otsuka, T. Mizusaki, and M. Honma:
Phys. Rev. Lett. 86, 1171 (2001).

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Microscopic description of oblate-prolate shape mixing in proton-rich
Se isotopes
N. Hinohara, T. Nakatsukasa, M. Matsuo� 1 and K. Matsuyanagi� 2[Nuclear structure, large-amplitude collective motion]

†
� 1
� 2

Condensed from the article in Phys. Rev. C 80, 014305(2009)
Department of Physics, Faculty of Science, Niigata University
Yukawa Institute for Theoretical Physics, Kyoto University- 47 -

momentum.
The results of calculations show that oblate-prolate
shape mixing becomes weak as the rotational angularmomentum increases, and this is a common feature of
all the three isotopes. We have analyzed the dynamical origin of this trend and found that the rotationalenergy plays a crucial role in determining the degree of
localization of the collective wave function in the (β, γ)
plane. The rotational eﬀ ect causing the localization of
the collective wave function may be called “rotational
hindrance of shape mixing.”
0.5

72

βsinγ

0.4

Se

0.3
0.2
0.1
0
0

0.1 0.2 0.3 0.4 0.5

βcosγ
Fig. 1. Collective path for 72 Se obtained by the ASCC
method. The collective path projected onto the (β, γ)
plane is indicated by the solid line on the potential energy surface.
8

72

7
Excitation Energy [MeV]Recent experimental data1) for 70 Se and 72 Se indicate that there is a gradual change in the characterof the ground rotational band from oblate to prolatewith an increase in the angular momentum. The dataalso suggest considerable mixing of the oblate and prolate shapes in the low-lying states of 70 Se and 72 Se.
Since shape mixing is caused by large-amplitude collective motion connecting diﬀ erent shapes, it cannot betheoretically described within the static mean-ﬁ eld approximation or the small-amplitude ﬂ uctuations about
equilibrium shapes.
We investigate the shape coexistence/mixing dynamics in 68 Se, 70 Se, and 72 Se by the adiabatic selfconsistent collective coordinate (ASCC) method2) ; thismethod enables us to extract the collective degrees of
freedom (collective path) that provide information on
the dynamics of large-amplitude shape mixing. As
to the microscopic Hamiltonian, we use the pairingplus-quadrupole model that takes into consideration
the quadrupole-pairing force.
The one-dimensional collective path and the collective Hamiltonian describing the large-amplitude shapevibration are derived fully microscopically. It is foundthat the collective path almost follows the triaxial potential valley, indicating the importance of the triaxial
degree of freedom in these isotopes.
The excitation spectra, B(E2), and spectroscopic
quadrupole moments are calculated by requantizing
the collective Hamiltonian and solving the collective
Schrödinger equation. The basic properties of the two
coexisting rotational bands in the above-mentioned nuclei are found to be well reproduced. In the case of
68
Se, the energy of the calculated 0+
2 state is locatedabove that of 2+
2 state, suggesting that the low-lying
states in 68 Se are in an intermediate situation between
oblate-prolate shape coexistence and the Wilets-Jeanγ-unstable model. This γ-unstable nature is also foundfrom the calculated interband E2-transition probabilities. In the case of 70 Se, we found cross-talks of theE2 transitions between the 2+ and 4+ states associated with a signiﬁ cant change in the localization properties of the wave functions. In the case of 72 Se, the 0+
1
wave function has the maximum value at the oblate deformation, while the prolate character develops in the
ground rotational band with an increase in the angular

6
5

2
1
0

EXP

+

6

(29)

4
3

Se

ASCC

6+
(837)
4+
(639)
+

2
(390)
0+

(543)

(48)

(88)

(19)

(74)
(297)
(337)

4+
(443)
2++(329)0

6+(1220)
4+
(882)
2+
(405)
0+

2+
0+

Fig. 2. Theoretical and experimental excitation spectra
and B(E2) values for low-lying states in 72 Se. The values of the B(E2) are shown in units of e2 fm4 .

References
1) J. Ljungvall, et al.: Phys. Rev. Lett. 100, 102502(2008).
2) M. Matsuo, T. Nakatsukasa and K. Matsuyanagi: Prog.
Theor. Phys. 103, 959 (2000).

1RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Eﬀects of Oblate-Prolate Symmetry Breaking on Triaxial
Deformation Dynamics†
K. Sato,∗1 N. Hinohara, T. Nakatsukasa, M. Matsuo,∗2 and K. Matsuyanagi∗3[Nuclear structure, large-amplitude collective motion, shape coexistence]

†
∗1
∗2
∗3
a)

tures of the excitation spectrum in the (1+3)D model
are identical to those in the (2+3)D model. In particular, the ordering of these eigenstates in the calculations
based on the two models is identical. One can also
see that in both the models, the interband transitions
between the initial and ﬁnal states having equal angular momentum become weaker with increasing angularmomentum. This is caused by the oblate-prolate asymmetry in the moments of inertia. These observations
indicate that the β-γ coupling plays only a secondaryrole and that the major feature of the excitation spectrum is determined by the triaxial deformation dynamics. The γ-dependence of the collective masses and thecollective potential also play an important role.
We performed numerical calculations for the triaxial
deformation dynamics using this model. The results ofthe calculations revealed the following: (1) The relative energy of the excited 0+ state can indicate thepotential shape along the γ direction. (2) Speciﬁc E2transition probabilities are sensitive to the breaking of
the oblate-prolate symmetry. (3) Nuclear rotation may
induce the localization of collective wave functions inthe (β, γ) deformation space.
References
1) A. Bohr and B. R. Mottelson, Nuclear Structure, Vol.
II (W. A. Benjamin Inc., 1975; World Scientiﬁc, 1998).

Excitation Energy [MeV]

In recent years, experimental data suggesting thecoexistence of a ground-state rotational band withan oblate shape and an excited band with a prolate
shape in proton-rich unstable nuclei have been obtained. These observations along with the variety ofshape coexistence phenomena observed in various regions of the nuclear chart stimulate the development of
a nuclear structure theory capable of describing largeamplitude collective phenomena.
In this study, from the viewpoint of oblate-prolate
symmetry and its breaking, we propose a simple model
based on the quadrupole collective Hamiltonian in order to study the dynamics of triaxial deformation in
shape coexistence phenomena. Our model can describe
the axially symmetric rotor model, the γ-unstablemodel, the rigid triaxial rotor model, an ideal situation for the oblate-prolate shape coexistence, andthe intermediate situations between them by varying
a few parameters. It is derived from the well-known
ﬁve-dimensional quadrupole collective Hamiltonian1)
by ﬁxing the β degree of freedom, and thus, it is(1+3) dimensionala) (one dimension for γ vibrationand three dimensions for rotation). Using this model,
we ﬁrst analyze the properties of low-lying states in
the case where the collective masses possess the oblateprolate symmetry; this is done by varying the parameters of the collective potential. Then, we investigate
how the properties of the low-lying states change when
the oblate-prolate symmetry is broken in the collective
masses. We also evaluate the validity of the (1+3)Dmodel by liberating the β degree of freedom, i.e., byusing the (2+3)D model, for the case involving the intermediate situation between the γ-unstable and ideal
oblate-prolate shape-coexistence limits; we are particularly interested in the intermediate situation.
Figure 1 shows the excitation spectra and B(E2)values of the (1+3)D and (2+3)D models for the intermediate situation mentioned above, where the oblateprolate symmetry is broken both in the collective potential and the inertial mass functions; here, the collective potential has an oblate local minimum, andthe prolate local minimum is slightly higher than the
oblate one. The moments of inertia are larger on the
oblate side than on the prolate side. The essential feaCondensed from the article in Prog. Theor. Phys. 123(2010), 129.
Department of Physics, Kyoto University
Department of Physics, Niigata University
Yukawa Institute for Theoretical Physics, Kyoto University
Therefore, we call it the (1+3)D model.

- 48 -

2

50

8+2

4
3

(2+3)D(1+3)D

5

39

8+1
6+1

1

4+1

0

01

2+1

+

183
167

5+1
6+2

15
99
32
29
10 148 3+1
20
4+
110 2+ 89
02255
56 3214
2+2

146 96
100

169

46

8+1
234
6+1
4+1
+

21

+

01

201

60

8+2
225

5+1

20
6+2
119
32
3+1
22
4+2
103
123
0+2
270
+
22

38
11 18376 4014160 126
100

Fig. 1. Comparison of the excitation spectra and E2transition properties in the (1+3)D model (left) withthose in the (2+3)D model (right); the B(E2) values are+
written on the transition arrows, with B(E2; 2+
1 → 01 )normalized to 100.

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Analysis of 78 Ge by generator coordinate method
K. Higashiyama∗1 and N. Yoshinaga∗2[Nuclear structure, generator coordinate method]� (𝜏𝜏 )
�Ψ𝐼𝐼𝜏𝜏 𝑀𝑀𝜏𝜏 𝜌𝜌

〉

=

∑
𝑖𝑖

𝐼𝐼𝜏𝜏
∑

𝐾𝐾𝜏𝜏 =−𝐼𝐼𝜏𝜏

6�〉𝐼𝐼𝜏𝜏 𝑖𝑖 ˆ 𝐼𝐼𝜏𝜏�Φ𝜏𝜏 (𝛽𝛽𝑖𝑖 , 𝛾𝛾𝑖𝑖 ) , (1)ℱ𝐾𝐾𝑃𝑃𝜏𝜏 𝜌𝜌 𝑀𝑀𝜏𝜏 𝐾𝐾𝜏𝜏𝐼𝐼𝜏𝜏𝐼𝐼𝜏𝜏 𝑖𝑖
where 𝑃𝑃ˆ𝑀𝑀
is the spin projection operator, ℱ𝐾𝐾
is𝜏𝜏 𝐾𝐾𝜏𝜏𝜏𝜏 𝜌𝜌
the weight function to be determined by the PGCM,
and 𝑖𝑖 stands for a representative point of deformation(𝛽𝛽𝛽 𝛽𝛽). Then, the many-body wavefunction for an eveneven nucleus can be written as
�
〉 [�
〉 �
〉]
�Ψ𝐼𝐼𝐼𝐼 (𝐼𝐼𝜈𝜈 𝜌𝜌𝜌𝜌𝜋𝜋 𝜎𝜎) = �Ψ(𝜈𝜈) ⊗ �Ψ(𝜋𝜋) (𝐼𝐼) ,(2)
𝐼𝐼𝜈𝜈 𝜌𝜌𝐼𝐼𝜋𝜋 𝜎𝜎 𝑀𝑀

where 𝐼𝐼 is the total spin and 𝑀𝑀 is its projection.
PGCM calculations are carried out for two cases: (i)triaxial deformations with 𝛽𝛽 = 0.2, 0.6, 1.0 and 𝛾𝛾 =10∘ , 20∘ , 30∘ , 40∘ , and 50∘ (15 points); (ii) only axial
deformations with 𝛽𝛽 = 0.0, 0.2, ⋅ ⋅ ⋅, 2.0, 3.0, and 4.0
and 𝛾𝛾 = 0∘ , 60∘ (25 points).
∗1
∗2

78

5

E (MeV)The intriguing properties of the even-even Se and Ge
isotopes in the mass region 𝐴𝐴 ∼ 80 have been investigated in a number of previous experimental and theoretical studies1) . These isotopes belong to a typicaltransitional region that lies between spherical and deformed regions. The structure of their low-lying states
can be attributed to the interplay of rotational andvibrational collective motions. For high-spin states, 𝛾𝛾ray spectroscopy of the near-yrast states in the 𝑁𝑁 = 44
and 46 isotones of Se (80,82 Se) was carried out for deepinelastic reactions2) . Recently, full-ﬂedged shell-model
calculations have been performed on the even-even andodd-mass nuclei in this mass region3) . The shell model
calculations well reproduce the experimental energy
levels and electromagnetic transition rates for the lowlying and high-spin states.
In the present study, we apply the quantum-numberprojected generator coordinate method (PGCM) to78
Ge under the same interaction as used in previous
shell model studies3) . All the four orbitals 𝑔𝑔9/2 , 𝑝𝑝1/2 ,𝑝𝑝3/2 , and 𝑓𝑓5/2 in the major shell of 28 ≤ 𝑁𝑁 (𝑍𝑍) ≤ 50
are considered, and the valence neutrons (protons) aretreated as holes (particles).
In the present scheme, the spins of the neutron andproton systems (𝐼𝐼𝜈𝜈 and 𝐼𝐼𝜋𝜋 ) are projected separately,
and the total spin is constructed by angular momentum coupling. To generate functions �for the PGCM,
we〉employ the intrinsic Nilsson states �Φ𝜏𝜏 (𝛽𝛽𝛽 𝛽𝛽) for theneutron or proton systems (𝜏𝜏 = 𝜈𝜈 or 𝜋𝜋), where (𝛽𝛽𝛽 𝛽𝛽)denotes the deformation parameters. The PGCM
wavefunction for the 𝜌𝜌th state of a spin 𝐼𝐼𝜏𝜏 in neutron
or proton spaces is given by

Ge

4
3

Triaxial

2

Axial

1
0

PGCM
Shell Model
0

2

4

6

8

10

12

0

I (h )

2

4

6

8

10

12

Fig. 1. Excitation energies calculated using the shell model
states (open circles) and the PGCM (crosses) as a function of spin 𝐼𝐼 in 78 Ge.

In Fig.1, energy levels calculated with the shellmodel are compared with those calculated by the
PGCM for 78 Ge. The PGCM results for triaxial andaxial deformations are shown in the left and right panels, respectively. In both cases, the PGCM reproduces
the energy levels of the even-spin yrast band well. In
the case of the other excited states, the PGCM calculations performed by assuming triaxial deformation
are in good agreement with the shell model results, es+++
pecially for the 2+
2 , 31 , 42 , and 51 states, which are
members of the 𝛾𝛾-band. However, the energy levels
calculated by assuming only axial deformation for the++2+
2 , 31 , and 51 states are higher than those calculatedusing the shell model. Apparently, the description of+++
the 2+
2 , 31 , 42 , and 51 states is not satisfactory whenassuming only axially symmetric shape. The triaxial
components play an essential role in the description ofthese states.
References
1) K.-H. Speidel et al.: Phys. Rev. C 57, 2181 (1998), andreferences therein.
2) G. A. Jones et al.: Phys. Rev. C 76, 054317 (2007).
3) N. Yoshinaga, K. Higashiyama, and P. H. Regan: Phys.
Rev. C 78, 044320 (2008).

Department of Physics, Chiba Institute of Technology
Department of Physics, Saitama University- 49 -

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Simple-model analysis of doublet bands in doubly odd nuclei
N. Yoshinaga∗1 and K. Higashiyama∗2[Nuclear structure, quadrupole coupling model, chopsticks conﬁguration]

E (MeV)

4

106

3

MultipoleRh
Only quadrupole

2

1
QCM
Expt.

0
1

3

5

7

9 11 13 15 17

1

I (h )

3

5

7

9 11 13 15 1730
2

B ( M1 ) B ( E2 ) [( µ N eb ) ]Recently, the study of Δ𝐼𝐼 = 1 doublet bands become one of the most interesting subjects in nuclear
physics. Such pairs of bands arising from the high-𝑗𝑗
orbitals of a neutron and a proton have been experimentally found in many doubly odd nuclei. In order to characterize the doublet bands in a simple andconsistent manner, we developed the quadrupole coupling model (QCM)1–3) , in which the collective core
representing the even-even part of the nucleus couples
with a neutron and a proton in intruder orbitals via
quadrupole-quadrupole interactions.
We applied this model to the doublet bands built
on the 𝜈𝜈𝜈11/2 ⊗ 𝜋𝜋𝜋𝜋9/2 conﬁguration for the doubly odd
nuclei with a mass of approximately 1003) . With thisapproach, the experimental energy levels and electromagnetic ratios 𝐵𝐵(𝑀𝑀 1; 𝐼𝐼 → 𝐼𝐼 − 1)/𝐵𝐵(𝐸𝐸2; 𝐼𝐼 → 𝐼𝐼 − 2)have been successfully reproduced. Analysis of the
wave functions revealed a new band structure, which
resulted from the “chopsticks conﬁguration” of the unpaired neutron in the 0ℎ11/2 orbital and the unpaired
proton in the 0𝑔𝑔9/2 orbital, weakly coupled with thequadrupole collective excitations of the even-even core.
In this study, we extend the QCM to include multipole
interactions for the neutron 0ℎ11/2 orbital and the proton in the 0𝑔𝑔9/2 orbital.
In Fig. 1, the experimental energy levels based onthe 𝜈𝜈𝜈11/2 ⊗ 𝜋𝜋𝜋𝜋9/2 conﬁguration are compared with

Multipole
Only quadrupole
Expt.

20

10

0

10

12

14

I (h)

16

18

Fig. 2. Comparison of 𝐵𝐵(𝑀𝑀 1; 𝐼𝐼 → 𝐼𝐼 − 1)/𝐵𝐵(𝐸𝐸2; 𝐼𝐼 → 𝐼𝐼 − 2)ratios in the QCM with the experimental data (expt.).
Solid and dotted lines show the results obtained when
considering multipole interactions and those obtained
when considering only quadrupole interactions, respectively.

those calculated using the QCM for 106 Rh. The current results obtained by considering the multipole interactions and those obtained by considering only thequadrupole interactions3) are shown in the left andright panels, respectively. In our previous study3) ,we failed to reproduce the bandhead state; experimen−
tally, the 6−
1 state was lower in energy than the 71
state, while theoretical studies indicated that the 6−
1state was higher in energy than the 8−
1 state. In thepresent analysis, however, we succeeded in reproducing
the bandhead energy of the 6−
1 state. Moreover, the−energies of the 10−and10stateswere considerably
1
2
improved.
In Fig. 2, we compare the theoretical ratios
𝐵𝐵(𝑀𝑀 1; 𝐼𝐼 → 𝐼𝐼 −1)/𝐵𝐵(𝐸𝐸2; 𝐼𝐼 → 𝐼𝐼 −2) for the yrast stateswith the experimental values. The theoretical result
gives a successful description of the large-amplitude
staggering of the 𝐵𝐵(𝑀𝑀 1)/𝐵𝐵(𝐸𝐸2) ratios. The mechanism underlying this even-odd staggering has been
discussed in detail within our present model3) . In thepresent study, we also found that while neutron andproton quadrupole interactions are dominant among
other interactions, octupole and hexadecapole interactions are more important for reproducing the bandheadenergies.
References

Fig. 1. Calculated energy levels (crosses) and experimental
data (open circles) as a function of spin 𝐼𝐼 for the stateswith 𝜈𝜈𝜈11/2 ⊗ 𝜋𝜋𝜋𝜋9/2 conﬁguration in 106 Rh.
∗1∗2

Department of Physics, Saitama University
Department of Physics, Chiba Institute of Technology- 50 -

1) N. Yoshinaga and K. Higashiyama: Eur. Phys. J. A 30,
343 (2006); 31, 395 (2007).
2) K. Higashiyama and N. Yoshinaga: Eur. Phys. J. A 33,
355 (2007).
3) K. Higashiyama and N. Yoshinaga: Prog. Theor. Phys.
120, 525 (2008).

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Linear Response Calculation Using
Canonical-basis TDHFB with a Schematic Pairing Functional
S. Ebata,∗ 1 T. Nakatsukasa T. Inakura,∗ 1,∗ 2 Y. Hashimoto,∗ 2 and K. Yabana∗ 1,∗ 2[Nuclear structure, unstable nuclei]
is the gap energy, and εl (t) ≡ ⟨ϕl (t) | ĥ[ρ(t)] | ϕl (t)⟩.
These equations obey the same conservation rules as
do the original CbTDHFB equations1) .
We solve the CbTDHFB equations in real time andcalculate the linear response of the nuclei. In thelinear-response calculation, we consider an externalﬁ eld V̂ext (r, t) which is weak and instantaneous in time,V̂ext (r, t) ≡ −k F̂ δ(t); k ≪ 1. F̂ is a one-body operator, for example, the isoscalar quadrupole operator,
Q̂20 = r2 Y20 . We calculate the time evolution of the
expectation value of F̂ and obtain the strength function S(F̂ ; E) by Fourier transformation1) .
Figure 1 shows the isoscalar quadrupole strength
functions (K = 0) for magnesium isotopes, calculatedusing the SkM∗ parameter set. In this calculation, theground states of these isotopes are found to be deformed into a prolate. These calculations employ aschematic pairing functional and a very good approximation of the HFB+QRPA using a realistic paring
functional.
Currently, we are developing a CbTDHFB codefor parallel computing to facilitate the calculation forheavy nuclei. With this new code, we plan to carryout a systematic investigation of nuclear responses.
S(E;Q20) [fm4/MeV]

80

� 2

36

Mg

20

25

40

Mg

20

25

Mg

40
20

and
where ρl ≡ |vl |2 are the occupation probabilities,∑
Kl ≡ ul vl are the pair densities; ∆ ≡ G̃ l>0 f (ε̄l )Kl (t)

� 1

34

60

Graduate School of Pure and Applied Sciences, Universityof Tsukuba
Center for Computational Science, University of Tsukuba- 51 -

0

0

5

80

S(E;Q20) [fm4/MeV]The recent progress at radioactive facilities such as
RIBF in RIKEN has resulted in a strong demand fortheoretical frameworks that can analyze and predictthe properties of unknown nuclei. Such a, frameworks
should include the eﬀ ects of nuclear deformation andpairing correlation, and should be capable of calculating properties of not only the ground state but also
the excited state. A combination of the Hartree-FockBogoliubov method and quasiparticle-random-phaseapproximation (HFB+QRPA) is a candidate for such aframework, and it is applicable to a wide range of lightand heavy nuclei. However, in this framework, considerable eﬀ orts are required for coding the programs,
and signiﬁ cant computational resources are necessary.
The HFB+QRPA for deformed nuclei is currently stillin the preliminary stage.
We proposed the canonical-basis time-dependent
Hartree-Fock-Bogoliubov (CbTDHFB) in the threedimensional coordinate-space representation, which
can take into account the eﬀ ect of nuclear deformation without symmetry-restriction while treating thepairing correlation in the BCS-like approximation. We
reported in brief the derivation and conservation rulesof the CbTDHFB equations1) .
We derived the CbTDHFB equations using the timedependent variational principle; they can be achieved
only ∑
if we choose a special pairing functional Epair =−G| l>0 ul (t)vl (t)|2 . Here, ul and vl correspond to
the time-dependent BCS factors for the canonical pairof states ϕl (r, t) and ϕl̄ (r, t). Note that the state l̄ is
not necessarily the time-reversed state of the state l.
This year, we∑ use the modiﬁ ed pairing functional,′
Epair= −G̃| l>0 f (ε̄l )ul (t)vl (t)|2 , to treat a wide
range of nuclei. Here, f (ε) is a cut-oﬀ function, and ε̄lare the single-particle energies of the ground state. In
the present calculation, f (ε̄l ) are ﬁ xed during the time
evolution. The parameter G̃ and the function f (ε) are
the same as those given in Ref.2) When we choose the′pairing functional Epair, the CbTDHFB equations are
written as()
 ih̄ϕ̇l (r, t) = ĥ[ρ(t)] − εl (t) ϕl (r, t),ih̄ρ̇l (t) = f (ε̄l )(∆∗ (t)Kl (t) − ∆(t)Kl∗ (t)),
ih̄K̇l (t) = Kl (t)(εl (t) + εl̄ (t)) + f (ε̄l )∆(t)(2ρl (t) − 1),

10

15

20

25

Energy [ MeV ]

30 0

5

10

15

Energy [ MeV ]

38

Mg

60

30

40
20
0

0

5

10

15

20

Energy [ MeV ]

25

30 0

5

10

15

Energy [ MeV ]30

Fig. 1. The quadrupole strength functions (K = 0) for
34,36,38,40
Mg calculated using the Skyrme functional of
the SkM� parameter set. The smoothing parameterΓ = 2 MeV is used.

References
1) S. Ebata et al.: RIKEN Accel. Prog. Rep. 42, 49 (2009).
2) N. Tajima et al.: Nucl. Phys. A 603, 23 (1996).

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Finite Amplitude Method for QRPA
P. Avogadro, T. Nakatsukasa
The aim of this research is to generalize the finite
amplitude method (FAM)1) for the purpose of making it applicable to superfluid systems. In practice we
aim to develop a quasiparticle random phase approximation (QRPA) code from a Hartree Fock Bogoliubov(HFB) code. The QRPA formalism can be used to determine the structure and energy of low-lying excitedstates of nuclei in which pairing correlations play animportant role; thus, the formalism is useful for the
study of exotic nuclei. Generally it is difficult to use
this formalism because of two main reasons. The firstreason is that the “construction” of the QRPA matrix is difficult; the analytic derivation of the nuclear
Hamiltonian in some cases (especially in deformed systems) is extremely complicated, and some parts of the
Hamiltonian have to be neglected, leading to a lossof full self-consistency. The second reason is that the
QRPA matrix is usually large, and hence, the diagonalization procedure is time consuming. The FAM helps
to overcome the first difficulty. The QRPA equationsin the standard formulation are as follows:





X
X
A B
=
ω
.
(1)
Y
−Y
B ∗ A∗

These equations are equivalent to the TDHFB equations in the small-amplitude limit2) ; in order to prove
this equivalence we write the quasiparticle annihilation
operator as the sum of the HFB operator and a timedependent-perturbation:aµ (t) = (aµ + δaµ (t)) e−iEµ t .

(2)

By substituting Eq. (2) in the quasiparticle annihilation operator equation of motion and by expressing the
TDHFB Hamiltonian as the sum of the HFB Hamiltonian term and a small perturbation, we obtain:i∂δa(t)= Eµ δaµ (t)+[HHF B , δaµ (t)]+[δH(t), aµ ] .(3)∂t

By Fourier expansion, we obtain a set of equations thatis equivalent to Eq. (1):A(ω) = ωXνµ(Eµ + Eν )Xνµ + δHµν
,
(4)
∗
A†
∗
 νµ (ω) = −ωYνµ(Eµ + Eν )Yνµ + δ H

where Eν and Eµ represent the quasiparticle energies,†and δH A and δH A are defined as follows: ∗ (ω)V ∗δH A (ω) = U † δh(ω)V ∗ − V † δ ∆
†
∗
†
T ∗
+U δ∆(ω)U − V δh U ,δH A† (ω) = U † δh† (ω)V ∗ − V † δ∆∗ (ω)V ∗∗
+U † δ ∆(ω)U− V † δh∗ U ∗ .

(5)obtained from HFB calculation. In general, the calculation of the matrix elements of Eq. (4) is not easierthan Eq. (1). The FAM facilitates the calculation of
Eq. (5) and Eq. (6), which are the terms of Eq. (4)that are difficult to calculate. In order to understandthe FAM clearly, we emphasize that in the TDHFB
approximation, self-consistency is maintained always.
When a nucleus is excited, density perturbations withrespect to the ground state (i.e. the HFB state) arepresent. In the small-amplitude limit, the fields (h and∆) can be expanded linearly as functions of the densities: δh = δh(δρ) and δ∆ = δ∆(δκ), on the other
hand, the transition densities in the QRPA formalism
are functions of the X and Y amplitudes thus the residual fields can be written as follows: δh = δh(X, Y )and δ∆ = δ∆(X, Y ). In practice, δh(ω) and δ∆(ω)
are calculated using numerical derivatives; in the casein which the pairing interaction depends only on theabnormal density, FAM gives:
δh(ω) =

h[(V ∗ + ηU X)(V T + ηY T U † ) − h[ρ0 ]],ηδh† (ω) =h[(V ∗ + ηU Y ∗ )(V T + ηX † U † ) − h[ρ0 ]],ηδ∆(ω) =∆[(V ∗ + ηU X )(U T + ηY T V † ) − ∆[ρ0 ]],ηδ ∆(ω)=∆[(V ∗ + ηU Y ∗ )(U T + ηX † V † ) − ∆[ρ0 ]].
η

The small parameter η has been introduced for numerical differentiation. The FAM procedure needs the X
and Y QRPA amplitudes; however these quantities are
the solutions that we aim to obtain. Hence we carryout iterative procedures such as the conjugate gradientmethod. The algorithm starts with a guess for the solution (X and Y in this case) and returns a new valuethat is closer to the exact solution; the process canthen be repeated till convergence is attained. A QRPA
code obtained by the FAM is fully self-consistent. All
the terms in the single-particle Hamiltonian present
in the original HFB code are automatically taken into
account through numerical derivatives; moreover, theapplication of the FAM is not restricted to systems
with spherical symmetry. This technique can thus bea very useful tool to obtain a fully self-consistent deformed QRPA code.
References(6)Here, U and V represent the quasiparticle amplitudes- 52 -

1) T. Nakatsukasa, T. Inakura and K. Yabana: Phys. Rev.
C 76, 024318 (2007)
2) P. Ring and P. Shuck: The Nuclear Many Body Problem,
Springer-Verlag, Berlin (1980).

1

!, µ (MeV)RIKEN Accel. Prog. Rep. 43 (2010)

1.4
1.2
1.0
0.8
0.6
0.4
0.2
0.0
-0.2

BCS
MBCS
LN
LNSCQRPA

thin !
thick µ0- 53 -1

2
T (MeV)

3

RIKEN Accel. Prog. Rep. 43 (2010)

Canonical ensemble treatments of pairing in ﬁnite systems
N. Quang Hung and N. Dinh Danga)This is true only for nonzero T because one has to construct
the partition function with all excited states.

- 54 -Ω = N = 10
Ω = N = 10(a)(a)

1.2(MeV)∆∆(MeV)∆ (MeV)

54
3
2
1

pf+sdg Shell

(d)
(d)

0.4
0.4

30 30

E (MeV)E (MeV)

20 20
10 10

(b)(b)

20 20
15
15
10
10
5
5
0

56

56 Fe
Fe Shell
pf+sdg

1.2

0.8
0.8

E (MeV)

1

1

2

3

2 T 3(MeV)4T (MeV)

-95
-95
(e)
(e)

-105
-105

(c)(c)

0

-85
-85

20
20
15
15
10
10
5
50
0

(f )

(f )

CC

E (MeV)

5
4
3
2
1

C

C

As the atomic nucleus is a system with a ﬁxed number of particles, the thermodynamic averages of the exact solutions of the pairing problem are usually carriedout within the canonical ensemble (CE), and the results are compared with theoretical predictions, which
are however obtained within the grand canonical ensemble (GCE). The latter consists of identical systems
in thermal equilibrium, each of them exchanges its energy and particle number with an external reservoir.
The systems of the CE exchange only their energy,
whereas the particle number is ﬁxed, remaining thesame for all systems. Moreover, although the pairing
problem can be solved exactly, the exact diagonalization of the pairing Hamiltonian is impracticable forlarge particle numbers (N >14) in the case of halfﬁlled model N = Ω (Ω is number of single-particle levels) a) . It is therefore highly desirable to construct anapproach based on the CE, which can oﬀers results ingood agreement with the exact CE ones for any valueof the particle number. Such approach is proposed in
the present study.
The main idea of present study is to embed thesolutions of the pairing Hamiltonian obtained within
the BCS and selfconsistent quasiparticle RPA (SCQRPA)1) combined with the Lipkin-Nogami particlenumber projection for each total seniority or numberof unpair particles S = 0, 2, ..., Ω at zero temperature
into the CE. These approaches are called the CE-BCS
and CE-SCQRPA, respectively, whereas the GCE-BCS
stands for the conventional ﬁnite-temperature BCS. In
this way, the number of eigenstates and computationaltime are much reduced within the present approaches.
The proposed approaches are tested within a schematic
model as well as for a realistic nucleus. For theschematic model, we employ the doubly-degenerated
multilevel pairing model whose single-particle energy
are chosen as ϵj = 0, 1, ..., Ω − 1. The model is halfﬁlled, i.e. N = Ω. As for the realistic nucleus, we employ the same Woods-Saxon single-particle spectrum
from Table I of Ref2) for neutron in pf + sdg shellof 56 Fe so that we can compare the results obtained
within our approaches with the predictions by theﬁnite-temperature quantum Monte-Carlo (FTQMC)
method2) . The analysis of numerical calculations forthe total energy E, pairing gap ∆ and heat capacity
C shows that the CE-SCQRPA oﬀers the best ﬁts tothe exact results as well as those obtained within the
FTQMC calculations (See e.g. Fig. 1). The CE-BCS∆ (MeV)[NUCLEAR STRUCTURE, pairing, canonical ensemble, BCS theory, quasiparticle RPA.]

4

5

5

0

0

1

2

3

1 T (MeV)
23
T (MeV)

4

4

Fig. 1. Pairing gaps ∆, total energies E and heat capacities C as function of temperature T (MeV) obtainedfor N = 10 (left panels) with interaction parameter
G =1 MeV and for neutrons in 56 Fe with G=16/A MeV(A=56). The thin dashed, thick dashed, and thick lines
denote the results obtained within the GCE-BCS, CEBCS and CE-SCQRPA, respectively. The thin lines in
the left panels stand for the exact CE, whereas those in
the right panels depict the FTQMC calculations.

results are a little bit oﬀ from the exact ones but still
oﬀer much better agreement with the exact solutions
than the predictions by the GCE-BCS. The most interesting feature here is that neither the pairing gaps
obtained within the CE-BCS nor those obtained within
the CE-SCQRPA collapse at a critical temperature TC
as predicted by the GCE-BCS, but they monotonously
decrease with increasing T [See e.g. Fig. 1 (a) and (d)].
As the result, the superﬂuid-normal phase transitionis smoothed out even within the CE-BCS calculations
due to the eﬀects of quantal and thermal ﬂuctuations.
This feature suggests that any exact particle-number
projection method at ﬁnite temperature, which could
bring a GCE-BCS to CE-BCS, should have the samefeature as presented here with a nonvanishing gap.
Since present approaches do not involve any matrix
diagonalization, its merit resides in its simplicity andits application to larger ﬁnite systems, where the exact
solution is impracticable, whereas the FTQMC is time
consuming.
References
1) N.Q. Hung and N.D. Dang: Phys. Rev. C 76, 054302(2007).
2) S. Rombouts, K. Heyde, and N. Jachowicz: Phys. Rev.
C 58, 3295 (1998).

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Top-on-top mechanism for TSD bands in even mass nuclei†
K. Tanabe,∗1,∗2 and K. Sugawara-Tanabe∗1,∗3[TSD bands, Particle-rotor model, D2 -invariance]
The algebraic solution to the particle-rotor modelwith high j nucleon coupled to a triaxially deformed
core, H = Hrot + Hsp .1,2) , successfully takes into account the Coriolis term, I · j, which mediates strong
correlation between two tops, i.e., the rotating core
 = I − j and the single-particle top with j.
with R
This makes a big difference from the wobbling model.3)
We have demonstrated that such a “top-on-top mechanism” not only reproduces the energy level scheme,1)
but also gives the approximate selection rules for theE2 and M 1 transitions among TSD bands2) in the
odd mass Lu isotopes. The TSD bands are classified
in terms of two quantum numbers, (nα , nβ ), describing the precession of total angular momentum I and of
the single-particle angular momentum j, respectively.
Invariance of the nuclear states under D2 symmetry restricts the range of nα and nβ depending on I − j. We
have estimated the overlap, GIj
na nb ;nα nβ , between the
eigenstates of H expressed by boson numbers nα andnβ , and the original Holstein-Primakoff boson numbers
na and nb .
In extending the above scheme to the TSD bands ineven-even nuclei, the angular momentum j is assumed
to be a sum of two single particle angular momenta
as j = j1 + j2 , and the magnitude of integer j is kept
as a constant over a certain range of I. Then, the3transition rates gain a factor of G0000 G1010 ∝ ( I−jI )both for E2- and M1-transitions with ∆I = 1 among
the favored (0,0) and the unfavored (1,0) bands. The
value of I − j is smaller for even-A case than odd-A
case, which makes the observation of the other partnerband in even mass nuclei difficult. This explains thesituation that no linking transition between the (0,0)
and the (1,0) bands has been found for the TSD bandsin Hf isotopes and 164 Lu.
References
1) K. Tanabe and K. Sugawara-Tanabe: Phys. Rev. C 73,
034305 (2006); ibid. 75, 059903(E) (2007).
2) K. Tanabe and K. Sugawara-Tanabe: Phys. Rev. C 77,
064318 (2008).
3) A. Bohr and B. R. Mottelson: Nuclear Structure (Benjamin, Reading, MA,1975), Vol. II.

†
∗1
∗2
∗3

Based on the article in Bull. Am. Phys. Soc. 54, No. 10, 69(2009)
Theoretical Nuclear Physics Laboratory, RIKEN Nishina
Center, Wako, Saitama 351-0198
Department of Physics, Saitama University, Sakura-Ku,
Saitama 338-8570
Otsuma Women’s University, Tama, Tokyo 206-8540- 55 -

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

SU(3) symmetry in anisotropic harmonic oscillator†
K. Sugawara-Tanabe,∗1,∗2 K. Tanabe,∗1,∗3 A. Arima,∗4 and B. Gruber∗5[Triaxially deformed harmonic oscillator, SU(3) invariance, New magic numbers]
In this paper we propose a new boson transformation by which all the oscillator states for an anisotropic
case can be embedded in the SU(3) bases.1) We startfrom an anisotropic harmonic oscillator Hamiltonian
without spin-orbit interaction, whose oscillator frequencies ωx , ωy and ωz are related to the deformation parameters β and γ. Suppose that three oscillator frequencies have an integral rational ratio a :b : c, i.e., ωx = aωsh , ωy = bωsh and ωz = cωsh .
Then, the eigenvalues and eigenfunctions of H are
described by a set of quantum numbers (nx , ny , nz ),)|nx , ny , nz . Here
H|nx , ny , nz  = h̄ωsh (Nsh + a+b+c
2
the nk is the eigenvalue of the number operator n̂k =c†k ck , with the harmonic oscillator boson operator ck(k = x, y, z), and Nsh = anx + bny + cnz . In orderto rewrite H in a SU (3)-invariant form, we expressck (k = x, y, z) in terms of an m-fold product of new
bosons sm (m = a, b, c), by requiring s†m sm = mc†k ck ,and [sm , s†m ] = 1. The new bosons sm are introduced
for any positive integer m by the non-linear transfor 
−1/2
m−1
(sm )m =mation, i.e. ck = m r=1 (n̂m + r)
1/2
Γ(n̂m +1)(sm )m , where n̂m = s†m sm . Thus,mΓ(n̂m +m)
we have N̂sh = s†a sa + s†b sb + s†c sc . In dealing withmany
boson states, the projection operator, Pm =
m−1
1
i 2πk
m n̂m
(m = a, b, c), may be useful tok=0 emeliminate unphysical states other than the eigenstatesof the original Hamiltonian. We can classify the singleparticle states in terms of three quantum numbers, i.e.,
two diagonal operators expressed by number operators
together with a Casimir operator. The single-particle
level given by Nsh provides new magic numbers for thecase of triaxially deformed harmonic oscillator.
References
1) K. Sugawara-Tanabe, K. Tanabe, A. Arima and B. Gruber: Phys. Rev. C 80, 044307 (2009).

†
∗1
∗2
∗3
∗4
∗5

Condensed from the article in Phys. Rev. C 80, 044307(2009)
Theoretical Nuclear Physics Laboratory, RIKEN Nishina
Center, Wako, Saitama 351-0198
Otsuma Women’s University, Tama, Tokyo 206-8540
Department of Physics, Saitama University, Sakura-Ku,
Saitama 338-8570
Science Museum, Japan Science Foundation, Tokyo 1020091
College of Science, Southern Illinois University, Carbondale,
Illinois 62901, USA- 56 -

1

RIKEN Accel. Prog. Rep. 43 (2010)- 57 -

RIKEN Accel. Prog. Rep. 43 (2010)- 58 -

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Mass-number dependence of total reaction cross sections in theblack-sphere approximation
A. Kohama, K. Iida,∗1 and K. Oyamatsu∗2[Nuclear reaction, reaction cross section, nuclear radius]
Neutron-rich unstable nuclei often exhibit exotic
properties, such as “unexpectedly” large interaction
cross sections. In order to quantify these properties,
we have to pay attention to the deviation from, for example, total reaction cross sections that are carefully
calculated on the basis of our sound knowledge of stable
nuclei. Systematic understanding of the mass-number(A) and energy dependence is indispensable for clarifying the non-exotic behavior of the cross sections.
Recently, we have developed a formula for a protonnucleus total reaction cross section σR as a function of
the mass and the neutron excess of the target nucleus
and the proton incident energy Tp in a way free fromany adjustable Tp -dependent parameters.1) We deducethe dependence of σR on Tp on the basis of the nuclear“optical” depth to the projectile within the frameworkof a black-sphere (BS) approximation of nuclei. We
call the formula the BS cross-section formula. The
scale of the formula is set by the BS radius a, which
is determined by fitting the angle of the first elastic
diffraction peak calculated for proton diffraction by acircular black disk of radius a to the measured value.2)
The energy dependence of the formula is driven bythat of proton-nucleon total cross sections. For stable nuclei, this formula reproduces the empirical Tp
dependence of σR at Tp = 100–1000 MeV remarkably
without requiring any adjustable Tp -dependent parameters. Due to its suitability in systematic calculations,the present formula is being incorporated into the Particle and Heavy Ion Transport code System (PHITS).
In this work, we examine the A-dependence of the
BS cross-section formula. We analytically find that
our formula includes A1/6 -dependence in addition to
A2/3 -dependence. The former dependence, which isdue to the optical depth, is one of the characteristicfeatures of our formula. In Fig. 1, we compare ournumerical results with those obtained by the Carlson
formula,3) which is an example of a formula based ongeometrical arguments and is given by σR = π(Rp +r0 A1/3 )2 , where Rp and r0 are parameters obtained byfitting to the empirical data.3) The difference between
the two is remarkable in the energy range between 100
MeV and 600 MeV, but it is still unclear whether or not
such a difference is due to the different A-dependenceof each formula. Further work is currently in progress.

∗1∗2

Department of Natural Science, Kochi University
Department of Library and Information Science, Faculty of
Letters, Aichi Shukutoku University- 59 -

Fig. 1. Comparison of the numerical results of σR (p +natu.
C) (upper) and σR (p + Pb) (lower) obtained by
the BS cross-section formula (solid curve) with thoseby the Carlson formula ( on dashed line). We adopt
the BS radii at 800 MeV as 2.7 fm for carbon and 5.7 fm
for lead. We also plot the empirical data, which were
presented by Carlson (◦)3) and by Auce et al. (×).4)
σBS (≡ πa2 ), which is represented by squares with cross,is consistent with measured σR .

References
1) K. Iida et al.: J. Phys. Soc. Japan 76, 044201 (2007).
2) A. Kohama et al.: Phys. Rev. C 72, 024602 (2005).
3) R.F. Carlson: At. Data Nucl. Data Tables 63, 93 (1996).
4) A. Auce et al.: Phys. Rev. C 71, 064606 (2005).

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Holographic Nuclei†
K. Hashimoto∗1[Giant resonances, Superstring theory, AdS/CFT correspondence]
We provide a dual gravity description of heavy
atomic nuclei, via AdS/CFT correspondence. In holographic QCD such as Sakai-Sugimoto model, baryons
are D-branes wrapping a sphere in 10 dimensional
curved spacetime, so any nucleus is a collection of A
such D-branes where A is mass number of the nucleus.
Quantum theory on the nucleus is ADHM-like U (A)Yang-Mills-Higgs theory on the sphere. Taking a large
A limit (corresponding to heavy nuclei) leads to a dual
gravity describing collective excitataions of constituent
nucleons of the heavy nucleus. This dual gravity computes spectra of the heavy nucleus, and gives discrete
states whose gap roughly agrees with experimental nuclear data.
Application of a superstring technique, the AdS/CFT
correspondence1) , to low energy QCD has provided
quite remarkable progress on hadron physics. Thissubject called holographic QCD has grown up to bea major research arena of string theory. Dual gravity
description has revealed various aspects of low energy
QCD which were unreachable by conventional analytic
methods because of notorious strong coupling. They
include spectra of glueballs, mesons and baryons, andinteractions among them, and even phase transitions
at ﬁnite temperature/density. However, almost all of
the results are on hadron physics, not really nuclear
physics, dare to mention. In this paper, we take a ﬁrst
step toward nuclear physics: we provide a dual gravity
description of heavy nuclei.
The essence of the gauge/gravity correspondence isthe large N limit, where N refers to the rank of thegauge group U (N ) of the gauge theory living on N
coincident D-branes. This limit, together with large
λ (’tHooft coupling) limit, allows a dual, holographic,
equivalent gravity theory on a near horizon geometryof black brane solutions created by the N D-branes.
Baryons in QCD-like gauge theories are described, inthe dual gravity description, by in fact additionally put
D-branes wrapping a higher dimensional sphere in 10
dimensional curved spacetime. Any nucleus is a collection of baryons (nucleons), so in holographic QCD thenucleus is a collection of D-branes. Therefore, heavy
nuclei with large mass number A can have a dual gravity description provided by a near horizon geometry of
those “baryonic” A D-branes, in large A limit. In thispaper we pursue and realize this idea. We describe apossible dual geometry, check its validity as a limit ofstring theory, and provide a comparison with nuclear†∗1

Condensed from the article in Prog. Theor. Phys. 121 (2009)
241
Theoretical Physics Laboratory, RIKEN- 60 -data.
For the D-brane conﬁguration for the baryons in
QCD at strong coupling, we use the D4-D8 model2) .
We distribute the baryonic D4-branes into the shapeof a ball to mimic the spherical nucleus. The nuclear
saturation property is assumed. Then we calculate
the near-horizon back-reacted geometry of these D4branes, and compute ﬂuctuation spectrum of scalarﬁeld in the background. It is ﬁnally given by
En ∼

N 2/3
√ MKK nA1/3 λ(n = 1, 2, · · ·)(1)

We ignored all the numerical factors. This (1) is theexcitation spectrum of heavy nuclei with mass number A, as a result of AdS/CFT correspondence.√ The
coeﬃcient is naively evaluated as N 2/3 MKK / λ ∼O(102 )[MeV], but this is just for order of magnitude.
It is surprising that this formula is actually consistent with the experimental data of heavy nuclei, as
follows. It is known from experiments that heavy nuclei have coherent excitations (phonons) of constituent
nucleons, called giant resonances,a) En = ω(A)n, (n =1, 2, · · ·). Excitations with lower n have been analysed
in detail experimentally. Phenomenological models, including liquid drop model of heavy nuclei, indicatesconsistent harmonic behaviour in n. Experimental results for giant resonance of heavy nuclei with A > 60
shows an empirical formula, E ∼ 80A−1/3 [MeV], forthe ﬁrst gap of 0+ isoscalar excitation. Our result (1)is not so much diﬀerent from the nuclear data, andin particular, we reproduced the A dependence of theresonance excitations.
In this paper, we have given a dual gravity description of heavy atomic nuclei, by applying thegauge/string duality (AdS/CFT correspondence). We
took a large mass number limit A → ∞. Dual gravity description is valid in this limit, and we obtained
a near horizon geometry corresponding to the heavy
nucleus. The corresponding supergravity solution has
discrete ﬂuctuation spectra, and we compared themwith nuclear experimental data.
References
1) J. M. Maldacena, Adv. Theor. Math. Phys. 2, 231(1998).
2) T. Sakai and S. Sugimoto, Prog. Theor. Phys. 113, 843(2005), Prog. Theor. Phys. 114, 1083 (2005).
a)

The author is indebted to T. Nakatsukasa for invaluable
discussions on this correspondence, and also to T. Matsuifor his helpul explanations.

1

RIKEN Accel. Prog. Rep. 43 (2010)

Critical velocity of superﬂuid ﬂow throughsingle barrier and periodic potentials†
G. Watanabe,∗1,∗2,∗3 F. Dalfovo,∗3 F. Piazza,∗3 L. P. Pitaevskii∗3,∗4 , and S. Stringari∗2

†
∗1
∗2
∗3
∗4

Condensed from Ref.1) . This work is also selected for the
Virtual Journal of Atomic Quantum Fluids, 1 (2009).
RIKEN
Asia Paciﬁc Center for Theoretical Physics (APCTP)
CNR INFM-BEC and Department of Physics, University ofTrentoKapitza Institute for Physical Problems- 61 -

1

vc / cs(0)

0.8
0.6
0.4
0.2
0

0

0.2

0.4

0.6 0.8
1
Vmax/µj=0

1

1.2

1.4

LkF = 0.497

0.8vc / cs(0)Ultracold gases in optical lattices provide a new exciting frontier of research. In a recent experimentwith Fermi superﬂuids in one-dimensional (1D) optical lattices, the critical velocity along the BCS-BEC
crossover has been measured and the result of this measurement has revealed that superﬂuidity is particularlyrobust at unitarity2) . The critical velocity of superﬂuid
ﬂow is a fundamental issue in the physics of quantum
ﬂuids. A mechanism for the onset of dissipation is provided by Landau instability: if the excitation spectrum
satisﬁes suitable criteria, there exists a critical ﬂow velocity above which the kinetic energy of the superﬂuid
can be dissipated via the creation of excitations.
Motivated by the above experiment, we study the
problem of an ultracold atomic gas in the superﬂuid
phase ﬂowing in the presence of a potential barrier or aperiodic potential1,4) . Using a a hydrodynamic scheme
in the local density approximation (LDA), we obtainan analytic expression for the critical current jc as afunction of the barrier height or the lattice intensity,
which applies to both Bose and Fermi superﬂuids1) .
We compare this prediction with the results of the numerical solutions of the Gross-Pitaevskii (GP)1) and
Bogoliubov-de Gennes (BdG) equations1,3) .
In Fig. 1, we show the critical velocity vc in thecase of the single rectangular barrier (top panel) andthe periodic potential (bottom panel). In both cases,
one clearly sees that the results of the BdG equations approach the LDA prediction when the widthof the barrier (the half of the lattice spacing) L ismuch larger than the healing length ξ ∼ 1/kF , wherekF = (3π 2 n)1/3 is the Fermi momentum of a uniform
non-interacting Fermi gas of density n. The way of approach is, however, diﬀerent. In the case of the periodic
potential, vc exhibits a plateau for LkF � 1 and small
maximum Vmax of the external potential; the plateau
is instead absent in the case of the single barrier.
Our results allow one to identify three limiting cases:i) a regime of hydrodynamic ﬂow in the LDA (close to
the thick solid lines in Fig. 1); ii) a regime of macroscopic ﬂow through thin and weak barriers, where
the LDA is not applicable, i.e., for LkF � 1 andVmax /µ < 1; iii) a regime of weakly coupled superﬂuids separated by thin and strong barriers, i.e., for
LkF � 1 but Vmax /µ � 1.

LkF = 1.11

0.6

LkF = 0.886

LkF = 1.57

0.4
0.2
0

LkF = 1.92
LkF = 2.48

0

0.5

1

1.5
2
Vmax / µj=0

2.5

3Fig. 1. Critical velocity for energetic instability of a superﬂuid of dilute fermions at unitarity subject to a 1D
external potential. The critical velocity vc is given in(0)units of the sound velocity of a uniform gas, cs , andis plotted as a function of the maximum of the external potential in units of the chemical potential µj=0 of
the superﬂuid at rest. Top panel: the case of a single
potential barrier. Bottom panel: the case of a periodic
potential. Thick solid lines: prediction of the LDA hydrodynamic theory. Symbols in the top panel: BdG
results of Ref.3) with LkF = 4. Symbols in the bottom
panel represent our BdG results for a periodic lattice.
The thinner black solid lines are the tight-binding prediction. Dashed lines are guides to the eye. This ﬁgure
is taken from Ref.1) .

We ﬁnally discuss the relevance of these results in thecontext of current experiments with ultracold gases.
References
1) G. Watanabe et al., Phys. Rev. A 80, 053602 (2009).
2) D. E. Miller et al., Phys. Rev. Lett. 99, 070402 (2007).
3) A. Spuntarelli, P. Pieri, and G. C. Strinati, Phys. Rev.
Lett. 99, 040401 (2007).
4) G. Watanabe et al., Phys. Rev. A 78, 063619 (2008).

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Contribution of Nuclear Reaction Data Centre to RIKEN Nishina
CenterK. Kato,∗1 M. Kimura,∗2 N. Otuka,∗3 T. Asano,∗4 N. Furutachi,∗4 A. Makinaga,∗4 T. Matsumoto,∗4
T. Togashi,∗1 and K. Tsubakihara∗4[Nuclear reaction, database, NRDF, EXFOR]The development of a nuclear reaction database isvery important not only in nuclear physics but also inastrophysics and nuclear power engineering. The “Nuclear Reaction Data Centre” (JCPRG) was establishedon April 1, 2007, for compiling own nuclear database,
NRDF. The center was approved as a branch of Facultyof Science at Hokkaido University, and it took over nuclear database activities carried out by Japan ChargedParticle Nuclear Reaction Data Group. Furthermore,another important task of the center as a member ofInternational Network of Nuclear Reaction Data Centers is to cooperate on EXFOR nuclear database compilation . The members of JCPRG have been devoting
themselves to the following activities:(1) Compilation of reaction data (NRDF and Experimental Nuclear Reaction Data, EXFOR)(2) Development of a new nuclear reaction databasefor astrophysical evaluation (NRDF/A)(3) Conversion of old data from NRDF format to
EXFOR format(4) Bibliography compilation (CINDA)(5) Database maintenance and development (NRDF,
EXFOR/ENDF, and CINDA)(6) Development of a digitization system (GSYS).
In particular, we adopt a strategy where the reaction
data obtained from domestic institutes is compiled ina domestic nuclear database, since frequent communication with authors will be helpful for quickly and precisely compiling the given reaction data. For this purpose, we have been compiling the experimental dataobtained from Japanese facilities. These results canbe accessed through our web site1) .
In Table 1, we list the number of papers that were selected for compilation in NRDF and for conversion into
the EXFOR format in 2009. We also list the number ofcompiled papers in which the reaction data obtained
from RIKEN facilities were used. This tables showsthat the papers reporting RIKEN experiments2–12) appear to constitute a majority of NRDF entries and theentries converted to the EXFOR format. These data
can be accessed in the EXFOR database13) with the
∗1
∗2
∗3
∗4

Department of Physics, Faculty of Science, Hokkaido University
Creative Research Institution, Sosei Research Department,
Hokkaido University
IAEA Nuclear Data Section
Nuclear Reaction Data Centre (JCPRG), Faculty of Science,
Hokkaido University- 62 -

E-numbers shown in the References.
In addition to cooperating with IAEA-NDS, we haveto provide domestic experimental data to the international nuclear physics community with easy access, inthe form of original tasks of NRDF. Recently, the center established a research contract with the RIKEN
Nishina Center in order to compile eﬃciently the reaction data obtained by using beams of unstable nuclei
at the RIKEN Nishina Center, RIBF. We are now discussing the extension of the NRDF format in order tocompile new experimental data that will be obtained
from RIBF. In the future, in cooperation with experimentalists, it will be important to develop the domestic database, NRDF, to compile all data obtained fromRIKEN and other Japanese institutes.
Table 1. The number of papers chosen for compilation in
NRDF and for conversion from the NRDF format tothe EXFOR format in 2009. All entries are obtained
from the papers published in 2008 and 2009.

NRDF entries
Entries converted to EXFOR

RIKEN
17
11

Total
51
32

References
1) http://www.jcprg.org/
2) J. J. He et al.: Eur. Phys. J. A 36, 1 (2008); E2107 in
EXFOR.
3) T. Ohnishi et al.: J. Phys. Soc. Jpn. 77, 083201 (2008);
E2116 in EXFOR.
4) S. Ota et al.: Phys. Lett. B 666, 311 (2008); E2120 in
EXFOR.
5) H. Iwasaki et al.: Phys. Rev. C 78, 021304(R) (2008);
E2122 in EXFOR.
6) A. Ozawa et al.: Phys. Rev. C 78, 054313 (2008); E2124
in EXFOR.
7) M. Janek et al.: Phys. of At. Nucl. 71, 1495 (2008);
E2125 in EXFOR.
8) J. Gibelin et al.: Phys. Rev. Lett. 101, 212503 (2008);
E2127 in EXFOR.
9) Y. Kondo et al.: Phys. Rev. C 79, 014602 (2009); E2132
in EXFOR.
10) H.Yamaguchi et al.: Phys. Lett. B 672, 230 (2009);
E2133 in EXFOR.
11) D. Kaji et al.: J. Phys. Soc. Jpn. 78, 035003 (2009);
E2137 in EXFOR.
12) T. Nakamura et al.: Phys. Rev. C 79, 035805 (2009);
E2139 in EXFOR.
13) http://www.jcprg.org/exfor/1

3.

Hadron Physics

RIKEN Accel. Prog. Rep. 43 (2010)

Gluon-Spin Contribution to the Proton Spin from the
Double-Helicity Asymmetry in Inclusive π 0 Production in Polarized√
p + p Collisions at s = 200 GeV†
K. Boyle∗1 and S. Taneja∗2 for the PHENIX Collaboration[Gluon Spin, Helicity Asymmetry, PHENIX]

where N++(+−) is the yield in the same (opposite) helicity collisions, L is the luminosity, R is√the relative luminosity and P is the polarization. At s = 200 GeV,
we sample the gluon momentum fraction range of0.02 < x < 0.3, and so we write ∆G[0.02,0.3] .
Results for ALL in π 0 production in the 20051) and2006 RHIC runs are plotted as a function of transverse
momentum, pT in Fig. 1a. The systematic uncertainty(not shown) in ALL from the relative luminosity determination is 5 × 10−4 in the combined result. A scaling
uncertainties from polarization of 6.8% is not shown.
The data are plotted along with expectations based on
different fits to the DIS data.
The different fits to DIS have significantly distinct
shapes as a function of x. By varying the size of thegluon polarization in the different DIS fit results, a
set of ALL expectations for each fit is produced. χ2 iscalculated for different values of ∆G and the results areplotted in Figure 1b. At ∆χ2 = 9 (∼ 3σ), a consistentconstraint of −0.7 < ∆G[0.02,0.3] < 0.5 is found.
Using one fit to the DIS data, GRSV3) , the impact of
the systematic uncertainties are shown in Fig. 2 when
the polarization and relative luminosity uncertainties
are varied by ±1σ. It is clear that while the polarization uncertainty has little effect, there is about a ±0.1
uncertainty in ∆G[0.02,0.3] due to relative luminosity.
The π 0 cross section measured at PHENIX1) agrees
with theory expectations within the theoretical scale
uncertainty. This theoretical scale uncertainty was included in the expectation for ALL in the GRSV fit, andit’s impact on the ∆G[0.02,0.3] was similarly evaluated.
This led to a sizeable uncertainty for negative valuesof ∆G.
†∗1∗2

Condensed from the article in PRL, Vol.103, 012003 (2009)
RIKEN BNL Research Center
Stony Brook University- 63 -

References
1) A. Adare, et al. Phys. Rev. D 76, 051106 (2007)
2) D. de Florian, R. Sassot, M. Stratmann, and W. Vogelsang, Phys. Rev. Lett. 101, 072001 (2008).
3) M. Glück, E. Reya, M. Stratmann, and W. Vogelsang,
Phys. Rev. D 63, 094005 (2001).

0.1
0.1

20
20

BB
BB
GS−C
GS−C
DSSV
DSSV
GRSV
GRSV
LSS
LSS

0.08
0.08
0.06
0.06

2
χχ
2

(1)

0 0

L++
1 N++ − RN+−,R =P1 P2 N++ + RN+−
L+−

ππ
AA
LLLL

ALL =

0

AπLL results from 2005 and 2006 significantly constrain the gluon spin contribution to the protonspin.
We find ∆G[0.02,0.3] = 0.2 ± 0.1(stat) ±0.1(syst)+0.0−0.4 (shape)±0.1(scale), and a consistent constraint at ∼ 3σ. Additional data from the Run9 RHIC
run will further constraint∆G[0.02,0.3] , while the first√measurements at s = 500 GeV will allow access to alower x range.

2∆ χ =9∆ χ 2 =9

15
15

0.04
0.04
0.02
0.02

10
10

00

2

∆ χ∆2χ=1=1

−0.02
−0.02
−0.04
−0.04

(a)
(a)

22

pDIS
(BB)
pDIS
(BB)
uncertainty
uncertainty(b)
55 (b)
44

66

10 12
12
88 10
(GeV/c)pp (GeV/c)−1 −0.5−0.5x=[0.02,0.3]
0.5 1 1
−10 0 0.5x=[0.02,0.3]
2 2
2=4 GeV∆∆GG(µ(2µ=4
GeV ) )

TT

0

Fig. 1. (a) AπLL vs. pT compared with different expectations based on fits to DIS data. (b) Constraint on∆G[0.02,0.3] based on the different fits.

χ2
χ2

Polarized Deep Inelastic Scattering (DIS) data haveshown the spin of the quarks only contributes about∼ 25% of the proton spin2,3) , implying that the remainder of spin is either from the gluon spin contribution, ∆G, or the orbital angular momentum of thequarks and gluons.
∆G can be accessed in polarized proton collisions bymeasuring the double helicity asymmetry, ALL , which
is defined as

2020
2

1515

1010

5

5

−1.5
−1.5

StatOnly
Only
Stat++∆∆RR−∆RR−∆++∆∆PP−∆PP−∆

2∆ χ∆ χ=9=92∆ χ∆ χ=1=1
2"∆ G=−1.05""∆ G=−1.05"−1−1"∆ G=0""∆ G=0"

−0.5
−0.5

0

0

"std"
"std"

0.5
0.5

1
1.5
1
1.5
x=[0.02,0.3]
2
x=[0.02,0.3] ( µ 2 =4 GeV
∆G
2 )
GRSV
( µ 2 =4 GeV )∆ GGRSV

Fig. 2. Constraint on ∆G[0.02,0.3] using the GRSV fit result
to DIS data. Impact of two primary systematic errors
are shown.

RIKEN Accel. Prog. Rep. 43 (2010)

Measurements of transverse single-spin asymmetry of single electrons
from open heavy flavor decays in polarized p + p collisions at√
s = 200 GeV at PHENIX†
S. Dairaku∗1 for the PHENIX Collaboration[Transverse Spin, Asymmetry, PHENIX]

where P is the absolute polarization value measured↑(↓)
by the RHIC polarimeters, and NL(R) is the numberof electrons scattered to the left (right) when the direction of beam polarization is vertically upwards (downwards). The detected electrons used for the calculationof AN include electrons from background processes, because of which the measured inclusive asymmetry canbe diluted. We can extract the asymmetry in heavy
flavor production (AHF
N ) from the measured inclusive
asymmetry (Aincl
N ) as follows:
AHF
N =

bg
Aincl
N − rAN,1−r

The dominant background source in this measurementis π 0 2) . Some previous results have indicated that
AN in π 0 production at mid-rapidity at PHENIX iszero3) . Therefore, we assumed that Abg
N is zero in thisstudy. The background fraction (r) is determined byusing a cocktail of the contributions from backgroundprocesses2) and by the converter technique, in which
the electron spectra measured with an additional photon converter introduced into the acceptance region arecompared with those recorded without the converter2) .
Measurements have been carried out on a data sample with an integrated luminosity of 2.7 pb−1 in transversely √polarized p + p collisions at a center-of-massenergy s = 200 GeV in 2006. The results for the
AHF
N of single electrons from open heavy flavor decays
are shown in Fig. 1. The left and right plots show the+
AHF
N values for positive charge: p+p → e +X and for−negative charge: p+p → e +X, respectively. The obof the single electrons from heavy flavor
served AHF
Ndecays are significantly smaller than those predicted
theoretically for D-meson production with a maximum
gluon Sivers function1) , which is greater than 10% in
the kinematic region of our measurements (xF ∼ 0).
Therefore, the obtained results could reject the maximum gluon Sivers function1) .

AN

Using the PHENIX detector at the Relativistic Heavy
Ion Collider (RHIC), we measured the transverse singlespin asymmetry (AN ) of single electrons from open
heavy flavor decays. The preliminary results of AN
measurements at mid-rapidity at PHENIX are presented here.
A number of mechanisms based on quantum chromodynamics have been proposed for explaining theobtained AN , and measurements in different processes
have played complementary and important roles in theattempt to understand AN . At RHIC energy, AN in
open charm production was suggested to probe thegluon Sivers function1) , which includes the correlation
between the transverse momentum of an unpolarized
parton in a transversely polarized nucleon and the nucleon polarization vector. Because open charm production is dominated by the gluon fusion process at RHIC
energy and the gluon’s transversity is zero, there is no
significant contribution to AN in open charm production from the Collins function, which describes the correlation between the transverse spin of a fragmenting
quark and the transverse momentum of the produced
hadron. Therefore, the measurement of AN in open
charm production at RHIC can help in probing of thegluon Sivers function.
AN is determined using the following equation:


↑ ↓
N
N
−
NL↓ NR↑1σ↑ − σ↓
L R

,
(1)
= 
AN ≡
σ↑ + σ↓P
NL↑ NR↓ + NL↓ NR↑

0.25
0.2
0.15

0.25

p + p ψ e + + X at

s = 200 GeV ( 2006 ) p + p ψ e - + X at
0.2

heavy flavor decay electrons( |ǯ| < 0.35 )

0.15

0.1

0.1

0.05

0.05

-0

-0

-0.05

-0.05

-0.1

-0.1

-0.15

-0.15

-0.25
0

-0.2

Vertical scale uncertainty 5%

0.5

1( |ǯ| < 0.35 )Preliminary

Preliminary-0.2

s = 200 GeV ( 2006 )heavy flavor decay electrons

1.5

2

2.5

3

-0.25

3.5
4
PT (GeV/c)

Vertical scale uncertainty 5%
0.5

1

1.5

2

2.5

3

3.5
4
PT (GeV/c)

Fig. 1. AHF
of single electrons from heavy flavor decays asNa function of pT .

(2)

References
1) M. Anselmino, M. Boglione, U. D’Alesio, E. Leader, andiswhere Abg
thebackgroundasymmetry
and
r
is
the
N
F. Murgia: Phys. Rev. D 70, 074025 (2004).
background fraction defined as r = σbackground /σinclusive .
∗1

Department of Physics, Kyoto University, Japan2) S. S. Adler et al.: Phys. Rev. Lett. 96, 032001 (2006).
3) S. S. Adler et al.: Phys. Rev. Lett. 95, 202001 (2005).

- 64 -

1

RIKEN Accel. Prog. Rep. 43 (2010)

Measurement of direct photon using virtual photon method in√
s = 200 GeV d+Au collisions at RHIC-PHENIX
Y.L. Yamaguchi,∗1 Y. Akiba, T. Gunji,∗1 and H. Hamagaki,∗1[Direct photon, virtual photon method, Low pT]

104

3

1

• Virtual direct photon decays• Hadron decays• Photon conversions• Combinatorial background• Cross pairs from π 0 , η → 2γ(or γe+ e− ) →e+ e− e+ e−
The pairs from photon conversions are removed by
a cut on the orientation of the pair in the magnetic
field2) . The combinatorial background is computed using a mixed-event technique. Cross pairs are evaluatedby comparing the like-sign pair distributions between
the real and simulated distributions. Finally, the correlated e+ e− pair mass distribution that consists ofpairs from known hadron decays and virtual photon
decays is obtained after background subtraction.

AuAu 0-20% x102102
10mass distribution contains several components fromdifferent sources, which are listed below.

AuAu MB x104

103

3

Ed3N/dp (GeV-2c3) or Ed σ/dp (mb GeV-2c3)

Direct photons are one of the most important probes
to investigate properties of the matter created by heavy
ion collisions since they leave the medium without
strong interaction. Thermal photons from the Quark
Gluon Plasma (QGP) are considered to be the primarycontributor in 1.0 < pT < 5.0 GeV/c1) and are of special interest.
In the PHENIX experiment, two different analysis
methods, namely, a “real” photon method and a “virtual” photon method, have been developed. The real
photon method using an electomagnetic calorimeterhas been used successfully for pT > 4.0 GeV/c andthe virtual photon method is employed for 1.0 < pT <5.0 GeV/c. Direct photon spectra both in p+p and
Au+Au collisions have been successfully measured using the real and virtual photon methods, as shown in
Fig 1. A clear excess over the binary scaled p+p result

AuAu 20-40% x10
p+p

10-1

3

10-2
-3

10

10-4
10-5
-6

10

10-7 1

2

3

4

5

6
7
p (GeV/c)T

Fig. 1. Direct photon spectra in p+p and Au+Au collisions
as a function of pT .

(shown by the dotted line) is seen in Au+Au collisionsfor 1.0 < pT < 3.0 GeV/c. However, the observed
excess cannot be concluded to be of thermal origin at
this moment. Data on d+Au collisions are needed toevaluate nuclear effects such as the Cronin effect andnuclear shadowing since nuclear effects may increaseor decrease the photon yield in low pT region. Efforts
are being made to measure the low-pT direct photons
in d+Au collisions using the virtual photon method.
The current status of the analysis in 200GeV d+Au
collisions are reported in this report.
All combinations of electrons and positrons in asame event are condidered. The obtained e+ e− pair
∗1Center for Nuclear Study (CNS), University of Tokyo- 65 -

Fig. 2. Correlated e+ e− pair mass distribution in d+Au
collisions for pT > 1.0 GeV/c (left) and the pT -sliced
e+ e− pair mass distributions for Mee < 300 MeV/c2
and 1.0 < pT < 6.0 GeV/c (right).

The left panel in Fig. 2 shows the correlated e+ e−pair mass distribution in d+Au collisions for pT >1.0 GeV/c. The d+Au data has abundant statistics
so that even Ψ is clearly visible around 3.7 GeV/c2 .
The right panel in Fig. 2 shows the pT -sliced e+ e−pair mass distributions for Mee < 300 MeV/c2 and1.0 < pT < 6.0 GeV/c, which are suitable for virtual direct photon measurements. The results up to
6.0 GeV/c are expected to be obtained for d+Au collisions. Although some corrections should be made inorder to obtain the direct photon spectrum in d+Au
collisions, the d+Au result is promising.
References
1) S. Turbide, et al.: Phys. Rev. C 69, 014903 (2004).
2) A. Toia: arXiv:0711.2118 [nucl-ex] (2007).

RIKEN Accel. Prog. Rep. 43 (2010)

Azimuthal angle dependence of neutral pion suppression in√sN N = 200 GeV Au+Au collisions at RHIC-PHENIX
Y. Aramaki∗[Quark Gluon Plasma, Jet quenching, Parton energy loss]∗

Center for Nuclear Study, Graduate School of Science, University of Tokyo, Japan- 66 -

tainty, respectively. The bands on the measured points
show pT correlated systematic uncertainties on themeasurement of the azimuthal anisotropy of in-planeand out-of-plane, respectively. As shown in Fig. 2, eventhough ASW reproduce the in-plane RAA has slightly
difference at lower pT .
0.3

0.3

MPC

PHENIX Preliminary

0.2

0.2

0.1

0.1

0
-0.10
0.3

π 0 v20 - 10 %

2

4

0
6

8

10

12

14

-0.10
0.3

0.2

0.2

0.1

0.1

0
-0.1
0.3

0

20 - 30 %

2

4

0
6

8

10

12

14

0.2

0.3

0

2

4

30 - 40 %
2

4

6

8

10

12

14

6

8

10

12

14

6

8

10

12

14

0.1

0
-0.1

-0.1

10 - 20 %

0.2

0.1

0

40 - 50 %

2

4

0
6

8

10

12

14

-0.10

pT (GeV/c)

50 - 60 %2

4

T

RAA(p ,)

Fig. 1. Azimuthal anisotropy of neutral pion v2 with MPC
for each 10% centrality classes.

0

It has been observed in central Au+Au collisions
at Relativistic Heavy Ion Collider (RHIC) that theyield of neutral pion at high transverse momentum(pT >5 GeV/c) is strongly suppressed compared to theone expected from p + p collisions scaled by the number of binary collisions. This suppression is considered
to be due to the energy lost by hard scattered partonsin the medium (jet quenching), which results in a decrease of the yield at a given pT . Many theoreticalmodels have been proposed to understand the partonenergy loss mechanism. GLV method1) is one of thecalculations that predicts that the magnitude of energy loss is proportional to square of the path length.
Studying the path length dependence of energy loss
should help in understanding of energy loss process.
The Muon piston calorimeter (MPC) to determine
the reaction plane is used for measuring the azimuthal
anisotropy of neutral pion at PHENIX. MPC is madeof PbWO4 . Even though MPC is similar rapidity coverage to the detector which is used in the previous measurement, the reaction plane determination is expected
to be improved due to good energy resolution. Figure 1
shows the azimuthal anisotropy of neutral pion as afunction of pT for each centrality class. The nuclear
modification factor (RAA ) for each azimuthal angle iscalculated by using them.
Recently theoretical models (ASW2) , HT3) andAMY4) ) to describe parton energy loss mechanism
which involve the time-evolution of the medium produced at RHIC have been proposed. These models
succeeded in reproducing the centrality dependence ofRAA (pT )5) . The measured RAA is compared with one
model (ASW) of them. Figure 2 show the RAA as afunction of pT and azimuthal angle for centrality 2030 % and ASW model. Closed and open points show
the measured RAA for in-plane and out-of-plane, respectively. Since the produced medium after the collisions is assumed to be almond shape, the in-plane
path length is shorter than out-of-plane. This difference of the path length is reflected in the RAA for eachazimuthal angle. Solid and dashed lines show the theoretical curve for ASW model of in-plane and out-ofplane, respectively. The central big band shows thepT correlated systematic uncertainty on the azimuthal
angle integrated RAA . The right and the left small
bands show the number of collisions uncertainty from
Glauber calculation and p + p normalization uncer-

0.9
0.8
0.7

0 <

PHENIX Preliminary

< 15
< 90

20-30 %

0.6
0.5
0.4
0.3
0.2

6

8

10

12

p (GeV/c)

14

16

T

Fig. 2. The RAA as a function of pT and azimuthal angle from the reaction plane for centrality 20-30 % andASW.

We can also estimate the averaged path length bymeasuring the azimuthal angle from reaction plane andmapping it into the shape of the participant region,
which can be calculated by Glauber model for each
impact parameter (centrality).
References
1) M. Gyulassy et al.: Phys. Lett. B538, 282 (2002).
2) T. Renk et al.: Phys. Rev. C75 031902 (2007).
3) A. Majumder et al.: Phys. Rev. C76 041902 (2007).
4) G-Y. Qin et al.: Phys. Rev. C76 064907 (2007).
5) S.A. Bass et al.: J. Phys. G35 104064 (2008).

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Systematic Measurement of ω Mesons in p+p, d+Au, and A+A√
Collisions at sN N = 200 GeV at RHIC-PHENIX
M.Ouchida∗1 D.Sharma2 K.M.Kijima1 V.Riabov3 Y.Tsuchimoto4 Y.Riabov3 Y.Nakamiya1

∗1

∗2
∗3
∗4

1/(2πmT ) d2N/dmT dy

mode, e+ e− for the low pT region in a minimum-bias
event, and π 0 γ for the high pT region in three centrality values (the value used to characterize the heavy-ion
collisions), namely, 0-20%, 20-60%, and 60-92%. Thelines represent estimated yields from p+p collisions,after scaling by the number of collisions in which there
was no a nuclear matter effect. If data points lie below
the lines for higher centrality values, we can suggestthat the invariant yield is suppressed in the high pT
region for higher centrality values; this, in turn, implies that some jets from hard collisions are quenchedwhen they pass through the dense and hot medium
created by heavy-ion collisions.
We are preparing a publication on this result. The
target date for submission is in summer 2010.

10

ω → e+e- dAu, MB (run8 prelim.)ω → π00γ +dAu,
MB (PRC 75 051902)
ω → π+π - π- dAu, MB (PRC 75 051902)
ω → e e pp, MB (run5 prelim.)ω → π00γ pp, MB (PRC 75 051902)
ω → π γ pp,
ERT (run5 prelim.)ω → π00π++π-- pp, MB (PRC 75 051902)
ω → π π π pp, ERT (run5 prelim.)

1

10-1

10-2
-3

10

10-4
-5

10

-6

10

10-7
-8

10

-9

10
10

-10

10-110

2

4

6

8

10
12
mT - mω (GeV/c 2)

Fig. 1. The mT spectra corresponding to p+p (circle points) andd+Au (triangle points) collisions. The solid line and dotted line
represent the fitted Levy function for p+p and d+Au.
610

1/(2πmT ) d2N/dmT dy

The measurement of hadrons under extreme conditions created by relativistic heavy-ion collisions is partof an interesting study being carried out as a part of
the quest to observe the QCD phase transition to quark
gluon plasma (QGP).
The ω meson that has vector properties and both
lepton and hadron decay modes serves as a useful probe
in the study of the mechanism of particle production in
the collision. We measured ω mesons in p+p, d+Au,
and A+A collisions in both leptonic and hadronic decay modes. The systematic measurement can be carried out over a wide kinematic range since low pT values can be included in the leptonic decay mode andhigh pT values can be included in the hadronic decaymode.
The dielectron decay mode, ω → e+ e− is reconstructed in a Crenkov detector that can identify electrons and positrons. In an event, the source of any
electron or positron is unknown, and therefore, all electrons and positrons are combined into pairs. This results in a large combinatorial background, especially incentral Au+Au collisions because of their high multiplicity. The background is computed by a mixed event
technique, which combines tracks from different eventswith similar event topology.
The first step for both hadronic and photonic analysis based on the ω → π + π − π 0 and ω → π 0 γ is to reconstruct π 0 candidates by combining photons pairs andapplying a pT -dependent cut around the mass of theπ 0 . Candidates (included in the combinatorial background) are combined with a third photon for ω → π 0 γ
or with two unidentified charged tracks (assumed tobe π mesons) for ω → π + π − π 0 . Owing to the highmultiplicity and low S/B associated with it, cut optimization was performed in the case of A+A analysis.
For p+p and d+Au analysis, raw yields were extracted
by fitting the pT slices of the invariant mass distribution, as shown in the figures. In A+A analysis, thebackground is subtracted by estimating correlated anduncorrelated backgrounds from two combinations of amixed event technique.
Fig.1. shows the obtained invariant cross sectionfor ω production in p+p collisions and minimum bias√
d+Au at sN N = 200 GeV as a function of pT . The
results indicate a good agreement among different decay channels. Fig.2. shows the spectra corresponding
to Au+Au collisions, as measured in the two decay

Au+Au 200 GeV
ω -> e+e-, min. bias × 102
ω -> π0γ , min. bias ×4102
ω -> π0γ , 0-20% × 10
ω -> π0γ , 20-60% × 10
ω -> π0γ , 60-92%

5

10

104
3

10

102
10

1

10-1

10-2
-3

10

10-4
-5

10

-6

10

10-7
-8

10 0

2

4

6

8

10
mT - mω (GeV/c 2)

Fig. 2. The mT spectra corresponding to Au+Au for different cenHiroshima University
Weizmann Institute, Israel
PNPI, Petersburg Nuclear Physics Institute, Russia
Center for Nuclear Study, University of Tokyo

trality value. The centrality increases from bottom to top. Thelines represent estimated yields from p+p collisions, after scalingby the number of collisions.

- 67 -

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Measurement of J/ψ production in ultra-peripheral Au+Au√
collisions at sN N = 200 GeV during RHIC RUN-7†
A. Takahara∗1| FAu (p2T ) |2 =| 3sin(RpT ) − RPT cos(RpT ) 2|(RpT )3 (1 + (apT ))(1)

In this case, R = 6.7 fm and α = 0.7 fm5) . Please notethat the function is not calculated on the bias of any
prperties of the detector.
The high-mass distribution of e+ e− pairs analysed in
RHIC RUN-7 UPC . However, the exponential curve
may not be accurate. We may find differences between†∗1χ2 / ndf
Prob
a
c

22
20
18

8.078 / 7
0.3258156.7 ± 59.3
2.809 ± 0.811

16
14
12
10
8
6
4
2
0
2

2.2

2.4

2.6

2.8

3

3.2

3.4

3.6
3.8
4
mass (GeV/c^2)

Fig. 1. Invariant mass distribution of e+ e− pairs fitted tothe combination of a dielectron continuum (exponential
distribution) and a J/ψ (Gaussian) signal. Exponential
curve is fixed by RUN 4 simulation.

dN/dpt(counts)

In this paper, we present the RHIC RUN-7 measurements of the photoproduction of J/ψ and of the twophoton production of high-mass e+ e− pairs in ultraperipheral nucleus-nucleus interactions of Au nuclei√
at sN N = 200 GeV. Ultra-peripheral collision(UPC)
refers to a collision in which impact distance is greator
than the sum of the nuclear radii with no nuclear overlap. The proposed of use of UPCs to study photoproduction at hadron colliders has attracted considerable
interest in recent years1–3) . UPCs can be used for determining gluon density at low x. Similar measurements performed in RHIC RUN-4 have been reportedin4) .
UPC events are tagged by the emission of forward
neutrons sted the Coulomb excitation of one or bothAu∗ nuclei.
The event triggers have the following requirments;
1)There should be no coincident signals from the beambeam counters; 2) a 2x2 tile EMCal trigger ERT witha trigger threshold of 0.8 GeV is needed; 3)the energyof the beams to the ZDCs should be aminimum of 30
GeV. Futher, the offline requirments are Zvertex≤30
cm, only two charged particles , EMCal cluster withno dead or noisy towers within 2 × 2 tile, and EMCal cluster energy of over 1 GeV/c for one memberof the pair. The UPC J/ψ measurement is based onmain purely electromagnetic process. The high-masse+ e− pairs distribution will be combination of exponential and Gaussian(J//ψ) distribution. In this report,
the exponential curve was plotted on the basis of theRUN-4 simulations4) since RUN-7 simulation have notbeen performed yet.
The mass distribution is shown in Fig. 1. There are
17 e+ e− pairs between 2,8 GeV/c and3.2 GeV/c. In
RUn-4 there were 12 e+ e− pairs RUN 44) . Fig. 2 isthe dN/dpT distribution of the pairs.
The squared form factor of a Au nucleus is represented ascounts[Nuclear structure]87

χ2 / ndfProb
p0

24.29 / 18
0.145613.03 ± 5.45

0.7

0.9
1
pt(GeV/c)

6
5
4
3
2
1
0
0

0.1

0.2

0.3

0.4

0.5

0.6

0.8

Fig. 2. dN/dpT distribution of the pairs with me+ e− ≥ 2
GeV/c2 fitted to the (truncated) Au nuclear form factor

RUN-7 and RUN-4 continuum curves because a new
detector HBD was installed in RUN7.
References
1) G. Baur, K. Hencken, D. Trautmann, S. Sadovsky, and
Y. Kharlov: Phys. Rept. B, 359 (2002).
2) C. A. Bertulani, and S. R. Klein, J. Nystrand, Ann.
Rev. Nucl. Part. Sci. B, 271 (2005).
3) A. Baltz et al.: Phys. Rept. B 171 (2008).
4) S. Afanasiev PHENIX Collaboration: Phys. Lett. B
321(2009).
5) K. T. R. Davies and J. R. Nix: Phys. Rev. B 1977
(1976).

Department of Physics, University of Tokyo- 68 -

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

√
Neutron asymmetry measurement with s=500 GeV polarized
proton collision at RHIC-PHENIX
M. Togawa, Y. Goto, and S. Dairaku∗1 for the PHENIX collaboration∗1

Department of Physics, Kyoto University- 69 -

Raw asym. / CNI pol.

Raw asym./CNI pol. for YELLOW beam
0.1

0.08
0.06
0.04
0.02
0

-0.02
-0.04
-0.06
-0.08
-0.10

0.5

1

1.5

2

2.5

3

φ

Fig. 1. φ-dependent asymmetries for transverse (open circle) and longitudinal (open square) runs.

Raw LR asymmetry

Raw LR asymmetry
0.02

0.01

0

-0.01

-0.02
0

20

40

60

80

100
120
Crossing ID

Fig. 2. Raw LR asymmetry (=(NL − NR )/(NL + NR )) as afunction of RHIC beam bunch ID. Circles and squares
indicate spin down and up, respectively, as determinedby accelerator database.
A N vs. p for leading neutrons = 62 GeVTAN

One of the main programs at the Relativistic Heavy
Ion Collider (RHIC) is the measurement of polarized
gluon distribution function in the proton by√using longitudinally polarized proton collisions at s = 200
GeV1) . In the RHIC ring, vertical polarization is stable. The spin rotator magnets located around the experimental area rotate the spin vector by 90◦ to enable longitudinal collisions at the PHENIX interaction
point. The PHENIX local polarimeter system is used
to conﬁrm that protons are longitudinally polarized at
the interaction point during a run, by measuring a remaining transverse neutron asymmetry2) .
The local polarimeter system consists of a ZeroDegree Calorimeter (ZDC) and a position-sensitive
Shower-Max Detector (SMD)3,4) . The ZDC and SMD
cover the forward and backward directions with a maximum angle of 2.8 mrad., including zero degree4) . In
the 2009 run at RHIC, an experiment√was carried out
using polarized proton collisions at s = 500 GeV
for the ﬁrst time. It was observed that the neutron
asymmetry remains ﬁnite at this high energy. Figure 1 shows the φ-dependent asymmetries observed intransverse and longitudinal runs. It is clear that theasymmetry is ﬁnite in the transverse run and almost
zero in the longitudinal run.
Thus far, the asymmetry was calculated from theraw data recorded using the standard PHENIX DAQ
and therefore the statistical precision was limited by
the DAQ bandwidth. In this run, we implemented thescalar mode, in which we recorded the number of hit
counts in the right and left parts of the SMD. Figure 2
shows the left-right asymmetry as a function of RHIC
beam bunch ID obtained from the counts in 5 min.
This ﬁgure demonstrates that precise bunch-by-bunchasymmetry can be achieved within such a short time.
Presently, calculation of asymmetry using the scalardata is carried out by the standard PHENIX online
monitor system, and the results are sent to the accelerator database. The data are used for accelerator
tuning in the 2009 run.
In such forward kinematics, information on the pT
dependence of asymmetry may be obtained from theresults at diﬀerent colliding energies, where pT is calculated using the relation of pT ∼ En sin(θ). Figure
3 shows the asymmetry as a function of neutron pT
evaluated using a full√detector simulation. The amplitude increases with s. This new data will help us
to understand the production mechanism of neutron
asymmetry.

0.1

Scaling uncertainties, 9.6, 11 and 22%
for 62, 200 and 500 GeV, not includeds = 200 GeV
s = 500 GeV

0.4 < x F

0.05

PH ENIX

0

preliminary-0.05

Neutron
-0.1
-0.15
-0.2
0

Estimated p variation (2 RMS) in each bin
T

0.1

0.2

0.3

0.4

0.5
p (GeV/c)T

Fig. 3. Single transverse spin asymmetry as a function ofneutron pT , evaluated by a full simulation. The asym√
metry increases with s and possible from the pT dependence.

References
1) G. Bunce et al.: Ann. Rev. Nucl. Part. Sci. 50, 525(2000).
2) Y. Fukao and M. Togawa et al.: Phys. Lett. B650, 325(2007).
3) C. Adler et al.: Nucl. Instr. & Meth. A470, 488 (2001).
4) A. Deshpande et al.: RIKEN Accel. Prog. Rep. 37, 246(2004).

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Cosmic-ray background in PHENIX detector
D.S. Blau,∗1 and K. Okada

T1 ·
∗1

1
R
1
R
6.5 × 1010···=
= 0.32,
T0 RcrossR
20300 10 × 106

Russian Research Center ”Kurchatov Institute”, Moscow,
Russiawhere T0 and T1 are data-accumulation periods, and R(Rcross ) is the rate of collisions (accelerator crossings).
With this factor, the rate of cosmic-ray (Fig. 2) andthe background rate in the collision data (Fig. 3) areconsistent.
In this report,√ the background component in p + p
collisions at s = 200 GeV identiﬁed using ToF information is explained by cosmic-ray contribution. At ahigh center-of-mass energy (e.g., 500 GeV), we need tohandle rarer signals. The ToF information is essential
to reduce cosmic-ray background.
References
1) K. Adcox et al.: Nucl. Inst. Meth. A 499, 469 (2003).

Fig. 2. Energy distribution of cosmic-ray data obtained
over 20,000 s. The clusters (the top histogram) are
divided into two groups by the shape cut. The bottom
histogram shows good shape clusters.

entry/0.5GeV

High-energy photons are important probes in theﬁeld of nuclear physics. They provide early-stage information on nuclear collisions. At PHENIX1) , photons are detected by the electromagnetic calorimeters(EMCals). One problem is a cosmic-ray event can be
identiﬁed as a direct photon event. Fig. 1 shows two
examples of cluster shapes in EMCals made by cosmicrays. The clusters with the shape shown in Fig. 1(a)can be easily eliminated; however, those with the shape
shown in ﬁg.1(b) are retained. Competition exists between the rates of the real signal and the cosmic event.
Since the signal rate is considerably lesser in p+p collisions, the contribution of cosmic-rays is a more serious
problem in p + p collisions than in Au + Au collisions.
In 2007, control data were obtained when there was
no activity in the accelerator for a total period of about
20,000 s. Fig. 2 shows the energy spectra of this data
set. The EMCal miscalculates the energy deposit ofcosmic-ray hits because it is calibrated for photons
coming from the collision.
Fig. 3 shows the energy spectra for√a total of 6.5 ×1010 events triggered by p + p (at s = 200 GeV)
collisions. The thick line represents all the clusters, thedashed line represents the clusters with |T oF | < 5 ns,
and the thin line represents the clusters with |T oF | > 5
ns. Since the beam crossing interval is about 100 ns, a
reduction in background by a factor of 10 is expected in
the case of |T oF | < 5 ns. The background is dominant
in the high-energy region.
Two plots (Figs. 2 and 3) are compared by multiplying a factor calculated using the data-accumulation
period and the probability of having collisions in coincidence. The factor is obtained using the following
formula:

104

10

3

102

10

1
10

Fig. 1. Cosmic ray cluster examples. Each square corresponds to a EMCal tower. The hight is proportional tothe pulse hight.

- 70 -

15

20

25

30

35

40
E[GeV]

Fig. 3. Spectra of photon-like clusters with 6.5×1010 minimum bias collision triggered data (RHIC Run5pp). The
thin-line histogram is for clusters out of collision timing(|T oF | > 5 ns).

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Vernier Scan Method to Reduce Relative Luminosity Uncertainties†
D. Kawall,∗1,∗2
Introduction
The PHENIX experiment at the Relativistic Heavy
Ion Collider (RHIC) has measured the asymmetry,of longiALL , in inclusive π 0 production from collisions√
tudinally polarized protons beams at s = 200 GeV1) .
The asymmetry is defined as :
ALL =

L++
1 N++ − RN+−
(1)
, where R =P1 P2 N++ + RN+−
L+−

and N++ is the π 0 yield from collisions of protons in helicity states ++, and N+− is for +−, P1 , P2 are beampolarizations and L++ and L+− are the corresponding beam luminosities. The asymmetries are of great
physics interest because of their leading-order sensitivity to the contribution of gluon spin, ∆g, to the spinof the proton2,3) .
Determining the asymmetry in cross-section requires
a measurement of the relative luminosity of the colliding beams, R = L++ /L+− , to higher precision thanthe expected asymmetries in particle production. The
measurement of R has become increasingly importantfor several reasons. First, a comprehensive global fit
to polarized deep-inelastic scattering data and ALL
measurementsof jets and π 0 at RHIC, indicate that1
∆g is small ( 0 ∆g(x, Q2 )dx ≈ −0.084 at Q2 = 10
GeV2 ), and the expected asymmetries are small3) .
For instance, AπLL < 5 × 10−3 for pπT < 20 GeV at√
s = 500 GeV3) . Reducing the uncertainty on ∆gwill thus require measurements of R at the level of a
few×10−4 . We also note that the greatest uncertainty
on ∆g comes from the low-x region, which is accessedprimarily from low pπT where the predicted asymmetries are very small. Second, at the design luminosityof RHIC, L = 1032 cm−2 s−1 , there will be > 25%
chance of two or more collisions per bunch crossing.
Currently PHENIX measures the beam luminosity bycounting coincidences between two Beam-Beam Counters (BBCs), located on either side of the interaction
region, which detect pp collision by-products4) . They
count at most 1 event per bunch crossing, and so become nonlinear at high rates. The amount of nonlinearity can be modeled by measuring the BBC efficiency for detecting pp collisions. In this technique, themachine luminosity, L, is measured during a vernier
scan5) , as is the peak rate Ṅ observed in the BBC. We
then extract an effective cross-section for the BBC,
σBBC from the relation Ṅ = LσBBC . Knowing the
pp inelastic cross-section allows us to extract the BBC
efficiency. The disadvantage of this approach is that
∗1
∗2

RIKEN-BNL Research Center, Brookhaven National Laboratory, Upton, NY, USA
Department of Physics, University of Massachusetts,
Amherst, MA, USA- 71 -

σBBC is seldom determined to better than 10% dueto the uncertainty on some collider parameters suchas the focusing β ∗ , which is required to calculate themachine luminosity, and which is only known to about
10%. Still, event-generator6) plus detector simulations
suggest we can determine R to ≤ 10−3 at design luminosity with these techniques.

Fig. 1. Effective BBC cross-section in millibarns versus collision rate in Hz.

Vernier Scan Approach
To do better, we note that σBBC should be a constant, dependent primarily on the BBC coverage in ηand φ, and in particular it should be independent of
the rate. Now consider what happens when we extract
σBBC = Ṅ /L from vernier scans performed at low rateand high rate. At low rate, Ṅ is linear in the “true”
rate, and the value extracted for σBBC is reasonable.
At high rate, Ṅ under-counts. The denominator, L,
comes from measuring the transverse sizes of the colliding bunches, and is largely independent of rate effects.
Taking the ratio at high rate then leads to a smallervalueof σBBC as seen in Fig. 1 from a vernier scan at√
s = 500 GeV at PHENIX. The fractional difference
observed in σBBC is equal to the fractional correction
required on the rate. This method is independent ofpoorly known collider parameters, which cancel whencalculating the fractional changes. The new methodshould reduce the uncertainty δR by at least a factor
two compared to the approach above.
References
1) A. Adare et al., Phys. Rev. Lett. 103, 012003 (2009).
2) G. Bunce et al., Ann. Rev. Nucl. Part. Sci. 50, 525(2000).
3) D. de Florian et al., Phys. Rev. D 80, 034030 (2009).
4) M. Allen et al., Nucl. Instr. and Meth. A 499, 549(2003).
5) S. van der Meer, CERN ISR-PO/68-31, KEK68-64(1968).
6) PYTHIA 6.4, T. Sjostrand, S. Renna and P. Skands,
JHEP 0605:026 (2006).

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Method For Determining Relative Luminosity From Detection
Probabilities
A. Manion,∗1 K. Boyle,∗2 and A. Deshpande∗1

1 N++ − RN+−,PB PY N++ + RN+−

(1)

where PB , PY are the polarizations of the beams, N ’s
represent yields in collisions with same (++) and opposite (+−) beam helicities, and R is the relative luL++. Here L++ and L+−
minosity, deﬁned by R = L+−
are the beam luminosities for the diﬀerent spins. R
is typically measured by counting coincidences in the
Beam-Beam Counters (BBCs), detectors that trigger
on low energy particles in a pseudo-rapidity range∆η = (3.1−3.9) on the North and South sides of the interaction point. It is usually assumed that the numberof BBC coincidences is proportional to the number ofcollisions, a convenient assumption because the BBCs
do not collect enough information to accurately countcollisions. This is justiﬁed when the number of collisions per beam crossing averages much less than 1, but
breaks down at high luminosities when multiple collisions become common, resulting in under-counting.
One possible solution to this counting problem is to
use the probability of measuring zero in the BBCs. Actually, three probabilities are required: the probability of measuring zero in the North detector, P N (0) =e−N (λ+λN ) , the South detector, P S (0) = e−S (λ+λS ) ,and zero in both detectors,
P

N,S

0.074
0.072
0.07
0.068
0.066
0.064
0.062
0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

0.18

0.2

Fig. 1. ZDC counts over BBC counts vs. a collision Rate
proxy (ZDC “N or S” triggers normalized to time).

N S λ = ln(P N,S (0)) − ln(P S (0)) − ln(P N (0)), (2)which can be used in a new deﬁnition of R. Experimentally, the probabilities involved can be measured
∗2

0.076

S

The deﬁnitions in the above equations are as follows:
λN and λS are the true rates of events capable of triggering only the North or only the South BBC, although
they are allowed in principle to cause an accidental coincidence. λ is the true rate of events capable of causing a real coincidence, although they may not. The ’s
are the eﬃciencies of the detectors, assumed to be constant over the sample in which R is being calculated.
These equations can be solved for the quantity

∗1

0.078

Rate

(0) = [P (0)][P (0)|N = 0]
= [e−N λ e−N λN ][e−S (1−N )λ e−S λS ]= eS N λ−S (λ+λS )−N (λ+λN ) .
N

References
1) A. Adare, et al. PRL, Vol. 103, 012003 (2009)∈N∈SλZDC/∈N∈SλBBCALL =using the ratio of events to beam crossings, for example, P S (0) = 1 − (NS /Ncrossings ).
When checking for systematic uncertainties in R, thetypical procedure is to take the ratio of coincidenceswith another set of North and South detectors, theZero Degree Caolrimeters. These cover ∆η = ±(6, ∞)and trigger on forward neutral particles. This means
they sample an independent class of physics, and thus
any asymmetry seen there gives an estimate of the systematic uncertainty in using the BBC to determine R.
Figures 1 and 2 show the results of the typical method
and the one outlined here applied to this procedure.
The typical method obviously suﬀers from rate eﬀects,
while the new method is relatively stable. The newmethod calculation here used only recorded data, but
in the future all live trigger data will be availible which
will signiﬁcantly reduce the uncertainty.

NZDC/NBBC

Measurement of ∆G, the gluon contribution to theproton spin, is an important part of the spin programat RHIC1) . In particular, it can be accessed throughmeasurements of double longitudinal spin asymmetries
in polarized proton collisions:

0.168
0.166
0.164
0.162
0.16
0.158
0.156
0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

0.18

0.2

Rate

Fig. 2. A ZDC to BBC ratio using the new deﬁnition vs.
a Rate proxy.

State University of New York at Stony Brook
RIKEN BNL Research Center- 72 -

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Installation and Tests of the PHENIX Muon Trigger RPCs†
M. Grosse Perdekamp∗1, Anselm Vossen∗1 and R. Seidl,∗2 for the PHENIX Muon Trigger Upgrade Group.
[Proton Spin Structure, W-Boson, Muon Trigger, RPCs ]The PHENIX collaboration at Brookhaven National Laboratory (BNL) prepares measurements ofthe proton quark- and anti-quark-helicity distributions
through the observation of parity violating single spin
asymmetries between muon yields from W-productionin polarized proton-proton collisions at RHIC. The
measurements
will be carried out at a center of mass√energy of s = 500 GeV and p-p collisions rates reaching up to 10 MHz.

NSF and are being developed and built by a group of
PHENIX collaborators from ACU, CIAE, Columbia,
Colorado, GSU, ISU, Hanyang University, Korea University, Morgan State, Muhlenberg, PKU, RBRC,
UCR and UIUC.

Fig. 2. Pre-assembly of 16 RPC-3 half octants at UIUC.

Fig. 1. Noise and high voltage test of two RPC-3 north half
octants in the RPC assembly laboratory at BNL.

The high rates require a two-component upgrade of
the PHENIX ﬁrst level muon trigger with the goal
to increase the rejection power of the existing muon
trigger by a factor 50: (1) New front end electronics
for the existing muon tracking chambers has been developed that transfers muon tracking information to
fast FPGA based trigger processor boards. The newfront end electronics was funded through the JSPS
and was successfully developed and installed by theLos Alamos, KEK, Kyoto, RIKEN Rikkyo and UNM
groups in PHENIX. (2) New dedicated muon trigger
Resistive Plate Chamber (RPC) stations were developed for insertion in the two existing PHENIX muon
spectrometers. The RPCs provide additional tracking
information and the timing information required forthe rejection of beam backgrounds on-line and cosmic
ray background oﬀ-line. The RPC timing information
will be also used to connect events at high rates to thecorrect collision and polarization information.
The RPCs, their front end electronics and the level
one trigger processors have been funded through the∗1∗2

University of Illinois, Urbana Champaign, USA.
Riken BNL Research Center, Upton, USA.

- 73 -

Fig. 3. Fully installed RPC-3 north detector stations seenfrom the RHIC accelerator tunnel in November 2009.

The RPC technology used was developed originallyfor the muon trigger detectors of the CMS experimentat the LHC. The PHENIX trigger RPC design follows
closely the design of the endcap muon trigger RPCs in
CMS1) . The bakelite RPC gas gaps for PHENIX havebeen manufactured by the CMS RPC detector laboratory at Korea University (KODEL) and delivered for
assembly to BNL. Figure (1) shows two PHENIX RPC
half octants during high voltage and noise testing in
the RPC assembly facilty at BNL and ﬁgure (2) shows
the pre-assembly of 16 RPC-3 half octant shells at the1nuclear physics laboratory at UIUC.
For the RHIC
√ data taking in 2009√with polarized p-p
collisions at s = 200 GeV and at s = 500 GeV twofull size RPC half octant prototypes were installed in
the south PHENIX muon spectrometer. In November
2009 the intallation of the ﬁrst full RPC-3 detector
station was completed in the north muon spectrometer.
RPC-3 north is shown in ﬁgure (3) after installation.
During detector assembly the muon trigger RPCs
are carefully tested for possible gas leaks, high voltage
stability and their performance with regards to detection eﬃciency, timing resolution and cluster size. This
tests are carried out with the help of dedicated test
stations for high voltage and gas leak testing and ina cosmic ray test stand. The cosmic ray test standholds up to 10 RPC detector modules and allows a detailed evaluation of the RPC performance. Figure (4)shows results for the detection eﬃciency versus RPC
high voltage for an RPC-3 north detector module. As
can be seen from the ﬁgure the eﬃciency reaches 95%
for a broad range of thresholds and high voltages of
9.5 kV or larger.

the south tunnel at the same z-position as the RPC3
South location. The prototypes were integrated in the
PHENIX data aquisition and slow control during the
run and their performance was found to be quite stable
and reliable.
Initially, the LV cable to the RPC2 did pick uphigh frequency electronics noise, which resulted in highnoise rates in most of the RPC2 area. After installing
an additional low pass ﬁlter, the noise rates dropped
and RPC2 became useable. Apart from a few noisy
readout strips, the noise rates stayed below the target
noise rate of 10 Hz/cm2 which will allow us to use thisdetector for triggering.
The readout of the data shows that the collision related particles can be nicely seen in the time distributions as shown in Fig. 5 for all non-noisy strips. Fitting
them with a Gaussian distribution shows, that thesepeaks can be described well with widths of only a few
ns.
The observed timing resolution is consistent withexpected contributions from the RPC-TDC resolution
and variations in hit position and cable lengths.
In fact it was found that for trigger operation a timing window shorter than the design value of 20 ns canbe used. The timing resolution is suﬃcient to reject
beam backgrounds and to connect the triggered eventto the correct polarization information.
RPC 2, Module A
0.00240.0022

RPC 2, Module B

163 / 37

0.002

Constant 0.00189 ± 0.00006

0.0018Mean

0.00160.0014

RPC 2, Module C-3

χ2 / ndf

9.83 ± 0.04

Sigma

1.54 ± 0.03

0.0012

0.6

× 10

0.5
0.4

-3

0.4

Constant 0.000505 ± 0.000031

0.35

Constant 0.000288 ± 0.000023

Mean

12.7 ± 0.1

0.3

Mean

18.3 ± 0.1

Sigma1.29 ± 0.05

0.25

Sigma

1.47 ± 0.08

0.3

0.1
0.1

0.00040.05

0.0002
-10

0

10

20

30 40 50 60
TDC value 106ns/44

RPC 3, Module A
0.00120.001
0.0008Fig. 4. RPC eﬃciencies for diﬀerent discriminator thresholds versus high voltage.

The assembly of the RPC-3 south RPC half octants
will be completed by April 2010 and RPC-3 south will
be installed during the RHIC summer shutdown 2010.
It is also expected that the assembly of the smaller upstream RPC trigger stations, RPC-1 south and northwill be completed during the summer√ of 2010. A ﬁrst
long RHIC run for W-physics at s = 500 GeV isscheduled for 2011.
Prototype Performance in RHIC Run 2009
During the 2009 RHIC run two full size half-octant
prototypes with similar layout and nearly identical dimensions to the ﬁnal RPC design were installed in
PHENIX. One prototype, RPC2, was located downstream of the south muon magnet in front of the MUID
gap 0, the second prototype, RPC3, was located in2- 74 -

0
-20

-10

0

10

20

30
40 50 60
TDC value 106ns/44

RPC 3, Module Bχ / ndf

319 / 402

0.8

Constant 0.000762 ± 0.000037

0.7

Mean

9.75 ± 0.07

0.6

Sigma

2.05 ± 0.08

0.5

× 10

χ2 / ndf

234 / 39

Constant 0.00065 ± 0.00004
Mean

12.4 ± 0.1

Sigma1.34 ± 0.05

10

20

30 40 50 60
TDC value 106ns/44

0
-20

10

20

30 40 50 60
TDC value 106ns/44

0.25
0.2

236 / 39

Constant 5.1e-05 ± 4.0e-06
Mean

25.7 ± 0.7

Sigma

9.49 ± 0.67

0.05

0.1
0

0

χ2 / ndf

0.1

0.2

-10

×10

0.15

0.3

0.0002

-10

-3

0.4

0.00040-20

RPC 3, Module C-3

0.00060-20

82.6 / 34

0.15

0.2

0.00060-20

χ2 / ndf

0.2

0.001
0.0008×10

47.2 / 25

χ2 / ndf

-10

0

10

20

30
40 50 60
TDC value 106ns/44

0
-20

-10

0

10

20

30 40 50 60
TDC value 106ns/44

Fig. 5. Raw TDC distributions in the two detectors forthe three radial segments. The red distribution shows
muon candidate tracks passing in the vicinity of the
RPC prototype volumes. The muon candidate events
are ﬁt with a Gaussian whose ﬁt parameters are also
displayed.

In addition, an oﬄine time window of 20 ns or lesswill also allow to reduce the cosmic muon backgroundby at least a factor of 5 compared to the present time
gate deﬁned by the muon identiﬁer streamer tube stations.
References
1) S.H. Ahn et al. : Nucl. Instrum. Meth. A 469 (2001).

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Upgrade of PHENIX Muon Tracker Performance and Trigger
Capability for Sea Quark Polarization Measurement at RHIC
I. Nakagawa, T. Mibe,∗1 N. Saito,∗1 I. Ichikawa,∗2 K. Karatsu,∗2 T. Murakami,∗2 K. Nakamura,∗2
R. Sameshima,∗2 Y. Fukao, Y. Ikeda,∗3 J. Murata,∗3 N. Ogawa,∗3 K. Ninomiya,∗3 J. Onishi,∗3 and S. Hirota,∗4[nucleon spin, W-boson, polarized parton distribution, Electronics, trigger]
Several decades have passed since the parityviolating production of the W boson was pointed out tobe the ideal probe for sea quark polarization measurement; this claim is based on almost ﬁxed ﬂavors andfragmentation-function-free interpretation of observed
asymmetry1) . Such measurement has just begun at
RHIC using longitudinally polarized proton beams at
a collision energy of 500 GeV. The W program is thehighlight of the RHIC spin project, which will continue
over the next 5 years; thus, the following projects havebeen proposed to upgrade the PHENIX muon arms inorder to carry out the rare probe measurement underconditions in wihch the background rate is high.




 

















Fig. 1. Installation schedule of PHENIX muon arm upgrade projects. Year in solid square is the scheduledyear of installation.

New front-end electronics (MuTRG-ADTX) boards
were developed and produced to add the trigger
capability to existing PHENIX muon tracker (MuTr)
detectors. The installation in the North muon arm
was completed during the 2008 shutdown period; backend electronics (MuTRG-MRG and MuTRG-DCMIF)
boards5) that serve as an interface between MuTRGADTX and local-level-one (LL1) trigger boards anddata collection modules (DCM) were also installed.
The newly installed trigger electronics chain was commissioned during the engineering run of the ﬁrst 500
3)

∗1
∗2
∗3
∗4

KEK, Tsukuba, Ibaraki, 305-08011 Japan
Kyoto University, Kitashirakawa-Oiwakecho, Kyoto, 6068502 Japan
Rikkyo University, Rikkyo, 3-34-1, Nishi-Ikebukuro, Tokyo,
171-8501 Japan
University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 1130033 Japan- 75 -

GeV polarized proton-proton collision in Run9. The
observed performance has been discussed elsewhere
6,7). The installation of MuTRG-ADTX boards in theSouth muon arm began during the shutdown periodthat followed Run09 and was completed by the end of
2009. These newly installed boards were commissioned
along with Au-Au beams in Run10.
As a result of the project being carried out to upgrade the PHENIX muon arms, the performance ofthe muon detection system will be improved as shownin Fig.1. Another project aimed at upgrading; Resistive Plate Chambers2) production is also being carriedout. The additional hadron absorbers will be installedin Run11, where the ﬁrst production run of polarized
proton-proton collision at 500 GeV is scheduled. Thus,
trigger upgrade projects are running on schedule. Efforts to improve the performance of existing detectors
are also underway. The momentum resolution of MuTr
is a major concern since only resolutions that are lower
than its intrinsic resolution (100µm) by a factor of 2
- 3 have been demonstrated in the past. It has been
proposed that the motion of MuTr chambers on a daily
basis deteriorates the alignment precision. The relativealignment between MuTr chambers is carried out using straight particle trajectories with magnet ﬁeld oﬀ
of MuTr. We observed chamber movement of the orderof 100 µm over the course of a few months during Run9by using an optical alignment system (OASys) implemented in MuTr chamber frames. The OASys consistsof light sources, lenses, and CCD cameras attached tochambers in Station1, Station2, and Station3, respectively, and it tracks the relative motion of the chambers
by continuously monitoring the light spot in the CCD
camera8) . The chamber displacement predicted by the
OASys can be veriﬁed by the zero ﬁeld data that are
obtained at intervals of months. This consistency analysis is now in progress.
References
1) C. Burrell and J. Soﬀer, Phys. Lett. B314, 132 (1993).
2) CDR for a Fast Muon Trigger (2007).
3) TDR on Ampliﬁer-Discriminator board and Data
Transfer board for the MuTr FEE upgrade (2008).
4) Y. Fukao et. al., RIKEN Accel. Prog. Rep. 42 (2009).
5) T. Mibe et. al. RIKEN Accel. Prog. Rep. 42 (2009).
6) Y. Fukaoet. al., RIKEN Accel. Prog. Rep. 43 (2010).
7) K. Nakamura et. al., RIKEN Accel. Prog. Rep. 43(2010).
8) H. Akikawa et. al., NIM A499 537 (2003).

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Performance evaluation of MuTRG
for upgrading PHENIX muon trigger
Y. Fukao for the PHENIX MuTr FEE Upgrade Group[nucleon spin, W boson, polarized parton distribution, electronics, trigger]a)Sagitta is deﬁned as the distance between a hit strip in the
MuTr 2nd station and the linearly interpolated positions of
hit strips in the 1st and 3rd station. Hits are required ina strip at the 2nd station on the linear interpolation when∆s = 0. Hits are required in ±1 strips in the 2nd station
around the linear interpolation when ∆s ≤ 1.

- 76 -

Efficiency

MuTRG Efficiency

1
0.8
0.6
0.4

40 mV, w/o clustering, s

0.2

1

40 mV, w/o clustering, s = 0

0 0

10

20

30

40
50
Track Momentum (GeV)

Fig. 1. Eﬃciency of MuTRG as a function of track momentum. A threshold voltage of 40 mV is applied andclustering is not applied. The black closed circles represent the eﬃciencies when ∆s ≤ 1 and those with red
open circles represent the eﬃciencies when ∆s = 0.
MuTRG performance at 3­MHz collisions

Efficiency at Plateau

The PHENIX experiment aims to directly probe thecontribution of sea quarks to proton spin by performing measurements of single helicity asymmetry in W
boson production. In order to record the W production events eﬀ ectively, we are developing a new trigger
system for the PHENIX muon arm.1) The trigger is designed to sort out events with high momentum tracks,
which are expected to be muons resulting from W decays, by performing rough momentum measurements
online. An overview of the trigger system is provided
elsewhere.2) In 2008, additional electronic component(MuTRG) were installed in the north PHENIX muontrackers (MuTr) to provide readouts of fast signals to
the trigger. The MuTRG was commissioned in the2009 run with the ﬁ rst polarized pp collisions at thecenter-of-mass energy of 500 GeV. This paper describes
the preliminary results of the MuTRG commissioning
tests. Related articles are provided in this reports.3,4)
The MuTRG has several optional parameters suchas the threshold of the deposit charge in MuTr, clustering, and sagitta acceptance ∆s a) that can be adjusted to ensure optimal performance. Figure 1 shows
MuTRG eﬃciency as a function of particle momentum measured by MuTr. The eﬃciency achieved at
the plateau is ∼ 0.9. The turn-on point of the trigger is improved from 2.0 GeV/c to 12.2 GeV/c when∆s = 0 and to 8.5 GeV/c when ∆s ≤ 1. Figure 2
shows the relation between the eﬃciency at the plateau
and the trigger rejection power. The rejection power
is deﬁ ned as the number of collisions divided by the
number of events accepted by the MuTRG. Althoughtight cuts improve the rejection power, they decrease
the eﬃciency.
The installation of the MuTRG in the south muonarm was completed after the 2009 run and its commissioning is ongoing in the 2010 run with heavy-ion
beams. The signal from MuTRG is ﬁ nally combinedwith the signal from resistive plate chambers (RPC)
which is another trigger detector. More improvementin the trigger rejection power is expected with the useof RPCs. In the polarized pp physics run to be performed in 2011, it is estimated that a trigger rejection
power of 4500 will be required with a DAQ bandwidthof 2 kHz. A combined analysis of MuTRG and RPC is

1

40 mV

0.9
0.8

100 mV0.7
0.6

w/o clustering, s 1
w/o clustering, s = 0
w/ clustering, s 1

0.5
0.4
0

1000

2000

3000

4000

5000

6000

7000

8000 9000 10000
Rejection Power

Fig. 2. Relation between eﬃciency and rejection power.
The black closed circles and blue closed squares represent the case when ∆s ≤ 1, while the red open circles
represent the case when ∆s = 0. Clustering of hits is
applied in each station in the case represented by theblue closed squares. Threshold voltage of 40 mV and
100 mV is set for the points where the rejection power
is less than and greater than 5000, respectively.

being carried out to evaluate the ﬁ nal performance anddetermine the parameters for optimal performance ofthe MuTRG.
References
1) PHENIX collaboration: Nucl. Instrum. Meth. A 499,
537 (2003).
2) I. Nakagawa et al.: RIKEN Accel. Prog. Rep. 42 (2009).
3) I. Nakagawa et al.: RIKEN Accel. Prog. Rep. 43 (2010).
4) K. Nakamura et al.: RIKEN Accel. Prog. Rep. 43 (2010).

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Measurement of the interference fragmentation function in e+ e−
R. Seidl,∗1 A. Vossen,∗2 M. Grosse-Perdekamp,∗2 A. Ogawa,∗3, M. Leitgab,∗2 and P. Francisconi,∗2[spin dependent fragmentation, transverse spin]

0.20 < z 2 < 0.28
0.4

0.5

0.6

0.7

0.8

0.04
0.02
0
-0.02
-0.04
-0.06
-0.08
-0.1
-0.12
-0.14

0.9
z1

0.04
0.02
0
-0.02
-0.04
-0.06
-0.08
-0.1
-0.12
-0.14

0.28 < z 2 < 0.35
0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9
z1

a12

0.3

a12

0.2

a12

0.25 GeV/c2 < m1 < 2.00 GeV/c 2 , 0.25

0.04
0.02
0
-0.02

-0.1
-0.1
-0.12

0.42 < z 2 < 0.50
0.3

0.4

0.5

0.6

0.7

0.8

0.9
z1

0.50 < z 2 < 0.57
0.2

0.3

0.5

0.6

0.7

0.8

0.9
z1

a12

0.2

0.0
0.04
0.02
0
-0.02
-0.04
-0.06
-0.08
-0.1
-0.12
-0.14

0.04
0.02
0
-0.02
-0.04
-0.06
-0.08
-0.1
-0.12
-0.14

-0.06
-0.08

0.2

0.3

0.4

0.5

0.72 < z 2 < 0.82

-0.12
-0.14
0.6

0.7

0.8

0.9
z1

0.4

0.5

0.6

0.7

0.8

0.9
z1

0.6

0.7

0.8

0.9
z1

0.6

0.7

0.8

0.9
z1

0.57 < z 2 < 0.65
0.2

0.04
0.02
0
-0.02
-0.04
-0.06
-0.08
-0.1
-0.12
-0.14

0
-0.02

0.65 < z 2 < 0.72

0.3

0.3

0.4

0.5

a12

0.04
0.02
0
-0.02
-0.04
-0.06
-0.08
-0.1
-0.12
-0.14

0.35 < z 2 < 0.42
0.2

a12

0.04
0.02
0
-0.02
-0.04
-0.06
-0.08
-0.1
-0.12
-0.14

a12

a12

and the publication of the ﬁnal results is in progress.
We observe large asymmetries which are rising with thefractional energy, as can be seen in Fig. 2. Since theproduct to two interference fragmentation functions ismeasured, the eﬀect of each individual function rises
up to more than 30% at highest z. The asymmetries
are also rising with the invariant mass of the pion pairwhich is not shown here due to space limitations. It
is important to note, that this mass behavior favors
model calculations by Radici9) over those by Jaﬀe8)
which have predicted a sign change a the ρ meson mass.

a12

The interference fragmentation function IFF is achiral-odd fragmentation function suggested by Collins
1)which can act as an analyzer of transverse quark
spin. In contrast to the Collins function4) , previously also measured in e+ e− by us2,3) , the IFF does
not require a transverse momentum dependence andcollinear factorization can be applied. This allows amodel independent extraction of the quark transversity from SIDIS and pp data using the known collinear
evolution5) . Following Boer6) , the measurement relies
on extracting an azimuthal correlation of the planes
spanned by two charge ordered π + π − pairs relative
the reaction plane deﬁned by the incoming leptons andthe formed quark-antiquark pair approximated by thethrust axis. The planes and angular deﬁnitions are
displayed in Fig. 1. The results are obtained froma 672fb−1 data sample that contains 711 × 106 π + π −pairs and was collected near the Υ(4S) resonance, with
the Belle detector at the KEKB asymmetric energye+ e− collider. In events with a clear two-jet like topology as deﬁned by a thrust value larger than 0.8 a π + π −pair is selected in each hemisphere. The azimuthal angular yield of these pairs is then normalized by the average yield and ﬁt by several azimuthal modulations.
The cos(φ1 + φ2 ) modulation (a12 ) is proportional to�the product of the interference function H1 (z, m) on
the quark side times the interference function on theantiquark side, normalized by the corresponding unpolarized functions, where z = Epair /Equark is the fractional energy of the hadron pair and m its invariant
mass. Preliminary results were ﬁrst shown this year7)

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9
z1

0.82 < z 2 < 1.00
0.2

0.3

0.4

0.5

Fig. 2. a12 modulations for the 9 × 9 z1 , z2 binning as afunction of z2 for the z1 bins, where 1, 2 stands for thehemisphere.

The analysis for the extraction of the interferencefunction for other hadron combinations is ongoing.
References

φ2 − π

e−
Ph4
Ph1

Ph3

R1 Ph1 + Ph2

Ph2e+π − φ1Thrust axis n̂

Fig. 1. Azimuthal angle deﬁnitions for φ1 and φ2 as deﬁned
relative to the thrust axis.
∗1
∗2
∗3

Riken BNL Research Center, Upton, USA.
University of Illinois, Urbana Champaign, USA.
Brookhaven National Laboratory, Upton, USA.

- 77 -

1) J. C. Collins, S. F. Heppelmann and G. A. Ladinsky,
Nucl. Phys. B 420, 565 (1994) [arXiv:hep-ph/9305309].
2) R. Seidl et al. [Belle Collaboration], Phys. Rev. Lett. 96(2006) 232002 [arXiv:hep-ex/0507063].
3) R. Seidl et al. [Belle Collaboration], Phys. Rev. D 78,
032011 (2008) [arXiv:0805.2975 [hep-ex]].
4) J. C. Collins, Nucl. Phys. B 396, 161 (1993) [arXiv:hepph/9208213].
5) F. A. Ceccopieri, M. Radici and A. Bacchetta, Phys.
Lett. B 650, 81 (2007) [arXiv:hep-ph/0703265].
6) D. Boer, R. Jakob and M. Radici, Phys. Rev. D 67
(2003) 094003 [arXiv:hep-ph/0302232].
7) A. Vossen, R. Seidl, M. Grosse-Perdekamp, M. Leitgab,
A. Ogawa and K. Boyle, to appear in the proceedings ofthe Dubna Spin workshop 2009, arXiv:0912.0353 [hepex].
8) Jaﬀe, R.L. and Jin, X. and Tang,J.,Phys. Rev.
Lett.80,1166, (1998)
9) Bacchetta,A. and Radici,M.,Phys. Rev.,D74,114007(2006)

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Precision Measurements of Charged Hadron Multiplicities in e+ e−
Annihilation at BELLE
M. Leitgab,∗1 M. Grosse Perdekamp,∗1 R. Seidl,∗2 A. Ogawa,∗3 A. Vossen,∗1 K. Boyle∗2 and P. Francisconi∗1

This paper summarizes the status of precision measurements of π +,− and K +,− (in the following, resolving all particle charges is implied) multiplicities in
e+ e− annihilation at a center of mass energy of 10.52
GeV at the BELLE experiment at KEK, Japan1) . The
hadron multiplicities are measured as a function ofz which is the hadron energy relative to half of thecenter-of-mass energy in electron-positron annihilation
into quark-antiquark pairs. The measured multiplicity
distributions are corrected for particle misidentification and acceptance effects.
2

Motivation

Multiplicity measurements at Belle are motivatedby two recent studies on the extraction of unpolarizedfragmentation functions2),3) . Fragmentation functions
describe hadron production from a final-state quark or
gluon in processes such as hadron collisions, electronpositron annihilation and deep inelastic scattering of
leptons on protons or nuclei. The present measurement is intended to provide high precision datasets
as an input to the extraction of fragmentation functions, and thereby significantly lower the uncertainties
of these. Precise knowledge of fragmentation functions
is required for the extraction of the gluon helicity distribution from spin asymmetries measured in hadroncollisions at the Relativistic Heavy Ion Collider4) .
3

Measurement Status and Outlook

For charged hadrons, experimental particle yields
need to be corrected for particle misidentification. In
an analysis test-run this correction has been found tochange the measured charged particle distributions at
the order of 5 to 10% for pions and 10 to 35% for kaons.
The correction is performed through an unfolding technique based on inverse 4x4 particle identification (PID)
probability matrices. To not rely on the GEANTbased5) Monte Carlo modelling of the BELLE PID
performance, the elements of the probability matrices are obtained from reconstructing unstable particles
in experimental data with purely kinematical means,forming samples of tracks with known ’real/physical’
∗1

∗2
∗3

University of Illinois at Urbana-Champaign (UIUC), USA
RIKEN BNL Research Center (RBRC), USA
Brookhaven National Laboratory (BNL), USA- 78 -

6000
6000
5000
5000
4000
4000

total

900

f

800

bg(m - mD0)

(m - mD0)
D*

D*

700
600
500

3000
3000

400
300

2000
2000

200

1000
1000
0
0.14
0
0.14

D*

total

f total(mD* - mD0)
f (mD* - mD0)
bg(mD* - mD0)
bg(mD* - mD0)

7000
7000

N(m -mD0)

Measurement DescriptionD*

1

N(m -m-m0)0)N(mD* DD[Precision hadron multiplicities, fragmentation functions, BELLE, particle identification]

100

0.142
0.142

0.144
0.144

0.146
0.146

0.148
0.148

a)

0.15
0.15

0.152
0.152

0.154
0.154

m
mD*D*--m
mDD00[GeV/c^2][GeV/c^2]

0.14

0.142

0.144

0.146

0.148

0.15

0.152

0.154

mD* - mD0 [GeV/c^2]b)Fig. 1. Fits of experimental data invariant mass distributions on a reconstructed sample of the decay D ∗ →π(D 0 → Kπ). Figures a) and b) show distributions
without and with an additional PID likelihood cut toselect particles of species j = π. Extracting the PID
probability p(K − →π− ) from the ratio of the hatched areas yields 0.111 ± 0.004 for negatively charged kaons
with laboratory frame momentum in [1.4; 1.6] GeV/cand laboratory azimuthal angle θ in [77.9; 89.0] degrees.

species i = {e/µ, π, K, p}. PID probabilities p(i→j)
can be calculated by additionally applying PID likelihood cuts to select particles of species j from thereconstructed samples and forming ratios of the yields
obtained with and without PID cuts. Decays of D∗ , Λ
and J/ψ particles are analyzed. Figure 1 shows fits ofexperimental data distributions from the reconstructeddecay D∗ → π(D0 → Kπ) which allow to extract the
PID probability p(K − →π− ) .
Eventually, the measurement of hadron multiplicities against their normalized energy z will be performed from about 0.2 to close to 1.0 in z. The systematic uncertainty analysis for PID, momentum smearing
and acceptance effects will be finalized. The leading
uncertainty is expected to arise from the systematic
uncertainties connected with the PID correction. The
overall systematic uncertainties are expected to remain
below 3% (5%) for π (K) spectra for z < 0.6, and toincrease with z up to 5% (17%) for π (K) spectra,
respectively.
References
1) A. Abashian et al.; Nucl. Instrum. Methods A 479,
(2002), pp. 117-232.
2) M. Hirai, S. Kumano, T.-H. Nagai, K. Sudoh; Phys.
Rev. D 75, 114010 (2007).
3) D. de Florian, R. Sassot, M. Stratmann; Phys. Rev. D
75, 094009 (2007).
4) A. Adare et al.; Phys. Rev. Lett. 103, 012003 (2009).
5) Geant 4 Collaboration; Nucl. Instrum. Methods A 506,
(2003), pp. 250-303.

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Photoproduction of Λ(1405) and Σ0 (1385) on the proton at Eγ =1.5-3.0 GeV at SPring-8/LEPS
Y. Nakatsugawa for LEPS collaboration[photoproduction, Λ(1405)]
In a quark model, Λ(1405) is a p-wave q3 baryon.
However, it is also suggested that Λ(1405) has a nonq3 structure such as a meson-baryon molecular state.
In some theoretical studies, chiral Lagrangian and coupled unitary model were used to predict the line shapeof Λ(1405) as πΣ0 and KN.1) The two-pole structure ofΛ(1405) was also suggested.2) The contribution of thesecond pole might be extracted by treating K and K∗
exchange reaction separately, and information about
exchanged particles can be obtained from photon beam
asymmetry. Therefore, it is of interest to obtain themass spectrum of Λ(1405) and determine the photon
beam asymmetry. On the other hand, it has been
firmly established that Σ0 (1385) is a q3 baryon. The
difference between the internal structures of Λ(1405)
and Σ0 (1385) may appear in the photoproduction crosssections and/or photon beam asymmetries. Recently,
differential cross sections for γp → K+ Λ(1405) and γp→ K+ Σ0 (1385) reactions were measured by LEPS collaboration.3) However, the statistics were limited. A
new experiment was carried out at SPring-8/LEPS using a liquid hydrogen target and a linearly polarized
photon beam. In order to detect the decay products ofhadrons, a time projection chamber (TPC) surrounding the target was used along with the LEPS spectrometer. Detailed information on the differential cross sections of γp → K+ Λ(1405) and γp → K+ Σ0 (1385) andthe line shapes of Λ(1405) will be obtained from newdata. The photon beam asymmetries will be also investigated.
The analysis of new data is still underway. The
present status of the analysis and very preliminary results are reported in this article.
In order to obtain the spectra of Λ(1405) andΣ0 (1385) separately, we selected the following two reactions and imposed certain cut conditions:(1) γp → K+ Σ0 (1385) →K+ Λπ 0 →K+ pπ − π 0(2) γp → K+ Λ(1405) →K+ Σ± π ∓ →K+ nπ + π −The spectrum of Σ0 (1385) was obtained by observing reaction (1) under the following cut conditions: (i)K+ was detected in the forward spectrometer, (ii) a
proton and a π − were detected in the TPC, and (iii)a Λ(1116) was identified on the basis of the invariant
mass of pπ − . In Fig.1(a), a bump corresponding toΣ0 (1385) can be seen. Owing to isospin conservation,
Λ(1405) does not decay into Λπ 0 , hence the yield ofΣ0 (1385) can be estimated from its decay branchingratios. The spectrum of Λ(1405) was obtained by observing reaction (2) under the following cut conditions:- 79 -

Fig. 1. Missing mass spectrum of γp → K+ X : (a) Selection
cuts (i), (ii), and (iii) were applied. (b) Selection cuts(iv), (v), and (vi) were applied.

(iv) K+ was detected in the forward spectrometer, (v)a π + and a π − were detected in the TPC, and (vi) a
neutron was identified on the basis of the missing massof γp → K+ π + π − X . The bump around 1.4 GeV in Fig.
1(b) corresponds to Λ(1405). Since Σ0 (1385) can decay
into Σπ, the contribution of the contamination should
be subtracted from the spectrum in order to estimate
the yield of Λ(1405). However, this has not yet been
done because the acceptance calculation is yet to becompleted. In the future, the differential cross sectionsof γp → K+ Σ0 (1385) and γp → K+ Λ(1405) will be determined, and the Eγ dependence of the cross sections
and line shape of Λ(1405) will be investigated. In thisstudy, photon beam asymmetries were also measuredfor γp → K+ Σ0 (1385) and γp → K+ Λ(1405) reactions.
The error is large because only one quarter of all data
was used for the analysis of photon beam asymmetries.
More precise results will be reported as final results.
References
1) J. C. Nacher, E. Oset, H. Toki, and A, Ramos: Phys.
Lett. B 455, 55 (1999).
2) D. Jido, J. A. Oller, E. Oset, A. Ramos, and U.-G.
Meissner: Nucl. Phys. A 755, 669 (2005).
3) M. Niiyama et al.: Phys. Rev. C 78, 035202(2008).

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

E906 Drell-Yan experiment at Fermilab
Y. Goto, Y. Fukao, K. Imai,∗1 Y. Miyachi,∗2 S. Miyasaka,∗3 S. Mizugashira,∗3 T. Nagae,∗1 K. Nakano, S.
Sawada,∗4 T.-A. Shibata,∗3 A. Taketani, and M. Togawa for the Fermilab E906/SeaQuest Collaboration

∗1

∗2
∗3
∗4

Kyoto University
Yamagata University
Tokyo Institute of Technology
KEK- 80 -

References
1) P. Amaudruz et al.: Phys. Rev. Lett. 66, 2712 (1991):
M. Arneodo et al.: Phys. Rev. D 50, R1 (1994).
2) R. S. Towell et al.: Phys. Rev. D 64, 052002 (2001).
3) J. Pumplin et al.: JHEP 0207, 012 (2002).
4) J. J. Aubert et al.: Phys. Lett. B 123, 275 (1983).
5) D. M. Alde et al.: Phys. Rev. Lett. 64, 2479 (1990).
6) K. Nakano et al.: RIKEN. Accel. Prog. Rep. 43, xxx(2010).

2.25
E906 18
3.4 10 POT

2

E866

1.75

NA51

1.5
-

x1 x2assuming that x1  x2 and the uū annihilation term
is dominant; x1 and x2 are the momentum fractionsof a quark or an antiquark in the beam proton andtarget proton, respectively. The Fermilab E866 exper¯ ratio
iment determined the x-dependence of the d/ūin this way,2) as shown in Fig.1, with an 800 GeV/cproton beam from the Fermilab Tevatron incident onhydrogen and deuterium targets. At moderate valuesof x, the data show an excess of d¯ over ū by more than
60%, but this excess disappears and the antiquark distributions appear to be symmetric at high x values.
The ratio of d¯ to ū quarks determines whether there
is competition between perturbative QCD gluon dissociation and non-perturbative contributions. Calculations have shown that perturbative processes create
flavor-symmetric antiquark distributions, while nonperturbative approaches such as the use of meson cloudmodels, chiral perturbation theory, or instantons can
explain a large asymmetry, but not the return to symmetric distributions seen as x → 0.3. None of the¯ as shown bymodels predicts an excess of ū over d,the CTEQ6 global parton distribution fit3) in Fig.1.
Many of these models relate the flavor asymmetry to
the intrinsic spin carried by the antiquark. The Fermilab E906 experiment will use a 120 GeV proton beam
extracted from the Fermilab Main Injector to study
flavor symmetry violation at high values of x > 0.45.
The E906 experiment will also measure the DrellYan yields from nuclear targets. The nuclear target
data can be used to constrain partonic energy loss incold nuclear matter. This is a necessary step in understanding models that also predict partonic energy
loss in the hot nuclear matter used at the RHIC. In
addition, the data will allow us to observe modifications of the antiquark distributions in nuclei relative
to the nucleon. The distribution of partons in a freenucleon is different from that in a bound nucleon, an

effect first discovered by the European Muon Collaboration from muon DIS experiments in 1983.4) Althoughmany models of nuclear binding involve virtual mesonexchange, which modifies the antiquark distributionsof the nuclei, present data suggest that the antiquark
distributions are not modified.5) The E906 experimentwill either observe the modifications predicted by thesemodels or invalidate many of the models.
The collaboration expects to begin data collection in
the summer of 2010. Japanese groups (RIKEN, KEK,
Kyoto Univ., Tokyo Tech., and Yamagata Univ.) arein charge of one of the drift-chamber stations. The
station is currently under construction in Japan, andit will be shipped to Fermilab in the spring of 2010. 6)

d /u

Flavor symmetry violation of antiquark distributions
was first observed by the New Muon Collaboration inmuon deep inelastic scattering (DIS) experiments.1)
The Drell-Yan process provides a complementary way
to select only the antiquark distributions and it is an
ideal process for flavor asymmetry measurement. In
leading order, the ratio of the proton-proton to protondeuterium Drell-Yan yields can be expressed as¯ 2) 
1d(xσpd 
=1+,
2σpp 
2ū(x2 )

CTEQ6

1.25
1
0.75
0.5
0.25
0

E866 Systematic Error
0

0.1

0.2

0.3
x

0.4

0.5

0.6

¯ as determined in the E866 (blueFig. 1. The ratio d/ūsquares) and NA51 (pink triangle) experiments. The¯ ratio and uncentral curve in the band shows the d/ūcertainty in the CTEQ6 fit, which includes the E866
data. The red circles represent the expected statisticaluncertainties in the E906 data. The expected systematic uncertainty is approximately 1%.

1

RIKEN Accel. Prog. Rep. 43 (2010)

A proposal to study medium mass modiﬁcation of ϕ-mesons using
ϕ-meson bound state in nucleus†
H. Ohnishi∗1 and K. Tsukada∗1[Spontaneous breaking of Chiral symmetry, meson bound state]
A proton is composed of two ”Up” quarks and one”Down” quark and has a mass of 938 MeV/c2 . On
the other hand, the mass of bear quark, i.e. ”Up” and”Down” quark is known to be a few MeV/c2 . Therefore, the contribution of the constituent quarks to themass of a proton is very less. We must now identify aprocess by which more than 90 % of the proton masscan be generated from vacuum. This mechanism is
now known to involve spontaneous breaking of chiralsymmetry, and it generates a non-zero quark antiquark
condensate ⟨qq⟩ in vacuum. This quark-antiquark condensate ⟨qq⟩ is the major contributor to the mass of
low-lying hadrons such as protons, neutrons and pions.
In the theoretical framework, the quark-antiquark condensate ⟨qq⟩ (chiral order parameter) is a function oftemperature and chemical potential (density).
In this study we focus on the ϕ-mesons in a nucleus.
According to an experimental study of the invariant
mass spectra of ϕ-mesons in the pA reaction, the ϕmeson mass shift in medium heavy nuclei (Cu) is approximately about 3.4% and the natural width broadening of Γϕ /Γϕfree is ≈ 3.61) . We are attending to understand the meaning of the mass reduction of 3.4%(= 35 MeV/c2 ) observed for the ϕ-mesons in a nucleus. A possible clue can be obtained from the kaon
sin nucleus. Reference2) shows that the mass of theK− will be reduced in nuclear matter owing to thestrong attractive potential between the K− and thenucleon. This theoretical prediction indicates that themass reduction of ϕ-mesons in a nucleus is directly
related to the possible existence of an attractive potential between the ϕ meson and the nucleus. The
depth of the potential well is expected to be on thesame order as measured mass reduction. Therefore,
we adopted an experimental approach to measure theϕ-meson properties in nuclear media, by studying formation of a ϕ-meson bound state. The most interesting ϕ-meson formation channel that could be ideal
for the formation of a ϕ-meson bound state is thep + p → ϕ + ϕ channel. One striking outcome of thisreaction is the rather large ϕϕ production cross section
near the production threshold (∼0.9 GeV/c), namely,
an incident p momentum of 1.3 ∼ 1.4 GeV/c. The
most distinguishable feature of this reaction channel is
its fully background-free nature. The yield of the processes, ϕK + K − and K + K − K + K − , are considerably†∗1

Condensed from the experimental proposal submitted to JPARC (P29)
RIKEN Nishina Center- 81 -

smaller than those of the double ϕ production channel when the incident p momentum is selected below
1.4 GeV/c3) . Another unique feature of this reactionis that all the particles we observe, including thoseemitted in the forward ϕ → K + K − decay, are labeledwith strangeness so that they be clearly distinguishfrom the particles formed in other processes. This ensures that the process is free process of any accidental background. In addition to strangeness tagging by
forward-going kaons, the background can be considerably reduced in missing-mass spectra by using a combination of (p, ϕ) spectroscopy together measurements
and K + Λ tagging for this reaction; this ensures thatstrange quarks are actually embedded in the nucleus.
From the missing mass and invariant mass study of the
sub-threshold energy region, one can independently deduce the mass-shift information. A systematic study ofseveral nuclear targets will help in the unique, deﬁnitive, and precise determination of the in-medium mass
modiﬁcation of the vector meson ϕ(ss). Despite of the
low cross section of the p(p, ϕ)ϕ reaction, we can expect an excellent ground-state-formation rate of 240
per month when using a p beam with an intensity of
2 × 106 particles per spill on a carbon target. The conceptual design for the spectrometer be used in (p, ϕ)
spectroscopy is shown in Figure 1.

Fig. 1. conceptual design for the spectrometer.

The experimental proposal has been submitted to
the J-PARC Program Advisory Committee, and detailstatus and R&D activities for the detector are currently underway.
References
1) R. Muto et al.; Phys. Rev. Lett. 98,042501 (2007).
2) T. Waas et al; Nucl.Phys.A617, 449(1997)
3) C. Evangelista et al.; Phys. Rev. D57 5370(1996).

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Simulation study for the multiplicity Measurement in the
Proton-Proton Collisions at the LHC†
S. Sano,∗1 H. Hamagaki,∗1 T. Gunji,∗1 C. Garabatos2 M. Ivanov2 and J. Wiechula2[Multiplicity, Color Glass Condensate (CGC), LHC]×Cp T cut (η  )(1)where the integration is executed for the available region of pT . C(η  , pT ) is the correction factor obtainedN(η,pT ). Nacc (η, pT ) and Ngen (η, pT )as C(η, pT ) = Ngenacc (η,pT )are the numbers of charged particles accepted and generated, respectively. Cp T cut (η  ) is the correction factor due to the pT cutoff. In this analysis, particles of
pT < 0.3 GeV are cut.
Figure 1 shows the projections of 1/C(η, pT ) to η andpT , which corresponds to the reconstruction efficiencyof the TPC for charged particles, where any feed-down∗1∗2

Center for Nuclear Study (CNS), University of Tokyo, Japan
Gesellschaft fur Schwerionenforschung (GSI), Germany- 82 -

1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0 −1
10

efficiency

1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0 −1.5efficiency

Parton density grows rapidly with decrease of fractional momentum x, but eventually tends to saturate,
as a consequence of self-interaction of gluons, which
is an intrinsic property of non-Abelian gauge theory.
Such saturated state may be described with a classicalfield theory such as Color Glass Condensate (CGC)1,2) .
An investigation of gluon saturation is important to decide the initial condition for high-energy heavy-ion collisions. CGC effects may be seen even at mid-rapidity
through the measurement of pseudo-rapidity distribu√
tion of charged particles dN/dη in sN N = 10 TeV√
p + p collisions and sN N = 5.5 TeV Pb+Pb collisions at LHC3) . This report describes the status of apreparation for the measurement of dN/dη.
Simulation study for dN/dη was done, and the correction factor was evaluated. dN/dη can be measured
using the ALICE Time Projection Chamber (TPC),
which is the main detector for tracking in the central
barrel4) . AliRoot, the ALICE software package, canprovide event generation, simulation of the detector response, and reconstruction. The reconstructed tracks
are recorded as ESD (Event Summary Data) tracks
which have labels corresponding to the ID number ofgenerated particles. Therefore, the reconstruction efficiency can be evaluated from the comparison between
generated particles (MC particles) and ESD tracks using labels. PYTHIA 6 event generator was adopted,
and√ 277,500 events of minimum-bias p + p collisions at
s = 10 TeV were used.
The detection efficiency is assumed to depend on
pseudo-rapidity, and transverse momentum. Therefore, dN/dη is calculated as
 pT 2
 dN 
dN|η=η =C(η  , pT )dpTdη
dpT dη ESD
pT 1−1 −0.5

0

0.5

1

1.5

η

1

10

p (GeV)T

Fig. 1. The reconstruction efficiencies for charged particles
as a function of η and pT . These are the projections of
1/C(η, pT ) to η and pT .

Fig. 2. Comparison of dN/dη between MC prediction and
ESD. Circles show the result of ESD analysis andsquares show the plots for only primary particles passed
the cut of ESD analysis.

correction is not applied.
Figure 2 shows the comparison of dN/dη between
MC prediction (lines) and this analysis with the correction according to Eq. 1. (circles). The result of
this analysis (circles) includes both primary particles
and secondary particles which passed the cut of thisanalysis. Squares in Fig. 2 show the plots for only
primary particles. The ratio of the true primary particles to ESD plots (circles) of Fig. 2 is about 82±2%
at |η| < 0.5.
References
1) L.V. Gribov, E.M. Levin, M.G. Ryskin, Phys. Rep.100(1983) 1.
2) L. McLerran, R. Venugopalan, Phys. Rev. D49 (1994)
2233.
3) D. Kharzeev, E. Levin, M. Nardi, Nucl Phys A 747(2005) 609.
4) ALICE Collaboration. ”ALICE TPC Technical Design
Report”. CERN/LHCC 2000-001.

1

4.

Hadron Physics (Theory)

RIKEN Accel. Prog. Rep. 43 (2010)

Nuclear Force from String Theory†
K. Hashimoto,∗1 T. Sakai,∗2 and S. Sugimoto∗3[Nuclear force, Superstring theory]
We compute nuclear force in a holographic model of
QCD on the basis of a D4-D8 brane conﬁguration in
type IIA string theory. Repulsive core of nucleons isquite important in nuclear physics, but its origin has
not been well-understood in strongly-coupled QCD.
We ﬁnd that string theory via gauge/string duality
deduces this repulsive core at short distance between
nucleons. Since baryons in the model are realized assolitons given by Yang-Mills instanton conﬁguration on
ﬂavor D8-branes, ADHM construction of two instantons probes well the nucleon interaction at short scale,
which provides the nuclear force quantitatively. We
obtain, as well as a tensor force, a central force whichis strongly repulsive as suggested in experiments andlattice results. In particular, the nucleon-nucleon potential V (r) (as a function of the distance) scales as
r−2 , which is peculiar to the holographic model. We
compare our results with one-boson exchange modelusing the nucleon-nucleon-meson coupling obtained in
our previous paper2) .
Nuclear force, the force between nucleons, exhibitsa repulsive core of nucleons at short distances. This
repulsive core is quite important for large varieties ofphysics of nuclei and nuclear matter. For example, thewell-known presence of nuclear saturation density is essentially due to this repulsive core. However, from theviewpoint of strongly coupled QCD, the physical originof this repulsive core has not been well-understood. In
spite of the long history of the problem, it was rather
recent that lattice QCD could reach the problem, andof course any understanding of it based on analytic
computations is quite helpful for revealing basic nature of nuclear and hadron physics.
Recent rapid progress in applying gauge/string duality to QCD, holographic QCD, is really surprising. Now it has been made possible to compute various observables in hadron physics such as spectraof mesons/baryons/glueballs and interactions among
them. Although most of the works rely on the supergravity approximation that works for large Nc andlarge ’t Hooft coupling λ, it turned out that the holographic QCD reproduces quite well the properties ofhadrons not only qualitatively but also quantitatively.
We apply this gauge/string duality to the problem of
nuclear force. In our previous paper2) , we computed
†
∗1
∗2
∗3

Condensed from the article in Prog. Theor. Phys. 122, 427(2009)
Theoretical Physics Laboratory, RIKEN
Department of Physics, Ibaraki University
Institute for the Physics and Mathematics of the Universe,
University of Tokyo- 83 -

nucleon-nucleon-meson couplings, by using the holographic QCD based on a D4-D8 brane conﬁguration
in type IIA string theory1) , which incorporates chiralquark dynamics. This amounts in principle to computing the large distance behavior of nuclear force, as
the potential between two nucleons can be understoodas exchange of mesons among them. In this paper,
we make one step further: by directly solving the twonucleon system in the D4-D8 model of the holographic
QCD, we ﬁnd shorter distance scale of the nuclear
force.
In fact, we ﬁnd the repulsive core of nucleons. Our
computation shows the following result for the central
and tensor forces,
27 32 a a b b Nc 1
+ (I1 I2 )(J1 J2 ), (1)VC (|r|) = π
25
λ |r|28π a a Nc 1
I I
.
(2)
VT (|r|) =5 1 2 λ |r|2
This is, ﬁrst of all, repulsive, and second, has 1/r2
dependence. The r-dependence is peculiar to the fourdimensional space, not the three-dimensional harmonic
potential. The appearance of the 1/r2 potential isdue to the extra holographic dimension, thus typicalin holographic description. Physically speaking, theKaluza-Klein summation of all the meson states in thetower produces this new behavior.
The main reason why the force is repulsive is as follows. In holographic QCD, global symmetries of QCD
are upgraded to local ones via the correspondence, andso baryon number carried by the baryon is coupled to
local gauge ﬁelds in higher dimensions. This produces
the repulsive force. The Kaluza-Klein decompositionof the higher-dimensional gauge ﬁelds provides a mass
tower starting with ω meson as the lightest vector meson1) , and so, our computation shows that the repulsive force is partly due to the ω meson exchange. Not
only the ω meson but also the whole massive mesons
participate in the nuclear force, and resultantly, thenucleon-nucleon potential becomes 1/r2 .
It would be very interesting if our results can beconsistently compared with lattice results or empirically known potentials used in “ab-initio” calculationsof nuclear spectra.
References
1) T. Sakai and S. Sugimoto, Prog. Theor. Phys. 113, 843(2005), Prog. Theor. Phys. 114, 1083 (2005).
2) K. Hashimoto, T. Sakai and S. Sugimoto, Prog. Theor.
Phys. 120, 1093 (2008).

RIKEN Accel. Prog. Rep. 43 (2010)

Quark fragmentation functions in the NJL-jet model†
W. Bentz,∗1 T. Ito,∗1 I. C. Cloët,∗2 A. W. Thomas,∗3 and K. Yazaki∗4��
QUARK FRAGMENTATION FUNCTIONS, Semi-inclusive pion production, Deep inelastic
scattering

Quark distribution and fragmentation functions are
the basic nonperturbative ingredients for a QCD-based
analysis of hard scattering processes. In this paper weshow the results of recent calculations of fragmentation
functions in the NJL-jet model1) .
The spin-independent fragmentation function for theprocess q → h is deﬁned by�dω − ip− ω− /z �zˆDqh (z) =en122π× �p(h), pn |ψ(0)|0� γ + �0|ψ(ω − )|p(h), pn �.

z Duπ

+

rules, it is necessary to take into account the possibility that the fragmenting quark produces a cascade ofmesons. In order to describe these multi-fragmentation
processes, we use the ideas of the quark jet model of
Field and Feynman2) . Assuming that the fragmenting
quark can produce a maximum of N mesons, we makea product ansatz to express the total fragmentation
function as a product of N elementary splitting functions. Because only in the limit N → ∞ it becomes
possible to transfer 100% of the initial quark momentum and isospin to the mesons, we take this limit in
the ﬁnal results. The details of this product ansatz can
The ﬁeld operators refer to a quark of ﬂavour q, thebe found in Ref.1) .
symbol p(h) refers to a hadron h with momentum p,
In the numerical calculations we take into accountand pn labels the spectator state. The light-cone comthe
fragmentation to pions only. The results for theponents of√a 4-vector aµ are deﬁned by a± = a∓ =“favored”
fragmentation process u → π + are shown in(a0 ± a3 )/ 2. From this deﬁnition one can derive theFig. 1. This ﬁgure demonstrates the tremendous enexpression
hancement of the fragmentation function arising from�†� �k(α)|a (p)ah (p)|k(α)� the cascade-type multi-fragmentation processes. In or1hDqh (z) dz = dp− d2 p⊥, der to improve the agreement with the empirical frag6
�k(α)|k(α)�
αmentation function, one should perform the Q2 evolution in next-to-leading order, and include the eﬀects of
where the creation and annihilation operators refer tofragmentation processes to other hadrons, mainly thethe hadron h, k(α) labels a quark state of ﬂavour q with
nucleons, antinucleons and kaons.
momentum k and spin-color α, and p− = zk− for someﬁxed k− > 0. The above result can be interpreted as
NJL-elementary
1.2
NJL-jet (Q20 = 0.18 GeV2 )the light-cone momentum distribution of the hadron h
NJL-jet (Q2 = 4 GeV2 )1.0
in the quark q.
Empirical (Q2 = 4 GeV2 )The momentum and isospin sum rules obtained from0.8
the above formula are
0.6
�� 1
�� 1
0.4
dz z Dqh (z) = 1 ,dz th Dqh (z) = tq .
LO
h

0

h

0

0.2

The condition which lies at the basis of these sum rules
is that the initial quark state is an eigenstate of the
momentum and isospin operators, expressed solely interms of hadrons. Their physical content is that 100%of the initial quark light-cone momentum (k− ) andisospin (tq ) are transferred to the hadrons. (Note thatthe deﬁnition of the fragmentation function implies anaverage over the isospin of the soft quark remainder ofa fragmentation chain.)In order to satisfy the momentum and isospin sum
†

∗1
∗2
∗3
∗4

Condensed from an article by T. Ito, W. Bentz, I.C. Cloët,
A.W. Thomas and K. Yazaki, Phys. Rev. D 80 (2009)
074008.
Department of Physics, Tokai University, Kanagawa, Japan
Department of Physics, University of Washington, Seattle,
WA, U.S.A.
University of Adelaide, Adelaide, Australia
Radiation Laboratory, RIKEN, Saitama, Japan- 84 -

0
0

0.2

0.4

z

0.6

0.8

1.0

+

Fig. 1. Fragmentation function zDuπ (z). The dash-dottedline is the elementary fragmentation function, and thedotted line is the full fragmentation function in the
NJL-jet model. The solid line is the result after LO evolution to Q2 = 4 GeV2 , and the dashed line is the empirical NLO result of Ref.3) , evolved to Q2 = 4 GeV2 .

References
1) T. Ito, W. Bentz, I.C. Cloët, A.W. Thomas, K. Yazaki,
Phys. Rev. D 80, 074008 (2009).
2) R. D. Field and R. P. Feynman, Phys. Rev. D 15, 2590
(1977).
3) M. Hirai, S. Kumano, T. H. Nagai and K. Sudoh, Phys.
Rev. D 75, 094009 (2007).

RIKEN Accel. Prog. Rep. 43 (2010)

Nucleon structure functions in 2+1-ﬂavor dynamical DWF QCD†
S. Ohta,∗1∗2∗3 for RBC and UKQCD Collaborations[Quantum Chromodynamics, Hadron Physics, Nucleon Structure]
Nucleon structure functions were ﬁrst measured by
lepton deep-inelastic scattering oﬀ nucleon1) . The
RHIC Spin experiments2) , of which RIKEN Nishina
Center is a major participant through RIKEN-BNL
Reseach Center, plan to measure some new types of thestructure functions such as transverse-polarized spin
structure function, as well as more conventional unpolarized or longtudinaly polarized ones.
RIKEN-BNL-Columbia (RBC) collaboration worked
on numerical lattice-QCD theoretical calculations of
moments of these structure functions3,4) , as well as
nucleon elastic form factors4,5) . More recently the
UKQCD collaboration joined the eﬀort: Based on
our realistic 2+1-ﬂavor dynamical domain-wall quark
lattice-QCD numerical ensembles6) , we reported an
unexpectedly huge ﬁnite-size eﬀect on axialvectorcurrent form factors of nucleon7,8) . It appears a lattice33
spatial volume larger than (∼ 7 × m−1π ) , or (∼ 10fm)
at the physics point, would be necessary to accurately
calculating these form factors to within 1% accuracy,
3
3
in contrast the volumes of (∼ 4 × m−1π ) , or (∼ 3fm)
at unphysical mπ ∼ 300MeV, presently used in ourstate-of-the-art calculations.
A question thus arises whether such small volumes
presently used are suﬃcient for the structure function
calculations. Small volumes may indeed be suﬃcient as
the structure functions are measured in deeply inelastic processes, in contrast to the elastic form factors.
During the past year the RBC and UKQCD collaborations tested if our present volumes are suﬃcientby comparing the calculations on two volumes, thesmaller (∼ 1.8fm)3 and the larger (∼ 2.7fm)3 , of thelowest moments, the isovector quark momentum fracation, xu−d , the ﬁrst moment of the unpolarized structure function, and the isovector quark helicity fraction,
x∆u−∆d , the ﬁrst moment of the polarized9) .
The ratio, xu−d /x∆u−∆d , of these two moments
is summarized in Fig. 1: no descernible volume nor
mass dependence can be observed while agreementwith experiment is excellent. This is in clear contrast
to a similarly naturally renormalized ratio of isovector axial and vector charges, gA /gV , which deviatesaway from experiment because of the huge ﬁnite-size
eﬀect7,8) that becomes severe in the region where a parameter mπ L, the product of pion mass mπ and latticelnear extent L, is below 7. The absolute values of thequark momentum and helicity fractions also do notshow any volume dependence, but show encouraging
∗1
∗2
∗3

Institute of Particle and Nuclear Studies, KEK
SOKENDAI Graduate University of Advanced Studies
RIKEN BNL Research Center- 85 -

1.2

1

0.8

0.6

0.4

0.2

0
0

0.1

0.2

0.3

0.4

0.5

Fig. 1. Ratio of the quark momentum and helicity fractions, plotted against pion mass squared, m2π , in GeV2 :×’s denote results from larger (2.7fm)3 volume, +’sfrom the smaller (1.8fm)3 , and  the experiment.

trending toward experiments at low quark mass. These
results suggest low moments of nucleon structure functions in general can be calculated on a relatively small
3
3
lattice volume, as small as (∼ 3 × m−1π ) , or (∼ 5fm)
at the physical pion mass, in contrast to axialvector
form factors that require much larger volume7,8) .
I thank the RBC and UKQCD Collaborations.
RIKEN, Brookhaven National Laboratory and the US
DOE, Edinburgh University and the UK PPARC provided the facilities essential for this work.
References
1) J.I. Friedman, H.W. Kendall and R.E. Taylor, Rev.
Mod. Phys. 63, 629 (1991); J.I. Friedman, ibid. 615;
H.W. Kendall, ibid. 597; R.E. Taylor, ibid. 573.
2) G. Bunce et al., [RHIC Spin], (2008), http://spin.riken.
bnl.gov/rsc/report/spinplan 2008/spinplan08.pdf.
3) K. Orginos et al., [RBC], Phys. Rev. D 73, 094503(2006) [arXiv:hep-lat/0505024].
4) H.W. Lin et al., [RBC], Phys. Rev. D 78, 014505 (2008)[arXiv:0802.0863 [hep-lat]].
5) S. Sasaki et al., [RBC], Phys. Rev. D 68, 054509 (2003)[arXiv:hep-lat/0306007].
6) C. Allton et al., [RBC+UKQCD], Phys. Rev. D 78,
114509 (2008).
7) T. Yamazaki et al., [RBC+UKQCD], Phys. Rev. Lett.
100, 171602 (2008) [arXiv:0801.4016 [hep-lat]].
8) T. Yamazaki et al., [RBC+UKQCD], Phys. Rev. D 79,
114505 (2009) [arXiv:0904.2039 [hep-lat]].
9) S. Ohta, [RBC+UKQCD], PoS (LAT2009) 131 (2010)[arXiv:0910.5686 [hep-lat]].

RIKEN Accel. Prog. Rep. 43 (2010)

A ﬁrst principles calculation of proton decay matrix elements
Y. Aoki∗1 [RBC and UKQCD collaborations][Lattice QCD, grand uniﬁed theories]
Proton decay, once observed, is a smoking gun evidence of the physics beyond the standard model. It
naturally happens under (SUSY) GUT. On-going deep
mine experiments, though yet to observe an event,are pushing up the lower bound of of the proton lifetime, excluding GUT models which allow protons decay more frequently. Hadronic matrix elements, especially the relevant form factor W0 of the proton decay
are essential ingredients in estimating lifetime of proton. Lattice QCD provides the most reliable estimate
for such low energy hadronic quantities.
A partial decay width, e. g. for p → π 0 + e+ , reads
Γ(p → π 0 + e+ ) ∝ |C · W0 (p → π 0 )|2 ,where C depends mass spectrum of underlying (SUSY)
GUT theory (X boson mass, sfermion masses · · ·).
W0 (p → meson is the relevant form factor of the proton to meson transition with a certain three-quark
baryon number violating operator. The partial lifetime is given by τ = 1/Γ.
The form factor W0 of one body decay (p → meson),which are process and operator dependent, can be directly calculated through a combination of three- andtwo-point functions on the lattice. There is also amethod to calculate the matrix element by using an approximation through chiral perturbation theory reduction, where two low-energy constants need to be calculated on the lattice. Since the former (direct method)
requires many types of quark correlation functions, it
is more demanding (typically factor 10 computer time)than latter (indirect method).
In our ﬁrst attempt1) to calculate the matrix elements, we have used the domain-wall lattice fermion
formulation, which preserves the chiral symmetry ina precision suﬃcient to protect the operator mixing
due to lattice artifact. The direct calculation was performed using the quenched approximation where all
the sea quark eﬀects were neglected by hand. We
also performed the indirect calculation, where we havechecked that 1) the systematic error on the low energy constants from the ﬁnite lattice spacing is negligible, and 2) those from the quenching appeared tobe small by comparing quench (dynamical number of
ﬂavor nf = 0) and nf = 2 computations. We also
have developed the non-perturbative renormalization(NPR) scheme for the baryon number violating threequark operators, which helped to reduce the systematic error compared to the perturbative renormalization scheme employed in all lattice calculations performed by then. An important outcome of this pilot∗1

RIKEN-BNL Research Center

study is that the indirect approximation always underestimates the magnitude of the matrix elements,
thus, is unjustiﬁably generous for any (SUSY) GUTs.
Although the indirect method is good to an order-ofmagnitude precision, the more demanding, direct calculation must be performed for more accuracy.
We now can perform a ﬁrst principles calculationof the proton decay form factors, using the nf = 3
domain-wall fermion simulation to take into accountall the light sea quark eﬀects. As the pilot study indicate, the use of chiral fermion formulation with our
NPR help keep the systematic error under control.
First we have looked at the the low energy constants
α and β 2) . They appeared to be consistent with thenf = 0 and 2. We are now calculating the all possible
p → pseudoscalar meson form factors. The preliminary result is given in Fig. 1.
0−<π |(ud)RuL|p>0<π |(ud)LuL|p>0<K |(us)RuL|p>0<K |(us)LuL|p>+−<K |(us)RdL|p>+<K |(us)LdL|p>+−<K |(ud)RsL|p>+<K |(ud)LsL|p>+−<K |(ds)RuL|p>+−<K |(ds)LuL|p><η|(ud)RuL|p><η|(ud)LuL|p>0

directindirect

0.05

0.1
2
W0 [GeV ]

0.15

0.2

Fig. 1. Preliminary result of relevant form factors W0 of
the proton decay matrix elements in the full dynamical
domain-wall quark calculation. Operators have beenmatched to MS, NDR at µ = 2 GeV, using NPR.

For the current precision the results are consistent
with the quenched ones1) . Results from the proper
direct calculation pose more stringent constraint to(SUSY) GUTs than the indirect calculation. They arecloser to the lower bound of the various phenomenological estimates, which had been used for the conservative estimate of the proton lifetime. Improvementof this result is underway by increasing the statistics.
and through more elaborate analysis.
This project is supported in part by US DOE
through USQCD collaboration, Japanese MEXT grant
Kakenhi No. 21540289.
References
1) Y. Aoki et al., Phys. Rev. D75 (2007) 014507.
2) Y. Aoki et al., Phys. Rev. D78 (2008) 054505.

- 86 -

RIKEN Accel. Prog. Rep. 43 (2010)

Quark masses from lattice QCD and QED†
T. Izubuchi∗1∗2 and T. Ishikawa,∗2∗3 for RBC and UKQCD Collaborations3

16 x32x16, β=2.13, mud=0.01, ms=0.04, 48 hits

†

∗1
∗2
∗3
∗

-11
-11.5
log ( w )Lattice QCD+QED determination of the most basic parameter, the masses of up, down, and strange
quarks, is presented. We take into account theisopin (and SU (3)F ) breaking eﬀect due to diﬀerent masses and electric charges among up,down andstrange quarks based on dynamical lattice QCD simulation including electromagnetic (QED) eﬀects, which
are needed for accurate hadron mass analysis. This is
the the world ﬁrst determination of quark masses directly addressing the two sources of isospin breaking
using lattice chiral quarks with NF = 2 + 1 dynamicalquark eﬀects.
We perform the lattice QCD with photon coupled
to electromagnetic (EM) charge of quarks following
the pioneering work1) . The photon ﬁeld, Aem,µ (x), in
its non-compact implementation, is generated in the
Feynman gauge with eliminating the diverging zeromodes. The gluon ﬁeld ensembles are generated by
RBC and UKQCD collaborations2) using the domainwall fermions (DWF) as lattice quarks. The detail settings and parameters of the simulation are in 3). Since
the photon ﬁeld is not conﬁned, it propagates for longer
distances than the gluon ﬁeld. Results from two lattice
volumes, V = (16a = 1.84fm)3 and (24a = 2.75fm)3 ,are compared to each other to check the ﬁnite volume
eﬀects. We found that averaging over meson propagators of positive (+e) and negative QED charges (−e)
is very useful to reduce the statistical noise4) since its
O(e) contribution to the noise is explicitly cancelled in
the average keeping the physical signal, which is O(e2 ).
We ﬁt the psuedosclar mass MPS (m1 , q1 , m3 , q3 ; ml ),made of quark pairs ψ1 (x) and ψ3 (x), each pair of
whose charge and mass is (mi , qi ) with i = 1, 3 using
both of SU (3) + γ chiral perturbation theory (ChPT)and SU (2) + Kaon + γ ChPT. The latter is derived byourselves for the ﬁrst time and is preliminary. From theﬁt, we obtained the physical quark masses by solving
the three equations of ChPT meson mass formula for
π ± (139.57018(35) MeV), K ± (493.677(13) MeV), andK 0 (497.614(24)M eV ) treating the three quark masses
mup , mdown , mstrange as unknown variables, The preliminary resultsare shown in Table 1. The disconnected
quark loops, needed for π 0 , is not calculated in our simulation, so we refrain from using π 0 mass in this work.
We will reduce the discretization error using ﬁner
lattice ensemble, and the chiral extrapolation error us-

-10.5

-12
-12.5
-13
-13.5

400

500

600
700
800
900
QCD vacuum number (trajectory number)

1000

1100

Fig. 1. log(w) for several QCD vacuum.
Fit, V
SU(3), (2.7 fm)3
SU(3), (2.7 fm)3
SU(3), (1.8 fm)3
SU(3)δmres ,(2.7 fm)3
SU(2) (2.7 fm)3

Condensed from Reference 3)
Brookhaven National Laboratory, USA
RIKEN-BNL Research Center,USA
Physics Department, University of Connecticut, USA
We thank RIKEN, Brookhaven National Laboratory and US
DOE, University of Edinburgh and UK PPARC for providing the facilities essential for the completion of this work.

- 87 -

mcut
40
70
70
40
70

mup
2.76(26)
2.55(23)
2.93(19)
2.52(24)
2.24(16)mdown
4.80(46)
4.78(46)
4.85(29)
4.74(45)
4.62(24)

mstrange
95(9)
95(9)
95(5)
95(9)
101(5)

Table 1. Preliminary determinations of quark masses in
MeV in MS(NDR) at µ = 2 GeV using SU(3) ChPT+γ
ﬁt. Errors are only statistical. The last two rows are
the ﬁt results with an alternative treatment for residual chiral symmetry breaking and the the results from
SU(2) ﬁt.

ing lighter quark mass simulations. Other sources ofsystematic error include the dynamical EM charge effects. The correction for the missing EM charge ofsea quark in the above results can be calculated by thereweighting factor, which is the ratio of the sea quark’s
Dirac determinants between with and without the EM
charges:
w = det D(mud , ms , e)/ det D(mud , ms , e = 0)
In Figure 1, log(w) for a few QCD vacuum is plotted.
We found ﬂuctuation among vacuum is under control:
typical ﬂuctuation for log(w) is less than three for thisvolume, which is an encouraging result for eliminating
the error of the sea quark charges omission.
In Reference 3), we also presented preliminary results for the mass diﬀerence between Nucleon and Proton, which is an important necessary condition for thestability of the proton in this nature, as well as thebreak-up of the charge splitting of Kaon mass into thepart coming from up, down quark mass diﬀerence andthat from electromagnetic eﬀects.
References
1) A. Duncan, et. al., Phys. Rev. Lett. 76 (1996) 3894.
2) RBC-UKQCD Collaboration, C. Allton et. al., Phys.
Rev. D78 (2008) 114509.
3) T. Izubuchi, in KAON09 Proceedings (2009).
4) T. Doi, et. al. PoS LAT2006 (2006) 174.

RIKEN Accel. Prog. Rep. 43 (2010)

QCD phase structure in three-ﬂavor random matrix theory†
R. Arai∗1 and N. Yoshinaga∗1[QCD, phase transition]
In hadron physics, the study of quantum chromodynamics (QCD) at ﬁnite temperatures and nonzero
baryon densities is fascinating. Therefore, experimental studies on heavy ion collisions have been actively
performed.
At zero temperature, for high isospin chemical potential µI ≥ mπ /2, pion condensation occurs. Thisis also predicted by chiral perturbation theories1) andhas been observed in lattice QCD simulations2) . The
extension of two-ﬂavor analyses to the three-ﬂavor caseindicates that kaon condensation occurs in the regionof high strangeness chemical potential µS ≥ mK 3,4) .
The kaon condensation is also expected to occur inhigh density nuclear matter such as neutron stars5) .
In a previous study, we constructed a three-ﬂavor
random matrix model with nonzero quark chemical
potentials at a ﬁnite temperature6) . We found that
QCD phase structure in the three-ﬂavor random matrix model qualitatively agrees with that in chiral perturbation theory3) and the three-ﬂavor Nambu-JonaLasinio (NJL) model4) at zero temperature.
In this report, we study the QCD phase diagram at
a ﬁnite temperature and for a nonzero baryon number,
nonzero isospin, and nonzero strangeness chemical potentials using the three-ﬂavor random matrix model.
In the case of zero baryon number chemical potential(µB = 0), our model qualitatively agrees with QCD
phase diagrams of the three-ﬂavor NJL model4) .
A phase diagram in the (µB , T ) plane for light quark
masses mu and md with mu = md = 0.01 and thes quark mass ms = 0.25 at ﬁnite isospin and ﬁnite
strangeness chemical potentials is shown in Fig.1. Below the threshold values of pion and kaon condensation, the nonzero µI breaks the ﬂavor symmetry forthe light quarks and separates out the lines of ﬁrstorder phase transitions which coincide with each otherfor u and d quarks for µI = 0. This observation agrees
with the two-ﬂavor random matrix model7) . Regarding
the phase transition for s quarks, the line of ﬁrst-orderphase transition is in the regime of large baryon number chemical potential even if µS = 0. The nonzero
value of µS shifts the phase transition line toward
larger baryon number chemical potentials. However,the critical temperature is not aﬀected at all by theisospin and strangeness chemical potentials.
Our analysis gives very important results relating toactual instances where µB , µI , and µS are nonzero,such as the interior of neutron stars or relativistic†∗1

Condensed from the article in Phys. Rev. D 85, 017501(2009)
Department of Physics, Saitama University- 88 -

heavy ion collisions. An increase in µI results in thecritical end point for u quarks being shifted toward
smaller values of µB , as described for the two-ﬂavor
random matrix model7) . Consequently, reaching thecritical end point for u quarks might become easierthrough relativistic heavy ion collision experiments.
Similarly, an increase in µS results in the critical end
point for s quarks being shifted toward larger values ofµB . Thus, the critical phenomenon for s quarks is notexpected to occur in heavy ion collision experiments,
but only in the central interior region of neutron stars.
References
1) D.T. Son and M.A. Stephanov: Phys. Rev. Lett. 86,
592 (2001).
2) J.B. Kogut and D.K. Sinclair: Phys. Rev. D 66, 014508(2002).
3) J.B. Kogut and D. Toublan: Phys. Rev. D 64, 034007(2001).
4) A. Barducci, R. Casalbuoni, G. Pettini, and L. Ravagli:
Phys. Rev. D 71, 016011 (2005).
5) N.K. Glendenning and J. Schaﬀner-Bielich: Phys. Rev.
Lett. 81, 4564 (1998).
6) R. Arai and N. Yoshinaga: Phys. Rev. D 78, 094014(2008).
7) B. Klein, D. Toublan, and J.J.M. Verbaarschot: Phys.
Rev. D 68, 014009 (2003).

1µI G = 0.1µS G = 0.1

TG 0.5

σu
σd
σs
0
0.8

1.2

σd

σs

σs
1.6

µB G

2

2.4

Fig. 1. Phase diagram in the (µB , T ) plane with mu =md = 0.01 and ms = 0.25 for µI = µS = 0.1. The
solid lines indicate lines of ﬁrst-order phase transition
for each ﬂavor. The dotted lines indicate lines of ﬁrstorder phase transition for µI = µS = 0. σu , σd , andσs represent chiral condensates for u, d, and s quarks,
respectively.

RIKEN Accel. Prog. Rep. 43 (2010)

Imaginary part of the real-time static potential at strong coupling†
A. Dumitru∗1[QCD, AdS/CFT correspondence, Quarkonium, Quark-Gluon Plasma]
Consider the potential at ﬁnite temperature between
static sources in a color singlet state deﬁned via the
expectation value of a Wilson loop
exp [−itV(r, T )] ≡ �W (C)� .

(1)

The rectangular contour C extends over a spatial distance r and over a time t → ∞. The expectation
value �W (C)� could also be calculated as a functionof Euclidean time τ but then requires analytic continuation, τ → it, before the limit t → ∞ is taken1) .
This makes it rather diﬃcult to evaluate V(r, T ) within
non-perturbative lattice-QCD approaches.
At weak coupling the potential V(r, T ) can be obtained directly from the Fourier transform of the physical “11” component of the resummed propagator for
static gluons in the real-time (Schwinger-Keldysh) formalism of thermal ﬁeld theory2) . Due to Landau
damping of the exchanged gluon the resulting potential exhibits an imaginary part: for rT � 1, in theleading-logarithmic approximation it is proportional to
Im V ∼ −αs2 CF Nc T (rT )2 log (rT )−1 . This translates
into a width of the Υ state which is on the order of tensof MeV (at T = 300 MeV) and may lead to signiﬁcant
suppression of the Υ → �+ �− process in heavy-ion collisions at RHIC and LHC3) . We emphasize that this is
not due to Debye screening of the real part of V(r, T )which indeed is weak at rT < 1.
The expectation value of W (C) can also be calculated for N = 4 SYM at large t’Hooft coupling,
λ = g 2 Nc � 1, which at Nc → ∞ admits a weakly
coupled dual gravity description on AdS5 ×S5 . The
conformal N = 4 SYM theory is used here as a toy
model for the deconﬁned phase of QCD. An inﬁnitely
massive excitation in the fundamental representationof SU (Nc ) in the CFT is dual to a classical string in
the bulk hanging down from a probe brane4) . The conﬁguration which minimizes the action of a static QQ̄
pair is a U-shaped curve that connects the string endpoints at the boundary and has a minimum at some U∗
in AdS5 . At ﬁnite temperature, the dual description of
the gauge theory involves a near-extremal black branein the bulk. The horizon is located at Uh = πR2 T ,where R denotes the radius of AdS5 .
In the gravity description the imaginary part ofthe static potential is due to ﬂuctuations about
the extremal solution Uc (x)3) . When the bottomof the string is suﬃciently close to the horizon,∗1

Department of Natural Sciences, Baruch College (CUNY),
New York and RIKEN-BNL Research Center (RIKEN fellow)- 89 -

classical worldsheet ﬂuctuations δU (x) can generate� imaginary contribution to the action SNG ∼� an
dx U � 2 + V (U ) when both Uc� 2 and V (Uc ) aresmall; i.e. near the bottom of the extremal string. This
gives3)�
3ζ 4 − 1 �π √Θ ζ − 3−1/4 (2)λT
Im VQQ̄ = − √ζ
24 2
where ζ ≡ Uh /U∗ < 1. At small LT it follows fromthe zero-temperature
solution4) that LT = b ζ with√b = 2Γ(3/4)/ π Γ(1/4).
The imaginary part of the potential shifts the Bohrenergy level obtained from the Coulomb-like vacuum
potential,
E0 → E0 − iΓ. For the ground state of the√∼ λ/r potential, this shift amounts to
� �
�
√
�4
π λ b
a0 T
45
−2 ,
(3)
ΓQQ̄ = √b48 2 a0√
where a0 = Γ(1/4)4 /2π 2 λ mQ is the Bohr radius.
The width decreases with the quark mass and with thet’ Hooft coupling, approximately as ΓQQ̄ ∼ 1/λ m3Q ; itincreases rapidly with the temperature,∼ T 4 . For√
mQ = 4.7 GeV, T = 0.3 GeV, λ = 3 we obtainΓΥ � 48 MeV. This thermal width is small comparedto the binding energy of the Υ but large compared toits electromagnetic decay width. Thus, a suppressionof Υ → �+ �− decays in heavy-ion collisions is expected,
RAA (Υ → �+ �− ) � e−Γ̄t < 1 .

(4)Here, Γ̄ denotes an average of the decay rate over thelife time t of the high-temperature phase. The experimental analysis of this process in heavy-ion collisions
at RHIC is currently in progress5) .
References
1) M. Laine, O. Philipsen, P. Romatschke and M. Tassler,
JHEP 0703, 054 (2007).
2) N. Brambilla, J. Ghiglieri, A. Vairo and P. Petreczky,
Phys. Rev. D 78, 014017 (2008); A. Dumitru, Y. Guo
and M. Strickland, Phys. Lett. B 662, 37 (2008); Phys.
Rev. D 79, 114003 (2009); O. Philipsen and M. Tassler,
arXiv:0908.1746 [hep-ph].
3) J. Noronha and A. Dumitru, Phys. Rev. Lett. 103,
152304 (2009).
4) J. M. Maldacena, Phys. Rev. Lett. 80, 4859 (1998);
S. J. Rey and J. T. Yee, Eur. Phys. J. C 22, 379 (2001).
5) E. T. Atomssa [PHENIX Collaboration], Nucl. Phys. A
830, 331C (2009).

5.

Particle Physics

RIKEN Accel. Prog. Rep. 43 (2010)

Tenth-order QED contributions to lepton g −2
T. Aoyama,∗1 K. Asano,∗2 M. Hayakawa,∗2 T. Kinoshita,∗3 M. Nio, and N. Watanabe∗2[QED, anomalous magnetic moment, electron, muon]
The anomalous magnetic moment of electron, called
g−2, plays a central role in testing the validity of quantum electrodynamics (QED). A Harvard team recently
reported an astonishing result regarding a newly measured value of the electron anomaly ae = (g−2)/21)
ae = 1 159 652 180.73 (0.28) × 10−12 (0.24 ppb).(1)To match the experimental precision, the theory
should take into consideration the QED contributions
up to the tenth order of the perturbation theory. The
largest uncertainty in the current theoretical value
comes from the yet-uncalculated tenth-order contribution. There are 12672 vertex Feynman diagrams
that contribute to the tenth-order g−2. They are further divided into 32 gauge-invariant sets, as shown in
Fig. 1. The contributions from 17 sets, sets I(a–f),II(a,b), II(f), VI(a–c), VI(e,f), and VI(i–k), were previously determined by us.2) In this article, we report
our progress on the evaluation of the remaining 15 sets.
The first automation system we developed is gencodeN, which deals with Feynman diagrams without
fermion loops.3) Given one-line information specifying
a diagram, gencodeN generates a set of FORTRAN
programs that can be used for numerical evaluation.
With the help of gencodeN, we generated programsfor sets III(a,b), IV, and V. The numerical evaluationof the sets III(a,b) and IV was relatively easy and wedetermined anomaly contributions from these sets. Set
V consists of 6354 diagrams; its numerical evaluationis very difficult and requires large computational resources. For several years, RIKEN’s Super-Combined
Cluster System(RICC) had been used for the evaluation of set V. Since fall 2009, a new computer RIKEN’sIntegrated Cluster of Clusters(RICC) is being used forthe numerical evaluation of set V. The evaluation isstill in progress.
The second automation system, gencodevpN,
deals with vacuum-polarization diagrams consisting of
single lepton loops. This enables us to rapidly evaluate
sets I(g,h), I(i), and II(c,d).4)
The last automation system, gencodeLBLN, deals
with diagrams that include light-by-light scattering
subdiagrams. The anomaly contributions from Sets
IV(d,g,h) were then determined.
Sets II(e) and III(c) also include light-by-light scattering subdiagrams, but unlike in sets IV(d,g,h), none
∗1
∗2

∗3

Institute of Particle and Nuclear Studies, High Energy Accelerator Research Organization (KEK)
Department of Physics, Nagoya University
Laboratory for Elementary-Particle Physics, Cornell University- 91 -

I(a)

I(b)

I(c)

I(d)

I(e)

I(f)

I(g)

I(h)

I(i)

I(j)

II(a)

II(b)

II(c)

II(d)

II(e)

II(f)

III(a)

III(b)

III(c)

IV

V

VI(f)

VI(a)

VI(b)

VI(c)

VI(d)

VI(e)

VI(g)

VI(h)

VI(i)

VI(j)

VI(k)

Fig. 1. Feynman diagrams contributing to the tenth-order
lepton g−2. Typical diagrams from 32 gauge-invariant
sets are shown. An external photon vertex is omitted
for simplicity. There are 12672 vertex diagrams in total.

of the photon legs of a light-by-light scattering loop isan external magnetic field. Such a diagram requires adelicate treatment because a light-by-light scattering
loop causes ultraviolet divergence. Nagoya group of
the present authors investigated these diagrams, andthe results they obtained were confirmed by an independent check by the rest of us.5)
The investigation of set I(j), which has a very different structure from other diagrams, was also dominatedby the Nagoya Group. The result has been published.6)
At present, all the 32 gauge-invariant sets of thetenth-order diagrams has been investigated. Furthermore, we have computed the contributions to the muong−2 from the diagrams involving fermion loops. We willsoon determine the entire contributions of the tenthorder term to both electron and muon.
References
1) D. Hanneke, S. Fogwell, and G. Gabrielse: Phys. Rev. Lett.
100, 120801 (2008).
2) T. Kinoshita and M. Nio: Phys. Rev. D 73, 053007(2006).
3) T. Aoyama, M. Hayakawa, T. Kinoshita, and M. Nio:
Nucl. Phys. B 740, 138 (2006); ibid 796, 184 (2008).
4) T. Aoyama, M. Hayakawa, T. Kinoshita, and M. Nio:
Phys. Rev. D 78, 113006 (2008).
5) T. Aoyama, K. Asano, M. Hayakawa, T. Kinoshita,
M. Nio, and N. Watanabe: Phys. Rev. D81, 053009(2010).
6) T. Aoyama, M. Hayakawa, T. Kinoshita, M. Nio, andN. Watanabe: Phys. Rev. D 78, 053005 (2008).

RIKEN Accel. Prog. Rep. 43 (2010)

Color Magnetic Flux Tubes in Dense QCD†
M. Eto, E. Nakano,∗1 and M. Nitta∗2[High density QCD, Color superconductivity, Topological soliton]
Theoretical studies suggests that a color superconducting phase exists in the high-density, lowtemperature region of the QCD phase diagram1). Sucha state of matter is considered to occur in the coreof compact stars. To capture their signatures, it isnecessary to determine the various properties of color
superconductivity.
In the three-ﬂavor case, which we are interested in,
and in higher-density regions where the eﬀects of quark
masses can be ignored and the three-ﬂavor symmetryeﬀectively holds, the color-ﬂavor locking (CFL) phasewould be generated with the order parameter
L(R)

Φkγ

L(R)

= ǫijk ǫαβγ �qiα

L(R)

Cqjβ

� ∝ δkγ ,where i, j, and k and α, β, and γ are ﬂavor and color
indices, respectively. This diagonal conﬁguration that
locks ﬂavor and color minimizes the free energy2). In
the CFL phase, the symmetry G ≃ SU (3)C ×SU (3)L ×
SU (3)R ×U (1)B breaks down to the diagonal symmetry
H ≃ SU (3)C+L+R ≡ SU (3)C+F ; here we consider thecase where all the quarks are massless, and the leftand right-handed quarks are separated.
When a symmetry of a system is spontaneously broken in the ground state, various kinds of topological defects occur; these defects correspond to a nontrivial topology of the order parameter space. In thisstudy, we investigate the vortices in the CFL phase4) –8). One might expect that stable vortices associatedwith breaking of the U (1)B symmetry, but this is only
true for the conﬁning phase such as a hadronic matter.
Each of the vortices is unstable and decays into three
non-Abelian vortices3), which are found in color magnetic ﬂux tubes7) . In the core of rotating stars, thegenerated non-Abelian vortices might form a vortex
lattice, similar to the case of superﬂuid vortices in ahelium superﬂuid or a Bose-Einstein condensate. The
lattice structure of vortices can be determined fromthe details on vortex-vortex interaction.
The most signiﬁcant features of the non-Abelianvortices are the additional NG zero modes associatedwith the additional breaking of symmetry that appear
around the vortex string beause of the creation of thevortex: H = SU (3)C+F → K = [U (1) × SU (2)]C+F .
These modes parametrize the complex projective space
H/K = CP 23) , and they are called orientational zeromodes. Points in CP 2 have a one-to-one correspon†∗1∗2

Condensed from the article in Phys.Rev.D80:125007,(2009)
and Phys.Rev.D80:125011(2009)
Extreme Matter Institute, GSI, Darmstadt, Germany
Department of Physics, and Research and Education Center
for Natural Sciences, Keio University,- 92 -

dence with the color degrees of freedom of the vortex.
In the study8) , we have obtained full numerical solutions for the semi-superﬂuid non-Abelian vortices for awide range of parameters. We have analytically shownthat both the scalar and gauge ﬁelds asymptoticallybehave as e−mr , where m = min(mG , mχ ) and mGand mχ are the masses of the gluons and the traceless part of the scalar ﬁelds, respectively. We have also
numerically evaluated the width of the color ﬂux andfound that it is not always equal to the penetration
depth, which is the Compton wave length m−1
G . When
the gluon mass is smaller than the scalar masses, thewidth cannot exceed certain values that are determinedon the basis of the masses of other ﬁelds; hence, we
found that the color ﬂux is conﬁned to the scalar core.
In the study10) , we have explicitly shown the normalizability of the orientational zero modes and derived
the low-energy eﬀective world-sheet theory of a nonAbelian semi-superﬂuid vortex. To this end, we havegeneralized the derivation of the eﬀective action of the
BPS non-Abelian vortex string; the derivation was presented by Gorsky, Shifman and Yung9) . They foundthe decay constant (overall constant) in the CP N −1
model to be 4π/gs2 where gs is a gauge coupling constant. In the present case of a non-Abelian vortex in
the CFL phase, we have found that the decay constantin the CP 2 model is not equal to 4π/gs2 as in the BPS
case. The decay constant can be greater or smaller depending on the parameter regions. Our study will be
the ﬁrst step in the investigation of the dynamics ofsemi-superﬂuid non-Abelian vortex strings, which will
be relevant, for instance, in neutron star physics.
References
1) K. Rajagopal and F. Wilczek, arXiv:hep-ph/0011333.
2) M. G. Alford, K. Rajagopal, and F. Wilczek; Nucl.
Phys. B 537, 443 (1999)
3) E. Nakano, M. Nitta, and T. Matsuura; Phys. Rev. D
78, 045002 (2008) Prog. Theor. Phys. Suppl. 174, 254(2008)
4) I. Giannakis and H. c. Ren; Phys. Rev. D 65, 054017(2002)
5) K. Iida and G. Baym; Phys. Rev. D 66, 014015 (2002)
6) M. M. Forbes and A. R. Zhitnitsky; Phys. Rev. D 65,
085009 (2002)
7) A. P. Balachandran, S. Digal, and T. Matsuura; Phys.
Rev. D 73, 074009 (2006)8) M. Eto and M. Nitta; Phys. Rev. D 80, 125007 (2009)9) A. Gorsky, M. Shifman, and A. Yung; Phys. Rev. D 71,
045010 (2005)10) M. Eto, E. Nakano, and M. Nitta; Phys. Rev. D 80,
125011 (2009)RIKEN Accel. Prog. Rep. 43 (2010)

Scattering of Giant Magnons in CP3 †Y. Hatsuda and H. Tanaka∗1[AdS/CFT correspondence, Integrability, Solitons]
The gauge/gravity duality helps us to understandstrongly coupled dynamics in gauge theory. The
AdS/CFT correspondence1) is a useful tool to study
this duality. Recently, Aharony, Bergman, Jafferis,and Maldacena (ABJM) proposed a three-dimensional
N = 6 superconformal Chern-Simons theory with the
U (N )×U (N ) gauge group.2) This theory is used to describe the low-energy effective theory of multiple M2branes. The ABJM model has another interesting feature. It provides a new example of the AdS/CFT correspondence. The dual string theory is the type IIA
superstring theory on the AdS4 × CP3 background.
Hereafter, we refer to this duality as the AdS4 /CFT3
duality.
In the well-known duality between the fourdimensional N = 4 super Yang-Mills and the type IIB
superstrings on AdS5 × S5 , both theories have the integrable structures that play a key role in understanding
the spectrum on both sides. The AdS4 /CFT3 duality
also has a similar integrable structure. The spectral
problem for the ABJM model is converted to that foran alternating spin-chain model. Once the vacuum of
the model is determined, the excitations over the vacuum, which are called magnons, are classified on thebasis of the residual SU (2|2) global symmetry. Eachmagnon bound-state has the following dispersion relation:

 
Q2
P
+ 4h2 (λ) sin2,
(1)
Q (P ) =42
where P is the total momentum, and the integer Q isthe number of magnons. The function h(λ) of the ’t
Hooft coupling λ behaves under weak or strong coupling as follows:
3(λ  1) ,λ+ O(λ )(2)h(λ) =
λ/2 + O(1) (λ  1) .

The string duals of such magnon bound-states are
known as dyonic giant magnons; these were originally discovered by Hofman and Maldacena.3) In the
AdS4 /CFT3 duality, there are two kinds of dyonic giant magnons: one exists in the CP2 subspace of CP3 ,and the other in RP3 .
The purpose of this study is to investigate thescattering of two CP2 dyonic giant magnons. The
scattering matrix is a fundamental tool to study the
AdS/CFT spectrum in the large R-charge/spin sector.
†∗1

Condensed from the article in JHEP 1002, 085 (2010)
Department of Physics, University of Tokyo- 93 -The S-matrix is also important for studying the finitesize effects by applying the Lüscher corrections in bothstring and gauge theories. The exact S-matrix of the
AdS4 /CFT3 duality has already been conjectured by
Ahn and Nepomechie.4) Since the CP2 dyonic giant
magnons are new solutions, which do not exist in thecase of AdS5 × S5 , it is important to investigate theirscattering. This will be useful for understanding thespectral problem in the AdS4 /CFT3 duality.
We computed the classical phase shift for the scattering of two CP2 dyonic magnons, and compared itwith the conjectured S-matrix of two magnon boundstates in the large ’t Hooft coupling limit. To compute the classical phase shift, we first constructed thegeneral two-soliton solutions in the CP3 sigma-model.
We used the dressing method, which is a useful technique to obtain multi-soliton solutions, for developing
the SU (4)/U (3) coset model. Next we evaluated theclassical time delay from these two-soliton solutions.
The phase shift was finally obtained by integrating thetime delay with respect to the energy of one of twosolitons.
Our computation shows that the classical scattering phase of CP2 dyonic giant magnons agrees withthat of magnon bound-states in the ABJM model up
to the gauge-dependent term. In the ABJM model,
there are two types of excitations, that is, the oddsite excitations and even-site excitations. Our resultshows two polarizations of dyonic giant magnons that
correspond to these two kinds of excitations in the alternating spin-chain.
In this work, we focused on the classical aspects ofthe scattering phase. It is interesting to consider quantum (α ) corrections of the scattering phase in the future work.
References
1) J. M. Maldacena: Adv. Theor. Math. Phys. 2, 231(1998) [Int. J. Theor. Phys. 38, 1113 (1999)].
2) O. Aharony, O. Bergman, D. L. Jafferis, and J. Maldacena: JHEP 0810, 091 (2008).
3) D. M. Hofman and J. M. Maldacena: J. Phys. A 39,
13095 (2006).
4) C. Ahn and R. I. Nepomechie: JHEP 0809, 010 (2008).

RIKEN Accel. Prog. Rep. 43 (2010)

Gravitational Dual of Tachyon Condensation†
G. W. Gibbons,∗1 K. Hashimoto,∗2 and S. Hirano∗3[Superstring theory, D-brane, Tachyon Condensation]
There has been considerable progress in understanding non-perturbative aspects of string theory with orwithout supersymmetries. These developments culminated in the gauge/string duality primarily in supersymmetric cases1) , which would deﬁne string theory itself non-perturbatively, using conventional gauge
theories in 4 spacetime dimensions. Meanwhile, in
non-supersymmetric cases one of the most remarkableprogress is the open string tachyon condensation2) .
This describes pair-annihilation of D-branes and antiD-branes, and should be incorpolated in any kind of
non-perturbative deﬁnition of string theory.
However, these two developments have been rather
orthogonal to each other, except for two-dimensional
string theories. In this note we study an open string
tachyon condensation in the gauge/string duality andprovide an example in which these two connect at thequantitative level.
In formulating tachyon condensations in thegauge/string duality, one immediate obstacle is thatthe mass squared of open string tachyons is of orderO(1/α ) which may not be visible in the ﬁeld theory
limit α → 0. However, there exist systems in which
the open string tachyon mass remains of order O(1)(in an appropriate unit) in the limit α → 0. One such
example is a system of intersecting branes at angles.
The mass squared of open string tachyons stretched between intersecting branes is proportional to θ/α whereθ is an angle. In this case we can take the α → 0 limit,
keeping θ/α ﬁxed ﬁnite. This type of open string
tachyons manifest themselves as unstable modes in thegauge theory in the low energy α → 0 limit of intersecting D-branes3) . In the present paper we consider
a T-dual version of the system studied in3) in the ’t
Hooft limit, N → ∞ and gY M → 0 with λ = gY2 M N
ﬁxed ﬁnite.
One of the most important aspects of open string
tachyon condensation is that unstable D-branes which
support open string tachyons disappear after thetachyons are condensed. Accordingly, Sen’s conjecturestates that the height of the tachyon potential equals
the tension (energy density) of unstable D-branes2) .
Hence the height of the tachyon potential is one of
the most important and unambiguous quantities in the
open string tachyon condensation. The main objective
†

∗1
∗2
∗3

Condensed from the article in JHEP 0909 (2009) 100
DAMTP, University of Cambridge,Wilberforce Rd, Cambridge CB30WA, U.K.
Theoretical Physics Laboratory, RIKENThe Niels Bohr Institute, Blegdamsvej 17, DK-2100, Copenhagen, Denmark- 94 -of this paper is to compute the height of the tachyon
potential both in the gauge theory and the dual AdS
gravity for a large N D3-brane conﬁguration and to see
if they agree. We indeed ﬁnd an exact agreement in
the large N limit, thus providing an example of gravitational duals of open string tachyon condensation.
We consider a brane conﬁguration of a D3-D1 boundstate parallel to coincident N D3-branes at some distance. The low energy description of this system isgiven by N = 4 U (N + 1) super Yang-Mills (SYM)
theory. A D1-brane on D3-branes is represented bya magnetic ﬂux. Our brane conﬁguration is thus described by the following gauge and adjoint scalar ﬁelds
F23 = diag(B, 0, 0, · · ·) , Φ = diag(φ, 0, 0, · · ·) , (1)There appears a tachyonic instability in this background, and the endpoint of the tachyon condensation
is a bound state of N + 1 D3-branes and D1-branes.
The ﬁeld conﬁguration of the end point is(2)
F23 = diag NB+1 , NB+1 , · · · , NB+1 , Φ = 0.

If we compute the energy diﬀerence of these two conﬁgurations by using the classical SYM hamiltonian, atlarge N , the diﬀerence of the energy yields

N B2+ O(1) .
(3)
E φ=∞ −E φ=0 =2λThis is the height of the tachyon potential at weakcoupling.
At the strong coupling, if we use the AdS/CFT, we
obtain an eﬀective action
42(2π)2 λB 2
−1
4 U
d x
− 1 .(4)1+S=(2π)3 gs
2λ
U4

where U directly corresponds to φ. Using this action,
we can show that the energy diﬀerence between U = ∞and U = 0 is precisely given by (3). We thus ﬁnd an
exact agreement.
In this note we provide an example of open string
tachyon condensations in the gauge/string duality.
The idea is to consider a brane conﬁguration in which
open string tachyons survive in the ﬁeld theory α → 0
limit. One can explore various similar brane set-ups
by generalising the example we presented.
References
1) J. M. Maldacena, Adv. Theor. Math. Phys. 2, 231(1998).
2) A. Sen, JHEP 9808 (1998) 012; Int. J. Mod. Phys. A14(1999) 4061; JHEP 9912 (1999) 027.
3) A. Hashimoto and W. I. Taylor, Nucl. Phys. B503
(1997) 193.

RIKEN Accel. Prog. Rep. 43 (2010)

Eschenburg space as gravity dual of ﬂavored N=4
Chern-Simons-matter theory†
M. Fujita∗1 and T. -S. Tai∗2[String theory, Gravity/gauge correspondence]
The program towards studying gauge/gravity correspondence in the context of AdS4 /CFT3 1) becomesconcrete owing to the pioneering work2) by Aharony,
Bergman, Jaﬀeris and Maldacena last year. They
found that constructing a much higher supersymmetric conformal ﬁeld theory (SCFT) of Chern-Simonsmatter (CSM) type is possible due to an elliptic brane
setup in Type IIB string theory. Through T-duality
and M-theory lift, one obtains N M2-branes ﬁlling(012) transverse to a 8D cone: Cone(B7 ) (B7 = S 7 /Zk )along (345678910). The corresponding gravity dual isthus a solution of 11D supergravity AdS4 × B7 after N
M2-branes backreact.
Later on, generalizing their idea to yield elliptic
N ≥ 3 SCFTs is done by attaching various kindsof (1, ki )5-branes on a stack of circular D3-branes.
The resulting ﬁeld theory at infra-red (IR) ﬁxed pointis still of quiver CSM type with product(gY M → ∞) gauge group I U (N )I . Its Lagrangian is so rigid, i.e.
CS level kI w.r.t. I-th gauge factor is determined by
two adjacent D5-brane charges kI = ki − ki−1 , while
the superpotential is obtained by integrating out nondynamical massive adjoint ΦI (⊂ vector multiplet) coupled to hypermultiplets in a typical manner.
Among many kinds of elliptic N ≥ 3 SCFTs, wewill focus on a speciﬁc type of N =4 SCFT which isconstructed via IIB N circular D3- (0126), p NS5(012345) and q (1, k)5- (012[3, 7]θ [4, 8]θ [5, 9]θ ) branes.
Note that θ (twisted angle) and gY2 M k/4π (adjointmass) are related to each other by (L: segment length
on x6 )tan θ
= gY2 M k,
L

1

L
= .
2
gY M
gs

Taking IR limit implies naturally a strongly coupled
M-theory picture. Its 11D gravity dual AdS4 × M7
parameterized by (k, p, q) is explicitly known3) and thisis the main reason why we study this kind of SCFT
here.
In this note, motivated by works on the ﬂavored
N =6 ABJM theory, we construct a new N =3 SCFT
by adding NF massless fundamental ﬂavors and study
its gravity dual. From Type IIB picture, adding ﬂavor corresponds to further attaching NF D5-branes(012789) on the circle x6 and results in a less supersymmetric N =3 SCFT. This construction is by deﬁnition
†

∗1
∗2

Condensed from the article in JHEP 062, 0909 (2009)
Department of Physics, Kyoto University
Nishina Ctr., RIKEN- 95 -

an elliptic one, so in M-theory to have N M2-branes
probing a 8D cone may thus be expected due to conformality.
We ﬁnd that this turns out to be true and the dual
geometry is now AdS4 × M̃7 parameterized by threenatural numbers (t1 , t2 , t3 ) = (qNF , pNF , kpq) without any common factor. In fact, many propertiesof M̃7 (t1 , t2 , t3 ) (modulo common factor) known as
Eschenburg space have been explored by mathematicians. For example, Cone(M̃7 ) is Ricci-ﬂat with special Sp(2) holonomy. Namely, it is hyperKähler andthe base M̃7 must be tri-Sasakian (which preservesa fraction 3/16 of 32 SUSY). Moreover, the cone isavailable through applying a hyperKähler quotient to
a 3D (ﬂat) quaternionic space. The equivalence between two descriptions seems
3straightforward because
three moment maps µQ = i=1 ti µi , pµ1 + qµ2 andkqµ2 + NF µ3 are linearly independent.
On the geometry side, we are led to compute the volume of 7-cycle of Eschenburg space by taking advantage of a formula given in5) . Also, the on-shell actionof IIA probe D6-branes is taken care of. The correctembedding of D6-branes can be found by performing afurther hyperKähler quotient to Cone(M7 ). One obtains a 4D Taub-NUT space thereof over which ﬂavor
probes should wrap after doing KK reduction to IIA
theory. In addition, we consider 5-cycles among M̃7
because M5-branes wrapped over them correspond tobaryonic operators in the ﬁeld theory.
References
1) J. M. Maldacena, Adv. Theor. Math. Phys. 2 (1998)
2312) O. Aharony, O. Bergman, D. L. Jaﬀeris and J. Maldacena, JHEP 0810 (2008) 091
3) Y. Imamura and K. Kimura, Prog. Theor. Phys. 120(2008) 509
4) D. L. Jaﬀeris and A. Tomasiello, JHEP 0810 (2008) 101
5) K. M. Lee and H. U. Yee, JHEP 0703 (2007) 012

RIKEN Accel. Prog. Rep. 43 (2010)

Genus-one correction to asymptotically free Seiberg-Witten
prepotential from Dijkgraaf-Vafa matrix model†
M. Fujita∗1 , Y. Hatsuda∗2 and T. -S. Tai∗2[Seiberg-Witten theory, Matrix model]
Recently, owing to a milestone discovery made by Alday, Gaiotto and Tachikawa,1) there have been lots ofpublications and research related to their work. In particular, Dijkgraaf and Vafa2) proposed a Penner typematrix model whose classical spectral curve can reproduce the so-called Gaiotto curve G.3) Note that G consists of a punctured Riemann surface Cg,n whose moduli space Mg,n (g: genus, n: puncture) is referred to asa Teichmuller space. Surprisingly, Mg,n boils down to
the space of exactly marginal gauge couplings of a large
family of 4D N = 2 superconformal gauge theories
whose weakly-coupled cusps correspond to various patterns of colliding punctures on Cg,n . In addition, when(g, n) = (0, 6) there appear generalized quiver SCFTs
in contrast to known linear quiver SCFTs. Because G
is a rewritten Seiberg-Witten curve which emerges bytaking a thermodynamic limit of Nekrasov’s partition
function ZNekrasov = Zclassical Z1-loop Zinst , attempts towards proving an equivalence between both sides arenaturally expected.
At the level of F0 (tree-level free energy), Eguchi andMaruyoshi4) showed that F0 (including asymptotically
free cases) coincides with the original Seiberg-Witten
prepotential. Moreover, all-genus proofs in certain restricted cases are presented by executing exact matrix
integrals and comparing them with ZNekrasov .5,6)
Motivated by these works, in this work we showed
agreements between matrix model and ﬁeld theoreticalresults on the genus-one free energy F1 of N = 2 SU (2)Seiberg-Witten theory with Nf = 2, 3.
On ﬁeld theory side, the genus-one free energy iscomputed by the following formula:2
F1 = b(u) − c(u),3with1b(u) = log
2

(

du
da

)

(1)

,

c(u) =

1log(∆SW ).
8(2)Here u stands for the gauge- and monodromy-invariant
coordinate of the complex one-dimensional Coulomb
branch, a is the electric period integral of the corresponding Seiberg-Witten curve, and ∆SW denotes its
discriminant. We evaluated b(u) in terms of a large-u
expansion (weak coupling expansion) for the Nf = 2
and 3 cases. For Nf = 2, we obtain
†
∗1

∗2

Condensed from the article in e-Print: arXiv:0912.2988 [hepth]
Department of Physics, Kyoto University
Nishina Ctr., RIKEN- 96 -

b(u) =

1
3
log 2 − log ζ
4
4
3Λ2 2
−
(Λ + 6m1 m2 )ζ 2 + O(ζ 3 ),
2048

(3)

and for Nf = 3,1
Λ2
1
log 2 − log ζ −
ζ
2
4
2048
(
Λ
−
7Λ3 + 12288(m21 + m22 + m23 )Λ
8388608)+786432m1 m2 m3 ζ 2 + O(ζ 3 ),b(u) =(4)

where ζ = 1/u, and we have denoted ﬂavor bare masses
and the dynamical scale by mi ’s and Λ respectively.
On matrix model side, if we consider two-cut solutions, the genus-one free energy is given by a universal
form
4

F1 = −11 ∑1
log ∆ − log |K(�)|log Mi −24 i=112
2

1+ log |(x1 − x3 )(x2 − x4 )|,4(5)where xi (i = 1, . . . , 4) are four branch points of two
cuts, ∏�2 = (x1 − x4 )(x2 − x3 )/(x1 − x3 )(x2 − x4 ),∆ = i<j (xi − xj )2 , and K(�) is the complete elliptic
integral of the ﬁrst kind. The ﬁrst term of the righthand side in Eq. (5) is an irrelevant term and can beomitted. We conﬁrmed that the second term is equal
to −2c(u)/3 while the last two terms just agree withb(u) in the ﬁeld theoretical computation.
In summary, we provided further evidence on theequivalence between a recently proposed DijkgraafVafa matrix model and low-energy dynamics of N =2 asymptotically free SU (2) Yang-Mills theory with
Nf = 2, 3 at the level of F1 . Showing perfect agreements with the ﬁeld theoretical result, we thus extended the equivalence of ZDV and ZNekrasov at nextto-leading order non-trivially.
References
1) L. F. Alday, D. Gaiotto and Y. Tachikawa, arXiv:0906.3219[hep-th].
2) R. Dijkgraaf and C. Vafa, arXiv:0909.2453 [hep-th].
3) D. Gaiotto, arXiv:0904.2715 [hep-th].
4) T. Eguchi and K. Maruyoshi, arXiv:0911.4797 [hep-th].
5) R. Schiappa and N. Wyllard, arXiv:0911.5337 [hep-th].
6) A. Mironov, A. Morozov and S. Shakirov, arXiv:0911.5721[hep-th].

RIKEN Accel. Prog. Rep. 43 (2010)

New Gauged Linear Sigma Models for 8D HyperKahler Manifolds
and Calabi-Yau Crystals†
Y. Baba∗1 and T. -S. Tai∗1[String theory, 2D Sigma model]
A gauged linear sigma model (GLSM) in two dimensions1) is capable of describing a curved geometry (typically a sympletic or Kähler quotient space) through gauge
theory language. More precisely, the isometry of the transverse internal space gets partially gauged and chiral multiplets on the worldsheet are coupled to corresponding gauge
fields. Then, the curved geometry Cn //G arises as the supersymmetric vacuum (moduli space) of the 2D gauge theory. Note that G = Cr stands for r complexified U (1)’swith moment maps
µ : Cn → Rr ,

µa =

n

i=1

Qai |φi |2 − ρa ,

i



a

a
Qa
iλ

,

λa ∈ Ri=1



Qai |qi |2 − |q̃i |2= ξ 3a ,n
i=1

Qai 2qi q̃i = ξ 1a − iξ 2a .

∗1

JHEP02,006(2010)
Nishina Ctr., RIKEN- 97 -

 1 †√1
Σ a Σa(P † + P + k · g 2 2V )2 −
2
2g
e2a
r

d4 θ

a=1

Hi† e2Vh(i) Hi e−2Vt(i) +LF =dθ+ dθ− W + c.c.,

i



r


Φ†a e2Va Φa ,a=1

k = (k1 , · · · , kr ).

Note that W denotes some generic superpotential. Taking(e2a , g 2 ) → ∞, what we are left with are (bosonic part only)
1. Kinetic terms of (hi , φa ) (bosonic component of (Hi , Φa )2. A remnant:−g 2 (∂γ + k · A)2
3. A potential:
Vpot =
+

a

where
VD =
=





i

h(i)

|hi |2 |Qit(i)σh(i) − Qiσt(i) |2 +a

2|σa |2 |φa |2  ∂W 2   ∂W 2
g |ka σa | + + + VD ,


 2

2

i

 e2  anHere, triplets ‰’s are given level sets. By definition H ///G
has real 4(n − r) dimensions.
In this note, we propose two kinds of GLSMs which
have, respectively, 8D hyperKähler manifolds and CalabiYau (CY) 4-folds as their moduli spaces. Moreover, taking an infra-red (IR) limit leads to frozen kinetic termsof vector-multiplets. By integrating them out, a nonlinear
sigma model (NLσM) can be realized in the Higgs branchwhere its kinetic term pulls back the quotient space metric. The latter case is an N =(2,2) model whose Higgs
branch realizes instead a CY 4-fold at IR. It is not Witten’sone1) executing a sympletic quotient because it possesses
key features of newly found 3D N =2 Chern-Simons-mattertheories on M2-branes probing toric CY 4-folds. That is,
†





+

is exactly the vacuum manifold denoted as Cn //G orµ−1 (0)/U (1)r .
Similarly, a hyperKähler quotient space is defined by
Hn ///G (Hn ∼= R4n ) where G(⊂ triholomorphic isometry)is generated by vector fields K’s with LK g = 0 (g: metric) and LK I α = 0. The 2-form complex structure I α(α = 1, 2, 3) is associated with each H described by ds2 =|dq|2 + |dq̃|2 (q, q̃ ∈ C) and transforms as a triplet underSU (2). A quaternion y + y ∈ H with a pure imaginaryy = ui + vj + wk (y, u, v, w ∈ R) consists of two complex numbers: q + q̃j. For n quaternions, r moment maps
associated with G under a charge matrix Qai will read
n


LD =

a = 1, . . . , runder the charge assignment Qai . {φi } parameterizing Cnrepresents the lowest component of N =(2,2) chiral superfield {Φi }. µa ’s are called Fayet-Iliopoulos (FI) parametersand correspond to bringing in r Kähler classes. Eq. (1)modulo the following gauge symmetry
φi ∼ φi eusually F-term conditions (defining a master space) and Dterm ones as a whole give a CY 3-fold just as the story in
4D N =1 SCFT. However, because of one dualized photon
appearing in the theory, the D-term associated with it becomes redundant due to dynamical Fayet-Iliopoulos (FI)parameters, then a 4-fold emerges thereof. Remarkably, we
find these properties definitely show up in our model. The
Lagrangian under consideration is L = LD + LF where

a

a
e2a

2

2

i

∂hi

a

∂φa

2

a
a
(δh(i)
Qai − δt(i)Qai )|hi |2 + |φa |2 − ka x

Da2

The vacuum manifold M is determined by σa = φa =0, Da = 0, dW = 0. We have only (r − 2) linearly independent D-term conditions:a Da = 0,a

‘ ∈ Ker(k),‘ = (1, · · · , 1).

This fact is consistent with that we have a dualized A andleads naturally to a CY 4-fold by definition emerging froma 3-fold. Namely, M = {dW = 0}//C r−1 is a CY 3-foldbecause its derivation is just the same with that of 4D =1
SCFTs on a bunch of D3-branes probing CY3 cones.

References
1) E. Witten, Nucl. Phys. B 403, 159 (1993) [arXiv:hepth/9301042].

RIKEN Accel. Prog. Rep. 43 (2010)

Light-cone gauge string ﬁeld theory in noncritical dimensions†
Y. Baba, N. Ishibashi,∗1 and K. Murakami[String ﬁeld theory, Conformal ﬁeld theory, BRST symmetry]
Light-cone gauge string ﬁeld theory is useful for
deﬁning string theories. From the action, it is possible to deﬁne the amplitudes and calculate them perturbatively, although we should check if they are welldeﬁned. Since it is a gauge-ﬁxed theory, a light-conegauge string theory can be considered in noncriticalspace-time dimensions. As it is noncritical, it does notpossess the space-time Lorentz invariance and corresponds to a string theory in a Lorentz noninvariant
background. In other words, we should be able to ﬁnd
a BRST invariant worldsheet theory containing a nonstandard X ± part.
In this paper, we study the theory for X ± variables,
since it can be used to regularize the string ﬁeld theory.
Dimensional regularization is one of the most powerful regularizations in quantum ﬁeld theory of particles.
It may also be useful in string theory. In particular,
in the light-cone gauge superstring ﬁeld theory, unwanted divergences occur even at the tree level becauseof the transverse supercurrent inserted at the interaction points of the vertices. In order to deal with thesedivergences, in a previous paper1) , we have proposeda dimensional regularization scheme, in which we consider the number of space-time dimensions d to be alarge negative value. We have checked that the resultsof the ﬁrst quantized formalism are reproduced without any counterterms in the four-point case. In orderto proceed further, we need to show that dimensional
regularization preserves the important symmetries of
the theory. If the light-cone gauge string ﬁeld theory
corresponds to a BRST invariant formulation even in
noncritical dimensions, it means that the dimensional
regularization preserves the BRST symmetry.
This study is conﬁned to the case of closed bosonicstring ﬁeld theory in order to avoid technical diﬃculties
involved in the superstring theory and focus on thetree-level amplitudes.
The theory for X ± variables that we propose is a
CFT with the action∫()
1¯ + ∂X −¯ − + ∂X
SX ± = −d2 z ∂X + ∂X
2π)]
d − 26 [ (¯ + ,Γ ln −4∂X + ∂X
+
24∫
24
¯ .
d2 z ∂ϕ∂ϕ
Γ[ϕ] = −(1)
24π
The energy-momentum tensor TX ± (z) obtained fromthe action in eq.(1) is†∗1

d − 26{X + , z} ,(2)12
( 2 +) 2
3+
denotes thewhere {X + , z} ≡ ∂∂XX+ − 32 ∂∂XX+
TX ± (z) = ∂X + ∂X − −Schwarzian derivative. Since the action in eq.(1) contains the terms proportional to 1/∂X + , ∂X + shouldhave a nonvanishing expectation value in order thatthe theory be well deﬁned. For this purpose, we always
consider this theory in the presence of the insertions of+−
the vertex operators e−ipr X (Zr , Z̄r ) (r = 1, . . . , N )
∑N +
+
with
r=1 pr = 0. For functionals F [X ] that do−
not depend on X , it is possible to perform the path
integral which gives
⟨
⟩
N
∏
+
−ip+
X−
r
F [X ]e(Zr , Z̄r )
r=1

]
(
)
]
d − 26 [i¯Γ ln(∂ρ∂ ρ̄) ,(3)∼ F − (ρ + ρ̄) exp −2
24∑Nwhere ρ(z) = r=1 2p+
r ln(z − Zr ) is the Mandelstam
mapping. Roughly speaking, by diﬀerentiating this+equation with respect to p+
N and then setting pN = 0,
we obtain
⟨
⟩
N
−1
∏
−
+
−
−ip+
X
F [X ]X (ZN , Z̄N )e r(Zr , Z̄r ) . (4)[r=1

In this way, we can, in principle, obtain arbitrary correlation functions by considering the right hand side ofeq.(3) to be a generating functional, although the momentum conservation condition somewhat complicatesthis procedure.
From the correlation functions thus obtained, we
can obtain the OPEs for the CFT for X ± variables
and ﬁnd that TX ± satisﬁes the OPE for the Virasoro algebra with a central charge of 28 − d. Thisimplies that by combining the theories for the d − 2transverse coordinates X i and the bc-ghosts with thissystem, we can construct a nilpotent BRST charge.
Thus, we formulate a BRST invariant worldsheet theory that corresponds to the light-cone gauge string theory in d (d ̸= 26) space-time dimensions. We can also
show that the tree amplitudes of the light-cone gaugebosonic string ﬁeld theory can be recast into a BRST
invariant form by using the CFT for X ± variables formulated here.
We shall report the supersymmetric generalizationof the present analyses in a separate paper.
References
1) Y. Baba, N. Ishibashi and K. Murakami: JHEP 10(2009) 035.

Condensed from the article in JHEP 12 (2009) 010
Institute of Physics, University of Tsukuba- 98 -

RIKEN Accel. Prog. Rep. 43 (2010)

Light-cone gauge NSR strings in noncritical dimensions†
Y. Baba, N. Ishibashi,∗1 and K. Murakami[Conformal ﬁeld theory, String ﬁeld theory, Superstring theory]
In the light-cone gauge formulation of string theory, the theory can be considered in noncritical spacetime dimensions. Since the Lorentz invariance is broken in such dimensions, this theory describes a string
in a Lorentz noninvariant background. In a previous
paper1) , we considered the bosonic string theory andidentiﬁed the worldsheet CFT for the longitudinal variables x± that corresponds to such a background.
In this paper, we carry out the supersymmetrizationof the results of Ref. 1). We propose a superconformal
ﬁeld theory for the longitudinal variables x± , ψ ± andψ̃ ± , which correspond to the longitudinal part of thelight-cone gauge NSR string in d (d ̸= 10) dimensions.
We show that the Virasoro central charge of the superconformal ﬁeld theory is ĉ = 12 − d and that we cantherefore construct a nilpotent BRST charge with thetransverse variables and ghosts combined.
In order to supersymmetrize the results of Ref. 1),
it is convenient to use the superﬁeld formalism on
the worldsheet. We introduce the supercoordinatez ≡ (z, θ) and the superﬁelds X ± (z, z̄) which can be
expanded as
X ± (z, z̄) = x± + iθψ ± + iθ̄ψ̃ ± + iθθ̄F ± .

(1)

We propose that the supersymmetric generalization of
the action for the x± CFT1) takes the form∫()
1d2 z D̄X + D− + D̄X − DX +SX ± = −2π
d − 10Γsuper [Φ] ,+8∫8d2 z D̄ΦDΦ ,Γsuper [Φ] = −(2)16π
where D and D̄ denote the supercovariant derivatives,
and the superﬁeld Φ(z, z̄) is deﬁned as()Φ = ln −4(DΘ+ )2 (D̄Θ̄+ )2 ,

Θ+ =

DX +
1

(∂X + ) 2.(3)

The super energy-momentum tensor derived from theaction SX ± in eq.(2) becomes
TX ± (z) =)1(
DX + ∂X − + DX − ∂X +2
d − 10S(z, X +
−
L) .
4
4

+

3

+

2

(4)

+

D Θ
D Θ D ΘHere S(z, X +denotes the suL ) ≡ DΘ+ − 2 (DΘ+ )2
per Schwarzian derivative for the superconformal map++ping z = (z, θ) �→ X +L = (XL (z), Θ (z)), where†∗1

Condensed from the article in JHEP 01 (2010) 119
Institute of Physics, University of Tsukuba- 99 -

XL+ (z) denotes the holomorphic part of the superﬁeld
X + (z, z̄).
In order to make the theory well-deﬁned, eΦ shouldhave a non zero expectation value. As in the bosoniccase1) , we always consider the theory in the presence+−of the insertion e−ipr X (Zr , Z̄r ) (r = 1, . . . , N ), with∑N ++r=1 pr = 0. For the functionals F [X ] which are−
independent of X , one can obtain
⟨
⟩
N
∏
−ip+
X−
+
r
F [X ]e(Zr , Z̄r )
r=1

]
d−10
2
2
i
∼ F − (ρ + ρ̄) e− 8 Γsuper [ln((Dξ) (D̄ ξ̄))] , (5)
2
[

where
ρ(z) =

N
∑
r=1

2p+
r ln(z − Zr ) ,ξ(z) =Dρ
1(∂ρ) 2(z) . (6)Roughly speaking, we obtain
⟨
⟩
N
−1
∏
−
+
−
−ip+
X
F [X ]X (ZN , Z̄N )e r(Zr , Z̄r )

(7)

r=1

by diﬀerentiating eq.(5) with respect to p+
N and thensetting p+
=
0.
More
precisely,
we
have
to
take intoNaccount the momentum conservation condition. In thisway, we can, in principle, derive all the correlation
functions by considering the right hand side of eq.(5) asa generating functional. From the correlation functions
thus obtained, we can deduce the OPEs of the superconformal ﬁeld theory for X ± variables. Using them,
we ﬁnd that TX ± (z) satisﬁes the OPE for the super
Virasoro algebra with central charge ĉ = 12 − d. Bytaking into account the transverse variables X i (z, z̄)(i = 1, . . . , d − 2), the total central charge of the system becomes ĉ = 10. This implies that it is possible toconstruct a nilpotent BRST charge, with the ghost superﬁelds B(z) = β(z) + θb(z) and C(z) = c(z) + θγ(z).
Thus, we formulate a BRST invariant superconformal ﬁeld theory that corresponds to the light-conegauge NSR superstring theory in d (d ̸= 10) space-time
dimensions. We will report the application of this theory to the dimensional regularization of the light-conegauge string ﬁeld theory2,3) in a separate paper.
References
1) Y. Baba, N. Ishibashi and K. Murakami: JHEP 12(2009) 010.
2) Y. Baba, N. Ishibashi and K. Murakami: JHEP 10(2009) 035.
3) Y. Baba, N. Ishibashi and K. Murakami: arXiv:0912.4811.

RIKEN Accel. Prog. Rep. 43 (2010)

Light-cone gauge superstring ﬁeld theory and dimensional
regularization†
Y. Baba, N. Ishibashi,∗1 and K. Murakami[String ﬁeld theory, Superstring, Conformal symmetry]In the light-cone gauge NSR superstring ﬁeld theory1,2) , perturbative expansion of amplitudes involves
divergences even at the tree level. Transverse supercurrents TFLC are inserted at the interaction points zI of
the joining-splitting interaction, and divergences arise
when these supercurrents are close to each other. Similar divergences exist in other superstring ﬁeld theories.
In a previous paper3) , we proposed a dimensional
regularization scheme to deal with these divergences.
In the light-cone gauge, one can deﬁne the theory ind (d ̸= 10) dimensions. By considering d to be largely
negative, we can make the tree-level amplitudes ﬁnite.
By deﬁning the amplitudes for such d, one can obtain
the amplitudes for d = 10 by analytic continuation.
Since what matters is the Virasoro central charge on
the worldsheet, d can also be eﬀectively changed byadding a superconformal ﬁeld theory to that for thetransverse variables X i , ψ i and ψ̃ i . In Ref. 3), we
proposed one such scheme and showed that the resultsof the ﬁrst quantized formulation can be reproduced bysuch a procedure in the case of four-string amplitudes.
In order for the dimensional regularization scheme tobe eﬀective, it should preserve as many symmetries of
the theory as possible. In Refs. 4) and 5), we showedthat the light-cone gauge string ﬁeld theory in noncritical spacetime dimensions corresponds to a BRST
invariant worldsheet theory with the longitudinal variables and the ghosts. Since the BRST symmetry on
the worldsheet is supposed to be related to the gauge
symmetry of the string ﬁeld theory, these results imply
that the dimensional regularization can be carried out
with the gauge symmetry preserved.
In this paper, we would like to propose a dimensional
regularization scheme for the light-cone gauge NSR superstring ﬁeld theory, in which the results of Ref. 5)
can be used. We just formulate the theory in d dimensions and deﬁne the amplitudes as analytic functionsof d. In this paper, we deal with closed string ﬁeld theory and restrict ourselves to amplitudes with only the(NS,NS) external lines. We show that the tree amplitudes can be recast into a BRST invariant form using
the superconformal ﬁeld theory proposed in Ref. 5).
The light-cone gauge superstring ﬁeld theory can bedeﬁned even for d ̸= 10. Starting with the deﬁnition,
the N -string tree amplitudes can be calculated perturbatively. The results can be expressed by using theworldsheet ﬁeld theory for the transverse variables on†∗1

the complex z-plane. Using the superconformal ﬁeld
theory for the longitudinal variables, we can recast theamplitude into the form
∫ [
]
AN ∼
dXdψdψ̃d(ghost) e−S(N −3 [�
]
�
∫ N∏
−3
∏
dz b
dz̄ b̃2(z)×d TI¯ (z̄)
CI 2πi ∂ρ
CI 2πi ∂ ρ̄
I=1
I=1
×
×

N [
∏

cc̃e

−ϕ−ϕ̃

Vr′DDF

r=1

N �
∏

r=1

(r)
zI

×e

dz
DΦ(z)
2πi
d−10 i+16 p+ Xr(

Zr , Z̄r

�

(r)
z̄I

−2 [
)] N∏
I=1

]

X(zI )X̃(z̄I )dz̄D̄Φ(z̄)2πi)(z, z̄) .

(1)

Here S denotes the action of the total system. ρ(z) =∑N
r=1 αr ln(z − Zr ) is the Mandelstam mapping forthe light-cone string diagram. The integration contour CI lies around the propagator between the consecutive interaction points ρ(zI+1 ) and ρ(zI ), and TI =
ρ(zI+1 ) − ρ(zI ) denote the N − 3 complex moduli parameters of the light-cone string diagram. Vr′DDF is
the DDF vertex operator for string r. X(z) denotes
the picture-changing operator, and Φ(z) is a superﬁeld
deﬁned in Ref. 5).
We can show that the amplitude (1) is BRST invariant when d is considered to have a suﬃciently large
negative value. By following the standard procedure,
we can change the positions of the picture-changing
operators to the insertion points of the vertex operators. The resultant amplitudes reproduce the results of
the ﬁrst quantized formulation in the analytic continuation d → 10 without adding any contact interaction
terms as couterterms.
References
1) S. Mandelstam: Nucl. Phys. B69 (1974) 77.
2) S.-J. Sin: Nucl. Phys. B281 (1987) 269.
3) Y. Baba, N. Ishibashi and K. Murakami: JHEP 10(2009) 035.
4) Y. Baba, N. Ishibashi and K. Murakami: JHEP 12(2009) 010.
5) Y. Baba, N. Ishibashi and K. Murakami: JHEP 01(2010) 119.

Condensed from the article in arXiv:0911.3704
Institute of Physics, University of Tsukuba- 100 -

RIKEN Accel. Prog. Rep. 43 (2010)

Vacuum structure around identity-based solutions†
I. Kishimoto and T. Takahashi∗1[Nonperturbative techniques, string ﬁeld theory, D branes]

where the new BRST operator Q′ = QB + adΨa canbe computed explicitly. Let us consider the equationof motion for Sa [Φ], namely, Q′ Φ + Φ ∗ Φ = 0. We
solve it under the Siegel gauge condition b0 Φ = 0. By
multiplying the equation of motion by b0 , we have(3)

where L(a) = {b0 , Q′ }, and we construct numericalsolutions to this equation by an iterative approach withthe level (L, 3L) truncation approximation.
We have constructed two types of solutions. One,denoted as Φ1 , is obtained by smoothly varying a froma = 0. The other, denoted as Φ2 , is obtained bysmoothly varying a from a = −1/2. At a = 0, Φ1
is the conventional tachyon vacuum solution because
Q′ = QB . At a = −1/2, Φ2 can be constructed by iteration, beginning with the initial conﬁguration, which
is given by the nontrivial solution for the lowest truncation. For the obtained conﬁgurations, we have computed the potential height fa (Φ) (≡ −2πg 2 Sa [Φ]/V26 )and the gauge invariant overlap.
For Φ1 , the result of our numerical calculations isplotted in Fig. 1. For L → ∞, the ﬁgure suggeststhat fa=−1/2 (Φ1 ) = 0 and fa>−1/2 (Φ1 ) = −1. Thisimplies that there exists a nonperturbative stable vacuum where a D-brane vanishes, except for a = −1/2.
On the other hand, for Φ2 , our result is depicted as†∗1a)Condensed from the article in Prog. Theor. Phys. 122, 385(2009)
Department of Physics, Nara Women’s University
It is diﬃcult to evaluate gauge invariants for this type of“identity-based” solutions directly. Therefore, we investigated the theory around the TT solution.

level
level (16,48)(16,48)level
level (14,42)(14,42)level
level (12,36)(12,36)level
level (10,30)(10,30)level
level (8,24)(8,24)
level
level (6,18)(6,18)
level
level (4,12)(4,12)
level
level (2,6)
(2,6)

-1
-1

(1)

where I is the identity state and h is a function withthe parameter a (≥ −1/2). Expanding around Ψa , wehave the action
)
(
1
1 1
⟨Φ, Q′ Φ⟩ + ⟨Φ, Φ ∗ Φ⟩ ,(2)
Sa [Φ] = − 2g23L(a)Φ + b0 (Φ ∗ Φ) = 0,

-0.5
-0.5

-0.5
-0.5

0
a

0.5
0.5

Fig. 1. Plots of the potential height fa (Φ1 ) for a ≥ −1/2.

level
level (18,54)(18,54)level
level (16,48)(16,48)level
level (14,42)(14,42)level
level (12,36)(12,36)level
level (10,30)(10,30)level
level (8,24)(8,24)
level
level (6,18)(6,18)
level
level (4,12)(4,12)
level
level (2,6)
(2,6)

22
(Φ22))
ffaa(Φ

Ψa = QL (eh − 1)I − CL ((∂h)2 eh )I,

00

(Φ1))
ffaa(Φ
1

We construct numerical solutions of the theory
around Takahashi-Tanimoto’s analytic solution1) (TTsolution) with a parameter a (≥ −1/2) in open bosonicstring ﬁeld theory and evaluate gauge invariants, thepotential height and the gauge invariant overlap, forthe numerical solutions. Our result provides further
quantitative evidence that for a > −1/2, the TT solution is pure gauge and that for a = −1/2, it represents
a nonperturbative vacuum where a D-brane vanishes.2)
The TT solution Ψa is of the forma)

11

00
-0.5
-0.5

-0.49
-0.49
aa

-0.48
-0.48

Fig. 2. Plots of the potential height fa (Φ2 ) for a ≥ −1/2.
Note that the range of a is much narrower than that ofFig. 1.

in Fig. 2. For L → ∞, the ﬁgure suggests that
fa=−1/2 (Φ2 ) = 1 and fa>−1/2 (Φ2 ) = 0, which implies that there exists a nonperturbative unstable vacuum corresponding to the perturbative vacuum only
for a = −1/2. The behavior of the gauge invariant
overlap is similar to that of the potential height. These
results are consistent with the expectation that the TT
solution for a = −1/2 represents the nonperturbative
vacuum where a D-brane vanishes.
References
1) T. Takahashi and S. Tanimoto: JHEP 0203, 033 (2002).
2) I. Kishimoto and T. Takahashi: Prog. Theor. Phys. 108,591 (2002).

- 101 -

RIKEN Accel. Prog. Rep. 43 (2010)

Lattice formulation of 2D N = (2, 2) SQCD based on B-model twist†
D. Kadoh, F. Sugino,∗1 and H. Suzuki[Supersymmetry, lattice gauge theory]
After a seminal study by Kaplan et al.,1,2) various
lattice formulations of extended supersymmetric gauge
theories have recently been proposed (see Ref. 3 for areview). A common feature of these lattice formulations is that at least one fermionic symmetry Q, which
is a linear combination of supersymmetry charges, ismanifestly preserved even in the case of ﬁnite lattice spacings. This could be possible if Q is nilpotent, Q2 = 0, and the continuum action S is Q-exact
as S = QX. Thus, such a Q is naturally identiﬁed
with a BRST supercharge of topological ﬁeld theory.
4)
In lower-dimensional models, because of this exact
fermionic symmetry Q, one may expect that full supersymmetry is restored in the continuum limit without(or with a little) ﬁne tuning. Recently, the occurrenceof expected supersymmetry restoration in a lattice formulation5) of two-dimensional (2D) N = (2, 2) supersymmetric Yang–Mills theory (SYM) was clearly conﬁrmed6) by means of a Monte Carlo simulation.
From an extended supersymmetric theory, one canconstruct a topological ﬁeld theory by a procedure
called topological twist; this procedure involves deﬁning a new rotational group (twisted rotation) by considering a particular combination of the original spacetime rotation and an internal R-symmetry. The above
BRST charge Q transforms as a scalar under thetwisted rotation. However, if one does not regard thetwisted rotation as a real spacetime rotation, which isthe standpoint we adopt here, the topological twist is
merely the simple relabeling of dynamical variables in
the original supersymmetric action in a ﬂat spacetime.
Nevertheless this procedure is useful to determine theabove Q transformation and a Q-exact form of the action in the continuum theory.
In this paper, we present a new lattice formulationof 2D N = (2, 2) U (k) supersymmetric QCD (SQCD)
with N matter multiplets in the fundamental representation (and no antifundamental multiplet). In 2D
N = (2, 2) theories, a topological twist can be performed in two ways.7) One is the so-called A-model
twist, in which the twisted rotation is deﬁned as a diagonal U (1) subgroup of the product of the original
2D rotation, SO(2) � U (1), and the internal U (1)Vsymmetry. The other is the B-model twist, in which
one considers the diagonal U (1) part of the productof the 2D rotation U (1) and the internal U (1)A symmetry. Here, our objective is to construct a simple
lattice formulation. For this purpose, we adopt the B-model twist picture in which, under Q, left- and righthanded components of the fundamental fermions are
symmetrically transformed. This property of the Bmodel twist helps to obtain a lattice action that is relatively simple compared with the action in the existinglattice formulations8,9) of 2D N = (2, 2) U (k) SQCD,
which are based on the A-model twist.a)
It has been discussed that a 2D N = (2, 2) U (k)SQCD with N fundamental matter multiplets possesses rich physical contents. The low-energy eﬀective
theory would be given by the Grassmannian G(k, N )supersymmetric nonlinear sigma model, in which one
expects the spontaneous chiral symmetry breaking
Z2N → Z2 (the U (1)A symmetry is anomalous andbroken to Z2N ) and the dynamical generation of a mass
gap. In the near future, we hope to use the present lattice formulation to investigate the physical behavior of
in 2D N = (2, 2) U (k) SQCD with N fundamental
multiplets, as has been done for 2D N = (2, 2) SYM
in Refs. 10–13.
References
1) D. B. Kaplan, E. Katz, and M. Ünsal: JHEP 0305,
037 (2003) [arXiv:hep-lat/0206019].
2) A. G. Cohen, D. B. Kaplan, E. Katz, and M. Ünsal:
JHEP 0308, 024 (2003) [arXiv:hep-lat/0302017].
3) J. Giedt: PoS LAT2006, 008 (2006) [arXiv:heplat/0701006].
4) E. Witten: Int. J. Mod. Phys. A 6, 2775 (1991).
5) F. Sugino: JHEP 0403, 067 (2004) [arXiv:heplat/0401017].
6) I. Kanamori and H. Suzuki: Nucl. Phys. B 811, 420(2009) [arXiv:0809.2856 [hep-lat]].
7) E. Witten: Nucl. Phys. B 403, 159 (1993) [arXiv:hepth/9301042].
8) F. Sugino:
Nucl. Phys. B 808, 292 (2009)[arXiv:0807.2683 [hep-lat]].
9) Y. Kikukawa and F. Sugino: Nucl. Phys. B 819, 76(2009) [arXiv:0811.0916 [hep-lat]].
10) I. Kanamori, H. Suzuki, and F. Sugino: Phys. Rev. D
77, 091502 (2008) [arXiv:0711.2099 [hep-lat]].
11) I. Kanamori, F. Sugino, and H. Suzuki: Prog. Theor.
Phys. 119, 797 (2008) [arXiv:0711.2132 [hep-lat]].
12) I. Kanamori and H. Suzuki: Phys. Lett. B 672, 307(2009) [arXiv:0811.2851 [hep-lat]].
13) I. Kanamori: Phys. Rev. D 79, 115015 (2009)[arXiv:0902.2876 [hep-lat]].

a)
†

∗1

Condensed from the article in Nucl. Phys. B 820, 99 (2009)
Okayama Institute for Quantum Physics- 102 -

We could not ﬁnd a lattice discretization of the superpotential that is invariant under our lattice Q transformation.
This restricts the applicability of our lattice formulation.

RIKEN Accel. Prog. Rep. 43 (2010)

SUSY WT identity in a lattice formulation of 2D N = (2, 2) SYM†
D. Kadoh and H. Suzuki[Supersymmetry, lattice gauge theory]
In this study, we clarify some issues related to supersymmetric (SUSY) Ward–Takahashi (WT) identities
in Sugino’s lattice formulation of two-dimensional (2D)N = (2, 2) SU (k) supersymmetric Yang–Mills theory(SYM).1,2) This study is important, because determining whether SUSY is restored in the continuum limit
is the most fundamental issue in non-perturbative lattice formulation of SUSY theories and the best way toobserve the SUSY restoration in the continuum limit
would be to conﬁrm SUSY WT identities.
In this study, we ﬁrst clarify how to derive latticeidentities in Sugino’s formulation that would become
SUSY WT identities in the target 2D N = (2, 2) SYM
in the continuum limit. For this purpose, we devise
an ingenious method to deﬁne a lattice counterpartof the supercurrent—the Noether current associatedwith SUSY—such that its covariance under the global
U (1)A -symmetry can be manifested. Then, on the basis of the formal perturbation theory, we address therenormalization and mixing of composite operators appearing in the identities. The study of the composite operators is quite similar in principle to the standard analysis of the chiral symmetry on the lattice.3)
We can in fact argue that the lattice identities reproduce the SUSY WT identities of the continuum target
theory in the continuum limit without any operator
renormalization/mixing and tuning of lattice parameters. This conclusion is consistent with the expected
SUSY restoration in the eﬀective action of elementaryﬁelds without any ﬁne-tuning, which has been discussed within the perturbation theory in Ref. 1. Thatconsideration on the SUSY restoration in Ref. 1 implies the restoration of the SUSY WT identities in thecontinuum limit was claimed in Ref. 4 only intuitively.
The present analysis remedies this gap.
Our argumentation up to this stage is standard but
formal to some extent. To partially substantiate ourformal argument, we carried out a one-loop calculation that conﬁrmed the SUSY WT identities in theﬁrst nontrivial order of a semi-perturbative expansion(that is similar to the expansion proposed in Ref. 5)
which was justiﬁed for small volume lattices. This result is also complementary with the non-perturbative
numerical conﬁrmation of the SUSY WT identities reported in Ref. 4.
As an interesting application of the lattice SUSY
WT identities, we show that a prescription for thehamiltonian density in this lattice formulation, advocated by Kanamori, Sugino, and Suzuki6,7) in the con†Condensed from the article in Phys. Lett. B 682, 466 (2010)text of spontaneous SUSY breaking, can be justiﬁedby using “current algebra” involving supercurrents andthe hamiltonian density. We have��1∂µ∗ (sµ )i=4 (x) (s�0 )i=1 (y) = i 2 δx,y �Q (s�0 )i=1 (x)� ,a(1)
where ∂µ∗ denotes the lattice backward diﬀerence, sµ (x)is the lattice supercurrent deﬁned above, s�µ (y) is another appropriately-chosen supercurrent, and a is thelattice spacing. The subscript i refers to the spinor
index, and the (i = 4) component of the supercurrent corresponds to a fermionic transformation Q and(i = 1) to a fermionic transformation Q(0) . In thetarget continuum theory, the Q transformation of thetime component of the Noether current associated with
the Q(0) transformation is the hamiltonian density,Q(s�0 )i=1 (x) = 2H(x), as is consistent with the SUSY
algebra, {Q, Q(0) } = −2i∂0 + (gauge transf.). Therefore, it is quite natural to regard the right-hand sideof Eq. (1) as the expectation value of the hamiltonian
density in quantum theory:�Q (s�0 )i=1 (x)� ≡ 2 �H(x)� .

(2)

This is precisely the prescription advocated in Refs. 6
and 7 for the hamiltonian density in the present lattice formulation. Note that Eqs. (2) and (1) showthat �H(x)� is precisely the order parameter of SUSY
breaking; this means that its non-zero (positive) value
implies the massless Nambu–Goldstone fermion in thechannel of the left-hand side of Eq. (1). In Ref. 8, thevacuum energy density of 2D N = (2, 2) SYM has numerically been studied on the basis of this prescription,
indicating no SUSY breaking in this system, contrary
to theoretical conjecture.
References
1) F. Sugino: JHEP 0401, 015 (2004) [arXiv:heplat/0311021].
2) F. Sugino: JHEP 0403, 067 (2004) [arXiv:heplat/0401017].
3) M. Bochicchio, L. Maiani, G. Martinelli, G. C. Rossi,
and M. Testa: Nucl. Phys. B 262, 331 (1985).
4) I. Kanamori and H. Suzuki: Nucl. Phys. B 811, 420(2009) [arXiv:0809.2856 [hep-lat]].
5) T. Onogi and T. Takimi: Phys. Rev. D 72, 074504(2005) [arXiv:hep-lat/0506014].
6) I. Kanamori, H. Suzuki, and F. Sugino: Phys. Rev. D
77, 091502 (2008) [arXiv:0711.2099 [hep-lat]].
7) I. Kanamori, F. Sugino, and H. Suzuki: Prog. Theor.
Phys. 119, 797 (2008) [arXiv:0711.2132 [hep-lat]].
8) I. Kanamori: Phys. Rev. D 79, 115015 (2009)[arXiv:0902.2876 [hep-lat]].

- 103 -

6.

Accelerator

RIKEN Accel. Prog. Rep. 43 (2010)

Conversion of RFQ linac for new RIBF injector
K. Yamada, S. Arai, H. Fujisawa, E. Ikezawa, M. Kase, H. Okuno, N. Sakamoto, K. Suda, Y. Watanabe,
and O. Kamigaito
A new injector (RILAC2)1) has been constructed
at RIKEN Nishina Center for performing independent
RIBF experiments and super-heavy-element synthesis.
RILAC2 consists of a 28-GHz superconducting ECR
ion source2) , a low-energy beam transport with a prebuncher, a four-rod RFQ linac, three drift-tube linac
tanks (DTL1-3)3,4) , a rebuncher between the RFQ and
DTL1, and strong quadrupole magnets between the rf
resonators for transverse focusing. Very heavy ionswith an m/q of 7, such as 136 Xe20+ and 238 U35+ , canbe accelerated up to 680 keV/u in the cw mode andinjected to the RIKEN Ring Cyclotron without charge
stripping. To save construction costs, the RFQ linac
provided by Kyoto University is modiﬁed and used for
RILAC2.
The original RFQ linac was developed by Nissin
Electric Co., Ltd. in 1993 for ion implantation5) . Since
the termination of its acceleration tests in the company, the system has been maintained by the Advanced
Research Center for Beam Science, Kyoto University,
for several years. The RFQ linac can accelerate heavy
ions with an m/q of 16 up to 84 keV/u in the cw modewith an rf frequency of 33.3 MHz. The maximum rf input power was adjusted to be 50 kW(cw). If the RFQ
resonator is so modiﬁed to have a resonant frequency of
36.5 MHz, ions with an m/q of 7 can be accelerated to
100 keV/u for RILAC2 without changing the vane electrodes. The intervane voltage required for RILAC2 is
42 kV, which is less than the originally designed valueof 55 kV. The basic parameters corresponding to the
RFQ linac after the conversion are listed in Table 1; theparameter values were obtained by scaling the originalvalues.
Table 1. Basic parameters corresponding to RFQ linac
Frequency (MHz)Duty (%)
m/q ratio
Input energy (keV/u)
Output energy (keV/u)
Input emittance (mm·mrad)
Vane length (cm)Intervane voltage (kV)
Mean aperture (r0 :mm)
Max. modulation (m)Focusing strength (B)Final synchronous phase (deg.)
Unloaded Q
Shunt impedance (kΩ)
Required rf power (kW)Fig. 1. A 3D model of MWS calculation for RFQ with block
tuner.

serted a block tuner into the gaps between the posts
supporting the vane electrodes. The block reduces
magnetic ﬂux, and consequently, the resonant frequency increases. The size of the block tuner was optimized by 3D electromagnetic calculations using thecomputer code Microwave Studio 2009 (MWS) and rf
measurements using cold-model test pieces made ofaluminum. Figure 1 shows a 3D model of the MWS
calculation. The block dimensions were determined tobe 240 mm × 260 mm × 114 mm. The rf power required to excite the intervane voltage of 42 kV wasevaluated to be 17.5 kW by taking into account 80%
derating of the shunt impedance (63 kΩ) determinedby the MWS calculation. The maximum output power(40 kW) of the ﬁnal ampliﬁer was suﬃcient for operating the modiﬁed RFQ resonator. Note that the shunt
impedance and unloaded quality factor of the original

36.5
100
7
3.28
100.3
200π
225.6
42.0
8.0
2.35
6.785
-29.6
4500 (MWS)
63 (MWS)
17.5 (80%-Q)

For modiﬁcation of the resonant frequency, we in-Fig. 2. Distribution of heat load at an input power of
17.5 kW.

- 105 -

RFQ linac were 77.9 kΩ6) and 5300, respectively.
The heat load distribution was also evaluated by
MWS calculations to decide the cooling conditions.
Figure 2 shows the distribution scaled to an rf input of
17.5 kW. The maximum current density in the block
was 32 A/cm, which was very small. The total heatload estimated for the ﬁve blocks was approximately
2.1 kW. The size of the cooling water channel was sochosen that the ﬂow rate of water was approximately
16 L/min; at this ﬂow rate, the water temperature increases only by 2 o C. The cooling capacity was found tobe suﬃciently high if the value of the shunt impedance
degraded to 70%.

an rf contact provided by coil springs (bal seal). The
water channels in the blocks were connected in series
by copper pipes. Figure 6 shows the internal structure of the RFQ linac after mounting the block tuner
and water pipe. Although the equipments were successfully assembled, apparent leaks were found in thewater channels in some of the blocks, by using a leakhunt. The leak points were repaired in a factory.

Fig. 5. Bottom view of the block tuner.

Fig. 3. 3D view of block tuner.

Fig. 6. Internal structure of RFQ after mounting the block
tuner.

Fig. 4. 3D view of a part of the water inlet for the block
tuner.

The block tuner was made of oxygen-free copper;
three types of blocks were required by the mounting
position. Intricate cutting was carried out on the blockin order to reduce the weight of block to half the original value. The caps of the water channel was sealed byelectron beam welding. Figures 3 and 4 show the 3Dview of the block tuner and water inlet, respectively.
The bottom view of the corresponding block is shownin Fig. 5. The blocks were mounted on a base with2

After the repair, all the equipments were reassembled in February 2010. A low-power test was performed to evaluate the rf characteristics, and the resonant frequency was found to be changed to 36.5 MHz
successfully. Rf ampliﬁers, low-level circuits, and acontrol system for RILAC2 were installed at the appropriate positions in February 2010. The main bodyof the RFQ has been moved to the AVF cyclotron vault
in May 2010. Immediately after preparing the coolingwater, vacuum pumps, and electric cables on the RFQ
resonator, a high-power test will be performed.
References
1) O. Kamigaito et al., PASJ3-LAM31, Sendai, Aug. 2006,
WP78, p502 (2006).
2) T. Nakagawa et al., Rev. Sci. Instrum. 79, 02A327(2008).
3) K. Yamada et al., in this report.
4) K. Suda et al., in this report.
5) H. Fujisawa, Nucl. Instrum. Meth. A 345, 23 (1994).
6) H. Fujisawa et al., Proc. 7th Int. Symp. on Advanced
Energy Research, Takasaki, Mar. 1996, p.436 (1996).

- 106 -

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Design and construction of drift-tube linac no.1 for RILAC2
K. Yamada, K. Suda, N. Sakamoto, S. Arai, E. Ikezawa, M. Kase, H. Okuno, and O. Kamigaito
A new additional injector (RILAC2)1) has been
constructed at the RIKEN Nishina Center so thatRIBF experiments and synthesis of super-heavy element can be carried out independently. The RILAC2 consists of a 28-GHz superconducting electroncyclotron-resonance ion source (ECRIS)2) , a lowenergy beam transport (LEBT) with a pre-buncher, afour-rod radio-frequency quadrupole (RFQ) linac3,4) ,three drift-tube linac tanks (DTL1-3), a rebuncher between the RFQ and DTL1, and strong quadrupole
magnets that were placed between the rf resonators forthe transverse focusing. Very heavy ions with mass-tocharge ratio (m/q) of 7, such as 136 Xe20+ and 238 U35+ ,are accelerated up to an energy of 680 keV/u in the
cw mode and injected into the RIKEN Ring Cyclotron
without charge stripping. This report describes thedesign and construction of DTL1.
The DTL1 consists of a quarter-wavelength coaxialcavity resonator, which has nine drift tubes with stems
and two drift tubes at the end (10 gaps). The aperture of the drift tube has a radius of 17.5 mm, andthe gap length is 20 mm. The DTL1 is operated at
a gap voltage of 110 kV with a radio frequency of
36.5 MHz and it can accelerate ions from 100 keV/u
to 220 keV/u. In order to optimize the rf characteristics and to determine the cavity dimensions, 3D electromagnetic calculation was performed using the computer code Microwave Studio 2009 (MWS). Figure 1
shows a DTL1 model used in the 3D electromagnetic
calculation. The length of the stem was optimized toreduce the asymmetry of the electric field distribution
between the gaps. The distribution of rf-power dissipation in the cavity was also evaluated by the MWS calculation to determine the amount of cooling required.
The basic properties of DTL1 are listed in Table 1.

Fig. 1. A DTL1 model used in the 3D electromagnetic calculation; the model includes a tuner and coupler.

In order to reduce the construction cost and thespace occupied by the equipments, a direct coupling

Table 1. Basic properties of DTL1

Frequency (MHz)Duty (%)
m/q ratio
Input energy (keV/u)
Output energy (keV/u)
Cavity diameter (m)Cavity height (m)Gap number
Gap length (mm)Gap voltage (kV)
Drift-tube aperture radius (mm)Peak surface field (MV/m)
Synchronous phase (deg.)Max. power of amp. (kW)

DTL1
36.5
100
7
100
220
0.8
1.32
10
20
110
17.5
8.2
-25
25

scheme was adopted for the rf amplifier. A plate electrode of a 4CW50000E vacuum tube was directly connected to the capacitive coupler, which was mounted
on the cavity. The load impedance of the vacuum tube
can be adjusted by changing the position of the coupler electrode. When the coupler and vacuum tube
were mounted on the cavity, the resonant frequency
decreased because of their series/parallel capacitance.
Thus, we had to set the target frequency of the cavity
such that this decrease in the resonant frequency wascompensated. The decrease in the resonant frequency
was estimated by comparing the result of MWS calculation with the measurement results obtained using
DTL35) with a 50-Ω coupler. Since the DTL3 was obtained by modifying a decelerator resonator that wasdeveloped for a Charge-State-Multiplier system6) , wewere able to use it for the comparison. Finally, thecavity length of DTL1 was determined to actualize thetarget frequency of 36.725 MHz.

Fig. 2. Capacitive coupler for DTL1. φ 170 mm electrodeis attached.

- 107 -

The coupler of DTL1 was designed such that the1

load impedance could be adjusted to approximately
1000 + j0 Ω with using vacuum tube. The default
position and radius of the coupler electrode were determined by the MWS calculation using a frequencydomain solver. The coupler for DTL1 is shown in
Fig. 2.

1300 Ω by moving the coupler electrode over a distanceof 40-mm.

Fig. 5. Electric-field distribution of DTL1 along the beamaxis.

The electric-field distribution along the beam axis
was measured using a φ 12 mm TiO2 bead by the perturbation method. The results of phase variations areplotted in Fig. 5. The shunt impedance was evaluated from the integral of the result, and the required rf
power was determined. The rf characteristics of DTL1
are listed in Table 2.
A high-power test was performed with a load
impedance setting of 1000 Ω. After one day of conditioning, the rated voltage of 110 kV was successfully
achieved.
The DTL1 was installed in the AVF cyclotron vault
in February 2010. Further conditioning and tests is
now in progress.

Fig. 3. Exterior of DTL1

Table 2. Rf characteristics of DTL1

Frequency (MHz)
Unloaded Q
Shunt impedance (MΩ)
Effective shunt imp. (MΩ/m)Required rf power (kW)Fig. 4. Frequency response of DTL1 as a function of trimmer position.

The construction of the DTL1 was completed in January 2010, and low-power and high-power tests were
performed immediately. Figure 3 shows the exterior of
DTL1 used in test measurements. The results of the
low-power test measurements carried out using a network analyzer are indicated in Fig. 4. The frequency
response as a function of trimmer position is plotted in
the upper panel of Fig. 4. The lower panel presents thequality factors. As shown in the figure, an operation
frequency of 36.5 MHz was achieved at the trimmer
position of 68 mm by using a φ 170 mm direct coupler. The load impedance can be adjusted from 600 to2- 108 -

Calculated
35.83–37.13
17500
1.13
163
5.3

Measured
35.64–36.87
13000
0.94
135
6.5

References
1) O. Kamigaito et al.: PASJ3-LAM31, Sendai, Aug. 2006,
WP78, p. 502.
2) T. Nakagawa et al.: Rev. Sci. Instrum. 79, 02A327(2008).
3) H. Fujisawa: Nucl. Instrum. Meth. A 345, 23 (1994).
4) K. Yamada et al.: in this report.
5) K. Suda et al.: in this report.
6) O. Kamigaito et al.: Rev. Sci. Instrum. 76, 013306(2005).

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Design and Construction of Drift Tube Linac Caivties No. 2 and 3
for RILAC2
K. Suda, S. Arai, Y. Chiba, O. Kamigaito, M. Kase, N. Sakamoto, and K. Yamada
A new injector RILAC2 for RIKEN RI-Beam Factory is under construction1) (Fig. 1). The injector istubes, a non-50 Ω capacitive coupler, and a trimmer(fine frequency tuner). The modification of CSM-D1
to DTL3 was performed as follows. Firstly, the original
drift tubes and stems were replaced with those specifically designed for DTL3. The frequency of CSM-D1

Fig. 1. Schematic view of the new injector RILAC2.

designed to accelerate very heavy ions such as 238 U35+
and 136 Xe20+ up to 680 keV/u for injection to the
RIKEN Ring Cyclotron. The injector consists of an
superconducting ECR ion source, a low-energy beamtransport line, an RFQ linac, three drift tube linac(DTL) tanks, and a high-energy beam transport line.
The structure of the DTL tanks is based on that ofa quarter-wavelength resonator. The inner diameter
ranges from 0.8 to 1.3 m. The DTL tanks are designed
to be operated at a fixed RF frequency of 36.5 MHz.
The design parameters are shown in Table 1. The
Table 1. Design parameters for DTL2 and DTL3.
Resonator
Frequency (MHz)Duty (%)
Mass-to-charge ratio
Input energy (keV/u)
Output energy (keV/u)
Diameter (m)Height (m)Gap number
Gap length (mm)Gap Voltage (kV)
Drift tube aperture (mm)Peak surface field (MV/m)
Synchronous phase (◦ )Input power (100% Q: kW)
Power amp. (Maximum: kW)

DTL2
36.5
100
7
220
450
1.1
1.429
10
50
210
17.5
9.4
-25
13.4
40

DTL3
36.5
100
7
450
680
1.3
1.890
8
65
260
17.5
9.7
-25
15.4
40

first two tanks (DTL1 and DTL2) have been newly
constructed while the decelerator tank developed for
Charge-State-Multiplier system2) (CSM-D1) is modified to obtain the third tank DTL3. For the purpose tosimplify and minimize the size of an final RF amplifier
and to reduce construction cost, the amplifier was directly coupled to the tank. In this report, we describe
the design and construction of DTL2 and DTL3. The
schematic view of DTL3 is shown in Fig. 2.
First, DTL3 was designed. DTL3 has eleven drift

Fig. 2. Schematic view of DTL3. It has eleven drift tubes,
a non-50 Ω capacitive coupler, and a trimmer.

can be varied from 36 to 76.4 MHz by changing theposition of a movable shorting plate. In order to install the modified tank in the AVF hall, it was necessary to reduce the tank height by removing the shorting plate as well as its drive mechanism, cutting theinner and outer cylinders, and attaching a new fixed
top plate with a flange which supports inner cylinder.
Therefore, low-power tests were performed in order toestimate the decrease in the resonant frequency due
to the directly coupled amplifier and to determine thetank height. The 50-Ω coupler originally attached to
CSM-D1 was used for this measurement. The lengthof the coaxial line was 1700 mm. Coupler plate oftwo sizes (φ 115 and 210 mm) were used. The optimum input impedance to the tank was estimated to
be 700 Ω on the basis of the analysis of the operation of the tetrode 4CW50000E, which was used in
the final power amplifier. This impedance needs tobe matched when the tetrode is connected in parallel, the capacitance of which is approximately 55 pF.
In the case of the coupler plate of φ 115 mm, the input impedance was matched to 50 Ω when the coupler
was at a position of 456.2 mm from the center of thetank. When the coupler plate of φ 210 mm was used,matching condition for 50 Ω was not found within the
stroke of the coupler. The coupling condition for direct coupler was estimated by transforming the measured data using f-matrix calculations to the case of ashorter 50 Ω coaxial line (529.8 mm), which matches
the geometry of the direct coupler. According to theestimation, the impedance will be matched to 700 Ω atthe coupler position of around 300 mm from the cen-- 109 -

1

Fig. 3. Electric field distribution of DTL3. The data areplotted as solid circles. A calculation result by MWS isshown as a solid line.

ter of the tank, and the decrease in frequency is withina range of 175 kHz and 275 kHz (average 225 kHz).
On the other hand, the flange below the top plate increases the frequency by +125 kHz from the calculationof the Eigenmode solver of the CST Microwave Studio (MWS). Therefore, the target frequency was fixedat 36.6 MHz (= 36.5 + 0.225 − 0.125). Then, the tankheight was determined to be 1.890 m. Figure 3 shows
the measured electric-field distribution of DTL3. The
deduced shunt impedance is 1.72 MΩ, which is 80%of the value calculated using MWS. An average gap
voltage of 260 kV can be obtained if an input power of
19.6 kW is fed.
After the tank height was determined, a capacitive
coupler was designed. This coupler consists of a non50 Ω coaxial cylinder and a plate at the end of an innercylinder. The position of the inner cylinder can be adjusted manually to ±20 mm in order to tune the input
impedance. The maximum diameter of the coupler
plate has to be less than 213 mm because of the sizeof the flange. In order to be able to adjust the input
impedance by changing the diameter of the plate, thecoupler position was set to be 250 mm from the centerof the tank (50 mm lesser than previous position). The
diameter of the coupler plate was then determined to
be 130 mm from calculations using MWS. However,when the coupler and tetrode were attached, the input impedance was found to be lower than expected.
Therefore, the actual diameter of plate was increased
to 135 mm. The frequency of the tank was decreasedby 288 kHz (Fig. 4). The cooling powers needed for thetank and coupler were determined by taking into consideration the calculated thermal distribution on thecondition of the maximum output of the amplifier.
Based on the experience of designing DTL3, DTL2
was designed by only calculations. Figure 5 shows aschematic view of DTL2. The length of stems waschanged from 200 mm (original) to 150 mm in orderto improve the deviation of gap voltages3) . The deviation was reduced from 6.4% to 4.6%. The tank heightwas determined, as in the case of DTL3, by taking into
account the change in frequency, but without that due

2- 110 -

Fig. 4. Resonant frequency of DTL3. The measured values
without and with coupler are denoted by closed andopen circles, respectively. The decrease in the frequency
was 288 kHz.

Fig. 5. Schematic view of DTL2. It has nine drift tubes,
a non-50 Ω capacitive coupler, and a trimmer. The
shorting end is placed in the vertically down direction,
which is the opposite of the case of DTL3, owing to ashorter height of cavity and a deeper (+40 cm) floor
level.

to the flange. This is because the flange was taken
into account in the calculations using MWS. Therefore, the target frequency was set to be 36.725 MHz(= 36.5 + 0.225), and the tank height was determined
to be 1.429 m. The coupler position was determined
as follows. At first, the coupler position which results
in an impedance of 50 Ω was determined. When aplate of φ 115 mm was used, and the actual Q-value
was assumed to be 70% of that obtained by calculations, the position was estimated to be 420 mm fromthe center of the tank. Then, as in the case of DTL3,
this position was changed to obtain an impedance of
700 Ω. The diameter of the plate was determined to
be 140 mm by a low-power test.
A high-power test of DTL3 and DTL2 were performed in December 2009 and January 2010, respectively, and the desired gap voltages were successfully
obtained. These tanks as well as DTL1 will be installedin the AVF hall in February 2010.
References
1) O. Kamigaito et al.: Proc. PASJ6 (2009), p. 38.
2) O. Kamigaito et al.: Proc. LINAC’98 (1998), p. 603; O.
Kamigaito et al.: Rev. Sci. Instrum. 76, 013306 (2005).
3) K. Yamada et al.: In this report.

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Construction of a new cavity for the double-rebuncher system for
RRC
N. Sakamoto, K. Suda, K. Yamada, M. Kase, and O. Kamigaito
A new cavity has been designed and built to replace
one of the cavities of the double rebuncher system for
RRC (RIKEN Ring Cyclotron). The present S6 cavity
1), which is located close to RRC, was originally usedas the third harmonic rebuncher for the harmonic 5
operation (i.e. the rf frequency of the RRC is the fifth
harmonic of beam revolution freauency) in the case of
AVF injection. Therefor its frequency band of 60 to
90 MHz does not match to the beams form rilac whose
freqency is 18 to 38 MHz.
The specifications of the new cavity are summarizedin Table.1. The range of frequencies from 36.5 to 76.4
MHz is the second harmonic of the beam frequency
from the injector RILAC. A peak voltage of 20 kV
at 36.5 MHz is set in order to achieve point-to-point
conversion from the exit of the RILAC to the injection point of the RRC in the operation of 238 U35+
beam acceleration with anfinal energy of 345 MeV/u.
Table 1. Specifications of new rebuncher.
frequency
β · λ/2
gap
no. of gap
cavityvoltage
amplifiertrimmer

36.5∼76.4 MHz
156 mm20 mm
4
λ/2
20 kV/gap(36.5 MHz)
1 kW
∆f
= ±0.5%fFig. 2. Resonant frequency as a function of the position of
the shorting plate is plotted for two tuner positions.

onant frequency can be varied by moving a shorting
plate. In order to achieve wide frequency range, for a
low frequencies between 36.5 and 40 MHz, a pair of capacitive tuners is used to make the resonant frequency
lower as shown in Fig. 2. The rf power is fed to thecavity by a 50 Ω coaxial waveguide of WX39D. The
coupling is a capacitive one and the coupling β can bevaried by changing the position so as to the impedanceis matched to 50 Ω. A capacitive trimmer installed at
the opposite side of the coupler changes the resonant
frequency by ±0.5%. The parallel shunt impedance

The structure of the cavity (Fig.1) has been optimized
by using a 3D electromagnetic-field-calculation codes
MWS. The present cavity is a λ/2 cavity whose resFig. 3. Results of low-power tests. The open and closed
circles represent the results obtained when the tuner
was 220 mm from the drift tube support, respectively.

(Rs) was measured by using a perturbation method.
The perturbation bead was a ceramic ball (K-140 Kyocera, r = 138) with a diameter of 12 mm, which gives
a maximum phase shift of 74◦ . The measured Q, Rs,
and wall loss of the cavity are plotted in Fig.3. The Q
values are 60∼80% of the calculated values.
A Power test is underway and the installation of thecavity is planned in February 2010.
References
1) A. Goto et al.:RIKEN Accel. Prog. Rep. 23(1989).
Fig. 1. Schematic of new rebuncher cavity.The scale is presented in the unit of mm.

- 111 -

1

RIKEN Accel. Prog. Rep. 43 (2010)nsrcn f e R2 R en nc 2 ne†









        
                       
    
       


                     
         
                
     
              
          

       
     


      


           
 

       

        



        




          

        

 

                    
       
        
      
      

            
             
            
            

References


42         
42         
         
 
 
42         
 - 112 -



- 113 -

RIKEN Accel. Prog. Rep. 43 (2010).

Production of highly charged U and Au ions from new RIKEN
superconducting ECR ion source with sputtering method
Y. Higurashi, J. Ohnishi, T. Nakagawa, T. Aihara*, M. Tamura*In the autumn of 2009, it was required to produce few tenof microamperes of U35+ beam from the newsuperconducting ECR ion source in order to increase the U
beam intensity for producing radioisotope beams. To meetthis requirement, we performed a test experiment before theproduction of the U beam from the new RIKEN
superconducting ECR ion source1,2) with sputtering method.
Figure 1 shows a photograph of the RF injection side of theion source used in the sputtering method. As shown in thisfigure, we set a metal rod at the tip of a support rod. The
position of the metal rod was remotely controlled with anaccuracy of 0.5 mm. For sputtering, the metal rod was
supplied with high negative voltage (~several kV) . Oxygengas was used as the ionized gas.

Fig. 2. Charge-state distribution of Au ions. Ion source wastuned to produce Au30+ ions.

Fig.1. Photograph of RF injection side of the ion source
used in sputtering method.
Before producing the U beam, we performed a test
experiment in which highly charged Au ions were produced
from a Au rod. Figure 2 shows the charge-state distributionof the Au ions. The ion source was tuned to produce Au30+
ions. The maximum magnetic field strength at the RF
injection side (Binj), the minimum strength of mirror themagnetic field (Bmin), the maximum magnetic field strength
at the beam extraction side (Bext), the radial magnetic fieldstrength at the inner surface of the plasma chamber wall(Br), gas pressure, RF power (18 GHz), and extraction
voltage(Vext) are listed in the figure. Figures 3a) and 3b)
show beam intensity as a function of the rod position andbias disc voltage, Rod position is defined as the distance
between the metal rod and the wall of the RF injection side(see Fig.1). Using this sputtering method, we produced
Au30+ ion beam with beam intensity ~30eµA .
＊SHI Accelerator Service Ltd.

Fig. 3. Beam intensity as a function of a) rod position and b)
bias disc voltage.
After successful Au beam production, we tried to produce
highly charged U ions by using the same method. Figure 4- 114 -

shows the charge-state distribution of the U ions. The
ion-source conditions are listed in Fig. 4. The ion source
was tuned to produce U35+ ion beam. The maximum beam
intensity of 15 eµA was obtained on the RF power of 850
W(18 GHz). Using this method, we provided a continuous
supply of U35+ beam (average beam intensity; 12 eµA) forthe experiments for one month.

Fig. 4. Charge-state distribution of U ions.
References
1)T. Nakagawa et al.: Rev. Sc. Instrum. 79, 02A327 (2008)2)T. Nakagawa et al.: accepted for publication in Rev. Sci.
Instrum.

- 115 -

RIKEN Accel. Prog. Rep. 43 (2010).

Status of the new superconducting ECR ion source for RIKEN RIBF

Y. Higurashi, J. Ohnishi, T. Nakagawa, T. Aihara*, M. Tamura*, A. Uchiyama*, H. Okuno, K. Kusaka, M. Kidera, E. Ikezawa,
M. Fujimaki, Y. Sato, Y. Watanabe, M. Komiyama, M. Kase, A. Goto, O. Kamigaito, and Y. Yano
Since the middle1990s, RIKEN has undertaken theconstruction of a new accelerator facility called the Radio
Isotope Beam Factory (RIBF)1) and successfully produced
345 MeV/u U beam (~0.4 pnA on target) in 2007.2) For the
RIBF, a primary beam intensity of 1pµA on target isrequired; hence, we have to increase the beam intensity.
Hence, in the summer of 2007, we started the constructionof a new superconducting ECR ion source (SC-ECRIS)
with the optimum magnetic field strength to achieve an
operational microwave frequency of 28 GHz. In the end of
2008, we achieved a magnetic field strength value that was
102% of the designed value.3) In the spring of 2009, the
SC-ECRIS produced the first beam with 18 GHz
microwaves. After obtaining the first beam from the ion
source, we performed various test experiments using 18
GHz microwaves, the experiments were aimed at increasing
the beam intensity of highly charged heavy ionsFig. 1. Beam intensity of Ar11+ and Ar12+ beam as a functionof RF power
The detailed structure of the ion source is described in
ref.4. Figure 1 shows the beam intensity of Ar11+ and Ar12+
beams as a function of RF power. The maximum magnetic
field strength at RF injection side (Binj) and beam-extraction
side (Bext) and the minimum strength of the mirror magnetic
field (Bmin) are listed in this figure. The magnetic fieldstrength at the surface of the plasma chamber (Br) is also
shown. We obtained ~300 eµA of Ar11+ beam and 180 eµAof Ar12+ beam at an RF power of ~800 W.
The unique feature of this ion source compared to theother superconducting ECR ion sources is that it has six
solenoids that are used to produce the axial mirror magnetic
field. Using the six solenoids system, we can change themagnetic field gradient in the resonance zone and the ECR
surface size independently. From model calculations5) , it ispredicted that the magnetic field gradient in the resonance＊zone and ECR surface size strongly affect the beam
intensity of highly charged heavy ions; however, the effectof the field gradient and ECR surface size on beam intensity
has not yet been verified experimentally. To clarify theeffect of these two factors on beam intensity, we measured
the beam intensity of highly charged heavy ions as afunction of the magnetic field gradient for several ECR
surface sizes. Figure 2 shows the beam intensity of Xe24+
beam as a function of the average magnetic field gradient in
the ECR zone for several ECR surface sizes. The average
field gradients were calculated by using the OPERA 3D
code . The extraction voltage and RF power were fixed at
15 kV and 600 W, respectively. The main magnetic feildparameters are listed in Fig. 2. It is apparent that the beam
intensity increases as the field gradient decreases and the
ECR surface size increases. A detailed analysis is inprogress

Fig. 2. Beam intensity of Xe24+ beam as a function of
average magnetic field gradient in the resonance zone forseveral ECR surface sizes
References
1)Y. Yano.: Nucl. Instrum. Methods B2611009(2007)2)N. Fukunishi et al.: Proc. PAC’09 in press
3)J. Ohnishi et al.: RIKEN. Prog. Rep. 42 115(2009)4)T. Nakagawa et al.: Accepted for publication in Rev. Sci.
Instrum.
5)A. Girard et al.: Rev. Sci. Instrum. 751 381(2004)

SHI Accelerator Service Ltd.

- 116 -

RIKEN Accel. Prog. Rep. 43 (2010).

Installation of new superconducting ECR ion source in the Cockcroft-Walton
high-voltage terminal
J. Ohnishi, Y. Higurashi, T. Nakagawa, T. Aihara,＊1 M. Tamura,＊1 and O. Kamigaito

A 28-GHz ECR ion source is currently being constructedat the RIBF in order to obtain high-intensity beams ofhighly charged ions like U35+.1) One of the most importantelements of the ECR ion source is its superconducting
magnet. This magnet consists of six solenoids and a set of
sextupole coils. Its design and construction was difficult
because of its complex structure and high magnetic fields.
Its construction began in October 2007 and was completed
successfully in December 2008.2) It was planned that an ion
source that uses this superconducting magnet will beassembled and tested by using two existing 18-GHz
microwave sources because a 28-GHz source had not been
constructed in 2009. Nevertheless, the new source was
expected to generate currents that would be ten times-higher
than the current generated by the existing 18-GHz ECR ion
source because of its strong magnetic field and large plasma
volume. Therefore, it was decided that the new ECR ion
source will be installed as a RILAC source and uranium
beams will be supplied to the RIBF.3)
For this purpose, we planned to install the new ion source
onto the Cockcroft-Walton high voltage terminal that wasused previously and inject the uranium beams into the

RILAC at the energy of 127 kV per charge but not via the
RFQ linac. The main reason for this was that the extraction
voltage of the ion source needs to be increased from thepresent considerably low value of 5.6 kV in order to be
injected into the RFQ.
We built an additional stage for the high-voltage terminal
in order to increase its area from 16 m2 to 31 m2. On theother hand, the insulation distance to the wall was decreased
from 2.5 m to 0.5 m because the new terminal voltage islower than the previous value which was 450 kV. Although
the old terminal was supported on nine double-layer
porcelain insulators with a length of 1150 mm, for the newterminal, the support structure was altered such that it
consisted of 17 single-layer insulators; this was done
because the total load on the terminal exceeds 15 t when theterminal voltage is low. Further, we constructed a simple
room in the terminal in order to limit the area where
uranium may scatter.
Figure 1 shows the plan view of the high-voltage
terminal. The magnetic elements in the low energy beamtransport (LEBT) on the terminal4) include a solenoid, ananalyzing bending magnet (BM), and two steering magnets

100-kV Stage
to RILAC
QM

Accel Profile
Tube MonitorST

注
12：
コ
イ
部
冷
却
手
は
の
図
・
継
他
を
転用
し
た
め
細
部
異
な
，
は
る
ボ
ル
ト
サ
ズ
の
認
必
イ
確
要

Faraday
Cup

LifterTransformer
100 KVABM

Slit

PS solenoid
PS ST
Vacuum/Monitor
Controller

ST

PS
Transformer Cockcroft

Solenoid
Generator
Superconducting (no use)
Ion source
AC distributor

Ion source
driverVacuumPS Superconducting
Coils
RF, Gas Injector
CryostatController
He
Compressor

Wall

PS BM PS
18-GHz RF Extended StagePS
18-GHz RF
AC distributor

7.6 m

Fig. 1. Plan view of the Cockcroft-Walton high-voltage terminal.
＊1

SHI Accelerator Service Ltd- 117 -

(ST) for horizontal and vertical directions. The analyzing
magnet, whose design is the same as that in the 28-GHz
superconducting ion source VENUS at LBL, has sextupole
field components to reduce the abbreviation generated bythat the magnet has a large aperture.5) The beam optics is adouble-focus system and the focus point is 1.0 m
downstream of the exit point of the BM. A horizontal slit islocated at the focus point and beam profile monitors arelocated 0.1 m and 0.3 m downstream of the slit. A Faraday
cup is placed immediately before an accelerating tube.
Electric power and cooling water for the devices on thehigh-voltage terminal are listed in Table 1. The electric
power is supplied only through a 100-KVA insulatedtransformer. The total power shown in the table exceeds thecapacity of the transformer because each value is given by
the full power. Cooling water at 100 L/min is supplied
through rubber hoses with a size of 32A for electric
insulation from the existing cooling water system.
After the superconducting magnet was installed in thehigh-voltage terminal in December 2008, the constructionof the simple room, alignment of the beam line, cabling andpiping were carried out in January and February 2009. The
application test of the high-voltage terminal was performedon February 18. Initially, some arcs were observed; this was
because an iron plate placed temporary on the ceiling andAC lines floated electrically from the terminal floor. The
arcs disappeared as soon as the plate and AC lines weregrounded to the floor. Further, some coronas were observed
at some corners of the building; these were ignored since
they did not seem to affect the beam operation. The leakage
current was 1.7~2.0 mA at 110 kV and its major cause waspresumed to be the electric conduction through the water
hoses.
Precooling of the superconducting coils and filling of
liquid helium in the cryostat was carried out in March.
During precooling, the magnet was cooled using evaporated
nitrogen gas at a low temperature before liquid nitrogen waspoured over it; this was done to reduce the thermal stresses
due to the large difference between the temperature of themagnet and that of liquid nitrogen. This precooling was
carried out for four days (no operation were performed atnight), and 1200 L of liquid nitrogen were used. After theprecooling, 700 L of liquid helium was poured and its 330 L
was stored. The stored liquid helium is maintained by threehelium GM refrigerators.6) Two of these can cool up to 10 K
(SUMITOMO RDK408S), while the other can cool up to 4
K (RDK408D2). Further GM-JT refrigerator (V316SLCR,
4 W @ 4 K) is equipped to cool the heat load due tobremsstrahlung
fromion-source
plasma.
The
superconducting magnet was excited successfully at 90% of
the design current on March 17. This current level issufficient for an 18-GHz operation. Subsequently, thechambers, a vacuum system, an rf system and beam
monitors were assembled, and the first beam of oxygen was
extracted from the ion source on May 11. Then, the aging
and the investigation of the ion source began. The operationof the ion source is described in another report.7) The firstacceleration test in the RILAC was performed using Xe20+

Table 1. Summary of electric power and cooling waterrequired for the devices in the high-voltage terminal.
Number
18GHz RF source
Superconducting magnet
Analyzing magnet
Solenoid coilSteering magnet
He refregerator/compressor
Ion source body
Vaccum system
Beam Diagnostic
Cryostat controller
Total

2
1
1
4
4

Electric
Power
(kW)
30
12
20
15
2
40
1
3
1
1

Cooling
Water(L/min)

125

90

15
15
40
15
5

beam on July 26.
The ion source generated much stronger bremsstrahlung
when compared to that generated by the old one. This
reason seems to be because the electron temperature of theplasma is higher than that in the old one. We had todecrease the X-ray leakage to the outside of the RILAC
building. The distances from the ion source areapproximately 5 m to the east and west wall, 7.5 m to thenorth wall, and 5 m to the roof. In order to maintain theleakage within the allowed limit (2.5 μSV/h), 36 lead
blocks each with a thickness of 100 mm were laid on theaxis and two layers of lead plates each with a thickness of 5
mm were fixed on the north side of the yoke. The total
weight was approximately 1.5 t. Further, the roof area was
set to a controlled area.
In October, a production test of Au ions was carriedout after preparation for the sputtering method. We received
approval for handling nuclear fuels on October 30, anduranium beams were produced successfully on November 2.
The U35+ beam current was approximately 10 μA. The U35+
beams were accelerated in the RILAC on November 13 andsupplied to RIBF experimenters from November 26. The
beam current from the new ion source was approximately
five-times higher than that from the old one.
The construction of the 28-GHz microwave source wascompleted in March 2010. Furthermore, a new injector
called RILAC II which consists of an RFQ linac and DTLs
is also under construction. Therefore, we are planning tomove the ion source to a newly constructing building andprovide it upon completion of its construction as the
28-GHz ECR ion source for the RILAC II in 2010.
References

1) T. Nakagawa et al.: RIKEN Accel. Prog. Rep. 42, ix (2009).
2) J. Ohnishi et al.: RIKEN Accel. Prog. Rep. 42, 155 (2009).
3) O. Kamigaito et al.: Proc. the 11th Int. Conf. Heavy Ion Accel.
Technology 21 (2009).
4) Y. Sato et al.: RIKEN Accel. Prog. Rep. 42, 148 (2009).
5) C. M. Lyneis et al.: AIP Conf. Proc. 600, 219 (2001).
6) J. Ohnishi et al.: Proc. 2009 ann. Meet. Particle Accel. Soc. Jpn.
635 (2009).
7) Y. Higurashi et al.: in this report.

- 118 -

RIKEN Accel. Prog. Rep. 43 (2010)

Design of Low Energy Beam Transport in New RIKEN Injector
Y. Sato,∗1 M. Fujimaki, N. Fukunishi, A. Goto, Y. Higurashi, E. Ikezawa, O. Kamigaito, M. Kase, T. Nakagawa,J. Ohnishi, H. Okuno, H. Watanabe, Y. Watanabe, and S. Yokouchi
The RIBF project needs high-intensity uranium-ion
beams. We are constructing a new injector RILAC2,
which would provide beams with several hundred times
higher intensity1) . The RILAC2 consists of an electron cyclotron resonance ion source (ECRIS), an analyzing bending magnet (BM), a buncher, a radio frequency quadrupole (RFQ), a re-buncher, and 3 DTLs2)(Fig. 1). The 28 GHz superconducting ECRIS3) andthe DTLs have been newly developed4) .Improvements
were made to the RFQ, which was originally being operated at the Kyoto University. The buncher will be
operated at the ﬁrst harmonic, 18.25 MHz. The RFQ,
the re-buncher, and the 3 DTLs will be operated at
the second harmonic, 36.5 MHz. The RILAC2 will be
operational in winter 2010.
As a part of the RILAC2, we designed a low energy beam transport (LEBT) from the ECRIS to the
RFQ entrance (Fig. 2). In this paper, we present therequirements of the LEBT and the challenges faced
in its design, and also our ﬁnal design to overcome
these challenges. The LEBT is now under construction
based on this design. We assumed the beam properties since we had to design the LEBT before testing
the newly developed ECRIS. The main requirementsof the LEBT are summarized in Table 1.
Table 1. The main requirements of RILAC2 LEBT.
Total length (ECRIS to RFQ)
Beam
Acceleration voltage
Estimated emittanceBρ
Energy per nucleon
90◦ analyzing bending magnet
Bending radius
Resolution
RFQ Acceptance
ϵx , ϵyxmax , ymax′
x′max , ymax
r12 , r34

6.8 m
U35+
22.3 kV∼ 150 π mm·mrad
0.056 Tm
3.28 keV
238

510 mm100
150 π mm·mrad
4.47 mm49.0 mrad-0.410

Table 2. Assumptions in the design of RILAC2 LEBT.

The U35+ beam emittance in the region beyond
the analyzing bending magnet was estimated from theresults of experiments performed using the Versatile
ECRIS for Nuclear Science (VENUS) at the Lawrence
Berkeley National Laboratory5) . The design of theanalyzing bending magnet is the same as that of the
VENUS system in which sextupole compensation has
been achieved on its yoke.
The beam condition strongly depends on the degree∗1yoichi.sato@j-parc.jp, yoichisato@riken.jp

of space-charge (SC) compensation. The maximum expected U35+ current would be 0.5 emA. However, since
oxygen is used as a supporting gas at the ECRIS, the
ECRIS produces not only U35+ but also U ions withother charge states and O ions. Therefore, the total
produced ion current may be over 10 emA. The SC effect of the ions increases the beam emittance and inﬂuences the beam properties of U35+ in the low energy region. In order to compensate the SC eﬀect of the ions,
we keep and use the electrons within the LEBT. The
electrons are originally produced due to residual-gas
ionization or beam scratching on beam chamber. We
installed a double-layered extraction system at ECRIS.
This system produces a mirror electric ﬁeld to keep theelectrons within the LEBT. Only magnetic lenses areused as the lens elements in the LEBT so that the electrons within the LEBT are not absorbed. The compensation ratio was estimated to be 80∼99%5)6) . In ourdesign, we consider that the LEBT consists of three
sections described as follows. Section 1 is around theextraction electrode of the ECRIS. Section 2 is fromthe ECRIS to the analyzing bending magnet. Section
3 is downstream of the analyzing bending magnet. The
assumptions adopted in the simulation for each section
are listed in Table 2. We performed cylindrical simulations of multiple-ion beams in section 1 using IGUN.
We compared two diﬀerent simulations in section 2.
One was the simulation of multiple-ion beams using
KOBRA, and the other was the simulation of singleion beams using TRANSPORT. The emittance ﬁguresof U35+ ions in both simulations are similar. However,the KOBRA simulation showed non-normalized emittance of around 600 π mm·mrad, which was four times
larger than the emittance estimated using VENUS. In
section 3, by taking into consideration the RFQ acceptance, we adopt an initial condition based on the results at the end of the section 2 in phase space obtainedusing KOBRA, and an emittance of 200 π mm·mrad.

Section1
2
2

SC ratio
100%
10%
10%

2

0∼100%

30∼100%

Current
Ions
Code
10 emAO, U IGUN7)
0.1∼1 emA O, U KOBRA8)
0.1∼1 emA U35+ TRANSPORT9)
upstream of the analyzing BM
0∼0.5 emA U35+ TRANSPORT
inside the analyzing BM
0∼0.5 emA U35+ TRANSPORT

The transverse real space distribution of ions had
not been clearly understood. Therefore, the simula-- 119 -

tions in section 3 were performed by adopting several
initial conditions with diﬀerent horizontal and vertical
waist positions. The LEBT was designed for as many
diﬀerent beam conditions as possible. We required lenselements having large acceptance and an accurate diagnostics system in the LEBT.
The RFQ is a four-rod RFQ having four vanes whoseplanes are inclined both horizontally and vertically atan angle of 45◦ 10) . It will be operated at a frequency of
36.5 MHz. It requires 22.3 kV for 238 U35+ and cylindrical strong-focus acceptance. We need a minimum
degree of freedom of four for the LEBT lens elements
for good matching. A buncher of 18.25 MHz is required
upstream of the RFQ. The buncher is a two-gap systemhaving 64.5 mm gaps, 150 mm total length, and 40 mm
inner diameter. The buncher should be located within
1 m of the RFQ in order to ensure that the required
voltage is obtained. The beam diameter through thebuncher should be less than 25 mm in order to obtain
the required electric-ﬁeld distribution. These requirements are necessary to ensure a transmission of over
75% through the RFQ11) .
There are two diagnostic systems. The ﬁrst diagnostic system is located downstream of the analyzing
bending magnet. It includes an analyzing slit, a vertical slit, emittance slits, two proﬁle monitors, a viewing
target monitor, a Faraday cup, and a vacuum pump.
Its emittance monitor is expected to have 10% accuracy. The chamber length of the ﬁrst diagnostics system is about 1 m. If we install a quadrupole lens immediately following the chamber, the beam diameter
would be over 100 mm. The second diagnostic system
is located upstream of the RFQ. It has an emittancemonitor, two proﬁle monitors, a viewing target monitor, and a vacuum pump. Its emittance monitor shouldmeasure emittances inclined at 45◦ to operate skewed
quadrupoles between the RFQ and the DTLs. In eachdiagnostic system, the two proﬁle monitors will be used
to adjust the beam axis using steerers.
The ﬁnal RILAC2 LEBT design is shown in Fig.
2. Figure 3 is the U35+ beam proﬁle in LEBT simulated using TRANSPORT. The transverse lens elements are a single solenoid that is placed right after the ECRIS extraction, the 90◦ analyzing bending
magnet, a pair of solenoids, four quadrupoles, and another pair of solenoids. The bending magnet is between
two steerers. The buncher is between two steerers.
The quadrupoles have 100 mm diameter. The pairedsolenoids are identical but will be operated to generatemagnetic ﬁelds in directions opposite to each other12) .
This operation of the paired solenoids prevents the rotation of a solenoid if only one is used. The pairedsolenoids can be used as decoupled isotropic focusing
elements. A diagnostic chamber is present in front ofeach pair of solenoids. The paired solenoids enabled
us to reduce the beam size in the lens elements following the solenoids, to decouple horizontal and vertical- 120 -

emittances, and to ensure that a long drift space exists
before the diagnostic chambers.
References
1) O. Kamigaito et al.: Proc. PASJ6, Tokai, Japan, 2009.
2) Y. Watanabe et al: in this report.
3) Y. Higurashi et al: in this report.
4) K. Suda et al.: in this report; K. Yamada et al.: inthis report.
5) D. Leitner et al.: PAC 05, 179 (2005); D. Todd et al.:ECRIS08, Chicago, USA, 2008.
6) P. Spaedtke et al.: ECRIS08, Chicago, USA, 2008.
7) R. Becker et al.: Rev. Sci. Instrum. 63, 2756 (1992).
8) P. Spaedtke et al.: Rev. Sci. Instrum. 71, 820 (2000).
9) U. Rohrer, (http://pc532.psi.ch/trans.htm).
10) H. Fujisawa, NIM A 345, 23 (1994).
11) H. Okuno et al.: Proc. PASJ6, Tokai, Japan, 2009.
12) Y. Sato, et al.: in this report.

Fig. 1. The layout of the RILAC2.

Fig. 2. The RILAC2 LEBT design. The abbreviations BM,
PS, ST, 4Q, BUN represent the analyzing bending magnet, a set of paired solenoids, a steering magnet, a seriesof four quadrupoles, and a buncher.

Fig. 3. The beam proﬁles in the RILAC2 LEBT simulatedusing TRANSPORT. The abbreviations Sol and Dg
represent a single solenoid and a diagnostics chamber.
The upper half shows vertical beam envelopes and thelower half shows horizontal beam envelopes. The larger
and smaller envelopes are for ions with a current of 1
mA and of 0.1 mA, respectively, in section 2. The ionsin section 3 have a current of 0.5 mA.

RIKEN Accel. Prog. Rep. 43 (2010)

Design of Medium Energy Beam Transport for 127 kV U35+
Y. Sato,∗1 M. Fujimaki, N. Fukunishi, A. Goto, Y. Higurashi, E. Ikezawa, O. Kamigaito, M. Kase, T. Nakagawa,J. Ohnishi, H. Okuno, H. Watanabe, Y. Watanabe, and S. Yokouchi
As a part of the RI beam factory (RIBF) project, wedeveloped a new preinjector line, namely, the medium
energy beam transport (MEBT) line for 127 kV uranium U35+ beams in order to produce intense uraniumion beams. This MEBT line is intended for temporary
operation from 2009 to 2010. It will be dismantled forthe construction of RIKEN’s future linac (RILAC2).
A newly developed superconducting ECR ion source(ECRIS), which was originally developed for RILAC2,
was set on a high-voltage Cockcroft terminal. The
MEBT line extends from the terminal to the entranceof the RIKEN linac (RILAC) (Fig. 1).
U35+ beams were extracted from the ECRIS, whose
voltage was higher than that of the Cockcroft terminal by 15∼17 kV. The beams were transported fromthe terminal to the MEBT line through an acceleration tube. The voltage of the Cockcroft terminal wascontrolled to obtain a beam energy of 127 kV in the
MEBT line. After passing through the 13.6 m long
MEBT line, the 127 kV U35+ beams were directly
injected, without using a radio-frequency quadrupole(RFQ), into the RILAC at RIKEN. In this paper, we
present the design of the MEBT line and the results
obtained using this line.
The MEBT optics are set in the following order: theacceleration tube, triplet quadrupoles (TQ), doublet
quadrupoles (DQ), buncher, DQ, 60◦ bending dipole(BM), 2 DQs, -60◦ BM, and DQ. The MEBT line wasdesigned by performing simulations of the acceleration
tube and the optics downstream of the tube. We had todesign the MEBT before testing the newly developed
ECRIS. Therefore, we needed to assume the beam
properties for low energy beam transport (LEBT)1)
using the Cockcroft terminal. We assumed that the
U35+ beam had upright emittance of 150 π mm·mradand a circular beam spot of 10∼20 mm diameter at
the LEBT slit position that is 0.5 m upstream of theacceleration tube entrance. The beam state greatly
depends on the extent of space-charge compensation.
The MEBT line was designed to operate under as many
diﬀerent beam conditions of the LEBT as possible.
The acceleration tube was originally designed for an
acceleration voltage of 100 kV, but it can be used for
up to a voltage of 120 kV. In fact, the acceleration tube
was operated at 110∼112 kV in 2009. To model theacceleration tube, we used KOBRA simulation code2) .
The diameter of the acceleration tube was chosen so
as to avoid aberration, and the chosen value was 100
mm. The longitudinal distance between the 100 kVelectrode and ground electrode is 260 mm. By per∗1

yoichi.sato@j-parc.jp, yoichisato@riken.jp

forming the simulation, we chose the acceleration tube
geometry such that the beam emittance and the ionspreed ratio were decreased appropriately during acceleration (Figs. 2, 3). In our model, the U35+ beam
induced a space-charge eﬀect of 200 eµA around theacceleration tube.
TRANSPORT code3) was used to design the MEBT
that extended from the acceleration tube exit to the
RILAC entrance. A H-H’ emittance diagram as theinitial conditions for the TRANSPORT simulation waschosen to be similar ﬁgure obtained using the resultsof KOBRA simulation at the accelerator tube exit The
initial conditions corresponded to circular beam spotsof 10 mm, 12 mm, 15mm, and 20 mm diameter at
the slit in the LEBT and emittance value of 65. 6 π
mm·mrad downstream of the acceleration tube (Table
1).
Table 1. Initial conditions of simulations at accelerator
tube exit for diﬀerent beam diameter at LEBT slit.
at LEBT slit
Diameter
10 mm
12 mm
15 mm
20 mm

At acceleration tube exit
xmax
x′max
r12
Emittance = 65.6 π mm·mrad
14.9 mm 5.27 mrad
0.553
13.0 mm 5.46 mrad
0.384
10.9 mm 6.06 mrad 0.0859
9.13 mm 7.55 mrad-0.304The beam-matching conditions at the surface of theconnection ﬂange of the RILAC entrance were basedon the E014 data that was previously obtained at
RIKEN4) : xmax = 7.13 mm, x′max = 14.2 mrad, r12′= -0.761, ymax = 12.5 mm, ymax
= 5.30 mrad, r34 =-0.134, ϵx = ϵy = 65.6 π mm◦mrad.
The MEBT line was designed to be achromatic.
Tbe beam diameter was set to be ¡ 30 mm at thebuncher and ¡ 50 mm for the entire beam line. Further,
the MEBT line was designed to be stable even if thequadrupoles were misaligned or some adjustments that
could aﬀect achromaticity were performed. The resultsof the TRANSPORT simulations show that ∆p/p ≤0.03% has to be achieved at the acceleration tube exit.
This restriction is based on the longitudinal acceptanceof the RILAC and it determines the LEBT speciﬁcations. The MEBT line was aligned to satisfy these
conditions, a variety of initial conditions, and a spacecharge eﬀect of 0∼500 eµA (Figs. 4, 5).
On the basis of this design, the MEBT line wasconstructed, and the line was ready for operation in
July 20095) . The commissioning of the MEBT was
performed from July to September 2009. Beams of136
Xe20+ ions, which have the same mass-to-charge- 121 -

ratio as 238 U35+ ions, were used in this commissioning. 238 U35+ beams were used in the operation of the
MEBT line from November to December 2009. The
currents measured in these operations are listed in Table 2. Here, FC represents a Faraday cup. FCH0 isdownstream of the analyzing bending magnet in the
LEBT, FCe014 is the exit of the MEBT, and FCe11 isdownstream of the analyzing bending magnet right after the RILAC. The MEBT magnets were optimized to
improve the RILAC transmission rather than to maximize the FCe014 current.

3) U. Rohrer:
In Graphic Transport Framework(http://pc532.psi.ch/trans.htm).
4) O. Kamigaito, A. Goto et al.: RIKEN Accel. Prog.
Rep. 30, 191 (1997). M. Tonuma et al.: RIKEN IPCR
51, 53 (1975). A. Goto et al.: Unpublished.
5) Y. Watanabe et al.: in this report.

Table 2. The currents measured at LEBT, MEBT, and RILAC.
Date
2009/9/11
2009/11/13
2009/11/16

Beam
136
Xe20+
238 35+
U
238 35+U

FCH024 eµA
10.3 eµA
10.0 eµA

FCe01417 eµA
8.0 eµA
6.2 eµA

FCe11
8.4 eµA
N/A
2.7 eµA

For 238 U35+ , the value of emittance that includes
only current greater than 1/3 of the peak current in
MEBT may be ϵx ∼= ϵy ∼= 30 ∼ 40 mm·mrad at 127 kV;
this emittance value was estimated from the data obtained using a proﬁle monitor by tuning a quadrupole.

Fig. 3. The H-H’ diagrams of U35+ for the acceleration
tube exit. Emittance at the accelerate tube entrance is
150 π mm◦mrad.

References
1) Y. Sato et al.: RIKEN Accel. Prog. Rep. 42, 148(2009).
2) P. Spaedtke, C. Muhle: Rev. Sci. Instrum. 71, 820(2000).

Fig. 4. The MEBT beam proﬁles of the 127 kV U35+ beams
with zero-current space charge. The upper line is thevertical proﬁle; the lowerd line, the horizontal proﬁle;and the dashed line, R16. The transverse proﬁle is in
cm; the longitudinal, in m; and R16, in cm/percent.

Fig. 1. The MEBT line. The transverse lens elements between the acceleration tube and the RILAC entrance
are two 60◦ bending magnets and 13 quadrupoles.

Fig. 2. Potential distribution in the 100 kV acceleration
tube.

- 122 -

Fig. 5. The MEBT beam proﬁles of the 127 kV U35+ beams
with 500 eµA space charge. The upper line is the vertical proﬁle; the lowerd line, the horizontal proﬁle; andthe dashed line, R16. The transverse proﬁle is in cm;
the longitudinal, in m; and R16, in cm/percent.

RIKEN Accel. Prog. Rep. 43 (2010)









         


       

       
        


          

       
        



      





  
         
          




                     
               

 



- 123 -




        
                  
     

         
      
        
       
          

      



             



      
      

    
      

 
   
     


     
         
      







             
        
              
 
   
        



        






         
         


          
 


- 124 -

 RIKEN Accel. Prog. Rep. 43 (2010)Fabrication of thicker carbon foils with longer lifetime

H. Hasebe, H. Okuno, H. Kuboki, N. Fukunishi, O. Kamigaito A. Goto, M. Kase, and Y. Yano

A carbon foil (C-foil) is commonly used as a charge
stripper in a heavy-ion accelerator such as RIKEN RIBF.
However, the decrease in their lifetime when they are
exposed to high-intensity heavy-ion beams is a serious
disadvantage. Since 19991), we have been developing
C-foils that would have a long life even when exposed tothe high-intensity and high-energy beams of the RIBF. The
RIBF is continuously improved and the beam intensity is
increased day by day. Since 2005, we have been fabricating
polymer-coated carbon foils (PCC-foils) using a magnetron
sputtering source by a polymer-coating technique with theaim of fabricating larger and thicker C-foils.2,3). However,C-foils with adequately high quality and long lifetime havenot been fabricated yet using this method.
	
 
	
 
	
 
	
 
	
 
	
 
	
 
	
 
	
 
	
 
	
 
	
 
	
 
	
 
	
 
	
 
	
 
Fig.1. High-vacuum evaporation system (SH-350 by
ULVAC).

Fig.2. A state of the evaporation.

We installed a high-vacuum evaporation system (SH-350
by ULVAC4)) at the RILAC building in August 2009 (Fig.
1). The system has a vacuum chamber with a diameter of
500 mm and a height of 300 mm. It also has a oil-sealed
pump and a 1800 L/s turbomolecular pump. A magnetron
sputtering source is installed in the upper part of theevaporation chamber. The target of the magnetron
sputtering source is a graphite plate with 6 inches diameter.
A substrate is placed in the lower part of the evaporationchamber and is rotated during evaporation to ensure that thefilm thickness remains uniform. The substrate is 5 inches indiameter. A silicon wafer or glass material is used as thesubstrate. The substrate can be heated up to 250 ˚C. The
distance between the substrate and a magnetron sputtering
source can be adjusted from 35 mm to 85 mm. Figure 2
shows a photograph taken during the evaporation. The
plasma is produced by the input of DC or RF (radio
frequency) power into the evaporation chamber. Argon gas
is circulated in the chamber and the flow rate of the gas isregulated using a mass flow meter. A vacuum of about 0.6
kPa exists during the evaporation. The relationship between
thickness of carbon evaporated in one hour and the DC
power of the magnetron sputtering source is shown in Fig. 3.
The thickness of the C-foil was determined by dividing themeasured mass of the C-foil (g) by the area (cm2). The
deviation in the C-foil thickness was within 10%. The glass
substrate on which the evaporated carbon was deposited
looked like a mirror surface, as shown in Fig. 4. The C-foilremoved from the substrate also appeared like a mirror.
	
 
	
 
	
 
	
 
	
 
	
 
	
 
	
 
	
 
	
 
	
 
	
 
	
 
	
 
Fig.3. Thickness of carbon evaporated in one hour as afunction of the DC power of the magnetron sputtering
source.

- 125 -

was irradiated by a beam with low intensity. The C-foil was
irradiated with strobe light6) to remove mechanical stress on
the foil and to produce a wrinkle on the foil. After that, we
did not observe the immediate cracking of the C-foils andthey were used for about 5~9 hours. A beam irradiation test
using a C-foil with a large area attached on a rotating
cylindrical stripper device7) will be performed in the near
future.
References

Fig.4. The glass substrate on which evaporated carbon
was deposited.

1) H. Hasebe, M. Kase, H. Ryuto, and Y. Yano: Proc. The 17th
International Conference on Cyclotrons and their Applications(Cyclotrons 2004), Tokyo, Japan, October 2004, p. 313.
2) H. Hasebe, H. Ryuto, N. Fukunishi, A. Goto, M. Kase, and Y.
Yano: Nucl. Instr. and Meth. A 590, 13 (2008).
3) H. Hasebe, H. Okuno, H. Kuboki, N. Fukunishi, O. Kamigaito,
A. Goto, M. Kase, and Y. Yano: RIKEN Accel. Prog. Rep. 42,
133 (2009).
4) ULVAC, Inc.	
 URL: <http://www.ulvac.co.jp/>
5) Nanosurf AG, URL: <http://www.nanosurf.com/>
6) H. Hasebe, M. Kase, E. Ikezawa, Y. Miyazawa, M. Hemmi, T.
Aihara, T. Ohki, and H. Yamauchi: Proc. The 24th Linear
Accelerator Meeting in Japan, Sapporo, Japan, July 1999, p.
287.
7) H. Ryuto, H. Hasebe, N. Fukunishi, S. Yokouchi, A. Goto, M.
Kase, and Y. Yano: Nucl. Instr. and Meth. A 569, 697 (2006).

(a)(b)
Fig.5. (a) is the C-foil surface on the side of the substrate,and (b) is C-foil surface on the side of the magnetron
sputtering source (AFM images).
Figure 5 shows the images of the C-foil surfaces obtainedusing an atomic force microscope (AFM5)). The surface
area shown in the image is 5 µm x 5 µm. Figure 5 (a) shows
the surface on the side of the substrate, while Fig. 5 (b)shows that on the side of the magnetron sputtering source.
As seen in Fig. 5 (a), the surface is almost smooth. The
other surface is slightly rough, as shown in Fig. 5 (b).
However, the deviation in the thickness is about several
nanometers, which is considerably lesser than that in case of
PCC-foils or commercially available C-foils. We succeededin fabricating C-foils with thickness from 0.2 to 1.5 mg/cm2
by this method. Previously, 0.5 mg/cm2 was the maximum
thickness obtained. Carbon foils with a thickness of 0.3
mg/cm2 were attached to a fixed holder having a hole ofsize 14 mm x 23 mm and were used as a practical charge
stripper during the beam time in December 2009. The
carbon foils were irradiated with a 11-MeV/u 238U35+ beam
having an intensity of about 2~3 eµA which was obtained
from the RIKEN ring cyclotron (RRC). The beam spot size
was approximately 5 mm in diameter. At first, the C-foil
broke immediately within a short time even when the foil

- 126 -

 RIKEN Accel. Prog. Rep. 43 (2010)


Renovation of the central region of RIKEN AVF cyclotron andresults of beam acceleration test
A. Goto, S. B. Vorozhtsov,1 E. E. Perepelkin,1 A. S. Vorozhtsov,1 S. Watanabe,2 S. Kubono,2 and M. Kase

In order to increase the maximum available energies of
O7+ and 6Li3+ ion beams to 12 MeV/nucleon (see Fig. 1),
we renovated the central region of the AVF cyclotron in
August 2009 on the basis of beam simulations. We thenperformed an acceleration test in September 2009 by using
the 4He2+ ion beam, which is equivalent to a 6Li3+ ion beam,with the new central region geometry.
Fig. 1 shows the performance of the AVF cyclotron. The
shaded pentagon-shaped region indicates the region where
ion beams are designed to be available. The inclined line
16

Fig. 1. Acceleration performance of the AVF cyclotron. See
the text for details.

shows the limit determined for the original design on thebasis of the central region geometry (see Fig. 2) and thefrequency characteristics of the available dee voltage. If thebeam is allowed to pass through (not necessarily along thecenter of) the aperture of the channel at the inner tip of thefirst dee electrode, Dee1, the maximum beam energy may
increase to some extent even with this geometry. In addition,
beam simulations performed using the 3D electricfields1,2,3,4) calculated for the central region revealed that theoriginal design underestimated the limit. Actually, a 11
MeV/nucleon 16O7+ ion beam and a 11.2 MeV/nucleon 6Li3+
ion beam were accelerated successfully in December 2008.
To further increase the beam energies, however, thegeometry of the central region had to be modified.
The renovation process involved the following steps: 1)
replacement of the RF shield accommodating the spiralinflector as well as the inner tips of Dee1 and Dee2 withnew ones (see Fig. 3) and 2) elongation of the inflector
electrode by attaching 2-mm-thick copper plates to the end
surfaces of the inflector entrance and exit (see Fig. 4). The
aim of the first step was to bring the side walls of thedee-electrodes and the wall of the RF shield as close to thecyclotron center as possible, as shown by the white curves
in Fig. 3. 3D beam simulations performed with the newgeometry confirmed that the beam energy can be increased
to 12 MeV/nucleon while ensuring the beam quality is as
good as that with the old geometry. The second step wasnecessary since previous 3D beam simulations showed that
reduction of the inflector-electrode length by cutting off a
4-mm (half of the electrode gap) pieces from each end
contributed to overcorrection.

Spiral inflector
Dee1

Main probe
Dee2
Phase slit

Fig. 2. Original geometry of the central region of the AVF
cyclotron.
1
2

Joint Institute for Nuclear Research, Russia
Center for Nuclear Study, University of Tokyo

Fig. 3. Renovation of the central region. White line: oldgeometry; shaded part: new geometry.

- 127 -

Fig. 4. Renovation of the spiral inflector. The inflector
electrode was elongated by attaching 2-mm-thick copper
plates to the end surfaces of the inflector entrance and exit.
In the beam test performed in September 2009, we
focused on the injection, acceleration, and extraction of a11.2 MeV/nucleon 4He2+ ion beam. The acceleration to 12
MeV/nucleon, which had been previously planned, had tobe canceled owing to machine trouble. Fig. 5 shows thebeam transmission through the AVF cyclotron along withthat observed in December 2008. The injection efficiency(the ratio of the beam intensity at I36 and R = 74 mm) for
the new geometry was approximately 50 %, which was fivetimes that obtained for the old geometry. This highefficiency was obtained when the Dee1 voltage was 37 kV,
which was lower than that applied in the previous test
(41 kV). The extraction efficiency, on the other hand, wasvery poor, because of which there was no notable
improvement in the total transmission efficiency(approximately 10 %). From the performance achieved thus
far, we speculated that the operational parameters for the
extraction system, including those for the harmonic coils,
were not optimal. The performance can be improved withcareful tuning of the aforementioned parameters for future
extractions.
The 3D beam simulation results show that the deevoltage required for the 12 MeV/nucleon 16O7+ ion beam isFig. 5. Comparison of beam currents (relative values)
obtained with the old and new central-region geometries.
I36 and C01 denote Faraday cups placed immediately
before and after the AVF cyclotron, respectively. The
numbers with mm units denote the radial positions of themain probe: 825 mm denotes the position after the
extraction system. The beam current is staggered at 500
mm-700 mm because the main probe fails to detect theentire beam current when the beam is not aligned
appropriately with the probe; this is because of off-centered
beam oscillations.
49 kV, which is close to the presently available maximum
voltage. Furthermore, it has been found in the present test
that the experimentally optimized dee voltage for Dee1 isslightly lower than the required voltage determined by the
3D beam simulation. Therefore, it can be concluded that
acceleration of the 12 MeV/nucleon 16O7+ ion beam (as wellas the 6Li3+ ion beam) is possible with the new central
region geometry.
References
1) A. S. Vorozhtsov et al.: RIKEN-NC-AC-2.
2) E. E. Perepelkin et al.: Proc. RuPAC 2008, p.40.
3) S. B. Vorozhtsov et al.: Proc. RuPAC 2008, p.51.
4) S. B. Vorozhtsov et al.: Proc. 6th Annual Meeting ofParticle Accelerator Society of Japan, Tokai, Japan,
August 5-7, 2009, p.240.

- 128 -

RIKEN Accel. Prog. Rep. 43 (2010)

Possibility of formation of round beams in RIBF cyclotrons
H. Okuno, A. Adelman,∗1 and J.J. Yang∗2[Cyclotron, Space charge]
The increase in the intensity of uranium beam in
the RIBF accelerator complex motivated us to study
the vortex motions in cyclotrons. Longitudinal spacecharge force causes an increase in the acceleration ofhead particles and deceleration of tail particles. The
accelerated or decelerated particles move to higher orlower radii because of the isochronous condition in cyclotron, which causes a rotation of the ion bunch. The
nonlinearity of the space-charge force leads to a spiralshaped halo of the bunch, which finally turns into a rotating sphere. These vortex-motion phenomena weretheoretically studied as shown in the reference1) andexperimentally verified at the PSI Injector II.
In his thesis2) , Pozdeyev described that the effects ofthe space-charge force on the bunches of similar lengths
approximately scale asqI,
γ 5 mhω 3(1)where I is the total beam current, h is the harmonic
number, and the momentum is mγRω. Table 1 lists
the values of the parameter described above in the caseof Injector II, RRC, fRC, IRC, and SRC, indicatingthat the effects of the space-charge force observed in
RRC is approximately same as that observed in the Injector II, while the effects observed in the other three
cyclotrons are small. Therefore, our beam dynamics
study focused on the RRC, which is a low-energy cyclotron.
OPAL-cycl3) is one of the flavours of the Object Oriented Parallel Accelerator Library (OPAL) framework.
It is a new 3D PIC-based self-consistent numerical simulation code that takes into account neighboring bunch
effects. The self-consistency of the code is clarified inelectrostatic approximation. A more detailed description of the OPAL framework and OPAL-cycl code canbe found in the User’s Reference Guide4) .
The RRC consists of four sector magnets and two
double-gap rf resonators. Simulations performed using
OPAL-cycl require an accurate isochronous field map
and radial distribution of rf voltage at the gaps. A
highly accurate field map of the isochronous field was
calculated using ANSYS5) . Radial distribution of rf
voltage was assumed to be constant since radial distribution of the resonator of the RRC remains constantat 18.25 MHz.
Single-particle tracking using OPAL-cycl is necessary to check the isochronism of the field map, the validity of the initial condition, and the matching phase∗1∗2Fig. 1. Top view of single-particle tracking of the reference
particle up to the final turn in RRC.

ellipse before multi-particle tracking including spacecharge forces. Figure 1 shows the single-particle tracking of a reference particle accelerated up to its final
turn. It took about 296 turns for the particle to attaina final energy of the cyclotron.
The phase slip at
the rf-gap crossing, which is shown in Fig. 2, indicating that the used field map is sufficiently isochronous.
Single-particle tracking was carried out with initial offsets of r (z) = 5.0 mm and pr (pz) = 0.0 mrad fromthe static equilibrium orbit at injection energy in order to obtain eigen ellipses in the radial and verticaldirections. The results (Fig. 3) show that the ratiosof the semi-major axis to semi-minor axis are 5.0/4.2
and 5.0/2.5 mm/mrad in the radial and vertical directions, respectively. These ellipses were used as theinitial conditions for multi-particle tracking.
Multi-particle tracking taking into account spacecharge forces was carried out at a beam current of
0.5 mA using the initial conditions obtained from theTable 1. List the value of the parameter of (1) in the text.

Paul Sherrer InstituteCIAE and Tsinghua University- 129 -

PSI
Inj. II
1

RRC

fRC

IRC

SRC

0.644

0.096

0.031

0.016

radial [m]

1000

0.06

10
5

800

0.04

0.02

Turn 0

0
-5

500

0.06

0.04

1
52
103
154
205
256
307
358
409
460
511
562
613
664
715
766
817
868
919
970
1021
1072
1123

400

0.02
Entries

0600

Entries300100000

1000000Mean x -5.409e-13

Mean x -8.182e-14

Mean y 1.824e-07

-0.02

400

RMS x
RMS y

-0.04

Mean y 1.824e-07

0.003476

RMS x 200
0.006951

0.001305

RMS y

200

-0.06

-0.02
-0.04

0.001305

100

-0.06
0

0

-0.06-0.04-0.02 0 0.02 0.04 0.06

-10

-0.06-0.04-0.02 0 0.02 0.04 0.06

longitudinal [m]longitudinal [m]

800

0.06

-20

radial [m]-15radial [m]Phase @gapcrossing (deg.)

4 degreeradial [m]2 degree

15

0.06

700

0.04

600

450
400

0.04

350

0.02

Turn 2

Fig. 2. The blue lines show phase slip at the gap crossing
in RRC while the red line shows 0 ◦ at gap crossing.
The horizontal axis shows the total number of the gap
crossing.

Entries

0
-0.02

RMS x

RMS y 150
0.002259

-0.02
-0.04

㪏㪉㪍

㪄㪍

㪄㪋

㪄㪉

0

-0.06-0.04-0.02 0 0.02 0.04 0.06

radial [m]longitudinal [m]radial [m]

700

0.06

600

0.06

600

0.04

500

0.04

500

0.02

Turn 4400

0.02
Entries400100000

0
-0.02

Entries

Mean x -4.014e-10
Mean y5.96e-08
300

RMS x

0.003009

RMS y

0.002774
200

0Mean y 2.889e-07
RMS x
RMS y

-0.06
0

0

-0.06-0.04-0.02 0 0.02 0.04 0.06
longitudinal [m]

0.06

700

0.04

600

radial [m]radial [m]longitudinal [m]

500

0.02
Entries

0.06

600

0.04

500

0.02

400

100000

Entries

400

0Mean x 1.765e-10

RMS x

300

Mean y 9.247e-08

300

0.003194

-0.02

RMS y

0.002881

200

-0.04

RMS x

0.006269

RMS y

200
0.004097

-0.04
100

100

-0.06

-0.06
0

0

-0.06-0.04-0.02 0 0.02 0.04 0.06

-0.06-0.04-0.02 0 0.02 0.04 0.06

longitudinal [m]longitudinal [m]radial [m]radial [m]

700

0.06

600

0.04

500

0.02
Entries400100000

00.02
Entries

Mean x 3.589e-09

0

Mean y300-1.791e-07

-0.02

600

0.04

500

Turn 8

RMS x

-0.02

100

-0.06

RMS x

100

-0.06

0

0

-0.06-0.04-0.02 0 0.02 0.04 0.06

longitudinal [m]

700

600

0.06

600

500

0.04

500

0.02
Entries

400100000

0.02

Mean y 1.471e-06

300

RMS x

0.00326

longitudinal [m]100000Mean x -2.335e-07

300

Mean y -1.401e-06

-0.02

100

-0.04

0

-0.06

-0.06
-0.06-0.04-0.02 0 0.02 0.04 0.06

00.003066200

400
Entries

Mean x -2.241e-07

RMS y- 130 -

radial [m]longitudinal [m]-0.04

Fig. 3. Eigen ellipses at the first turn of RRC in the radial
and vertical directions.

0.006105

RMS y 200
0.004421-0.04-0.06-0.04-0.02 0 0.02 0.04 0.06

z (mm)

1000003.81e-09

Mean y300-2.695e-07

RMS y 200
0.003142

0400

Mean x0.003097-0.04

㪍

100000Mean x 5.368e-10

Mean y 3.876e-07-0.02

0.003456

100

100-0.06-0.04-0.02 0 0.02 0.04 0.06

00.0066

200

-0.04

-0.06

Turn 6

100000Mean x300
1.829e-10

-0.02

-0.04

-0.02

㪋

50

-0.06
longitudinal [m]Turn 10㪉

0.006998

100

0-0.06-0.04-0.02 0 0.02 0.04 0.06

radial [m]r (mm)

㪏㪉㪋pz (mm)pr (mm)0.002529

200

0.04

㪏㪉㪉

200

RMS y

0.06

㪏㪉㪇

Mean y -2.479e-07

RMS x 300
0.002833

0.06

㪏㪈㪏

100000Mean x250-3.073e-1001001) S. Adam: IEEE Trans. On Nuclear Science 32, 2507
(1985).
2) E. Pozdeyev: Ph. D. Thesis, MSU, USA (2003).
3) J. Yang, A. Adelmann, M. Humbel, et. al.: Proc. of
HB2008, in press, August 2008, Nashville.
4) A. Adelmann, et. al.: Tech. Rep. PSI-PR-09-05, Paul
Sherrer Institut (2009).
5) L. Stingelin: private communication

㪏㪈㪍Entries

Mean y 3.562e-07-0.06

References

5
4
3
2
1
0
-1 㪇
-2
-3
-4
-5

300

100000Mean x400
6.482e-10-0.04

single-particle tracking studies. We performed simulations of the acceleration in the first 10 turns after
injection because we are mainly interested in the behaviour of the bunches just after beam injection. Initial transverse rms emittance was assumed to be 2.5
π mm mrad on the basis of operational experience.
The initial rms bunch length was assumed to be 2 ◦or 4 ◦ in order to study how the bunch length impacts
on the vortex motions. Figure 4 shows the results ofthe simulations. The results for both 2.0 ◦ and 4.0 ◦clearly indicate vortex motions of bunches toward stationary circular distributions. The bunch in the caseof 2.0 ◦ has smaller tails and rotates faster than that in
the case of 4.0 ◦ . More detailed simulations up to thefinal turns taking into account the space-charge effects
from neighbouring turns are in progress.

10
8
6
4
2
0
-2㪏㪈㪋
-4
-6
-8
-10

0.02

500

RMS x

0.005968

RMS y

200
0.004154

100

0-0.06-0.04-0.02 0 0.02 0.04 0.06
longitudinal [m]Fig. 4. Results of multi-particle tracking. The turn numbers are given on the left of the contour plots. The rms
value of the initial bunch length is mentioned at the topof the contours.

RIKEN Accel. Prog. Rep. 43 (2010)

Measurement of Magnetic Field of fRC Sector Magnets
K. Kumagai and N. Fukunishi
The fixed frequency ring cyclotron (fRC) accelerates
uranium beams with a charge state of 71+ 1,2). These U71+
ions are converted from U35+ at the charge stripper locateddownstream of RIKEN Ring Cyclotron (RRC). The
thickness of the carbon film used in the charge stripper isabout 300 µg/cm2. On the basis of the result of themeasurements, the energy spread of the uranium beampassing through the film is estimated to increase by 0.4 0.5 and this increase causes the beam losses. Since theenergy spread is proportional to the film thickness, the useof a thinner film is desirable but it decreases the charge
state of the product with maximum yield. When we use afilm with a thickness of 200 µg/cm2, the maximum yield isin U69+. Therefore it was necessary to perform themeasurement of the magnetic field of the fRC to confirm
whether or not the U69+ ions can be accelerated. We
developed a magnetic-field measuring system capable ofmeasuring the one-dimensional magnetic field along thecenterline of sector magnets.
The fRC consists of four sector magnets, namely, NE,
SE, NW, and SW, whose pole gaps are 50 mm, ten trim
coils are attached to the upper and lower pole surfaces. The
maximum current of the main coil is 650 A, and the
maximum magnetic field at the magnet center is about 1.75
T.
Figure 1 shows a field measuring system. Square pipes,
which are 4-m long, are installed in the beam chamber frombackside of the magnet yoke along the centerlines of thesector magnet. The measurement devices are placed within
the pipes that are at atmospheric pressure. Two measuringapparatus with the same specifications were assembled.
First, two sector magnets on the east side were measured,and then, the two on the west side were measured. The
beam chamber was evacuated during the measurements.

Fig. 2. Block diagram of the measurement and control
system.
!"&

!"%#

!"%

!"$#

*+
,+
*,./0120/3456

!"$

!"##
#''

#('

#)'

#$'

#&'

$''

$('

$)'

$$'

Fig. 3. Excitation curves of the four sector magnets
observed at R = 2600 mm and calculated strength by
TOSCA-3D.

Fig. 1. Photograph of the magnetic field measuring system.
The left of figure is a backside of the magnet yoke.

Figure 2 shows a block diagram of the measurement
system. Most of the driving devices such as stepping motors,
linear encoders and limit switches were recycled from themagnetic-field measuring equipments of the SRC. NMR
measuring instrument (Echo Electric Co., Ltd, EFS-800S)
and high linearity Hall-effect sensorsF.W. BELL Products;
BHT-900 serieswere used as measuring probes. The fields
were measured using both the NMR and Hall sensors in theregion where the magnetic field was uniform and by Hallsensors in the region where the magnetic gradient wasstrong. The Hall sensors were fixed on a block where thetemperature was controlled to within 30  0.2  foraccurate measurement. As several years had passed since- 131 -

the Hall sensors had been calibrated, they were recalibrated
with the NMR measured in the uniform field area. The
variation in the measurements of the Hall sensors between
several years ago and the current were about 10 gauss. A
program for the field measurement was written in Python
using VISA (Virtual Instrument Software Architecture). The
magnet power supplies were controlled using EPICS.
!"#(

7895:;/2<=/:>?<@AB

!"#'
!"#&
!"#%
!"#$

*+
,+
*,,-./0123415160

!"#!
!"#
!'))

$)))

$'))

%)))

%'))

CDEEB

Fig. 4. Difference in the magnetic field distributions offour sector magnets at a main coil current of 650 A
and a calculated isochronous field distribution for
U69+ acceleration.
"#""'of 2600 mm on the sector centerlines are shown in Fig. 3.
The calculation results by TOSCA-3D at 636 A and 642 A
are also shown. The measured results are in good agreementwith the calculated values.
Figure 4 shows the magnetic field distributions along
the centerline of the four sector magnets at a main coilcurrent of 650 A. The field distributions of the NE sector
and the SW sector are about 30 gauss smaller than those of
NW and SE sectors. These discrepancies can be correctedby 30-A bypass power supplies of the main coils and ±200
A trim-coil power supplies which exist individually by eachsector. The calculated isochronous magnetic field
distribution for U69+ acceleration is also shown in Fig. 4.
Since the measured distributions were significantly larger
than the calculated distribution, we can conclude that it ispossible to obtain the isochronous field distribution that isrequired for U69+ acceleration.
An example of the magnetic field distribution producedby trim coils is shown in Fig. 5. The current of each of themain coils and the trim coils to generate the isochronous
magnetic field can be determined by precisely fitting thesemeasurement results.
Furthermore, in order to accelerate U69+ beam we need toincrease the maximum currents of injection and extraction
magnet power supplies (EBM, MIC2, MDC1). After the
improvement for magnet power supplies, we will beplanning to accelerate U69+ beam.
References
1) N. Fukunishi et al.: RIKEN Accel. Prog. Rep. 41, 79, 81 (2008).
2) N. Fukunishi et al.: RIKEN Accel. Prog. Rep. 42, 105 (2009).

"#""$

)*+,-

"#""%
"#""&
"
1

!"#""&!"#""%!"#""$
&(""

%"""

%(""

$"""

$(""

.+//0

Fig. 5. Trim-coil field distributions at a main-coil currentof 650 A. The currents are +100 A for each trim coil.
A indicates the distribution after the ten trim coils
are excited one by one and then returned to theirinitial states.
The magnetic fields were measured at main-coil current
between 500 and 650 A; the current was raised by 15 A for
consecutive measurement. On the other hand, the trim coilcurrents were increased by 50 A for consecutive
measurements. The interval between measurement was 20mm for main coil and was 10 mm for trim coil. The magnet
was initialized before each measurement of the main-coilfield.
Excitation curves of the four sector magnets at a radius- 132 -

RIKEN Accel. Prog. Rep. 43 (2010).

������������ �� ������ ������ ��� ����� ��������
A. Uchiyama,*1 M. Kobayashi-Komiyama, M. Fujimaki, Y. Higurashi, M. Tamura,*1 and T. Nakagawa

To increase the intensity of the Uranium ion beam used in
the RIKEN RI beam factory project, a new RIKEN 28GHz
superconducting ECR ion source (28GHz-ECRIS) wasconstructed in 2009.1) For effective and stable operation of
the 28GHz-ECRIS, the client system should have auser-friendly user interface (UI) in the control system. For
this reason, we constructed a new client system with agraphical user interface (GUI), a web interface and a dataacquisition system (DAQ). In this paper, we report thesystem and its status in detail.
To control the 28GHz-ECRIS, the system incorporated
with several types of distributed systems for remote control
along with Ethernet. For the control of main devices such as
gas valves and the rod position in 28GHz-ECRIS, a
combination of a Yokogawa F3RP61-2L module that acts an
EPICS input/output controller (IOC) and FA-M3
programmable logic controllers (PLCs) is adopted with theembedded EPICS technology.2,3) A vacuum control system
and a beam diagnostic system are constructed by EPICS
using Linux-based IOCs connected with N-DIMs via
Ethernet. The bending magnet control system and steering
magnet control system comprise a VME-based IOC that
communicates with NIOs.3) To facilitate informationexchange among different types of controllers, the protocol
for the abovementioned controllers should be unified by achannel access (CA) protocol from the client's point of view.
The 28GHz-ECRIS control system, however, includes not
only an EPICS-based system but also a standalone systemthat uses Melsec PLCs for controlling superconducting
magnet. The client system for the Melsec PLCs has been
constructed by using SoftGOT1000, and it can be run on a
Microsoft Windows XP PC. Therefore, our main work is toconstruct the client system for 28GHz-ECRIS operation
with exception of the superconducting magnet. The
requirements for the client system are as follows:z Useful GUI application for main controlz XY plotter
z Beam current monitor
z Log notebook
z Water leak alertz Data acquisition system
For the 28GHz-ECRIS client system, two Microsoft
Windows XP PCs are used in the RILAC control room (seeFig. 1). The X Window System with Cygwin is installed on
the PCs; the system has six displays based on
multiple-display environment. A main GUI panel forcontrolling the gas valves, RF power supplies, magnets
power supplies, and beam extraction devices has beendeveloped by using EDM. EDM is one of the motif-based
display managers provided by the EPICS collaboration fordeveloping a client system with a GUI. Before constructionof 28GHz-ECRIS client system, the many GUI applications
in RIKEN RIBF control system were developed by using
MEDM. Since EDM has following advantages over MEDM,
we adopted the former for development of GUI applicationsin 28GHz-ECRIS client.
1) The EDM has rich component for GUI objects. For
example, the mouse-operated up-down button in EDM issuitable for the operations of the magnet power supply
because separate functions can be allocated by right click
and left click.
2) In the X window system, it is available to set the windowat the required position. EDM has a high degree of usability
in multiple displays with wide area.
3) It is possible to output the calculated values to the GUI
application without the need for maintaining any calculation
records into the EPICS database. Therefore, it is possible tosimplify source code and reduce the number of programs.
As an example, a constructed XY plotter chart is shown in
Figure 2.

Figure 1. Client PCs with Microsoft Windows XP in
RILAC control room.

Figure 2. XY plotter chart developed by using EDM in*1

SHI Accelerator Service Ltd.

- 133 -

28GHz-ECRIS operation

For monitoring the 28GHz-ECRIS beam current, a GUI
application is developed by using EDM. On the other hand,the beam current for another ion source, RIKEN
18GHz-ECRIS, was regularly monitored by the operatorswith the help of a picoammeter for beam tuning.
Comparison of both methods reveraled the picoammeter
was more suitable for beam tuning. Therefore, in the future,
we plan to develop a new GUI meter that is ergonomically
better than the picoammeter for beam current monitoring.
Since there are numerous parameters related to the
28GHz-ECRIS operation, maintaining records in a paper
notebook is not feasible. To save the 28GHz-ECRIS
parameters in an effective manner, we plan to construct apaperless log system by using Wiki (See Fig. 3). Wiki is asystem that can edit and create hypertext documents on the
web server by using the web browser; HTML knowledge is
not required in this case. Currently, various types of Wikiare being used because of the increase in the rate of Internet
access around the world. In our system, an open-source
PukiWiki4) is installed in the server. Simultaneously, we
have developed a program for the client; this program
dumps image files from the GUI clients and automaticallypastes the image file inset the PukiWiki page. The
procedure for saving the 28GHz-ECRIS parameters is asfollows.
1. Click the icon on the GUI to dump the image file.
2. Edit the Wiki page that has the image file, if needed.

inputted comments. Therefore, it is easy to find a parameterlog from a large number of the page. Thus, we confirmedthat this Wiki-based system is more useful for recording theparameters than is a paper log notebook.
In the case of a water leak, the accelerator operators arealerted by the hardware buzzer. In our system, water leak inthe 28GHz-ECRIS room is triggered by an alarm system byusing the EPICS sequencer on F3RP61-2L. As a client forembedded EPICS on F3RP61-2L, a hardware alarm that use
a PIC network interface card (PICNIC) is implemented in
the control room.5) On the other hand, the EPICS
collaboration provides Alarm Handler as a standard
software for the same purpose. However, for Alarm Handler
to provide the desired service, the operating application and
X Window System must be continuously run on the PC
equipped with speakers. For this reason, the real emergency
alarm function should be active at all times with the
hardware alarm.
By MyDAQ26) developed at JASRI/Spring-8 as the DAQ
in the 28GHz-ECRIS, we record EPICS values such as
vacuum, extraction current, and RF power in the MySQL
database. In our system, we developed an EPICS CA client
for data collection. Data are added to the MySQL database
every 10 second via a socket connection to the server thatruns MyDAQ2. Since the graph and text can be easily
displayed on web browsers, the web applications have auser-friendly UI as well as a Wiki-based system. The DAQ
based on MyDAQ2 can be used for reducing the turnaroundtime during system construction.
One of the authors (A. U) wishes to thank Ms. T. Hirono,
JASRI/Spring-8, for assistance in the construction of the
MyDAQ2 system.
References

1) Y. Higurashi et al.: in this report.
2) J. Odagiri et al.: Proc. ICALEPCS09, Kobe, Japan, 2009.
3) M. Komiyama et al.: Proc. ICALEPCS09, Kobe, Japan, 2009.
4) http://pukiwiki.sourceforge.jp/
5) A. Uchiyama et al.: Proc. ICALEPCS09, Kobe, Japan, 2009.
6) T. Hirono et al.: Proc. PCaPAC08, Ljubljana, Slovenia, 2008,
p.55.

Figure 3. Wiki page with an image dump file for
28GHz-ECRIS main control GUI panel
In the main panel, vacuum monitor and XY plotter chart
provide the above-mentioned function in cooperation with
Wiki. In this manner, operators can record the parameters
easily quickly and accurately many times during anexperiment. In the actual 28GHz-ECRIS operation,
operators obtain the parameter log every 3h. The Wiki pageoften contains important information when an operator
informs others of the trouble status. In addition, thisWiki-based system has a log management function thatcarries out a search by the keyword method forautomatically inserted EPICS record values and manually- 134 -

RIKEN Accel. Prog. Rep. 43 (2010)

Improvement of beam energy and longitudinal beam proﬁlemeasurement system
T. Watanabe, N. Fukunishi, K. Yamada, M. Kase, M. Wakasugi, M. Fujimaki, N. Sakamoto, K. Suda, H.
Kuboki, R. Koyama, and O. Kamigaito
Plastic scintillation monitors (scintillation monitors)
have been fabricated to evaluate the energy and longitudinal proﬁles of heavy-ion beams at the RIKEN
RI beam factory (RIBF)1,2) . Four sets of scintillation
monitors (8 monitors) were installed in the transportlines of the RIKEN heavy-ion linac (RILAC), RIKEN
ring cyclotron (RRC), ﬁxed-frequency ring cyclotron(fRC), and intermediate-stage ring cyclotron (IRC) tomeasure the time of ﬂight (TOF), namely the acceleration energy, of the heavy-ion beams. Furthermore, atotal of six scintillation monitors were installed in thetransport line, upstream of the injection points anddownstream of the extraction points of these accelerators, to optimize the phase between the RF cavities
and the beam. The improvements made to the scintillation monitor system are reported in this article.
Figure 1 shows a block diagram of the system.
The plastic scintillator is pneumatically inserted into
the beam transport chamber by the pneumatic rotary
feeder when the measurement process is started. Whena scintillation material is bombarded by a charged particle, ﬂuorescence photons are produced. Then, thesephotons are ampliﬁed by a photomultiplier that has
extremely high sensitivity. Longitudinal beam proﬁles
are obtained using a time-to-digital converter (TDC),
which digitizes the time lag between the start pulse(detected signal) and the stop pulse (bunch clock).
The energy of the beam can be calculated from themeasured TOF of the beam by using a longitudinal
proﬁle monitor set. For data acquisition and control.τVQH
2NCUVKEUEKPVKNNCVQT

$GCO

2/6

2/6

2#

2#

%(&

%(&

%(&

(#

(#

4(

5612

56#46

6&%

2%
.KPWZ 8KPG% 2#9*8%TCVG%QPVTQNNGTEE
%#/#%2%+

2/6 2JQVQOWNVKRNKGTVWDG
2# 2TGCORNKHKGT%(& %QPUVCPVHTCEVKQPFKUETKOKPCVQT(#(CPQWV
6&% 6KOGVQFKIKVCNEQPXGTUKQP*8 *KIJXQNVCIGRQYGTUWRRN[

9KPFQYU :2.CD8+'9/CE
4GOQVGEQPPGEVKQP

0GY'VJGTPGV
6%2+2%QPVTQNTQQO

Scintillatordet gui
Ligh side)
(in

Slit

Photo
multiplier

Slit(Beam)
Light guideFig. 2. Photo of scintillation monitor with slit and lightguide.

of the scintillation monitors, the CAMAC system withLinux-based PCs is used. These PCs are connected toa laptop in the main control room located 200 m fromthe RRC hall by using Ethernet and remote connection. The measured results are displayed by PAW++
based on several components of the CERN Program
Library. The driving control and status monitoring of
the plastic scintillator are controlled by the EPICS system. These programs are written in C language using
PAW++ macros and are run on the Linux (Vine 4.0)
operation system. This year, to help users operate thesystem more easily, a new embedded controller witha higher-performance CPU has been introduced andnew programs have been written in LabVIEW3) , these
programs run on the Windows 7 operation system.
A device driver for the TDC (TOYO CC/7700) andLabVIEW’s call library function nodes using dynamic
link libraries (DLLs) have been newly developed. Currently, programs for driving control, data acquisition,and result display have been developed, and work on
integrating these programs is in progress.
In order to improve the time resolution, a slit and alight guide have been newly fabricated. Figure 2 shows
the scintillation monitor with the slit and light guide.
Since the unnecessary light is cut oﬀ, the resolutionof the TOF is enhanced, namely, the resolution of thebeam energy is improved.
References

Fig. 1. Block diagram of beam energy and longitudinalbeam proﬁle measurement system.

1) T. Watanabe et al.: RIKEN Accel. Rep. 39, 241 (2006).
2) T. Watanabe et al.: RIKEN Accel. Rep. 40, 131 (2007).
3) National Instruments Co., Ltd.

- 135 -

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Consistency in measurement of beam phase and beam intensity
using lock-in ampliﬁer and oscilloscope systems
R. Koyama∗1 , M. Fujimaki, N. Fukunishi, A. Goto, M. Hemmi,
M. Kase, N. Sakamoto, T. Watanabe, K. Yamada, and O. Kamigaito
The RIKEN RI beam factory (RIBF) consists of fourring cyclotrons (RRC, fRC, IRC, and SRC) and two
injectors (RILAC and AVF) which are all connectedin cascade. RILAC, AVF, and RRC began operationin the 1980s, and fRC, IRC, and SRC were installed
in 2006. Phase probes (PPs) are installed in all cyclotrons and beam transport lines of RIBF, and thebeam-bunch signals that are detected nondestructively
by these PPs are used for tuning of isochronous magnetic ﬁeld of cyclotrons and for monitoring the beamphase and beam intensity (Fig. 1). We mainly use
a newly developed system that incorporates a lockin ampliﬁer (LIA; SR844, SRS) for those tuning andmonitoring;1) however, in AVF and RRC, a conventional measurement method using an oscilloscope system (OSC; DSO6052A, Agilent) is used. In this study,
we investigated the consistency in the measurements
carried out using LIA and OSC systems.

SRC (20 PPs)

Prebuncher

G01

1st rebuncher

6A1

RILAC
ECR-ISs

to GARIS

X51
2 rebuncher
Prebuncher

M04

A01

H12
K51

S71

nd

G50

RRC (20 PPs)

3rd rebuncher

K01

D62
D15

C21

C01
AVF (6 PPs)
ECR-ISs

to RIPS
to CRIB
4th rebuncher

F51

IRC (15 PPs)

F01
fRC (14 PPs)

Fig. 1. Schematic layout of RIBF.

The block diagram of the measurement system isshown in Fig. 2. The beam-bunch signals from PPs are
divided by a power divider and transported to the LIA
and OSC and measured by them simultaneously. Using
these measured data, the beam phase and the beam
intensity are analyzed automatically by the LabVIEW
program.2)
The comparison of the isochronism of SRC (14 N7+
beam, Energy: 250 MeV/u, Frequency: 27.4 MHz)
that was evaluated on the basis of the results of threemeasurement methods is shown in Fig. 3. This ﬁgureshows the relative beam phase observed by 20 PPs,
which are radially mounted in the orbital region of
SRC. Here, “LIA-3f”is the beam phase measured using
LIA with the third harmonic of acceleration RF as its∗1

Combiner

Oscilloscope
DSO6052A

Master Oscillator
Trig.

Amp.

…

Combiner

CoaxialSwitchControl PC(LabVIEW)Power
DividerFrequency
Multiplierp SR844
Lock-in Amp.
Ref.

LAN
Network
Beam Chopper

Multi Ch.
Power Divider

GPIB/LAN

to RF Amplifiersof Accelerators

Fig. 2. Block diagram of measurement system.

Fig. 3. Comparison of isochronism of SRC on the basis ofthree measurement methods.

FC-RFQCSM

e11: Beam-bunch signals: Reference signals: Control and data

Phase Probes

to BigRIPS

Phase Probe (PP):- nondestructive- parallel plates- electrostatic induction-typee04

to Combiners

SHI Accelerator Service, Ltd.

reference signal, “FFT-3f”is the third frequency component (3f) of FFT-analyzed phase of the beam-bunch
signal measured using OSC, and “Zero cross”is thezero-cross points of the beam-bunch shape observed
using OSC (conventional method).2) We measured the
3f component of the beam-bunch signal because it had
good S/N ratio (approximately +5 dB). It was observed that the phase diﬀerences between the threemeasurement methods are less than 0.2 ns (approximately 2◦ at fundamental acceleration RF).
Figure 4 shows the FFT-analyzed phase up to the 10f
component of the beam-bunch signal measured using
OSC, together with “LIA-3f”and “Zero cross”. Since
in the LIA system, we can basically measure only one
frequency component of the beam-bunch signal,2) weneed to investigate the other frequency components.
However, from the measurements carried out in ourwork, it was found that the phase diﬀerences between
ten frequency components are less than 0.5 ns (approximately 5◦ at fundamental acceleration RF).
Figure 5 shows the beam phase and the beam intensity of a 0.669-MeV/u 136 Xe20+ beam (RF: 18.25 MHz)detected by PP-S71 (see Fig. 1) over a 4-h period. In
this case, the 5f component of the beam-bunch signal
had good S/N ratio (approximately +20 dB). The correlation diagrams of the LIA and OSC data presented
in Fig. 5 are shown in Fig. 6, and a certain degree of
linearity is observed between them.

- 136 -

1standard deviation for measurements performed after
90 s each (±1 σ), and they represent the measurement
uncertainty. We consider the voltage and phase variations, which are obtained irrespective of the error bars,
as the resolution. The error margins for LIA in Fig. 7b
are insigniﬁcant (smaller than the symbols), indicating
low measurement uncertainty in the case of LIA. The
resolution and measurement uncertainty of LIA and
OSC are summarized in Table 1.
Fig. 4. Comparison of isochronism of SRC for 1st to 10th
frequency components (1f–10f) of FFT-analyzed phase.

Fig. 5. Beam phase and beam Intensity at PP-S71 measured using LIA and OSC systems.

Fig. 7. Phase and voltage resolution of LIA and OSC using
AFG3252.

Fig. 6. Correlation diagrams for LIA and OSC data presented in Fig. 5.

Since the ﬂuctuation ranges of both the beam phaseand the beam intensity measured using OSC areslightly larger than those of the beam phase and thebeam intensity measured using LIA, we investigatedthe voltage and phase resolution of the LIA and OSC
using a function generator (AFG3252, Tektronix). Figure 7a shows the phase and voltage variation measured
using the LIA and OSC when the input phase and voltage from AFG3252 to them are varied by 0.01–0.10◦
and 0.01–0.10%, respectively, after 90 s (frequency:
18.25 MHz). Figure 7b shows 90-s average of the phaseand voltage variations plotted in Fig. 7a as a functionof the total increment in the input phase and voltage
from AFG3252. Here, the error bars in Fig. 7b are

2- 137 -

Table 1. Estimated measurement accuracy of LIA and
OSC systems.

As conclusion, the consistency in the measurement
results of LIA and OSC is conﬁrmed, as shown in Figures 3–6, and it was observed that LIA has a higher
measurement accuracy than OSC, as summarized inTable 1.
References
1) R. Koyama et al.: RIKEN Accel. Prog. Rep. 42, pp.
xviii–xix (2009).
2) R. Koyama et al.: Proc. of PASJ6, Tokai-mura, Ibaraki,
August 2009, WOOPB03, pp. 25–29.

RIKEN Accel. Prog. Rep. 43 (2010)

Radiation monitoring in the RRC and the beam distribution corridor usingioni�ation chambers
M. Nakamura, H. Watanabe, H. Okuno and M. Kase                        
Recently, many experim ents have bee n success fully
performed by using t he R IBF. However, beam l osses i naccelerators continue to pose se rious problems. T o detectbeam loss, we constructed an ionization chamber that could
be used t o monitor ra diation from t he el ectrostatic
deflection channel (EDC) of the SRC.1) In this paper, we
discuss a t rial performed to detect radiations from the RRC
and the bea m line connected to RIPS in the
beam
distribution corridor. The RRC an d the beam di stribution
corridor are ex pected to be q uite frequ ently used du ring
RIBF op erations of this year. For th e trial, we positioned
four i onization c hambers at sui table p ositions a ndsimultaneously measured the signals from these chambers.
The positions of t he ion ization ch ambers are shown i nFig. 1. The first cham ber was set nea r t he E DC of theRRC, as shown by circle a. The seco nd ch amber was set
near the phase probe (PP) in the beam distribution corridor,
as shown by circle b. The third chamber was set near thetarget for bea m frag mentation (circle c).
The fourthchamber was set near the exit of t he beam to the RIPS, a s
shown by circle d.
The size of each ionization chamber was 400 mm ☓ 250
mm ☓ 100 mm . The two electrodes in the cham ber wereconstructed us ing Al pl ates that were 1. 5 m m thick. The
dimensions of the electrodes and the distance between themin the cham bers at a) and d) were 360 mm ☓ 200 mm and       

50 mm , respectively . Before the m easurements, quite
strong signals were observed in the c hambers at b) and c ),and t hese si gnals co uld not be quantified by o ur sy stem.
Therefore, to decrease the signal i ntensity, we redu ced thesensitive reg ion by rem odeling t he electro des anddecreasing the gap between the electrodes. Thus, the sizeof the electrodes and t he distance between the electrodes in
the chambers at b) and c) were set to be 160 mm ☓ 90 mm
and 25 mm , res pectively. This ch ange d ecreased thesensitivity o f t hese ch ambers to a v alue ten ti mes s maller
than that of the chambers at a) and d). All these chambers
were filled with air at atmospheric pressure.1)
We used two a mplifiers (AMPs) to detect th e sig nals
from the ionization c hambers. T he resis tances of the se
AMPs were 1 G ǡ. FLU KE 415 B and Matsu sadaHEL-4RO.3x2-R wer e u sed to supply pow er to th e HV
electrodes of the ionization cham bers. A GRAPHTEC
GL800 data logger was used for recording signals from the
AMPs. Data were reco rded every 5 s. W e monitored
radiations during the operation of the RIBF from January 5
to 11, 2010. D uring this period, 48Ca17 was accelerated to
63 MeV/nucleon. A
Be target was use d for beam
fragmentation. During the period of operation, the voltage
supplied t o the HV electrodes of t he ionization cham bers
was 2kV.

Fig. 1. Positions of ion chambers in the RRC and beam distribution corridor.

- 138 -

Figures 2 a), b), c), and d) show the data recorded during
2010/1/8 9:00 t o 2 010/1/9 9:00 as t ypical exam ples ofrecorded data. In Figs 2 a), b), and d), the maximum valueof th e v ertical ax is was set to 2 V fo r facilitat ing easycomparison. In the case of Fig. 2 c) , t he si gnal wa s s ostrong that the maximum value of the vertical axis was set
to 16 V. In these fi gures, we ca n clearl y recognize thesignals co rresponding t o sec ondary radiations p roduced by
the 48Ca17 be am. O n t he ot her ha nd, we observe nosignals in each figure when the ion beam is stopped. The
signal at posi tion a) was be tween 0. 5 V and 1.5 V. We
could a djust t he E DC s o as to m inimize this signal a nd
extract an ion beam with th e m aximum intensity fro m th e
RRC. As shown in Fig . 2 b), the signal fro m position b)
was bet ween 0.5 V a nd 1 .5 V. However, consi dering t hesize of electrodes and the distance between t hem, which
was described above, radiations from the PP were about ten
times more in tense t han tho se fro m th e EDC of th e RRC.
The strongest signal was observed at position c) and was in
the range 1213 V, as shown in Fig. 2 c). Considering thatthe resistance of the AMPs was 1 G ǡ, the current obtainedby th is ion cha mber was est imated to be 12 13 nA. As
shown in Fig. 2 d), the signals at position d) were near 0.5 V.
This value was the sm allest among the values at t he four
positions.
In this trial, we performed simultaneous measurements ofbeam loss at four positions. If we analyze a more detailed
time p rofile of th ese four sig nals, we can d etermine t hedetailed c onditions d uring t he extraction, tr ansport, andfocusing of t he i on beam, apart f rom many ot her factors.
By positioning many ionization chambers at suitable placesin the facility, we can infer the distribution of ion beam loss
in the entire RIBF. We can use such data to make changes
to the operation of the RIBF and adjust the important partsof accelerat ors so as toensure the best conditions.
Furthermore, i f t he si gnals corresponding to beam lo ss
become too lar ge, we ca n st op t he accelerator operations
and protect the accelerators from serious damage.
Reference
1) M. Nakamura, et al.: RIKEN Accel. Prog. Rep. 42, 141(2008).

Fig. 2. Observations of signals from ionization chambers during the commissioning of the RIBF with a 63 MeV/u
48
Ca17 beam.
   The label of each figure (a, b, c, or d) is identical to the location of the ionization chamber (see Fig. 1) from
which the signals shown in the figure were obtained.

- 139 -

RIKEN Accel. Prog. Rep. 43 (2010)

Water Cooling System in Accelerator for RIBF
T. Maie, K. Kusaka, T. Kageyama, E. Ikezawa, Y. Watanabe, H. Okuno and M. Kase

RRC: RIKEN RING Cyclotron,fRC: Fixed-frequency Ring Cyclotron,

SRC: Superconducting Ring Cyclotron,

IRC: Intermediate-stage Ring Cyclotron,

INJ/EXT: Injection/Extraction, FC: Faraday Cup,

BT-Mag: Beam Transport Magnet,

CGS: Cogeneration System

Fig. 1. Water-cooling system for RIBF.

- 140 -

The water-cooling system for the RI Beam Factory (RIBF)
was newly constructed in 2004.
A schematic diagram and photograph of the water-coolingsystem are shown in Figure 1 and Figure 2, respectively.
On the other hand, the Spectroscopy with High-resoluation
Analyzer and Radio Active Quantum beams (SHARAQ)
water-cooling system was constructed in 2008, and its
operation began in 2008, and Fig.2 The SHARAQ coolingsystem was constructed in 2008. The SCRIT water-coolingsystem was constructed and its operation began in 2009.
The total operation time of the water-cooling system infiscal year 2009 was 130 days. In December, during thebeam time, the FC faction water pump (P-13) in the subsystem stopped twice because of a failure in its control
circuit, consequently, the accelerator operation was
offected.

Fig. 2.

Photograph of the cooling-water pump on the first floor
and the SHARAQ water-cooling system.

Fig. 3. Usage of cool water in Nishina Building.
The cool water, which is produced by the CGS, is sent to the Nishina and Linac buildings for various purposes,
in particular, the water is supplied not only for air-conditioning but also for accelerator operation. In addition,
the cool water from the CGS will be used in the water-cooling system of the new injector (RILAC2) in 2010.
Figure 3 shows the usage of the cool water produced by the CGS in the Nishina building.

- 141 -

RIKEN Accel. Prog. Rep. 43 (2010)

Utilities in the RI�� e�perimental �uilding
T. Fujinawa and K. Shiraishi*
1. Cranes in E20 and E21 rooms
In each experimental area in RI Beam factory,same as those in the RIBF building. All theconsiderably heavy instruments are present andcranes were installed by Sanko Setsubi Co. Ltd.
RIKEN

these are to be moved using cranes. In 2008, weandKanaden

Corporation

installed cranes for maintenance activities in a

made a contract on Crane for SCRIT in

SHARAQ room E20. The main crane installed

the E21 room. Called the “Overhead

is called "hoist type overhead traveling"crane. The crane was originally designed tomove from east to west. However, since it
was found that the movement in this direction
was not convenient for the maintenance workrequired in SHARAQ experiments, thetraveling direction of the crane was changed sothat it moved from north to south and viceversa. For this purpose, new anchor bolts wereembedded in the ceiling for adjusting the layout
for this modification. All the sophisticatedcomponents1) such as wireless systems, inverter
operation systems and other systems are theTraveling Crane with shuttle girder”, itworks asymmetrically according to the

Crane No.

§2

Type

layout

of

SR2.

SR2

is

the

main

accelerator of SCRIT and is a modified
version of AURORA. This crane is designed
such that it can be used to carry instruments aswell as be used to in the construction andmaintenance activities for an accelerator and awater cooling system. The crane and a chain
block were installed in August 2009. They are
currently in service.
Specifications of the cranes are shown in
Table 1.

Crane 2E1

Crane 2E2

Crane 2E3

Crane 2E4

Crane 2F1

SHARAQ

SHARAQ

SHARAQ

SHARAQ

SCRIT

SCRIT

Room E20

Room E20

Room E20

Room E20

Room E21

Room E21

§1

OTC

JIB

§1

JIB

§1

JIB

§3

OTC-SG

Crane 2F2

§4

TELPH

Rated Load

(t)

2.8 t

1t

1t

1t

2.8 t

2t

Span

(m)

7

-

-

-

5.3

10.5

Lift

(m)

12
Wireless

Operation

6※2

Pendant/Manual

7※1Manual

※1

5.7

4.1

7

ManualWireless

ManualRated Speed
Main Hoist(m/min)1.1/103.9

ManualManual1.1/10ManualTraverse(m/min)2.5/25

10

ManualManual2.5/20ManualTravel(m/min)0/21

Turning

Turning

Turning

2.4/24-I-250 x 125 x 10

Jib Crane

Jib Crane

Jib Crane

Travel RailAC 200 V 50 Hz 3 ph AC 200 V 50 Hz 3 phElectric Power§1：Jib Crane※1：Hoisting/Traversing：Hand Chain§2：Overhead travelling craneTurning：Pushed by Hand type
§3：Overhead travelling crane with shuttle girder ※2：Hoisting/Traversing：Pendant§4：Telpherage
Turning：Pushed by Hand type

Table 1 Crane specification*Mitsubishi Electric FA Industrial Products Corporation- 142 --

I-250 x 125 x 10/19 I-250 x 125 x 7.5/12.5
AC 200 V 50 Hz 3 phMitsubishi Electric FA Industrial Products
Corporation-

2. Water cooling system

capacity of 37 kW（800 L/min）is used for SR2.

The general plans for the water cooling system

The other pump with a capacity of 11 kW (250

for experimental facilities such as SHARAQ,

L/min) is used for a microtron, which acts as an

SCRIT and Rare-RI ring were prepared byinjector for SR2. The water pressure in bothtaking into account the estimation that eachpumps is of 0.8 MPa. An extra 37 kW pumpfacility requires 1 MW. The cooling system iswith a 1 MW cooling tower has been installed

being constructed in three stages. Flowin non-radioactive area. All electrical motors

diagrams are shown in Fig.1.

used have a high efficiency, and all motor

In the first stage, a secondary pipeline with astarters are direct connecting type2）enabling awater pump (37kW) that can carry 8,000 L/min(equivalent of 3 MW) were installed. However,quick start and an efficient restart. They also
save more “monergy” at the time of initial

the capacity of the cooling tower was only 1

installment and operation compared with

MW, and the pipe length from the experimental

inverter starter system or star- delta starterbuilding’s basement to the roof was more thansystem.

40 m. The primary cooling water pump has a

The primary water cooling line is a closed

capacity of 30 kW with a water pressure of 0.5

pipeline; this ensures that the water will neverevaporate. The system has a makeup water

MPa.
The

secondstage

ofconstruction

alarm which goes off in the event of a leakage.

iscommenced in 2009 with the installation of two
primary pumps. One of the pumps with aSH�R�� � S�RIT
�T-2

�T-1

IX

Ion-exchange resin

E

Expansion tank

�T：1,792 L/min , 1 Ｍ� each

F
T
T

Flowmeter
Thermometer
Temperture-control use
Pressure gauge

SGP ： 300

T

EP-2

T

28
℃
1,724 L/min
F

EP-1
37 kw
8,614 L/min

SGP ： 150T

HX
962 kWT

30 kW
E

T

IX

T

43℃
T

T

38
℃

SUS ： 125
T

T

F

1,060 L/min

30℃

SUS ： 125

30℃

43℃

T

(SH�R��)1,060 L/min
Rise13℃
880 kW
0.5 Ｍｐａ

2. Forextension

For extension
T

T

28℃

T

28℃
407 L/minF

HXR
726kw T

37
E

T

T

T

38℃

IX
T

800 L/min

T

T

30℃

30℃

T

HXM
227kw T

T

43℃
T

T

38℃

T

43℃

F

43℃

1,300 L/min
F

T

T

11kW

E

IX

T

43℃

F

250 L/min

30℃

T

30℃

(S�RIT)
800 L/min
Rise13℃
268 kW
0.8 Ｍｐａ(SR2)(S�RIT)
250 L/min
Rise13℃
227 kW
0.8 Ｍｐａ(Microtron)

Fig. 1 Flow diagram

Reference
1) T. Fujinawa et al: RIKEN Accel. Prog. Rep. 37 (2004) p.289-290.
2) T. Fujinawa: JOURNAL OF CIT NIHON Unv. Vol.41 No.2 (2008) ISSN 0385-4442 p.91-97.

- 143 -

RIKEN Accel. Prog. Rep. 43 (2010)

Calculation of Minimum Emittance in SR2
M. Hara, T. Hori, and M. Wakasugi[minimum emittance, electron storage ring, Chasman-Green lattice]
An electron accelerator system is under construction at the
RIKEN Nishina Center. This accelerator system is composedof the TRM (racetrack microtron), the ISOL (Isotope
Separator On-Line), and the SR2 (SCRIT-equipped RIKEN
Storage Ring)1). The electron synchrotron storage ring SR2
has the same magnetic structure as HiSOR2). Two long,magnet-free straight sections of the SR2 are prepared toinsert SCRIT devices and used for electron scattering offradioactive isotopes. The layout and specifications of the
RTM and SR2 are described in another report1). SR2 isoperated with an electron energy of 300 MeV to conduct
electron scattering experiments using SCRIT in the straightsection. Furthermore, when the ring is operated with anelectron energy of 700 MeV, it serves as a very valuable
light source in the VUV to soft X-ray region.
The theoretical minimum emittance in an electron storage
ring and that for the Chasman-Green lattice are derived.
The amplitude of the betatron oscillation (emittance) isdetermined by the equilibrium process of photon emission
and the rf acceleration which compensates the energy loss ofthe synchrotron radiation. The horizontal emittance isexpressed as(1)
where Cq = 3.84×10-13 m, Jx ≈ 1 is the damping partition
number, γ is the Lorentz factor, ρ is the bending radius, and<H> is the average of the following function over the dipole(2)
The dispersion function is generally expressed as(3)

Fig. 1 Betatron and dispersion function of Aurora II-D
(left) and of minimum emittance lattice in dipole.
The Chasman-Green (Double Bend Achromat) lattice is usedin many electron storage rings2). The lattice provides
dispersion-free section outside the pair of bending magnets.
Usually, insertion devices such as wiggler or undulators are
installed. The minimum emittance condition for the
Chasman-Green lattice is also derived and applied for SR2,
which can have only one cell. Double-bend achromat
condition gives a = 1 and b = 0 in the eq. (4).
⎛ sin θ 1 sin(2θ − 2θ 0 ) + sin 2θ 0 1
sin(θ − 2θ 0 ) + sin 2θ 0 ⎞H (s) CG min = β 0 ⎜1−−− cos 2θ 0 +
⎟
⎠
⎝
θ
θ
4
2
θ

The betatron function is generally expressed as,+(4)
The betatron function is assumed to have a minimum
value β0 at s = s0 in the bending magnet. The otherfunctions, namely, ηx’, γx and α are derived and equation(2) can be estimated. The <H>dipole can be expressed as aquaduratic equation using ρ, lB, θ, s0, a, b, and β0. For
given ρ, lB, and θ, the minimum condition gives a = sinθ /θ and b = (cosθ - 1) / θ. With this condition, β0 for isdetermined for any θ0(θ0 = s0 / lB). Among these θ0 values,
θ0 = θ / 2 gives minimum emittance.
andwhen θ<<1, the minimum emittance is expressed as ε =Cqγ2θ3 / 12√15, where β0 = ρθ/2√15.
For SR2(θ = π), a = 0, b = -π/2, θ0 = π/2, and β0 = 0.38
m gives the minimum emittance of ε = 0.4 π mm•mrad.
In Fig. 1, the dispersion and betatron functions in the
dipole calculated using these parameters are icomparedwith the HiSOR parameters. Both functions are very
similar, and HiSOR and SR2 are designed to achieve
emittance minimum.

(7)

sin(θ − 2θ 0 ) + sin 2θ 0 ⎞ρ 2 ⎛ sin θ 1 sin(2θ − 2θ 0 ) + sin 2θ 0 1++ cos 2θ 0 −
⎜1−
⎟
⎠
β0 ⎝
θ
θ
4
2
θ

When θ is π, minimum emittance condition gives θ0 of alittle smaller than 3θ/8.
When θ<<1, as is well known, minimum condition gives θ0= 3θ/8 and ε = Cqγ2θ3 / 4√15 where β0 = ρθ√3 / 8√15.
Minimum emittance value becomes three times larger by
the additional condition of zero dispersion.
References

1) M. Wakasugi et al.: in this Accelerator Progress Report.
2) R. Chasman et al.* IEEE Trans. Nucl. Sci. NS-22, 1765(1975).
S.Y. Lee et al.: Proc. of 1991 PAC, p. 2679.

(5)(6)- 144 -

RIKEN Accel. Prog. Rep. 43 (2010)

Capability of SR2 as a compact synchrotron radiation source
T. Hori, M. Hara and M. Wakasugi
An electron accelerator system which consists of 150
MeV racetrack microtron injector and 700 MeV compact
storage ring is under construction at E21 experimental roomof RIBF as SR2 (SCRIT-equipped Riken Storage Ring)
aiming at electron scattering experiments for short-lived
unstable nuclei using the SCRIT technique1). In the past thesystem was developed and operated at Tanashi Works of
Sumitomo Heavy Industries, Co. Ltd. (SHI) as
AURORA-2S2) (A2S) having a racetrack orbit of 11 m
circumference with a Q-singlet in each straight section. A2S
was transferred from SHI to RIKEN last summer after
modified to AURORA-2D3) (A2D) as 22 m circumferencewith two Q-doublets in each extended straight section,
where a free space of 2 m in length is reserved for inserting
various devices.
In addition to the major purpose mentioned above, SR2 isto play another role at Nishina Center as a compact
synchrotron radiation (SR) light source in VUV~ soft X-ray
region. The basic configuration of SR2 is the same as theSR light source HiSOR4) in Hiroshima University, except
for the insertion devices of two undulators which are mainly
used for high-resolved photo emission spectroscopy (PES).
Therefore, SR2 is applicable to the similar research
activities as HiSOR, namely, in solid state physics, in photochemistry, in molecular biology, etc. However, A2S hadoriginally been designed as a light source for X-ray
lithography, thus the SR2 system might be much suitablefor developing micro/nano fabrication technology. The SR
spectra from SR2 bendings are shown below (Fig. 1), where
the critical photon energy 0.87 keV (1.24 nm wavelength).

rather short, a few meters, compared with those for basic
researches like PES, etc. The following picture shows theseBLs connected to A2S in SHI’s Tanashi Works (Fig. 2).
Some of them are planned to be re-joined to SR2 in the next
fiscal year.

Fig. 2. Photo of micro/nano fabrication BLs at Tanashi.
As for SR2, each bending magnet provides 10 connection
ports for BLs, besides the extraction port from the straightsection. There is a thick pillar, however, in front of abending magnet called M2. Only SR emitted from the otherbending M1 is available for conjunction to user’s BLs.
Right now 4 ports are reserved for such BLs as the SR fromM1 with more than 10-m length of alignment space for BL
components. A few ports will be available in addition withmuch shorter spaces (~5m) for BL settings. These optional
ports might be adequate for BLs LIGA/TIEGA.
In the next fiscal year, the SCRIT system will be installed
into one straight section. Another straight section would bevacant for subsequent several years. It means that there is apossibility to develop insertion devices to improve SR fromthe compact ring by exploiting this time interval. Routine
operation of SR2 for SR users with the designed intensity,
which means 300 mA stored beam, will be ready in 2011.
References

Fig. 1. SR spectra from bending magnets of SR2.
While transferring A2S, beam lines (BLs) for LIGA
(Lithographie, Galvanoformung, Abformung)5) and TIEGA(Teflon Induced Etching and Galvanicforming)6) weremoved simultaneously from SHI to RIKEN. These BLs are1) M. Wakasugi et al., Phys. Rev. Lett. 100, 164801 (2008).
2) D. Amano et al., Proc. EPAC2000, Vienna (2000) p.604.
3) T. Hori et al., Proc. 11th Symp. on Accel. Sci. & Tech., Hyogo,(1997) p.534.
4) http://www.hsrc.hiroshima-u.ac.jp/hisor.htm5) S. Sugiyama et al., Microsystem Technol. 4, 61 (1998).
6) T. Katoh et al., J. Synchrotron Rad. 5, 1153 (1998).

- 145 -

RIKEN Accel. Prog. Rep. 43 (2010)
Magnetic plasma confinement for laser ion source†
M. Okamura1, T. Kanesue2, and K. Kondo3
The direct plasma injection scheme (DPIS), which uses alaser ion source (LIS) and a radio frequency quadrupole
linear accelerator (RFQ), was recently developed toaccelerate intense heavy ions. In this scheme, a high-power
laser is focused onto a solid-state target to produce dense
plasma, which contains highly charged ions. The laserproduced plasma expands in a direction perpendicular to thetarget surface, and this expansion causes an increase in theplasma pulse width and a decrease in the current density.
Since the plasma spreads three dimensionally, the plasma
pulse length is proportional to the drift distance L and theion current density is proportional to L-3. After drifting, theions are extracted from the plasma at the entrance of the
RFQ and are accelerated to the design energy. We havealready accelerated aluminum and carbon beams withcurrents greater than 60 mA using the DPIS1). Although thepeak current is high, the pulse width of the beam is too
small for some applications, for example, as a beamprovider for a large synchrotron. We can easily increase thepulse width by increasing the plasma drift distance;
however, the current injected to the RFQ becomes verysmall. To prevent this reduction in the current, the use ofsolenoidal magnetic confinement was tested. The presenceof an axial magnetic field decreases the transverse
expansion of the plasma and thereby leads to a high density
during the expansion2,3).
To verify this scheme, a simple coil comprising a 2-mm diameter wire directly wound on a beam pipe wasconsideered. The inner diameter and the length of the coilwere 76 mm and 480 mm, respectively.

Fig. 1 Experimental setup
To observe the effect of the solenoid, a graphite target andother equipment were assembled. A suppressor mesh wasplaced before the Faraday cup to distinguish the ions fromthe laser plasma. The laser power and laser pulse duration
were 0.9 J and 7 ns (FWHM), respectively.
†

Condensed from the article in Review of Sci. Inst.. 81, 1 (2010)
Brookhaven National Laboratory
2
Department of Applied Quantum Physics and Nuclear Engineering,
Kyushu University
3
Department of Energy Science, Tokyo Institute of Technology
1Fig. 2 Enhanced current in the case of a multi-charged
carbon beam.
The effect of the solenoid was clearly seen when thesolenoid current was increased. A typical current waveformtaken by the Faraday cup is shown in Fig. 2. The charge
states vary from 3+ to 6+, with the highest yield of charge
state being 4+. To avoid a discharge between the
suppression mesh and the Faraday cup, a collimator with an
opening diameter of 1.55 mm was installed at a distance of
803 mm from the target. Above 50 G, the plasma current
density became too high to pass through the biased mesh,which was connected to a voltage source of -4.5 kV. Thisshows that the ions and the electrons are not separated, andthe space-charge repulsion force can still be compensated in
the presence of the axial magnetic field. We might be able
to apply a longer solenoid field in order to extend the beampulse duration. It was seen that a 46-G field increased thepeak value by approximately four times.
It was confirmed that a solenoid can effectively enhance
the ion density, and the technique can be used in the DPIS.
Furthers, the solenoid may improve any LISs. By applying
a programmable pulsed power supply to the solenoid, wemight be able to control the current shape by changing thesolenoid current.
References
1) M. Okamura, T. Takeuchi, R. A. Jameson, S. Kondrashev, H.
Kashiwagi, K. Sakakibara, T. Kanesue, and J. Tamura, Rev. Sci.
Instrum. 79, 02B314 (2008)
2) J. Wolowski J. Badziak, I. Ivanova-Stanik, P. Parys, W.
Stepniewski, and E. Woryna, Rev.Sci. Instrum. 75, 1356 (2004)
3) Y. Y. Tsui, D. Vich, and R. Fedosejevs, Appl. Phys. Lett. 70(15), 14 (1997)- 146 -

RIKEN Accel. Prog. Rep. 43 (2010).


 ＊ ＊ ＊ ＊ ＊        
          
       
       
          


       
        
∝                                ∝                                               
          
        



       
                             
          
        
                               
                
          


       
 
       
＊ ＊ ＊ 
＊    


         
 
         
                
                












         












                     





 

- 147 -

RIKEN Accel. Prog. Rep. 43 (2010)

Particle simulation for direct plasma injection in an RFQ matching section †J. Tamura,∗1,∗2 T. Hattori,∗1 N. Hayashizaki,∗1 T. Ishibashi,∗1 T. Kanesue,∗3 H. Kashiwagi,∗4 K. Kondo,∗1 andM. Okamura∗5
The Direct Plasma Injection Scheme (DPIS) has beenused in radio frequency quadrupole (RFQ) linacs, and highintensity heavy-ion beams have been generated and accelerated.1) By using the DPIS, a C6+ beam with a maximum beam current greater than 10 mA has been accelerated from 20 keV/nucleon to 100 keV/nucleon.2) One of
the most unique features of the DPIS is that the ions are
extracted from plasma at the RFQ entrance. This meansthat in the RFQ radial matching (RM) section, ions areforced by both the electrostatic ﬁeld generated by the extraction electrode and the RF electric ﬁeld generated by
the RFQ electrode. On the other hand, in the conventional
beam injection scheme used in RFQ linacs, ions are forced
only by the latter ﬁeld. To describe the evolution of thebeam extracted from the laser plasma in the RM section,
we performed particle tracking simulation using a threedimensional particle-in-cell method.3,4) In this simulation,
we made the following assumptions,Fig. 1. Particle distribution for the beam current of 6 mA (x = 0
plane).

• The extracted beam comprises only C6+ ions.
• The plasma sheath is ﬂat and perpendicular to thebeam axis.
• Initially, the beam is axisymmetric and uniformly distributed in real space.
As mentioned above, the external ﬁeld in the RM section consists of both the electrostatic ﬁeld and the RF electric ﬁeld. The potential maps for these ﬁelds were obtainedusing KOBRA3-INP.5) The quadrupole symmetry is maintained throughout the RM section.
Particles of different beam currents of 6 mA, 30 mA,
60 mA, and 90 mA are tracked. Figure 1 shows the particle
distribution in the x = 0 plane for the beam current of 6 mA.
To visualize the geometry clearly, particles that satisfy thecondition x2 + y2 > (aperture radius of the RFQ electrode)2
are not displayed. The transmission efﬁciency to the adjacent normal RFQ cell is about 37%, 29%, 24%, and 19%
for the beam currents of 6 mA, 30 mA, 60 mA, and 90 mA,
respectively. Even in the case of the relatively low beam
current of 6 mA, ions are not captured by the RFQ. The
reason they are not captured is that the electrostatic ﬁeld
generated by the extraction electrode has a divergent component. To avoid this divergent component, the beam has
to be focused initially. Figure 2 shows an example of an
initially convergent beam in the DPIS.
From these simulations, so as to avoid the radial defocusing force which is particular force in DPIS we found
†
∗1
∗2
∗3
∗4
∗5

Condensed from the article in Rev. Sci. Instrum. 81, 02B726 (2010)
Tokyo Institute of Technology, JapanRIKEN, Japan
Kyushu University, Japan
Japan Atomic Energy Agency, Japan
Brookhaven National Laboratory, United States

Fig. 2. Particle distribution for the beam current of 6 mA (x = 0
plane) when the beam is initially focused.

that it is necessary to provide a more convergent beam in
the DPIS than usual RFQ injection. The initial condition of
the extracted beam is decided by the shape of the plasma
sheath which mainly depends on the plasma density. The
plasma density can be varied by changing the plasma drift
length.6) The longer the laser plasma drifts, the lower is thedensity of plasma injected into the RFQ. In the DPIS, weneed to optimize the plasma density to realize a concave
ion-emitting surface which produces a convergent beam.
References

1) M. Okamura et al.: Rev. Sci. Instrum. 79, 02B314 (2008).
2) H. Kashiwagi et al.: Rev. Sci. Instrum. 77, 03B305 (2006).
3) R. W. Hockney and J. W. Eastwood: Computer Simulation Using Particles (Taylor & Francis Group, New York, 1988).
4) C. K. Birdsall and A. B. Langdon: Plasma Physics via Computer Simulation (Taylor & Francis Group, New York, 2005).
5) P. Spädtke: KOBRA3-INP USER MANUAL WINDOWSVERSION 4.43 (INP).
6) T. Kanesue et al.: Rev. Sci. Instrum. 81, 02B723 (2010).

- 148 -

RIKEN Accel. Prog. Rep. 43 (2010)

Design research of laser ion source for RHIC-EBIS†
K. Kondo,� 1 T. Kanesue,� 2 J. Tamura,� 1 and M. Okamura� 3[Laser ion source, Electron-beam ion source, Relativistic heavy-ion collider](1)j ∝ L−3 ,(2)(3)

t ∝ L,N ∝ L−2 ,where j, L, t and N are current density, plasma drift
length, beam pulse duration and particle number, respectively. To satisfy the requirements of limited low
current for LEBT and suﬃcient particle number for
RHIC-EBIS, we use the solenoid to enhance the beam
current and total ion yield. For an enhancement factor
α, we can rewrite Eqs (1) and (3) as follows:j ∝ αL−3 ,N ∝ αL−2.

number of singly charged ions, Nmin , to N0 . Table
1 lists the beam properties at L = 5 m for � ve ion
species: Al, Si, Fe, Ta, and Au; these are the typicallyspecies required for National Aeronautics and Space
Administration Space Radiation Laboratory (NSRL)
science programs and Au ions collision in RHIC.
It is desirable that LIS optics be located far awayfrom the vacuum target chamber to prevent damage
to the optics by laser ablation. A galvano mirror with
an operation time of a few hundred microseconds isused for changing the direction of laser irradiation to
obtain di� erent ion species. In Fig.1, we show a sketchof LIS, which is a primary ion source for RHIC-EBIS,with its optics arrangement and the solenoid.
The solenoid in the LIS is useful since it helps satisfy
the requirements of both low peak current and suﬃcient particle number. It is suitable to use this LIS
system, with optics as shown in the � gure, as the primary ion source of a singly charged ion beam.
Table 1. Beam properties for RHIC-EBIS.
Ion species
Pulse length t [µs]Enhancement factor α
N0 (×1010 )Overall eﬃciency β %

(4)
(5)

The relationship between t and L does not depend on
the solenoid � eld; no signi� cant change was observed
in t in the presence or absence of the solenoid2) .
We assume that for a realistic design of the LIS, L,
the distance between solid target and extraction pointis 5 m and laser power density is 2.0 × 108 W/cm2 .
Peak current, pulse width, and particle number at L
= 5 m in the absence of the solenoid can be derived
from the experimental results3)4) corresponding to L
= 1 m by using Eqs (1), (2), and (3). The numberof 1+ charged ions, N0 , injected by using the solenoid
is determined by considering the value of α at L = 5m; the value of α can be � xed so that the requirementof limited current for LEBT is satis� ed. The overall
eﬃciency β, which is de� ned as the required ratio of
the net ion number before and after RHIC-EBIS, isdetermined by considering the ratio of the minimum

� 2
� 3

Gl

ase

r

Si
180
15
6.5
66

Fe
220
6.6
5.2
46

Ta
280
116
5.2
35

Au
430
3.6
5.3
32

Convex lensf = 5000 mm

Galvano mirror
for y-axisyz

Galvano mirror
for x-axis
3m

x

fro
to m ta
co rg
7w
nv et
ind
ex
ow
len

BK

s

Targetchamber

Solenoid

5 m from target
to extraction point

Targets� 1

Condensed from the article in Rev. Sci. Instrum. 81,
02A511 (2010)
Department of Energy Sciences, Tokyo Institute of Technology
Department of Applied Quantum Physics and Nuclear Engineering, Kyushu University
Collider-Accelerator Department, Brookhaven National
Laboratory

:YA

Al
190
11
6.1
75

Plasma†Nd

Y

At present, it is not feasible to use the Laser Ion
Source (LIS) as a primary ion source for Relativistic
Heavy Ion Collier-Electron Beam Ion Source (RHICEBIS)1) because the requirements of both limited low
current for Low-Energy Beam Transport (LEBT) andinjection of a suﬃcient number of 1+ ions, cannot besatis� ed at the same time. However, the results of LIS
experiments in which a solenoid is used show that thebeam current and total ion yield are enhanced2) . We
derive an appropriate condition for RHIC-EBIS witha solenoid.
In the LIS, the following relationships hold.

Fig. 1. Sketch of LIS for RHIC-EBIS.

References
1) J. Alessi et al.: Proc. of LINAC 2006, P.385.
2) M. Okamura et al.: Rev. Sci. Instrum. 81, 02A510(2010).
3) T. Kanesue et al.: Proc. of EPAC 08, P.421.
4) T. Kanesue et al.: Rev. Sci. Instrum. 79, 02B102 (2008).

- 149 -

RIKEN Accel. Prog. Rep. 43 (2010)

Laser Beam Recycler with Asymmetric Confocal Cavity
I. Yamane, M. Nakamura, and H. Okuno[ion beam, charge-exchange, laser stripping]
Against the b ackground of rapid pr ogress of laser
technology, there i s co nsiderable ex pectation t hat laser
beams may be applied for ion-beam stripping. As describedin the r eference1), calculations based o n Gaussian b eam
optics s uggest that for a high-power laser b eam, b eam
stacking can be ach ieved at t he c onfocal poi nt of anasymmetricconfocalcavity.
Although s imilargeometrical-optics-based studies2,3) were p erformed o nbeam s tacking i n a n asymmetric confocal cav ity, in t hese
experiments, the enhancement of beam intensity by stacking
was n ot obs erved. The e xperiment de scribed i n t his pa per
was p erformed in o rder to e xamine the r esults o f
calculations based on Gaussian beam optics.

Fig. 1, Asymmetric confocal cavity and beam path

constant. Therefore, when a continuous or pulsed beam witha p eriod e qual t o i ts r epetition period i n t he c avity i s
injected, all reflected laser beams in the cavity converge at
a at t he s ame t ime, and t he beam i ntensity increases
considerably. We cal l s uch a cavity as a “laser-beamrecycler”. As described in the reference1), when a Gaussian
beam w ith a w aist a t c0, and Rayleigh range f1, thatis, π wc20 λ = f1 , is injected, the beam returns to a as a waist
every t ime, an d t he beam i ntensity s tacks u p. H ere, wc0 is
the half w idth a t 1/ e2 of the p eak at c0, and λ is the
wavelength o f t he i njected l aser beam. H owever, because
the b eam size at a gradually i ncreases with t he number o fturns, the beam intensity for the given useful beam diameterincreases and reaches a saturation level. As is shown in Fig.
2, the intensity of a b eam o f radius of 2 wc0 may be 25 ormore t imes of t he i njected-beam i ntensity. T his highintensity makes t he l aser b eam useful i n various
applications such as in a laser neutralizer for high-energy Hbeam substitute for t he m agnetic n eutralizer used in be am
splitting4).
As the first step of the experiment, we measured t heevolution of the ha lf w idth a t 1/e2 of the p eak to clarify
whether the laser beam is Gaussian. As is shown in Fig. 3,
the M2 factor of the laser beam is estimated to be 1.04, andthe beam is confirmed to be nearly Gaussian.

When a laser b eam is injected into a n a symmetricconfocal cavity such that the beam is parallel to the axis of
the c avity, a s shown in F ig. 1, i t repeatedly f ollows t hetriangular path, a → bｎ → cn → dn → a, in the cavity andreturns to the confocal point a after every loop.

Fig. 3, Measured and calculated evolution of the half width
at 1/e2 of the peak.
References

Fig. 2, Evolution o f beam i ntensity w ith beam radius ν (=radius/wc0). The u nit o f the stacked-beam i ntensity i s t heinjected-beam intensity. k is the ratio f２/f1.
If t he path o f the i njected beam i s s ufficiently c losed t o
the axis of the cavity, the r epetition p eriod remains almost

1) I. Yamane a nd H . O kuno: KEK Re port 2009-9, N ovember
2009.
2) S. Amano and T. Mochizuki: Jpn. J. Appl. Phys. 40, 654 (2001).
3) A . J . R ollason, X . F ang, D . E. D ugdale: Nucl. I nstr. Meth. In
Phys. Res. A 526, 560 (2004).
4) A . F acco, R . Paparella, D . Berkovits, I. Yamane: PRSTAccelerators and Beams 10, 091001 (2007).

- 150 -

7.

Instrumentation

RIKEN Accel. Prog. Rep. 43 (2010)

Status of the BigRIPS and ZeroDegree Project
T. Kubo, K. Kusaka, T. Ohnishi, K. Yoshida, A. Yoshida, N. Fukuda, M. Ohtake, Y. Yanagisawa, H. Takeda, N. Inabe, D.
Kameda, and K. Tanaka
The status of the major research instruments in the RI
beam factory (RIBF), such as the BigRIPS in-flight
separator,1,2) the ZeroDegree spectrometer,3) and thehigh-resolution beamline for the SHARAQ spectrometer,4)is presented in this report. A schematic layout of the major
research instruments is shown in Fig. 1 along with thecyclotrons at RIBF.
The BigRIPS separator is composed of fourteen superconducting triplet quadrupoles having large apertures(STQ114) and six room-temperature dipoles (D16).
There are seven focuses (F17). One of the importantfeatures of BigRIPS is its large acceptance, which results inefficient production of RI beams by not only projectile
fragmentation of various heavy-ion beams but also in-flightfission of a uranium beam. This feature was achieved byusing the large-aperture superconducting quadrupoles.
Another important feature is its two-stage structure. The
first stage consists of the components between the
production target (F0) and F2, while the second stage
consists of those from F3 to F7. The section from F2 to F3
acts as an ion-optical matching section between them. Thisfeature allows a separator-spectrometer mode as well as a
two-stage separation mode. In the former mode, RI beams
are separated using an energy degrader in the first stage,
while the second stage works as a spectrometer to identify
the RI beams. The second stage is designed to have good

momentum resolution so that RI beams can be identified
without having to measure total kinetic energies eventhough ions are not fully stripped at the RIBF energies. In
the two-stage separation mode, an energy degrader is usedat both stages to purity the RI beams further.
There is a focal-plane chamber in each focus that
accommodates various beam-line devices and detectors
used for diagnostics and particle identification (PID). The
PID scheme is based on the E-TOF-B method in which
trajectory reconstruction is used to improve momentum
resolution. The primary beams stops at a high-power beam
dump located at the first dipole D1. A water-cooled
rotating-disk target is used to cope with high-power beams.
The first stage is surrounded by concrete radiation shields
that weigh about 7000 tons.
The RI-beam delivery line that follows the BigRIPS is
designed not only for the transportation of RI beams toexperimental setups but also for use as a forward
spectrometer that has been named ZeroDegree. The delivery
line consists of nine STQs (STQ1523), two dipoles(D78), and five focuses (F812). The section from F8 to
F11 forms the ZeroDegree spectrometer, while that from F7
to F8 is acts as an ion-potical matching section between the
BigRIPS and ZeroDegree. The magnets of ZeroDegree havethe same design as those of BigRIPS. There is a focal-planechamber in each focus to accommodate various beam-line

High-resolution beam line

Fig. 1. Schematic layout of the RI Beam Factory in 2010.

- 151 -

devices and detectors used for diagnostics and PID, as in
the BigRIPS separator. A secondary target is placed at F8
when the delivery line is used as the ZeroDegree
spectrometer for reaction experiments with RI beams. The
ZeroDegree is used to analyze and identify projectile
reaction residues often in coincidence with -rays that aremeasured by an array detector surrounding the target. The
ZeroDegree can be operated in different optics modes
depending on the experimental requirements.
The high-resolution beamline extends from F3 to D6 (theexisting part) and from D6 to the SHARAQ target position(the new part). The new part is composed of three STQs
(STQH1415,
STQH19),threeroom-temperature
quadrupoles (QH1618), two dipoles (DH78), and four
focuses (FH710). The beamline can be operated in a highresolution dispersive mode so that the dispersion matchingconditions can be attained at the SHARAQ focal plane, thus
allowing high-resolution measurements using the SHARAQ
spectrometer.
The BigRIPS and the ZeroDegree became operational in
May 2007 and November 2008, respectively. The
high-resolution beam line was commissioned in March2009 together with the SHARAQ spectrometer.
In December 2009, the BigRIPS and the ZeroDegree
were used for experiments using a 238U beam and a 48Ca
beam at 345 MeV/u. In-beam -ray spectroscopy forneutron-rich exotic nuclei was performed using RI beams of
130132
Sn.  spectroscopy was performed for several
neutron-rich exotic nuclei around 106Sr. These isotopes
were produced via in-flight fission of the 238U beam.
Interaction cross sections were measured for a wide rangeof neutron-rich Ne isotopes that were produced by projectile
fragmentation of the 48Ca beam.
In the commissioning experiments for the high-resolution
beam line and the SHARAQ spectrometer in March and
May 2009, the dispersion matching was successfully tested
using primary beams and RI beams. In November 2009, thefirst nuclear physics experiment at SHARAQ was carriedout using a triton beam produced from a 4He beam at 320
MeV/u. A (t,3He) reaction was studied to investigate
isovector spin-monopole excitation. Details of the
SHARAQ experiments are presented elsewhere.

Fig. 2. Photograph of the beam-dump pillow seal withradiation shields that was installed between D1 and STQ2.

In order to cope with high-intensity primary beams,
pillow seals and radiation shields have been installedaround the beam dump and the production target in the firststage of the BigRIPS separator. The pillow seals allow
remote disconnection of beam pipes and significantly
facilitate the handling and maintenance of the devices underhigh residual radiation. The radiation shields are used toshield light charged particles and neutrons emitted from thebeam dump and the target in order to protect the STQs
against radiation damage and to reduce the radiation heatloads on them. Figure 2 shows a photograph of thebeam-dump pillow seal that was installed between D1 and
STQ2. The pillow seal is surrounded by the radiation
shields made of heavy metal and steel. In summer 2009,
some concrete shielding blocks were removed from the firststage, and the pillow seals and radiation shields were
installed.
The operation of the BigRIPS cryogenic plant, which isused to cool STQ15, has been very stable as a result of the
upgrade of the oil-removal unit of the compressor. The
operation of the cryo-coolers, which are used to cool therest of the STQs, has also been stable.

Fig. 3. Nuclear chart that shows new isotopes produced byin-flight fission of a 238U beam at 345 MeV/u. New isomers
observed in the same experiment and the r-process path arealso shown.
The analysis of the new-isotope search experimentconducted in November 2008, which was performed using a
238
U beam at 345 MeV/u, has almost completed. We
observed 42 new neutron-rich isotopes and 13 new isomers
over a wide range of atomic numbers, as shown in Fig. 3.
More detailed reports on the project have been provided
elsewhere in this progress report.
(Note that the number of observed new isotopes is 45 in
our paper published recently.)
References
1) T. Kubo: Nucl. Instr. and Meth. B 204, 97 (2003).
2) T. Kubo et al.: IEEE Trans. Appl. Supercond. 17, 1069
(2007).
3) Y. Mizoi et al.: RIKEN Accel. Prog. Rep. 38, 297 (2005).
4) T. Kawabata et al.: RIKEN Accel. Prog. Rep. 41, 129(2008).
5) T. Ohnishi et al.: J. Phys. Soc. Japan 77, 083201 (2008).

- 152 -

RIKEN Accel. Prog. Rep. 43 (2010)

Upgrading the BigRIPS target chamber
Atsushi Yoshida, Tetsuya Ohnishi, Yoshiyuki Yanagisawa, Kensuke Kusaka and Toshiyuki Kubo
The target chamber for the production of RI beams in the
projectile fragment separator (BigRIPS) has been upgraded
for two reasons. Firstly, to facilitate chamber replacement,
pillow seal devices were installed at the beam ductconnection of the target chamber. Secondly, to reduce theheat load on an air-core-type superconducting triplet
quadrupoles magnet1) (STQ1), a beam scraper was installedat the downstream wall of the target chamber.
The target chamber was designed such that it included a
replaceable unit structure that facilitates maintenance undera high-radiation environment.2) All the target systemcomponents assembled in the chamber can be replacedusing a remote-handling maintenance cart. However, whena fatal malfunction occurs at the chamber itself or at theneighboring STQ1 magnet located downstream, it must be
possible to disconnect the chamber from the beam line
easily. The pillow seal device3) consists of a seal-face flange,
inflatable bellows, and inflatable thin metal diaphragms
similar to a balloon pillow. A vacuum-tight duct connection
is established by supplying air pressure to the device. Thus,a vacuum duct can be remotely disconnected without
unscrewing bolts. Two pillow seal units 4) were installed at
the beam duct connections of the chamber (Fig. 1). Pillow
seals with inner diameters of 110 mm and 250 mm were
mounted at locations up- and downstream of the beam duct,
respectively. The downstream pillow seal has water ways
inside the flanges to deal with the heat load from the target.
Its operating air pressure is 0.35 MPa which is required toinflate both bellows and diaphragms. The measured vacuum
leak rate for He gas was lower than the background level of
1×10-9 Pa*m3/sec.

Fig. 1. Pillow seal devices installed at beam ductconnections upstream (left) and downstream (right) on thetarget chamber. In the photos, A, W, and V represent utility
pipes used to supply air pressure, to supply water forcooling, and to create vacuum for differential pumping,respectively.

At the target used for producing secondary RI beams, alarge number of high-energy light-charged particles andneutrons are also produced. These undesired particles affectthe heat load on the neighboring STQ1 magnet. To reduce
the heat load, a beam collimator, the so-called “scraper”,
was used to scrape off these particles from a bundle of themain secondary beam. A prototype scraper was designed(Fig. 2) considering the limited space between the walls of
the target chamber and STQ1. A possible solution is toinsert a cylindrical structure into the downstream pillow
seal. The structure has a beam collimation hole with adiameter of 36 mm, which corresponds to ±5° (±87 mrad)with respect to the target position. Note that this angle issufficiently larger than the angular acceptance of the
BigRIPS separator, which is ±40 mrad and ±50 mrad in thehorizontal and vertical directions, respectively. The materialof the scraper should be as heavy as possible in order tostop high-energy light-charged particles, mainly fragmented
protons with a maximum energy of 350 AMeV. For the
prototype, we used copper with a thickness of 126 mm,
which is grater than the proton range of 110 mm.
Range( p 350AMeV in W) 66.2mm
Range( p 350AMeV in Cu) 109.5mm
Cylinder Axis length = 126mm

Fig. 2. Prototype scraper installed in the target chamber(left). Its typical dimensions are shown (right). It consists of
inner (1) and outer (2) scraper blocks weighting 30 kg and
29 kg, respectively. The inner block will be disassembled
using the remote-handling maintenance cart.
The heat load was estimated using PHITS 5) simulation
code. The inner structure of STQ1 cryostat was modeled.
The bombardment of a 15 mm thick beryllium target by anintense 1 pμA 48Ca beam was simulated. Fig. 3 shows the- 153 -

flux distribution of protons, neutrons and nuclei inhorizontal cross sectional view. Here, the nuclei include
various nuclei for which 1 < Z < 20. Note that each flux
includes secondary protons, neutrons, and nuclei producedin high-energy cascade processes. The bundle of secondary
beams (Fig. 3a) passes through the beam hole of the scraper.
The protons (Fig. 3c) emitted at the forward angle passthrough the beam hole as well, whereas most of the protons
emitted at angles with magnitude grater than 5° are stopped
in the scraper or 6 cm-thick aluminum wall of the target
chamber. It is clear that for high-energy neutrons (Fig. 3b),the limited thickness of the scraper is not effective.

helium vessel and inner vacuum duct near the beam axis. In
this simulation, the magnetic rigidity of STQ1 was
optimized for a main secondary 31Ne beam. Then, thetrajectories of protons and light-charged particles, whichhave smaller magnetic rigidities, were over-focused in
STQ1. This can be seen in Fig. 3c; some of these protons hit
the inner vacuum duct.
The heat load calculated with and without the scraper are
listed and compared in Table 1. The sub total of the heatload on the components assembled in the region at 4 K
decreased from 460 W to 298 W because of the scraper. It
has been reported 6) that the excess cooling capacities forthe load at 4 K region in the BigRIPS cryogenic plant were
measured as 322 W. This excess capacity should be sharedby five STQ magnets, including STQ1, in the beam line.
Although the main heat load sources are expected to be
STQ1 and STQ2, the present heat load on STQ1 should be
sufficiently smaller than the excess capacity. We areplanning to measure the actual heat load during experiments
by using an intense 48Ca beam; we also plan to compare thevalues with the simulation results mentioned above. To
optimize the final design of the scraper, we should decrease
the diameter of the beam hole and use a heavier material
like tungsten.

Table 1. Heat load calculated with and without the scraperfor various inner components of STQ1 cryostat.
References

Fig. 3. Calculation results obtained using the PHITS code.
The flux intensities of a) nuclei, b) neutrons, and c) protons
are plotted in units of [1/cm2/source]. The heat loadintensity d) is plotted in units of [MeV/cm3/source]. Here,the normalization factor “per source” means “caused by one
nucleus of primary 48Ca beam”.
The total heat load generated by all particles is plotted inFig. 3d and listed in Table. 1. The largest heat load appears
at the scraper. The next largest heat load appears at the1) K. Kusaka et al.: RIKEN Accel. Prog. Rep. 37, 297 (2004).
2) A. Yoshida et al.: RIKEN Accel. Prog. Rep. 41, vii (2008).
3) Y. Yamanoi et al.: Proc. 2nd Annu. Meet. of Particle Accelerator
Society of Japan and the 30th Linear Accelerator Meeting inJapan, Tosu, Japan, 2005-6, 736 (2005).
4) Fabricated by Mirapro Co. LTD. , http://www.mirapro.co.jp/
5) H. Iwase, K. Niita, and T. Nakamura; “Development of General
Purpose Particle and Heavy Ion Transport Monte Carlo Code”,
J.Nucl. Sci. Technol., 39, 1142 (2002).
6) K. Kusaka et al.: RIKEN Accel. Prog. Rep. 41, 244 (2008).

- 154 -

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Status of the Control system of BigRIPS
K. Yoshida, T. Ohnishi, K. Kusaka, A. Yoshida, Y. Yanagisawa, N. Fukuda, M. Ohtake, H. Takeda, D. Kameda,
N. Inabe, K. Tanaka, and T. Kubo
The control system of BigRIPS1) is based on theexperimental physics and industrial control system(EPICS)2) ; it was constructed in 2007 and has since
been operated without any sever failures. The statusof magnets, cryostats, beam diagnostic devices, andvacuum pumps is constantly recorded by the channel archiver utility through out the year, regardlessof whether BigRIPS is in operation. Up to 13GB ofdata are archived in one year.
Over the last two years, two major modiﬁcations
were made to the control system. First, the controlof the high-resolution beam line for SHARAQ spectrometer is added to the control sysytem. The highresolution beam line consists of two dipole magnets,
three superconducting quadrupole magnets (STQs),
four normal-conducting quadrupole magnets, four focus chambers, and six vacuum pump stations. Eachfocus chamber is equipped with two beam diagnostic
devices whose positions can be changed by pneumatic
cylinder. Most of the elements have control interfacesthat are identical to those in BigRIPS and ZeroDegree spectrometer. Therefore, the control system waseasily modiﬁed by adding a new control record that isbased on the same control routine as those in BigRIPS
and ZeroDegree spectrometer. On the other hand, forthe control of the STQ, STQ-H19, a new control routine was required since the power supply of STQ-H19
uses the general purpose interface bus (GPIB) for thecontrol. The interface routine that issues and receives
GPIB commands to and from the power supply was
written by using the frame work of ”asyn-GPIB” utility in the EPICS. The routine was developed such that
STQ-H19 would have a same user interface as othermagnets.
The control logic of currents of the magnets was
modiﬁed in order to improve the operativeness. A
scaling factor was introduced into the calculation of
the currents. Originally, the currents of the magnets
were calculated using the central rigidity, the beam
optics parameters, and the excitation function of themagnets.1) The central rigidity was converted to thestrength magnetic ﬁelds of the magnets by using thebeam optics parameters, and then, the current wascalculated from the magnetic ﬁeld using the excitation function. In the new control logic, the strengthof the magnetic ﬁeld is multiplied by the scaling factor before calculating the current. The current of themagnets is currently ﬁne-tuned by changing the scaling factor instead of changing the current directly sothat the correction will remain in the same ratio even
if the central rigidities are changed. Futhermore, thecontrol system was modiﬁed such that it could detect
the current drifts of the magnets.
In order to process simple I/O signals, the routines
which handle IP Power 9212 (AVIOSYS InternationalInc.) and PICNIC (TriState Ltd.) were developedand included in the system. These devices are tinyboxes which control digital I/O through the Ethernet. PICNIC has the capability of the analog input
also. The device support routine sends the command
packet through Ethernet and receives response packets from them synchronously. The routine depends
only on the standard EPICS libraries and does not require any device-speciﬁc libraries. Device support for
Lock-In Ampliﬁer SR844 (Stanford Research systems),
which along with the fast current transformer is used
for obtaining the beam current was also provided insimilar manner. Data from the serial port (RS-232C)
of SR844 are converted to the Ethernet packets by theserial device server NPort 5410 (MOXA Inc.), and the
Ethernet packets are received by the support routine.
References
1) K. Yoshida et al.: RIKEN Accel. Prog. Rep. 41, 127(2008).
2) http://www.aps.anl.gov/epics/- 155 -

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Testing of Beam Viewer at BigRIPS
K. Yoshida, A. Yoshida, Y. Yanagisawa, T. Ohnishi, N. Fukuda, K. Kusaka, M. Ohtake, H. Takeda, D. Kameda,
N. Inabe, K. Tanaka, and T. Kubo
A beam viewer composed of a video camera and aﬂuorescent plate is one of the popular beam diagnostic
devices that evaluate beam characteristics such as the
position, shape, and size of the beam from an accelerator. When a beam impinges on the ﬂuorescent plate,the plate emits visible light which is detected by thevideo camera. The degree of lightening of the plate isa measure of the beam intensity. A vidicon camera ora charge coupled device (CCD) camera is commonlyused as the detection camera. The sensitivity of beam
viewers is rather low and hence, generally, only the proﬁle of the primary beam from the accelerator is visible
to the viewer. Recent enhancement of the sensitivityof CCD cameras, however, makes it possible to observe
the proﬁle of secondary beams which usually have very
low intensity.1)
The testing of the beam viewer was carried out in
the F2 chamber of BigRIPS using the primary andsecondary beams from SRC and BigRIPS. The detection camera used was an ultra high-sensitivity CCD
camera (WAT-902H2 Ultimate, WATEC, minimum illumination: 0.0001 lx at f-number: 1.4) coupled with
an LMVE-990A lens (KOWA, f-number: 1.8). Fluorescent plates made from three types of phosphors,
Y2 O2 S:Eu (NP1154-67RG, Nichia Corp.), ZnS:Cu, Al(NP-1108-110RG, Nichia Corp.), and Zn2 SiO4 :Mn(P1G1, Kasei Optonix) were examined. The camera
was set at the top of the F2 chamber and could record
the light emitted by the plate through the glass ﬂangeof the chamber. The ﬂuorescent plates were mounted
on the movable ladder of the F2 chamber. The plates
were positioned perpendicular to the direction of thebeam and the emitted light was observed in the direction of 60◦ relative to the beam direction. NTSC video
signal from the camera was sent to a video-capture
card of a computer.
The ﬂuorescent plates were irradiated by a 14 N beamwith an energy of 250 MeV/n and an intensity ofless than 500 kcps. The largest signal was obtained
from the plate made from Y2 O2 S:Eu phosphor among
the three phosphors tested. The plate made from
ZnS:Cu,Al phosphor gave a signal that was nearly thesame as that given by the plate made from Y2 O2 S:Eu
phosphor. The Zn2 SiO4 :Mn phosphor plate only gavea signal that was smaller than that of the Y2 O2 S:Eu
phosphor plate by a factor of 5 .
Figure 1 shows the obtained image of the Y2 O2 S:Eu
phosphor plate irradiated by the 14 N primary beamand 12 B secondary beam which was produced from the14
N beam. An oblong, white spot at the center of Fig.
1a represents the 14 N primary beam with an inten-

sity of 8 kcps. Small white dots scattered all over Fig.
1a are the noise from the ampliﬁer inside the WAT902H2. The noise can be eliminated by averaging acouple of images captured under the same conditions.
Fig. 1b shows the average of 30 images which corresponds to the average of video signals during 1s. The
noise is eliminated to a considerable extent, and thebeam shape is clearly seen. As seen in Fig. 1c, a beamwith an intensity as low as 1.5 kcps can be observedwith this method. The 12 B secondary beam with anintensity of 150 kcps can be observed. Since the secondary beam has a large emittance, its beam size ismuch larger than that of the primary beam; hence,higher intensity is needed to observe its shape in similar brightness.
During this testing, the averaging of the recorded
images was performed oﬀ-line. Therefore, we cannot
observe the clear picture on-line. In order to observe
the clear picture on-line, we are considering the use of a
special video-capture card that provides the averaging
function, or the use of a frame accumulation camerathat has a slow shutter speed such as 1s.
References
1) J. W. Stetson: Notes on NSCL Beam Viewplates,
NSCL, Michigan State University, private communication.

Fig. 1. Observed pictures of the beams. a) A 14 N primarybeam with an intensity of 8 kcps. b) A 14 N primarybeam with an intensity of 8 kcps (after averaging). c)
A 14 N primary beam with an intensity of 1.5 kcps (after
averaging). d) A 12 B secondary beam with an intensityof 150 kcps (after averaging).

- 156 -

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Measurement of field maps of superconducting quadrupole andsextupole magnets
H. Takeda, T. Kubo, T. Ohnishi, N. Fukuda, M. Matsushita,∗1 H. Sato, K. Kusaka, and Y. Yanagisawa
BigRIPS1) is an in-flight RI beam separator at
RIBF. Its operation is based on a two-stage separation
scheme; energetic RI beams are produced and separated in the first stage and particle identification is
performed in the second stage. The mass-to-charge
ratio A/Q is one of the most important quantities inparticle identifications because in the range of energies at RIBF, RI beams are produced in several charge
states, especially in the case of heavy RI beams. Large
acceptance is an important feature of BigRIPS that facilitates efficient transmission of RI beams even when
the in-flight fission of uranium beams is carried out as a
production reaction. Large-aperture superconducting
triplet-quadrupole (STQ) magnets are used to realize
large acceptance. Ion optical calculations with realistic magnetic field maps are necessary for achieving
high resolution in A/Q.
We have already measured the field maps of the
STQs at 20-A intervals of excitation currents from 20 A
to 165 A2) . However, we found that these maps may
not be satisfactory in the range of currents around
80 A, where the effective lengths vary on the order of
1% between the 20-A intervals used for measurement.
The measurement of sextupole magnets, which are superimposed on some quadrupole magnets, was also unsatisfactory. It is already known that the field maps ofthe sextupole magnet were affected by the excitationof the corresponding quadrupole magnet; however, themeasurements performed by exciting the quadrupole
magnet have been limited to a few combinations ofquad- and sextupole excitation currents. Thus, we alsomeasured the field maps of quadrupole and sextupole
magnets. Since STQ7, which has been used in theprevious measurement, was installed in the BigRIPS
beamline and was unavailable for the measurements,
STQ22 was used. Since STQ22 is located at the end of
the ZeroDegree spectrometer, a field-mapping device(Fig. 1) can be easily installed. The STQ22 consistsof Q500, Q800, and Q500, where the nominal effective
lengths of Q500 and Q800 are 500 mm and 800 mm, respectively. In the case of STQ22, the sextupole magnet
is superimposed on the upstream Q500 magnet.
We measured the cylindrical field maps (Br , Bθ , Bz )along the beam axis, where Br , Bθ , and Bz are the fieldcomponents along the radial, azimuthal, and beamaxes, respectively. Three-axis Hall sensors (AXIS-3
AERPOC Ltd.) were mounted on an arm of the mapping device, as shown in Fig. 2. The axes of the sensors
corresponded to the r, θ, and z directions describedabove. The center of the sensors was fixed on the arm∗1

Department of Physics, Rikkyo University

at radii r of 81, 94, and 107 mm from the beam axis.
The arm was moved with a two-motion stage driven
by stepping motors in the θ and z directions. The
measurement was performed at 10-mm intervals in thez direction. At each z position, the arm was rotated360◦ at steps of 3◦ when the sextupole magnet was excited. When quadrupole measurement was carried out
without exciting the sextupole magnet, 9◦ steps wereapplied to save measurement time. The Hall voltages
were measured by a digital multimeter (KEITHLEY
2700+7700) with a drive current of 10 mA supplied bya current source (Yokogawa 7651). Calibration data
for each Hall sensor were obtained by using an NMR
probe inside the SHARAQ D2 magnetic field in both
directions. A cubic spline was used for interpolation of
the calibration data. We also installed a thermocouple
device near the Hall sensors to measure the temperature drift. The drift was less than ±1 K throughout
the measurement. The quadrupole and sextupole components of the field were extracted from the measured
magnetic fields by applying a discrete Fourier trans-

Fig. 1. Field-mapping device (before installation inside the
STQ)

Fig. 2. Hall sensors are mounted on an arm of the fieldmapping device.

- 157 -

1

1.1

Q500

SX = -40 A
1.05

540

SX = -30 A
SX = -20 A

538

effective length (mm)

542

536

SX = +20 A

1

SX = +30 A
SX = +40 A

0.95

534
532
530

0.9

0.85

528
526
0

50

100

150

0.8

200

0

50

current (A)Fig. 3. Effective lengths of Q500

150

200

Fig. 6. The ratio of the field strength of the sextupole magnet at the magnet center under quadrupole excitation
to that in the absence of quadrupole excitation is plotted.

Q800
840
835
830

545

825

540



effective length (mm)100

820
815
810
0

50

100

150

200

current (A)Fig. 4. Effective lengths of Q800

535
530

SX = -40 A
SX = -30 A

525

SX = -20 A
SX = +20 A

520

SX = +30 A
SX = +40 A

515
0

50

100



150

200

Fig. 7. Effective lengths of the sextupole magnet.


50

0
-1000

-500

0

500

1000



-50

-100
20 A

-150

60 A
80 A
100 A

-200

120 A
140 A

-250

160 A



Fig. 5. Field maps of the sextupole magnet at −46A. The
corresponding quadrupole currents are changed.

formation. These distributions are implemented in the
COSY ion optical calculation. Octupole and higher
components are also obtained, but currently, they are
not taken into account in the COSY calculation.
In order to check the agreement with previous measurements, the effective lengths of Q500 and Q800 are
plotted as a function of excitation current in Figs. 3
and 4. We can see that the newly measured data (diamond marks) are consistent with previous data (crossmarks). An example of the sextupole magnetic field
distribution is shown in Fig. 5, where the sextupole
components of the magnetic field at a warm bore radius of 120 mm are plotted as a function of z position
along the beam axis. Note that the sign of the field is2- 158 -

defined such that particles with positive x-values are
driven toward or away from the optic axis under the
influence of a positive or negative field, respectively.
In this figure, the excitation current is fixed at −46 A
for the sextupole magnet, whereas the corresponding
quadrupole currents are changed. The field strengths
decrease as the current of the quadrupole increases.
The same features can be seen at all other sextupole
currents in Fig. 6, in which the ratio of the sextupole
field strength to the field strength in the absence of thequadrupole excitation at z = 0 (the center of the Q500
magnet) are plotted. The effective lengths of the sextupole magnet also vary according to the quadrupole
currents, as shown in Fig. 7. These features seem tobe related to the saturation of the magnet pole. Ion
optical analysis using newly measured field maps is inprogress.
References
1) T. Kubo: Nucl. Instr. and Meth. B204, 97 (2003).
2) Y. Yanagisawa et al.: RIKEN Acc. Prog. Rep. 41, 125(2008).

RIKEN Accel.
Accel. Prog.
RIKEN
Prog. Rep.
Rep.4343 (2010)(2010).

Radiation-shielding system between the high-power beam dump and thesecond superconducting quadrupole triplet in the first stage of BigRIPS
N. Inabe, K. Tanaka, K. Yoshida, M. Ohtake, N. Fukuda, D. Kameda, and T. Kubo

Production of RI beams using high-intensity (highpower) primary beams cause serious problems such asradiation damages, radiation heat loads, and high residual
radiation in the devices and components in the first stage of
the BigRIPS separator 1) where the production target andbeam dump are located. These problems arise because of
the strong flux of neutrons and light charged particles
emitted from the production target and beam dump, as wellas the intense primary beam itself. Figure 1 shows aschematic layout of the first stage that includes the
production target and the beam dump2).
The intense primary beam stops at the beam dump. The
target beam power is 83 kW, which is the same as that of a238
U beam at 345 MeV/u and 1 pA. The resulting highresidual radiation will prevent us from approaching avacuum beam duct between the beam dump and the second
superconducting quardulole triplet (STQ2). This vacuum
duct must be detached when maintenance work (orreplacement ) of the beam dump and the first dipole magnet(D1) that accommodates the beam-dump chamber isrequired. See Fig. 1 for details. Furthermore, the strong
flux of neutrons and light charged particles emitted from thebeam dump lead to heat loads and radiation damage of the
STQ2. In order to find a solution to these problems, wehave built and installed a radiation-shielding system in thesmall gap between the beam dump and STQ2.
Figure 2 shows a schematic drawing of the total system
which consists of 4 parts. A base part, a guide part and ashield part compose the radiation-shielding systemmanufactured by Toshiba Co. Ltd. A pillow seal part,manufactured by Mirapro Co. Ltd, is a vacuum duct whichenables to detach the vacuum connection by remotehandling. A detail description of the pillow seal ispresented elsewhere in this progress report 3).

Fig. 2. Schematic drawing of the total system (above) andits photograph taken in Toshiba factory (below)

Fig. 1. Schematic layout (top view) of the first stage ofBigRIPS around the production target and the beam dump.
The radiation-shielding system has been installed in small
gap between the beam dump chamber and STQ2.

- 159 -The radiation-shielding system was designed by taking
into account small clearances that are required between thedevices so that the devices can be safely removed on formaintenance work.
Oscillations occuring due toearthquakes were also taken into consideration in the design,
assuming horizontal acceleration of 0.45 g. The systemwas designed to have a robust structure so that theoscillation amplitude will be less than ±2.5 mm, which is
sufficiently small for the clearances.
The radiation-shielding system was mounted by placing
the base part on top of the walls on both sides of the
BigRIPS beam line, as shown in Fig. 2. The shield partwas inserted downward into the beam line along the guidepart, which is supported by the base part. The shield partwas safely inserted using guide rails called LM guides,
which are attached between the guide and the shield parts.
The pillow seal was positioned by adjusting the position of
the guide part. This adjustment was performed by using
adjustment blocks in the base part. The alignment
accuracy achieved was better than ± 1 mm.
Theradiation-shielding system including the base part must be
removed when the maintenance of D1, STQ2, and beam
dump is performed. Two knock pins are used in the base
part in order to ensure that the alignment remains the same
as before when the system is installed again.
The radiation-shielding system was constructed usingiron (SS400) and tungsten (W) alloy (AN-1800 by
Mitsubishi Material CMI Co. Ltd.). The total weight ofthe system was about 12.5 tons. The W alloy (heavy metal,
18.0 g/cm3) was used near the axis of the primary beams(see Fig. 2 below) where the flux of the neutrons is strong
because its shielding capability is about 1.5 times that ofiron. Water-cooling channels were provided on the surfaceof the W-alloy part to reduce the effect of the radiation heatloads. The W-alloy part was coated with a thin layer ofsprayed aluminum in order to ensure good heat transfer
between the W-alloy part and the water channels. The
thicknesses of the iron and the W-alloy parts are 100 mm
and 110 mm respectively.

The thickness of the new iron shield is 400 mm and its
radiation-shielding capability is comparable to that of theconcrete block of 1-m thickness. The upper iron plates
were painted with an organic Zn-rich paint (Galber#400FC) in order to increase the friction between concrete
blocks that are piled above them. The organic Zn-rich
paint is resistant to radiation. The total weight of the ironshield is about 52 t.
The radiation-shielding system was installed in the
middle of August 2009 and about one month was required
to complete the installation. Prior to the installation of theradiation shield by Toshiba, we removed the concrete
blocks of the ceiling and the beam duct between the
beam-dump chamber and STQ2 and attached mirror flanges
to the vacuum flanges of both the beam-dump chamber and
STQ2. The diaphragm of the pillow seal was made totouch the mirror flange to maintain the vacuum. The
removal of the beam duct and the mounting of the mirror
flanges were performed in a very narrow space and underrelatively high residual radiation. Therefore, prior to theactual removal and mounting, these actions were performed
many times using a mock-up that simulated the system3).
After the installation, we carried out a vacuum test to
confirm that vacuum was maintained well by the pillow seal.
Finally, we replaced the concrete blocks with the new ironshield. All work related to the installation of theradiation-shielding system was completed by the middle of
October.

Fig. 4. Schematic drawing of the new iron shield. The
black arrow points to the side shown in Fig. 3
Fig. 3.
Side view of theradiation-shielding system is installed.

area

where

the

Figure 3 shows the side view of the area where theradiation-shielding system is installed. In order to install
the radiation-shielding system, a concrete block of 1-m
thickness, which was used to shield the ceiling of the firststage of BigRIPS4) was replaced with a new iron shield. A
schematic drawing of the iron shield is shown in Fig. 4.
The iron shield was produced by OES Aqua Fuoco Co. Ltd.

References
1) T. Kubo: Nucl. Instr. Meth. B 204, 97 (2003).

2) N. Fukuda et al. RIKEN Accel. Prog. Rep. 41, 119 (2008).
3) K. Tanaka et al. in this progress report
4) K. Yoshida et al. RIKEN Accel. Prog. Rep. 37, 301 (2004).

- 160 -

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Pillow seal around the beam dump of the BigRIPS
K. Tanaka, N. Inabe, N. Fukuda, D. Kameda, M. Ohtake, K. Yoshida, and T. Kubo
A pillow seal is a remotely operated vacuum ductutilized in high-radiation environments. The pillowseal system was invented at the Paul Scherrer Instituteand then improved by the High-Energy Accelerator
Research Organization (KEK) hadron group1) . Highintensity primary beams cause a high neutron flux inthe devices around the beam dump of the BigRIPS
separator in the RI beam factory (RIBF)2) , thus causing high-radiation damage and residual radiation. Thishigh residual radiation prevents us from approaching
the devices around the beam dump that are in needof replacement or maintenance work. In order to overcome this problem, a pillow-seal system was installed
to connect the chamber of the fist room-temperature
dipole (D1), which contains the beam dump, andthe second superconducting triplet quadrupole magnet(STQ2) of the BigRIPS.
The pillow seal is remotely operated using compressed air in order to reduce personal exposure toresidual radiation. Figure 1 shows the structure of a

Fig. 1. Schematic view of a pillow seal. Three pipes areconnected to the pillow-seal flanges. Two pipes are forcompressed air and another is for vacuum. See text for
details.

pillow seal. The pillow seal consists of two flanges connected by dual bellows. The length of the pillow seal
is decreased by evacuating the dual bellows and is increased by using compressed air.
Vacuum sealing is achieved using the pillow seal asfollows: The seal surface is in contact with the special flange (seal-face flange), which faces the pillow seal
once the bellows are extended. Diaphragms that can
expand are utilized to remain in contact with the surface of the seal-face flanges. Compressed air is filledin the region between the flange and diaphragms to
expand the diaphragm, as shown in the sectional sideview in Fig. 1. The diaphragm surfaces are polishedto obtain a mirror-like finish within 5-nm roughness tomake the vacuum seals. The surfaces of the seal-faceflanges are also polished to obtain a mirror-like finish.
The mirror-like surface of the diaphragms get tightly
stretched over the seal-face flange by extended bellowsof the pillow seal. As a result, vacuum sealing of themetal surfaces in close contact is achieved without employing any radiation-sensitive gaskets, such as rubber
O-rings. The reverse procedure is followed to detachthe pillow seal. As shown in Fig. 1, the seal surfaces
have a double structure. The intermediate region between two seal surfaces is vacuated to improve the seal
performance1) .
Figure 2 shows the RIBF pillow-seal system. The
RIBF pillow seal is present inside the radiation shield;
the latter is also required in the narrow space between
D1 and STQ23) . Three bearings on the side of thepillow-seal flanges remain in contact with the innershield, as indicated in Fig. 2, in order to align thepillow seal. The bearings move the pillow-seal flanges
smoothly along the beam axis to extend or shorten
the pillow seal. The space where the RIBF pillow seal
will be installed has a length of 100 mm, and the inner shield is 90-mm thick. In order to be mounted,
the RIBF pillow seal is shortened to a length of 80
mm. The outer shield has guides to mount and dismount the RIBF pillow seal system. Two pivots andguides on the outer shield are used to align the innershield with the pillow seal. The pillow seal in the innershield is positioned within ±1 mm relative to the center of the outer shield. The inner shield is made of analloy of stainless steel, lead, and tungsten alloy (A1800
produced by Mitsubishi Material CMI Co. Ltd.). The
tungsten alloy has 1.5 times better shielding capability
than an alloy of stainless steel and lead. Therefore, it
can be located near the pillow seal where the neutron
flux is high. In order to reduce the radiation-heat loadon the pillow seal, colling water can be circulated in
the channels within the flanges. 0.3-MPa N2 gas is- 161 -

1

quickly and precisely. As a result, the time requiredfor completing the installation process reduced by half,
and the exposure was limited to less than 15 µSv in a
∼100-µSv/h environment4) .
The radiation shield along with the RIBF pillow-seal
system was installed after the seal-face flanges were
installed, and then the pillow seal was connected to
the BigRIPS setup. The leak rate was found to be over
10−9 Pa m3 s−1 which is appropriate for the vacuum inthe BigRIPS setups.

Fig. 2. Schematic view of the pillow seal mounted on theradiation shield. The pillow seal with three bearings ispresent in the inner shield. The inner shield is mounted
in the guide on the outer shield with bearings attachedon the inner shield. Unlike the pillow seal shown in
Fig. 1, two pipes for cooling water are connected to thepillow-seal flange.

used to operate the pillow seal instead of compressed
air because NOx corrosion as a result of air (N2 + O2 )activation is possible when air is used.
We developed a test bench to check the vacuumsealing performance of the pillow seal before we design
the pillow-seal system along with the radiation shield.
Figure 3 schematically shows the test bench. The position and slope of the pillow seal with respect to the twoseal-face flanges can be changed, and the leak rate wasmeasured using helium under several conditions. The
leak rate was lower than 10−9 Pa m3 s−1 for a ±2-mm
difference in the position and a ±10-mrad difference in
the inclination of the pillow-seal flanges relative to theseal-face flange.
The detachment of an existing duct and the attachment of the two seal-face flanges will have to be carriedout in a narrow space in the high-residual-radiation
environment before installing the pillow-seal system inthe BigRIPS. Radiation-hard metal O-rings (U-tightseal produced by Usui Kokusai Sangyo Co. Ltd.) wereused as gaskets for the two seal-face flanges, where ahigh neutron flux is provided from the beam dump.
To reduce the radiation exposure as much as possible, mock-ups of D1 magnet, D1 chamber, and STQ2
magnet were built to improve the installation process and to practice completing the installation more2

- 162 -

Fig. 3. Schematic view of the test bench. The pillow-seal
system is mounted in the guide, as shown in this figure,which is similar to that of the outer shield shown in
Fig. 2. To test the effects of any alignment changes,
the the pillow seal in the guide can be shifted along thehorizontal (X) and vertical (Y) direction. The seal-faceflanges can shift along the beam-axis direction (Z) withthe base flanges, and they can be declined using theshim between the support and base flanges.

----References
1) Y. Yamanoi et al.: Proc. 2nd Annual Meeting of Particle
Accelerator Society of Japan and the 30th Linear Accelerator Meeting in Japan, Tosu, Japan, 2005-6, p. 736.
2) T.Kubo: Nucl. Instr. and Meth. B 204, 97 (2003).
3) N. Inabe et al.: in this report.
4) K. Tanaka et al.: in this report.

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Radiation measurement around the BigRIPS
K. Tanaka, N. Inabe, Y. Gono, and T. Kubo
䡾䎃F0 Chamber䡿䎃D1 front48
4
Ca 10 pnA
䢀䎃Beam-Dump Chamber
108䎃
α 300 pnA
6 48
Ca 100 pnA

D o se ra te ( µS v/h )

2

4

2

setup change
3{

Since the setup around the BigRIPS is being continuously modified and improved, it is necessary to predict the residual radioactivity in the region by taking
into account the beam intensity and the beam coolingtime in order to reduce exposure to residual radiation.
Since the installation of a pillow-seal system aroundthe beam dump of the BigRIPS where the radiationlevel was high was planned in the summer of 2009, aprecise estimation of the radiation dose was necessary.
Therefore, we measured the residual radioactivity atseveral places around the BigRIPS by using the Teletector 6112D GM survey meter, which can perform
remote measurements, and we evaluated their time dependence. A γ-ray spectrum was also measured in theregion of the beam dump with a Ge detector in order
to identify the residual radionuclides and to predict
future dose rates.

10

8
6
4

2
2

10

8
6

2009/01/01

2009/05/01

2009/09/01

2010/01/01

Day

Fig. 2. Time dependence of the residual radioactivity.
Spots of each plot are shown in Fig. 1. Owing to intense beams indicated in this figure, the radioactivities
highly rose.

1

occurred as a result of the setup changes and beamirradiations, as indicated in the figure. From June to
October 2009, the setup around the F0 production target and the beam-dump chamber were changed. In
particular, the F0 chamber was replaced with a newone1) in June 2009, and then the dose rate decreased
considerably.

F0

2

STQ1

1

100103
D1

4

80
Count

3

2
60

3

5

5

5

40

Beam-dump chamber

8511 keV

8

7

20

6 7

6

0
0

STQ2

F1

Fig. 1. Layout around the F0 and the beam-dump chamberof the BigRIPS.

The spots 1–3, which have been marked with solid
circles in Fig. 1, denote the places around BigRIPS
where high dose rates were observed. Figure 2 shows
the time dependence of the measured radioactivity.
Some unnatural variations in the plots shown in Fig. 2

500

1000
Energy (KeV)

1500

2000

Fig. 3. Ge spectrum measured around the beam-dump
chamber. The numbers in this figure indicate the nuclides listed in Table 1. Peaks with same numbers indicate the same nuclide.

In August 2009, the setup around the beam-dump
chamber where the radiation was already high waschanged2) . In order to precisely estimate the personal
exposure during this work, and to prepare an efficient
work plan, we measured a γ-ray spectrum (Fig. 3) near
the beam-dump chamber with a Ge detector on March
2, 2009. The major material in the setup used around- 163 -

1

Table 1. List of the nuclides and their properties measured using a Ge detector placed near the beamdump chamber. Peak Nos. 1–8 indicate the peaks shown in Fig. 3, which were measured on March
2, 2009. The nuclides that mainly contributed to the radiation are listed in the table. The radiation
due to the nuclides that was estimated in August 2009 is also listed.
Peak No.

1
2
3
4
5
6
7
8

Nuclide

57

Co
Mn
58
Co
54
Mn
56
Co

51

46

Sc
V
60
Co
48

Energy (keV)

122
320
811
835
846, 1037, 1238,
1772, 2598
889
984, 1037, 1312
1173, 1332

Half life

271 days
28 days
71 days
312 days
79 days

Dose ratio (%)
March 2009
(measured)
0.3
1.5
25
27
17

84 days
16 days
5.3 years

7.8
8.1
11

5.0
0.01
26

98
Radioactivity (µSv/h)
230

100

total

the beam-dump chamber is stainless steel (SUS316).
From the spectrum, we identified the nuclides thatmainly contribute to the radiation dose near the beamdump chamber; they were 54 Mn, 56 Co, 58 Co, and 60 Co.
The radiation dose in August was estimated by taking
into account the half lives of the nuclides. Table 1
shows the observed major nuclides and their radioactivity. In this table, the dose was relatively estimatedusing the photoelectric-peak count of the spectrum,
the correction factor for the detector efficiency (²), andthe γ-ray energy, as
dose ∝ (peak count)/² × energy.

(1)

The dose ratio is the ratio of each nuclide dose to thesum of all nuclide doses. In August 2009, the dose ratios were estimated from the ratios obtained on March
2, 2009 by taking into account the half lives of thenuclides. The total dose was measured with the GM
survey meter on March 2 and August 20 at the spot
where the setup was changed2) . As shown in Table 1,
the radiation doses estimated in August were accurate
within ± 10 %.
References
1) A. Yoshida et al.: In this report.
2) K. Tanaka et al.: In this report.

- 164 -⇒⇒

August 2009
(estimated)
0.5
0.06
12
47
10

90 (estimated)
85 (measured)RIKEN Accel. Prog. Rep. 43 (2010)

Separation of RI beams using two-stage separation method in
BigRIPS
N. Fukuda, T. Kubo, T. Ohnishi, N. Inabe, H. Takeda, D. Kameda,
and ZeroDegree commissioning collaboration[In-ﬂight ﬁssion, Particle identiﬁcation]
One of the important characteristics of the BigRIPS
in-ﬂight separator1) is its two-stage structure (Fig. 1).
The two-stage structure can be used for the deliveryof tagged RI beams or as two separators in tandemwith each other. The former is achieved in the tagging mode of the separator1) in which the ﬁrst stage isused to produce and separate RI beams with a wedgeshaped degrader, while the second stage works as aspectrometer to analyze and identify those RI beams.
The latter is achieved in the two-stage separation modeof the separator, where an additional energy degraderis used at the second stage to further purify the RI
beams.
In the commissioning experiment of the ZeroDegree
spectrometer conducted in November 2008, we tested
the applicability of the two-stage isotope-separation
method in separating the ﬁssion fragments produced in
the 238 U+Pb reaction at 345 MeV/nucleon. The produced ﬁssion fragments have momentum spread over alarge range; this is a characteristic of Uranium ﬁssion.
Consequently, we detected more than 200 diﬀerent isotopes having the same magnetic rigidity.
In this report, we present the experimental results
and demonstrate the applicability of the two-stage separation method in the BigRIPS separator.
In the above experiment, a 238 U86+ beam bombarded a Pb target having a thickness of 1.5 mm at
E = 345 MeV/nucleon. The magnetic rigidity (Bρ)
of the ﬁrst dipole magnet (D1) was set to 7.3940 Tm,
which was kept constant during the measurement. The
momentum slit was set to ±3% by suitably adjustingslits at the F1 dispersive focus located at the center ofthe ﬁrst stage (F0–F2). In the two-stage separation
method, the ﬁrst wedge-shaped aluminum degrader
having a thickness of 3 mm was installed at the F1
focal plane in the ﬁrst stage, and the second curved
aluminum degrader having a thickness of 1.8 mm wasinstalled at the F5 dispersive focus located at the center of the second stage (F3–F7). The Bρ values in
the region following the F1 were set so as to obtain
140
Te52+ at the center of each focal plane and collectthe isotopes with atomic numbers Z in the range of
50–55. The slit at F2 was set to ±15 mm.
The second stage is designed to function as a spectrometer for particle identiﬁcation (PID). The PID was
performed by measuring the energy loss (∆E), time of
ﬂight (TOF), and Bρ of the fragments using the beamline detectors installed at the F3, F5, and F7 foci. The∆E was measured at F7, while the TOF measurement
was performed between F3 and F7. The Bρ was determined by tracking the trajectories of the fragments between F3 and F5, and those between F5 and F7. Since
we use the Bρ between F3 and F5 (Bρ35 ) or the one
between F5 and F7 (Bρ57 ) for PID, we have to know
the velocity between F3 and F5 (β35 c) or between F5and F7 (β57 c). If the mass-to-charge ratio (A/Q) does
not change at the F5 degrader, the β35 value can be
deduced from the following relations:(A/Q)35 γ35 β35
Bρ35
=
,
Bρ57
(A/Q)57 γ57 β57
TOF37 =

L57
L35
+
,
β35 c β57 c

(1)
(2)

where γ, L, and u denote Lorentz factor, the ﬂightpath length, and atomic mass unit, respectively. In thedata analysis, we reject the events whose A/Q changes
at the F5 degrader by checking the correlation between
the Bρ35 and Bρ57 values.
The experimental results are shown in Fig. 2, where
the PID plots for three diﬀerent cases were obtained by
calculating the atomic number Z and the A/Q of eachfragment from the measured ∆E, TOF, and Bρ values.
In Fig. 2 (a) (the PID plot obtained when no degraderis used) more than 200 isotopes with Z ranging from30 to 55 are clearly indentiﬁed. In order to collect
the required isotopes with Z = 50–55, the energy degrader was installed at F1. Figure 2 (b) shows the PID
plot when the degrader is intalled. The relative yieldof the required isotopes increases up to approximately
40%, although some lighter isotopes (Z = 30–45) thatare contaminants may also be obtained. The contaminants are the isotopes that have diﬀerent atomic charge
state (H-like) between the F0 and the F1 degrader andFig. 1. Schematic layout of the BigRIPS separator. There
are seven foci in the beamline that are denoted as F1–
F7. The ﬁrst stage includes the components from theproduction target-position (F0) to F2, while the second
stage includes those from F3 to F7.

- 165 -

10

10

2

10

1

10

10

2

10

3

40
30

F3x (mm)these are transported to the F2 focus as fully electronstripped ions. The present identiﬁcation of the variations in the charge state is conﬁrmed by the position
distribution at F3 in which the charge dispersion can
be clearly seen as shown in Fig. 3.
In order to further purify the RI beams, anotherdegrader was installed at F5. The PID plot obtainedin this case is shown in Fig. 2 (c). The second degrader
ensures a drastic puriﬁcation of isotopes with Z = 50–
55 by rejecting the lighter ions. The purity achieved isover 99%.
Finally, we describe another beneﬁt of the two-stage
separation method. The use of the second degrader
reduces the amount of ions that are not completely
stripped, as shown in Fig. 4. The ﬁgure represents
the A/Q spectra of Sn (Z = 50) isotopes for the cases(a) without degrader, (b) with one degrader, and (c)with two degraders. The relative yield of 132 Sn49+ to135
Sn50+ in the case of two-stage separation is negligible compared to those in the cases when no degraderor one degrader is used.

QD1 = QD2

20
10
0
−10
−20

QD1 = QD2 - 1

−30
−40
20

30

40

Z

50

60

Fig. 3. Two-dimensional plot of the x-position at F3 (F 3x)
versus Z showing charge dispersion at the F3 focus.
Two components of charge dispersion are seen. The
isotopes with Z = 50–55 are transported from F0 to F3
as fully stripped ions, while those with Z = 30–45 aretransported from F0 to the F1 degrader as H-like ions,then are transported from F1 to F3 as fully stripped
ions.

3

60
50
40
30

Counts

20
60

Z

50
40
30
20
60

A/Q

50
40

Fig. 4. A/Q spectra of the Sn (Z = 50) isotopes obtained
for the cases (a) without degrader, (b) with one degrader (F1), and (c) with two degraders (F1 and F5).
135
Sn50+ and its contaminant 132 Sn49+ are indicated byarrows. The ratio of 132 Sn49+ to 135 Sn50+ for the twostage separation case is negligible compared to those forthe cases when no degrader or one degrader is used.

30
20
2.4

2.5

2.6

2.7

2.8

A/Q

Fig. 2. Two-dimensional plots of Z versus A/Q for the ﬁssion fragments produced in the 238 U+Pb reaction obtained (a) without degrader, (b) with one degrader (F1)
setup, and (c) with two degrader (F1 and F5) setup.

2- 166 -

References
1) T. Kubo: Nucl. Instr. and Meth. B 204, 97 (2003).

RIKEN Accel. Prog. Rep. 43 (2010)

CCJ Operation in 2008-2009
T. Nakamura, H. En’yo, Y. Goto, T. Ichihara, Y. Watanabe and S. Yokkaichi
Overview
The RIKEN Computing Center in Japan (CCJ)1)
has been developed since April 1998 for analyzing thehuge amounts of data collected in the PHENIX experiment at RHIC. Thus far, CCJ has been providing
numerous services as Asia’s regional computing center. For instance, CCJ maintains sufficient computing power by the PC cluster operated by ScientificLinux2) for simulation and individual data analysis.
The collected data are transferred through SINET3
with a 10 Gbps bandwidth, maintained by NII3) ,from Brookheaven National Laboratory (BNL) by using GridFTP4) . The transferred data are once stored
in High Performance Storage System (HPSS)5) before starting the analysis. This HPSS is one of thejoint operations with the RIKEN Integrated Clusterof Clusters (RICC) project. One of the most successful achievements of the CCJ operation up to now is
the completion of more than 30 doctoral dissertations
with the analysis results obtained using the computing
resources at CCJ.
A summary of the basic configuration of the CCJ
system has been published elsewhere6) . Since last year,
several major hardware-level upgrades have been carried out. The center network switch has been replacedwith Catalyst4900M, which has eight 10 Gbps ports, inJuly 2009. The operation of the HPSS was started witha new version 7.1 in January 2010. In February 2010,
four sets of UPS were replaced by SANUPS ADS series (Sanyo Denki). The server (ccjnfs11) for Network
File system (NFS), which managed a 6.8 TB FC-FC
RAID box and a 8.9 TB FC-SATA RAID box, wasended the service to be upgraded in March 2010. Recently, effective use of the existing computing resources
has become difficult owing to the rapid increase in the
PHENIX data size. In this report, the details of several
upgrades and developments made to the CCJ systemin the 2008-2009 period are included.
2 PC cluster specification
Until early 2008, CCJ was operated by approximately 190 PC nodes, 166 nodes of which were used
as calculation nodes for the simulation and PHENIX
data analysis. In June 2008, 112 nodes were eliminated. The remaining 36 and 18 dual CPU nodes haveIntel Pentium III (1.4 GHz) CPU and Intel Pentium 4(2.0 GHz) CPU, respectively. Each calculation node
has 1 GB memories.
In February 2009, 18 PC nodes (HP ProLiant DL180
G5) were newly introduced to compensate for the low
total computing power. Each node has dual CPUs
(Quad-Core Intel Xeon E5430 2.66 GHz) and 16 GB
memories. These nodes have twelve 3.5 inch bays of

Total speed [MB/s]

1

600
500
400

1 disk8 parallel disks
RAID5 (HW)RAID5 (SW)

300
200
100
0
0

1

2

3

4

5

6
7
8
9
Number of parallel jobs

Fig. 1. Average total speed for reading 1 GB files in one
disk (square), 8 parallel disks (filled circle), hardware
RAID5 (open circle), and software RAID5 (triangle) as
a function of number of parallel jobs.

HDD for each chassis. Two 146 GB SAS disks aremounted for the operating system and used by mirroring to reduce the down time originating from the troubles on the HDD. Initially, eight 1 TB SATA disks were
mounted for local data storage. In December 2009, two
additional 1 TB SATA disks were added to each node.
Currently, local disks with a total capacity of 180 TB
are available for the data storage. This specificationis the key feature for I/O bound jobs, as will be described in the next section. Each node has a 1 Gbps
network interface card, and all of the nodes are connected to a network switch (Dell PowerConnect 6224)
mounted on the same rack. This network switch is up
linked to the center network switch at CCJ (Catalyst
4900M) via a 10 Gbps connection. This new cluster
has the capability to process a typical PHENIX analysis job approximately three times faster than the old
PC nodes in a CPU core.
In October 2009, 20 PC nodes were setup as a cluster
at RICC for the exclusive use of the CCJ users. Eachnode has dual CPUs (Quad-Core Intel Xeon X5570
2.93 GHz) and 12 GB memories and is operated by
Scientific Linux 4.4 on VMware ESXi7) so that it isdedicate to the PHENIX analysis environment. Condor8) system is available as a batch job scheduler forthis cluster.
Thus, a total of 412 CPU cores are presently available as calculation nodes for the CCJ users.
3 Development of job submission scheme
The PHENIX data stored once in the HPSS will betransferred to several RAID boxes for the analysis. Although users can access the data in the RAID boxes
through the NFS servers, multiple access from numer-- 167 -

Table 1. Summary of nDSTs in local disk.
DatasetRun 9 p + p 200 GeV
Run 9 p + p 500 GeV
Run 8 p + p 200 GeV
Run 6 p + p 200 GeV
Run 5 p + p 200 GeV

nDST type
All type
All type
All type
w/o detector
w/o detector

Data amount
65.4 TB
31.2 TB
21.2 TB
14.6 TB
9.9 TBous calculation nodes at the same time is not possible
because of the decrease in the I/O speed. Therefore,
users must transfer the data from the RAID boxes tothe calculation node for each batch job. Since the sizeof PHENIX data is growing steadily, such data transfer
becomes a bottleneck in data analysis. This problem iseliminated with the use of the newly introduced calculating nodes, which have large capacity local disks forstoring the data a priori (see previous section). However, since these new calculating nodes have multi-core
CPUs, which is predominant in the market, data analysis remains an I/O bound type job. Therefore, itis necessary to optimize the composition of the local
HDD. We performed a benchmark test to evaluate theI/O performance for the new cluster. Figure 1 shows
the average total speed for reading 1 GB files as a function of the number of parallel jobs. Originally, each
HDD shows the I/O performance of 100 MB/s. However, the use of a multi-HDD is not advantageous with
the RAID configuration, as shown by the open circles
and triangles in Fig. 1. Since the RAID configuration
gives us a single name space, maintaining the data location becomes easy. Nevertheless, we do not chose
this configuration to maximize the I/O performance.
In October 2009, approximately 96 TB Run 9 p + p
data, so-called nano-DST, were transferred from BNL
as soon as data reconstruction was completed at the
RHIC Computing Facility (RCF)9) . They were stored
in local disks along with the previously stored data.
Table 1 shows a summary of the dataset in the local
disks accessible to users by the batch queuing system.
In the calculation nodes, users can process their own
analysis code via the batch queuing system (LSF version 7.010) ) in the CCJ cluster. We have added some
software modules to enable the user specify the nDSTs distributed to the local disks during job submission. Figure 2 shows a brief flowchart of the dataoriented job submission scheme. Since all the subsetsof the PHENIX data have identical run numbers, themodule first obtains the location of the nDST by theuser-specified run number from a database. Then, themodule submits the user jobs to the appropriate nodeby the LSF. To avoid multiple access for a local disk
from several jobs, the module sets a lock file for exclusive access and grants permission only to the user by
the Access Control List (ACL) method. As a result,each job dispatched to a calculating node exclusively
handles a local disk. The advantage of this method
is that the I/O performance is enhanced, as shown by- 168 -

Fig. 2. Data-oriented job submission scheme.

the filled circles in Fig. 1. Further, a temporary work
area for the job is assigned to the same disk with thedata location. Therefore, this scheme is effective for
eliminating the I/O bound problem in case of genericjobs as well e.g. simulation. Each job are able to savethe processing time on the data transfer approximately
10 times as compared to the typical jobs in the preexisting calculating nodes. An instruction is provided inthis URL11) on how to access to the data stored in thelocal disks.
4 Summary
18 calculating nodes with 180 TB local disks wereintroduced for effectively analyzing huge amounts of
PHENIX data. A data-oriented batch queuing system
was developed as a wrapper of the LSF system to increase the total computing throughput. Indeed, thetotal throughput was improved by roughly 10 times ascompared to that in the existing clusters; CPU power
and I/O performance are increased threefold and tenfold, respectively. Thus, users can analyze data of several tens of terabytes within a few hours. This is oneof the most significant developments made to the CCJ
operation in 2009.
References
1) http://ccjsun.riken.jp/ccj/
2) http://www.scientificlinux.org/
3) http://www.nii.ac.jp/
4) http://www.globus.org/grid software/data/
gridftp.php5) http://www.hpss-collaboration.org/
6) S. Yokkaichi et al., RIKEN APR 42, 223 (2009).
7) http://www.vmware.com/products/esxi/8) http://www.cs.wisc.edu/condor/description.html
9) http://www.rhic.bnl.gov/RCF/
10) http://www.platform.com/products/LSF/11) http://ccjsun.riken.go.jp/ccj/doc/LSF/
lsf-wrapper. html

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

SHARAQ Project: Progress in 2009
T. Uesaka,∗1 S. Michimasa,∗1 S. Ota,∗1 A. Saito,∗1 K. Nakanishi,∗1 Y. Sasamoto,∗1 H. Miya,∗1 H. Tokieda,∗1
S. Kawase,∗1 Y. Shimizu,∗1 S. Shimoura,∗1 K. Miki,∗2 S. Noji,∗2 H. Sakai,∗2 K. Yako,∗2 S. Itoh,∗2 H. Kurei,∗1
N. Yamazaki,∗1 A. Yoshino,∗1 T. Kawabata,∗4 Y. Yanagisawa,∗3 T. Kubo,∗3 T. Ohnishi,∗3 H. Takeda,∗3
D. Kameda,∗3 N. Fukuda,∗3 K. Tanaka,∗3 K. Yoshida,∗3 A. Yoshida,∗3 N. Inabe,∗3 K. Kusaka,∗3 M. Ohtake,∗3
M. Kurokawa,∗3 M. Sasano,∗3 K. Itahashi,∗3 H. Baba,∗3 T. Ichihara,∗3 Y. Shimbara,∗5 M. Nagashima,∗5
G. P. A. Berg,∗6 D. Bazin,∗7 and P. Roussel-Chomaz,∗8
On March 23, 2009, the ﬁrst beam was successfullytransported to the ﬁnal focal plane of the SHARAQ
spectrometer. We investigated detector responses toheavy-ion beams and the ion optical properties of
the SHARAQ spectrometer1) and the high-resolution
beam line2) in the subsequent commissioning runs andfound that the system as a whole worked almost as per
its design. The ﬁrst physics run with the spectrometer
was performed in November 2009. In this article, we
review the progress in the SHARAQ project in 2009.
1

Last minutes of the construction

The construction of the spectrometer and the beamline was continued until the end of February 2009.
Cathode read-out drift chambers (CRDC) were installed at the focal plane of the SHARAQ spectrometerin January 2009. The vacuum chambers and pumping
systems of the spectrometer were built in February.

Fig. 1. Newly constructed beam line magnets: two normalconducting dipole magnets (DH7 and DH8) and a superconducting triplet quadrupole magnet(STQ-H15).

Two normal conducting dipole magnets with a bending angle of 30◦ , vacuum chambers for beam line de∗1

∗2
∗3
∗4
∗5
∗6
∗7
∗8

Center for Nuclear Study (CNS), University of Tokyo
Department of Physics, University of Tokyo
RIKEN Nishina Center
Kyoto University
Niigata University
University of Notre Dame
National Superconducting Cyclotron Laboratory, Michigan
State University
GANIL

tectors, and vacuum pumps were installed in the highresolution beam line in February 20093) . Figure 1
shows a photograph of the newly constructed beamline magnets: two normal-conducting dipole magnets (DH7 and DH8) and a superconducting triplet
quadrupole magnet(STQ-H15).
2

Commissioning runs

A primary 14 N beam accelerated up to 250 MeV in
SRC was transported from F0 of BigRIPS to the focal
plane of the SHARAQ spectrometer. This is the ﬁrst
time that a beam was accelerated without involving an
IRC. The ion beam struck plastic scintillation counters
placed downstream of the focal plane for the ﬁrst timeat 22:37 on March 23, 2009 (JST).
The beam-line detectors consisting of eight multiwire drift chambers (MWDC) and the SHARAQ focalplane CRDCs were irradiated by the 14 N beam andthe secondary beams of 12 B, 9 Li, 6 He, and 3 H at
200A MeV. The detectors were operated at a low gaspressure of 10 kPa for the beam-line MWDCs and at
2 kPa for the CRDCs. Detection eﬃciencies were foundto be almost 100% even for light ions with Z in therage 1–76,7) . We have also conﬁrmed that position resolutions are high and amount to 200–300 µm FWHM,
which meets the design requirements. A new data taking system was also found to function satisfactorily.
The ion-optical properties of the magnetic systemwere investigated by using beam trajectories determined by the tracking detectors described above. Momentum dispersions (x|δ) at the dispersive focal planes
F6 and FH7 and at the focal plane of the SHARAQ
spectrometer were found to be 7.8 m, 7.5 m and 5.8 m,
respectively. These values are consistent with the design values.
Beam-line tuning was carried out to achieve lateraland angular dispersion matching conditions and double focus conditions at the SHARAQ target position4) ;the tuning was performed by adjusting the excitation
currents of the four quadrupoles QH18, STQH19a, b,
and c. During the tuning, the correlations between
particle trajectories at the dispersive focal plane FH7
and at the focal plane of the SHARAQ spectometer
were used for diagnostics. The beam position at FH7,
xFH7 , corresponds to the beam momentum, and thus,
the correlation between xFH7 and the position in the- 169 -

1

focal plane of the SHARAQ spectrometer, xFP , provides a good measure of (x|δ) of the whole ion-opticalsystem. The upper panel of Fig. 2 shows the correlation between xFH7 and xFP . The upright correlation
between xFH7 and xFP in the ﬁgure clearly shows thatthe beam position at the focal plane of the SHARAQ
spectrometer is independent of the beam momentum,
which indicates the achievement of the lateral dispersion matching condition.

The resulting momentum resolution δp/p was foundto be approximately 8100. Further studies to improve the momentum resolution are in progress. Fromthe ion-optical studies, it is clearly demonstrated thattracking of the beam particles in the beam line facilitates beam line tuning that is required to obtain thedispersion matching conditions.
300

250

40

200

30

150

xFH7 [mm]

20

100

10

δp/p

0
-10

50

0.2%

0
2250

-20

2000

-30
-40

1750
1500

-20

0

May/09dispersion
matched !

1250

20

p/δp= 8100

1000

xFP [mm]

750

40

500
250

30

0
−40

20

xFH7 [mm]Achromatictransport

− 30

−20

−10

0

10

20

30

40

Position at Focal Plane [mm]10Fig. 3. Horizontal beam images at the ﬁnal focal plane in
the achromatic transport mode (upper panel) and in
the dispersion matched transport mode (lower panel).

0
-10
-20
-30
-40

3
-20

0

20

aFP [mrad]Fig. 2. Horizontal beam images at the ﬁnal focal plane in
the achromatic (upper panel) and the dispersion matching transport (lower panel).

Similarly, the correlation between xFH7 and the horizontal angle at the focal plane of the SHARAQ spectrometer, aFP , that is shown in the lower panel of Fig. 2
is a good measure of the angular dispersion matching.
After tuning, we succeeded in obtaining the lateraland angular dispersion matching conditions simultaneously.
Figure 3 shows the horizontal beam image at the
focal plane of the SHARAQ spectrometer. Its widthcorresponds to the intrinsic momentum resolution of
the ion-optical system. The upper panel presents thedata obtained in the achromatic transport mode. In
this mode, the resolution was limited by the momentum spread of the beam. After the dispersion matchingcondition was obtained by carrying out beam line tuning, the beam image was narrowed down considerably,
as shown in the lower panel of Fig. 3.

2

The (t, 3 He) Experiment- 170 -

The ﬁrst physics run with the SHARAQ spectrometer was performed to search for β + -type isovector spinmonopole resonances in 90 Zr and 208 Pb. The (t, 3 He)
reaction at 300 MeV/nucleon was used to extract β +strengths. An intense triton beam of 107 s−1 was produced by projectile fragmentation of a primary 320MeV/nucleon 4 He beam, and the scattered 3 He ionswere momentum-analyzed by the SHARAQ spectrometer. The details of the experiment are described inRef. 8.
References
1) T. Uesaka et al.: Nucl. Instrum. Methods B 266, 4218
(2008).
2) T. Kawabata et al.: Nucl. Instrum. Methods B 266,
4201 (2008).
3) Y. Yanagisawa et al.: Bull. Amer. Phys. Soc. 54, 48(2009).
4) Y. Sasamoto et al.: RIKEN Acc. Prog. Rep. 43 (2010).
5) S. Michimasa et al.: RIKEN Acc. Prog. Rep. 43 (2010).
6) A. Saito et al.: RIKEN Acc. Prog. Rep. 43 (2010).
7) H. Miya et al.: RIKEN Acc. Prog. Rep. 43 (2010).
8) K. Miki et al.: RIKEN Acc. Prog. Rep. 43 (2010).

RIKEN Accel. Prog. Rep. 43 (2010)

Construction of high resolution beam line for
the SHARAQ spectrometer
Y. Yanagisawa, T. Kubo, K. Kusaka, M. Ohtake, K. Yoshida, T. Ohnishi, Y. Sasamoto, ＊１
A. Saito, ＊１ T. Uesaka, ＊１ S. Shimoura, ＊１ T. Kawabata, ＊２ S. Noji, ＊３ and H. Sakai＊３
High resolution beam line has been constructed for the
SHARAQ spectrometer at RIBF in order to achieve
dispersion matching that can facilitate high-resolution
measurement at the focal plane of the spectrometer. This
beam line is formed by the existing BigRIPS separator1) anda newly constructed beam line that diverges from BigRIPS
and extends up to the target position of SHARAQ. The
SHARAQ spectrometer is designed to achieve a highmomentum resolution Δ p/p of 1/15000 for charged
particles with a magnetic rigidity (Bp) of 6.8 Tm. The highresolution beam line is designed to satisfy the lateral andangular dispersion matching conditions; designing process
involved the precise ion optical calculations2).
The SHARAQ spectrometer is installed in the E20 room.
Since the RI beam emitted from the production target at F0
is achromatically focused at F3 in the normal beamtransport procedure for the BigRIPS, the starting point of
the high-resolution transport2) to the SHARAQ
spectrometer is determined to be F3.

of two 30° bend dipoles (D-H7,D-H8), one quadrupole
doublet(Q-H16,Q-H17), one quadrupole singlet(Q-H18-a,b), three superconducting triplet quadrupole
magnets (STQ-H14,STQ-H15,STQ-H19), and four focal
planes (F-H7,F-H8,F-H9,F-H10), as shown in Fig.1.
To reduce the cost of construction, normal conducting
quadrupole magnets are used for the existing magnets.
Magnets of Q-H16 and Q-H17 are identical to those of PQ3
and PQ2 in the used that were for the SMART spectrograph,
respectively. The magnets of Q-H18-a and Q-H18-b reused
redundant magnets in the E1 room. On the other hand, twodipoles are newly constructed with the same specifications
as the dipole in the BigRIPS.
The maximum magnetic rigidity of the beam line is 8.5
Tm, which is limited by the maximum field gradient of thequadrupole doublets. The basic specifications of themagnetic elements are listed in Table 1.

Table 1. Specifications of the magnetic elements
Fig. 1. Layout of the high resolution beam line.
Up to F6, the beam line shares the magnetic elements with
the BigRIPS. After F6, the high resolution beam line
branches from BigRIPS at the location of the E15 room andbends 60° toward the target. Since the layout of themagnetic elements of the BigRIPS separator has alreadybeen determined, the layout between the branching point
and the target should be optimized to satisfy the dispersion
matching conditions. The high resolution beam line consists
＊１
＊２
＊３

Center for Nuclear Study, University of Tokyo
Department of Physics, Kyoto University
Department of Physics, University of Tokyo

Construction of the high resolution beam line wascompleted in March 2009. Commissioning experiments andtests for verifying the proper functioning of the SHARAQ
spectrometer were performed in March and May 2009.
Results of the commissioning experiments are described inref. 3.
References

1) T. Kubo et al.: Nucl. Instr. Meth. Phys. Res. B 204, 97 (2003).
2) T. Kawabata et al.: Nucl. Instr. Meth. Phys. Res. B 266, 4201
(2008).
3) Y. Sasamoto et al: RIKEN Accel. Prog. Rep. in this report.

- 171 -

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Focus tuning method of the high-resolution beam line for the
SHARAQ spectrometer
Y. Sasamoto,∗1 T. Uesaka,∗1 S. Shimoura,∗1 T. Kubo, Y. Yanagisawa, H. Takeda, H. Sakai,∗2 S. Michimasa,∗1
A. Saito,∗2 S. Ota,∗1 S. Noji,∗2 K. Miki,∗2 H. Tokieda,∗1 H. Miya,∗1 S. Kawase,∗1 T. Kawabata,∗3
G.P.A. Berg,∗4 and SHARAQ team

D8

STQ22

D8

STQ20

STQ21

STQ21

STQ23
D7
STQ23

STQ17

D7
STQ17

DH7

DH7

STQH15

STQ18

STQ18

STQ15

STQ16
STQ15
STQ16

D6

STQ13

STQ14
STQH14
STQ14
D6 STQH14

STQ13

STQ11

STQ12
STQ12
D5
D5
STQ11

STQ10
STQ10
D4
D4
STQ9
STQ9

D3D3

STQ8
STQ8

STQ6
STQ6

STQ7
STQ7

BigRIPSBigRIPS

STQ19

dump

Beam dump

STQ22

ZeroDegree
STQ20
STQ19

Target

STQ4
STQ4

∗4

20 m
20 m

ZeroDegree

STQ5
STQ5

∗3

Center for Nuclear Study, University of Tokyo
Department of Physics, University of Tokyo
Department of Physics, Kyoto University
Department of Physics and Joint Institute for Nuclear Astrophysics, University of Notre Dame

SRC

STQ3

∗2

10
10

SRC

IRC

D2D2

∗1

0
0

STQ2
D1
STQ1

DH8

STQH15

DH8

QH16

QH16

QH17
QH17
QH18
QH18
STQH19
STQH19
S-SDQ
S-SDQ
S-D1
S-D1
S-Q3
S-Q3

SHARAQ
SHARAQ

S-D2
S-D2

Fig. 1. Layout of the high-resolution beam line. It branchesfrom BigRIPS after F6. F3 is the ion-optical starting
point of the high-resolution beam line.

The use of correlations in the standard tuning
method is not always effective in RI-beam experiments.
Figure 2 shows the correlation between the angle at
F3 and the position at F6 for a primary 14 N beamduring the commissioning. The position and angle
are determined experimentally by using multiwire drift
chambers6) . The correlations shown in the left andright panels in the figure were obtained at different
magnetic-field settings. Therefore, the slopes in thepanels should be different. However, it is difficult todetermine the difference.
20

20

15

15

Angle at F3 (mrad)

Angle at F3 (mrad)

New missing-mass spectroscopy involving RI beams
will be conducted at the RIBF with the SHARAQ
spectrometer1) . The SHARAQ spectrometer is designed to achieve a resolving power of p/δp = 1.5 × 104
and a high angular resolution δθ of 1 mrad for particles
with a maximum magnetic rigidity Bρ of 6.8 Tm. In
order to avoid loss of energy resolution due to the momentum spread of the RI beams, the dispersion matching (DM) technique is applied in high resolution measurements2) .
A high-resolution beam line has been constructed3)
according to the ion optical design described in Ref. 2.
Figure 1 shows the layout of the high-resolution beamline. The RI beam emitted from the production target
at F0 is achromatically focused at F3. F3 is the ionoptical starting point of the high-resolution beam line.
Beyond the starting point, the beam line consists of 30
superconducting quadrupole magnets, 4 normal conducting quadrupole magnets, and 5 dipoles. In orderto reduce the tuning time for the beam line, the primary settings for each magnet were determined fromthe ion optical calculations performed on the basis ofprecise magnetic-field-measurements4) . Fine tuning is
still needed for the high-resolution measurements. In
this report, the tuning method that is used in thecommissioning of the high-resolution beam line for the
SHARAQ spectrometer5) is described.
Measurement of the transfer matrix R, which relates
the initial and final coordinate vectors X and X  asX  = RX, is required for fine-tuning. The elements of
R are usually obtained from the correlations between
phase-space variables of two focal planes. For example, in order to tune the focus condition for the matrix
element (x|a)if = 0, where each digit in the subscript
denotes the corresponding focal plane, we use the correlation between the position xf at the final point andthe angle ai at the initial point. The slope of theplot corresponds to the magnitude of (x|a)if . Thus,
for beam-tuning the high-resolution beam line for the
SHARAQ spectrometer between F3 and F4 shown in
Fig. 1, the correlation between the positions at F4 andthe angles at F3 can be used. In this report, we callthis method, which involves the use of the correlation
between xf and ai , the standard focus-tuning method.

10
5
0
-5
-10
-15
-20

-40

-20

0

20

Position at F6 (mm)

40

10
5
0
-5
-10
-15
-20

-40

-20

0

20

40

Position at F6 (mm)Fig. 2. Correlation between the angles at F3 and the positions at F6 for a primary 14 N beam under different
field settings. The slope corresponds to the magnitudeof (x|a)36 .

This difficulty is caused by the spread of the image at
the focal plane, which result from the large dispersion
and beam-energy spread. The dispersion at the focal- 172 -

1the terms on the left side of Eq. (2) and the angle
at FH7, a7 , under a different magnetic-field setting.
In Fig. 4, it is clearly seen that the slope, which indicates the magnitude of (x|a)76 , is different. If thestandard tuning method is applied using the correlation between x6 and a7 , the spread of the image caused
by x7 because of the large dispersion smear (x|a)76 information. Fine-tuning is thus possible by momentumindependent focus tuning.
100
50

x7 (mm)planes in the DM mode are summarized in Table 1.
When the primary beam with a momentum spread ∆pof ∼±0.1% is used, the horizontal beam image, for example, at F6, spreads by about ±8 mm because of
the dispersion. The beam spread smears the information for (x|a). Even if momentum slits are used toreduce the beam momentum, the reduced momentum
is almost on the same order as the momentum of the
primary beam. The standard tuning method could beapplied between F3 and F4 as described above because
the spread caused by the dispersion is not considerablylarger than that at other points.
Table 1. Design dispersion (x|δ) for the DM mode.
F6
76.7

FH7
−73.7

FH9
229

FH10
150

-100
-100

The term on the left-side of in Eq. (1) is independentof the beam momentum; by eliminating the spread dueto the beam-energy spread at FH7.
Next, we will consider a simple example between
F6 and FH7. In the following, the left-hand side isindependent of the beam momentum:(2)

In this equation, the dispersive term is not included because there is no dipole magnet between F6 and FH7.
In Eq. (2), the particles are assumed to be emitted from
FH7 to F6. To evaluate the left-hand side of Eq. (2),the magnification (x|x)76 should be experimentally deduced. Figures 3 and 4 show the correlation between
F6 and FH7. Figure 3 shows the correlation of x6 withx7 and the slope of this corresponds to the magnification (x|x)76 . Figure 4 shows the correlation between

2

-50

0

50

100

x6 (mm)One of the methods to reduce the effect of the beamenergy spread involves the use of the measured beam
momentum and the matrix elements. Although thismethod is simple and valid, a considerable amountof time is required to experimentally deduce both thebeam momentum and the matrix elements, which arecoupled to each other.
Another method, which we introduce, is to use quantities that do not depend on the beam momentum.
In this report, we call this method the momentumindependent tuning method. This method is effective
for tuning in the focal planes that exhibit a large dispersion. Let us consider focus tuning between F4 andFH7 for the purpose of achieving (x|a)74 = 0. The
beam momentum δ could be assumed to be x7 /(x|δ)37
in the largely dispersive focal plane of FH7. Then,phase-space variables are related in first-order opticsas(x|δ)74(1)x4 − (x|x)74 −x7 = (x|a)74 a7 .
(x|δ)37x6 − (x|x)76 x7 = (x|a)76 a7 .

-50

- 173 -

Fig. 3. Correlation between positions at F6 and FH7,
which are represented as x6 and x7 , respectively. The
slope corresponds to the magnification between F6 andFH7, namely (x|x)67 .

30

30

Angle at FH7 (mrad)

F4−19

Angle at FH7 (mrad)

Focal plane
Design value(mm/%)

0

20
10
0
-10
-20
-30

20
10
0
-10
-20
-30

-20

-10

0

10

x7-(X,X)x6

20

-20

-10

0

10

20

x7-(X,X)x6

Fig. 4. Correlation between the term on the left side ofEq. (2) and the angle at FH7, a7 , under different
magnetic-field settings. It is clearly seen that the slope,which corresponds to the magnitude of (x|a)67 , is different.

This is an expeditious tuning method since it does
not involve a complicated procedure. This method facilitates the quick optimization for the magnetic settings of the high-resolution beam line for the SHARAQ
spectrometer. Quick beam tuning is important for
beam lines with many focal planes.
References
1) T. Uesaka et al.: Nucl. Instrum. Meth. Phys. Res.
B 266, 4218 (2008).
2) T. Kawabata et al.: Nucl. Instrum. Meth. Phys. Res.
B 266, 4201 (2008).
3) Y. Yanagisawa et al.: Bull. Amer. Phys. Soc. 54, 48(2009).
4) H. Takeda et al.: Private correspondence.
5) T. Uesaka et al.: RIKEN Accel. Prog. Rep. 43, (2010).
6) A. Saito et al.: RIKEN Accel. Prog. Rep. 43, (2010).

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Focal Plane Detector System of SHARAQ Spectrometer
S. Michimasa,� 1 H. Tokieda,� 1 S. Noji,� 2 S. Ota,� 1 S. Shimoura,� 1 T. Uesaka,� 1 H. Sakai,� 2
P. Roussel-Chomaz,� 3 J-F. Libin,� 3 P. Gangnant,� 3 and C. Spitaels� 3[SHARAQ spectrometer, cathode-readout drift chamber]
The consturuction of the SHARAQ spectrometer1)
and the high-resolution beam line2) was completed at
the RI Beam Factory (RIBF) at RIKEN in March
2009, and commissioning beam runs were performed
in March and May 2009. During the beam runs, we
examined dispersion-matching ion optics and evaluated the performance of the detectors installed in the
focal planes of the beam line and that of the spectrometer. Valuable information on the basic performance of the high-resolution spectrometer system was
obtained. This report describes the basic performanceof the detector system installed in the ﬁ nal momentumdispersive focal plane of the SHARAQ spectrometer.
Figure 1 shows the detector setup used in the commissioning runs. Two tracking detectors and two plastic scintillators were installed in the ﬁ nal focal plane of
the SHARAQ spectrometer. The focal plane is located579 706

3040

35o

Beam

Exit of D2 Magnet

Focal Plane

CRDC1

Plastic Scintillators

CRDC2
Aluminium Window

SHARAQ
D2 Magnet

Fig. 1. Detector setup in the ﬁ nal focal plane of SHARAQ
in the commissioning runs (top view). The detector system consists of two tracking detectors and two plastic
scintillators.

3.04 m downstream from the exit of the SHARAQ
D2 magnet and inclined at 35 degrees relative to thecentral orbit. The beam particles passed through the
tracking detectors installed in vacuum and then passed
into the air through a 10 mm-thick aluminum window.
The plastic scintillators were placed downstream of thealuminum window.
The plastic scintillators were used to measure thetimings of beam particles at the focal plane and tomeasure the energy deposits in them. The two-layer
conﬁ guration of the scintillators was eﬀective in rejecting cosmic-ray events. The measured results ob� 1

� 2
� 3

Center for Nuclear Study, University of Tokyo
Department of Physics, University of TokyoGANIL, France

tained from each scintillator were read out by two photomultiplier tubes attached to the left and right of thescintillators. The size of the plastic scintillator was
1110 (H) × 300 (V) × 5 (T) mm3 . Charge and timing
data obtained from the scintillators were collected using charge-to-time converters (QTCs)3) and multi-hit
TDCs. We were able to identify 12 N and 11 C particles
with a separation of more than 5 σ.
The tracking of particles were performed using two
cathode-readout drift chambers (CRDCs)4,5) . The
CRDCs have manufactured in January 2009 in collaboration with the detector developing group of GANIL.
The structure of the CRDC is described in detail in
Ref.5) . In the commissioning runs, the CRDCs wereoperated with isobutane gas at 15 or 30 torr for thedetection of various light nuclei such as t, 6 He, 9 Li,
12B, and 12,14 N at around 200A–250A MeV.
The CRDC transmits two signals from the anodewires and two multiplexed signals from the cathodepads. The anode signals were used to deduce thedrift time and the charge of secondary electrons. The
preampliﬁ ers for the anodes were charge sensitive; they
had a gain of 0.9 V/pC and a time constant of 20 � s.
The time reference for the measurement of the drift
time was provided by the plastic scintillators. Since
the anode signal is generated when an avalanche occurs around the anode wires, the drift times are determined by the diﬀerence between the anode timing
signal and the timing signal of the plastic scintillator.
We operated CRDCs with drift electric ﬁ elds of 83.3
(140) V/cm using 15-(30-)torr isobutane. The drift
velocity of the secondary electrons were 5.9 cm/� s at
15 torr and 5.3 cm/� s at 30 torr, respectively. These
values are approximately equal to those evaluated byusing the GARFIELD code6) . Under the above mentioned conditions, the vertical position resolution wasapproximately 0.9 mm (FWHM), which is inferior to
the design value by a factor of 2. We are continuing
data analysis in order to improve the position resolution.
Figure 2 shows the avalanche gain measured by
CRDCs operated with 30-torr isobutane as a functionof the voltage supplied to the anode wires. CRDC1(CRDC2) corresponds to the upstream (downstream)
tracking chamber in Fig. 1. The avalanche gain of
CRDC2 was consistently smaller than that of CRDC1.
This diﬀerence in the gains is considered to be dueto the diﬀerence in their conﬁ gurations. In CRDC1,
potential wires are placed between anode wires, while
CRDC2 has no potential wires; this has been schemati-- 174 -

1

simultaneously. In the commissioning run, we applied
anode voltages that were 30 V higher than the voltages
for which the detection eﬃ ciencies were 100%. At the
supplied voltage, induced charges were distributed overapproximately 10 cathode pads, and the maximum induced charge was present around the middle of the
dynamic range of GASSIPLEX. The horizontal position was deduced by ﬁ ttings of the charge distributions
to a function

Fig. 2. Avalanche gain of CRDCs measured using isobutane gas at 30 torr. The deﬁ nitions of CRDC1 and
CRDC2 are described in the text.

cally depicted in Fig. 2 of Ref.5) . However, we demonstrated that both the CRDCs achieved an avalanchegain higher than the required gain of 104 .
The detection eﬃ ciency of the CRDC is deﬁ ned here
as the ratio of the detection using the anode signal
to the detection by the plastic scintillators. Figure 3
shows the detection eﬃ ciency of CRDC1 as a functionof the supplied anode voltage. Fig. 3(a) shows the detection eﬃ ciency curves for 14 N ions at 250A MeV in
the 15- and 30-torr operations, and Fig. 3(b) shows
the detector eﬃ ciency for lighter particles at around
220A MeV in the 30-torr operation. It was conﬁ rmed

q(x) = a1 · sech2 [π(x − a2 )/a3 ] ,where ai (i = 1, 2, 3) are ﬁ tting parameters9) . The
horizontal positions corresponds to a2 . The typicalresolutions of horizontal position were estimated to be
500 � m and 700 � m (FWHM) for 14 N at 250A-MeV
and 6 He at 220A-MeV, respectively.
In summary, we examined the detector system installed in the ﬁ nal focal plane of the SHARAQ spectrometer in the commissioning runs of the SHARAQ
spectrometer by using light radioactive isotopes at
200A–250A MeV. All the detectors were operated successfully and the basic data on their performance wereobtained. Identiﬁ cation of particles with atomic numbers Z of around 7 was performed by using plastic
scintillators. Under the present conditions, the position resolution of CRDCs was estimated to be 0.9 mm(FWHM) in the horizontal direction and 0.7 mm(FWHM) in the vertical direction. In the ﬁ rst experiment10) that was performed in November 2009, thefocal plane detector system was used, and the data on
the (t,3 He) reactions at 300A MeV were obtained. Further analysis is now in progress in order to optimize thedetectors’ parameters and to improve the data-analysis
algorithm used in the detectors.
References

Fig. 3. (a) Detection eﬃciency for 250A-MeV 14 N ions withthe 15- and 30-torr operations. (b) Detection eﬃciency
for t, 6 He, 9 Li particles with the 15- and 30-torr operations.

that the CRDCs designed for SHARAQ will achieve
detection eﬃ ciencies of approximately 100% for 200AMeV tritons even when operated using 30-torr isobutane gas.
The horizontal position in the focal plane is determined by the charge distribution on the cathodepads. The charge signals from the cathode pads wereread out by using GASSIPLEX chips7) and a CRAMS
module8) . The pedestals of the channels the GASSIPLEX chip ranged from 60 to 70 mV and were stable(< 2 mV) over the 10-day measurements. The trackand-hold signals were generated by the timing of theanode signal of the CRDC under the condition thattwo plastic scintillators and the anode were detected2- 175 -

1) T. Uesaka et al.: Nucl. Instrum. Methods Phys. Res. B
266, 4218 (2008).
2) T. Kawabata et al.: Nucl. Instrum. Methods Phys. Res.
B 266, 4201 (2008); Y. Yanagisawa et al.: Bull. Amer.
Phys. Soc. 54, 48 (2009).
3) H. Nishino et al.: Nucl. Instrum. Methods Phys. Res. A
610, 710 (2009).
4) M.H. Tanaka et al.: Nucl. Instrum. Methods Phys. Res.
A 362, 521 (1995).
5) S. Michimasa et al.: CNS-REP-80, (2009) 55.
6) R. Veenhof, GARFIELD, CERN Program Library
W5050.
7) The GASSIPLEX is a re-designed chip of the AMPLEX
by J.C. -Santiard of CERN. The AMPLEX is describedin E. Beuville et al.: Nucl. Instrum. Methods Phys. Res.
A 288, 157 (1990).
8) V551 C.A.E.N sequencer User Guide, V550 C.A.E.N
CRAMS User Guide.
9) K. Lau and J. Pyrlik: Nucl. Instrum. Methods Phys.
Res. A 366, 298 (1995).
10) K. Miki et al.: RIKEN Accel. Prog. Rep. 43, (2010).

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Development of Beamline Detectors for BigRIPS andHigh-Resolution Beamline
A. Saito,∗1 S. Shimoura,∗1 H. Miya,∗1 K. Miki,∗2 T. Yoshida,∗3 T. Kawabata,∗4 S. Itoh,∗2 K. Itahashi M. Sasano
Y. Shimizu,∗1 Y. Shimbara,∗5 S. Kawase,∗1 H. Kurei,∗1 S. Michimasa,∗1 K. Nakanishi,∗1 S. Noji,∗2 S. Ota,∗1
Y. Sasamoto,∗1 H. Tokieda,∗1 T. Uesaka,∗1 and H. Sakai∗2
1

Introduction

We are developing low-pressure multiwire drift
chambers (LP-MWDCs) and plastic scintillators to
be used in BigRIPS and the high-resolution beamline(HRBL), for SHARAQ spectrometer experiments1) .
Figure 1 shows a layout of BigRIPS, HRBL, andSHARAQ spectrometer. LP-MWDCs are installed at
F3, F6, F-H7, F-H9, and F-H10. A list of the LPMWDCs is shown in Table 1. Plastic scintillators are
installed at F3, F-H7, F-H9, and F-H10. Herein, we
report on the developments made to LP-MWDCs andthe plastic scintillators as well as the commissioning
performed in March, May, and November 2009.

Table 1. List of LP-MWDCs in BigRIPS and HRBL. X
and Y are the stripped cathode with delay-line readout;
x, u, and y are anode layers.

 





 





be very low, i.e. approximately 10−4 of the radiation length, so that multiple scattering in the detectors is reduced to approximately 0.1 mrad. The eﬃciency should be as high as possible even for light RI
beams such as 200-MeV/nucleon 8 He beams. The position resolution is required to be less than 300 µm in
FWHM. The maximum counting rate should be 1 MHz
for the dispersive beam transport. Energy loss information should be obtained by the tracking detectors
for particle identiﬁcation of the RI beam and for rejecting in-ﬂight β-decay events.
LP-MWDCs are being developed in order to achieve
the above mentioned performance. Low-pressure operation at around 10 kPa must be carried out to reduce
multiple scattering in the detector to 0.1 mrad.



Focal
Plane

 



















F3

 




F6
F-H7

 








 



F-H9
F-H10










 








 


 



2

 

 


Fig. 1. LP-MWDCs and plastic scintillators in BigRIPS
and HRBL.

The tracking detectors used must fulﬁll certain requirements. The thickness of the detectors should
∗2
∗4
∗5
∗6

DC31
DC32
DC61
DC71
DC72
DC91
DCX1
DCX2

Activearea[mm2 ]
80 × 80
80 × 80
216 × 144
216 × 144
216 × 144
216 × 144
216 × 144
144 × 144

Cell
size
[mm]
5
5
9
9
9
9
9
9

Conﬁguration
xx’yy’xx’yy’
xx’yy’
XyuxY
XyuxY
XyuxY
XyuxY
XyuxY
XyuxY

MWDCs at F6, F-H7, F-H9, and F-H10




∗1

Name

Center for Nuclear Study, University of Tokyo
Department of Physics, University of Tokyo
Department of Physics, Rikkyo University
Department of Physics, Kyoto University
Department of Physics, Niigata University

Figure 2 shows a schematic view of DCX2, which includes three anode layers (x, u, and y) and two stripped
cathodes (X and Y). The u wires are tilted by 30◦ withrespect to the x wires. The cathodes on the outer side
are stripped in the horizontal and vertical directions (Xand Y). The stripped cathodes provide redundant position information and information about the energy lossof the RI beam for particle identiﬁcation. The signals
from the stripped cathodes are read out using delaylines (DL’s). Three high voltages can be supplied individually to the stripped cathodes, other cathodes, andﬁeld wires. The signals from the DLs are ampliﬁed bya Kaizu 3356 preampliﬁer. The signals from the anode wires are ampliﬁed and discriminated by a REPIC
RPA-130/131 64-channel preampliﬁer and discrimina-- 176 -

1

tor cards. The timing signals from RPA-130/131 aredigitized by CAEN V1190A/B multihit TDCs.

3

Plastic scintillators were installed at F3, F-H7, FH9, and F-H10. Eljen Technology EJ-212 scintillators
were used. The dimensions of SF3 and the others were
100 × 100 × 1 mm3 and 220 × 150 × 3 mm3 , respectively. The scintillation light was read out by two
Hamamatsu R7600 photomultiplier tubes with lightguides attached to both ends of the scintillator.




4
   
 




 





    

Fig. 2. Schematic of DCX2.

Figure 3 shows the detector setup at F-H10. Two
LP-MWDCs are separated by a distance of 500 mm inorder to track the RI beams with an angular resolution
better than 1 mrad.










Fig. 3. Detector setup at F-H10.

2

Plastic scintillators- 177 -

Commissioning

Commissioning of HRBL and the SHARAQ spectrometer was performed in March, May, and November 2009. Eight LP-MWDCs listed in Table 1 wereused in the commissioning. In March and May 2009,
we evaluated the tracking eﬃciencies and resolutionsof the LP-MWDCs at F6, F-H7, F-H9, and F-H10, at
10 kPa for the RI beams produced by fragmentation of
the 14 N beam. We also evaluated the performances at
50 kPa for triton and 3 He beams, in November 2009.
Details of the data analysis are described elsewhere7) .
References
1) T. Uesaka et al.: Nucl. Instrum. Meth. in Phys. Res.
B266, 4218 (2008).
2) T. Kawabata et al.: Nucl. Instrum. Meth. in Phys. Res.
B266, 4201 (2008).
3) K. Miki et al.: RIKEN Accel. Prog. Rep. 42, 175 (2009);
K. Miki et al.: CNS Ann. Rep. 2008 (2009).
4) H. Miya et al.: CNS Ann. Rep. 2007, 60 (2008);
H. Miya et al.: RIKEN Accel. Prog. Rep. 42, 173(2009).
5) T. Yoshida et al.: CNS Ann. Rep. 2008 (2009).
6) H. Kumagai et al.: Nucl. Instrum. Meth. in Phys. Res.
A470, 562 (2004).
7) H. Miya et al.: CNS Ann. Rep. 2008 (2009); H. Miya etal.: RIKEN Accel. Prog. Rep. 43, (2010).

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Current status of SAMURAIK. Yoneda, N. Iwasa,∗1 T. Kawabata,∗2 T. Kobayashi,∗1 Y. Kondo,∗3 T. Kubo, K. Kusaka,
T. Motobayashi, T. Murakami,∗2 Y. Nakai, T. Nakamura,∗3 J. Ohnishi, T. Ohnishi, H. Okuno, H. Otsu,
H. Sakurai, H. Sato, Y. Satou,∗4 K. Sekiguchi, and Y. Togano
This report describes the current status of construction of the experimental apparatus, SAMURAI.
SAMURAI (Superconducting Analyzer for MUltiparticles from RAdio Isotope beam) is a largeacceptance multiparticle spectrometer to be constructed in RIBF. A schematic illustration of SAMURAI is shown in Fig. 1. The main component of
SAMURAI is a large-gap (80 cm) superconducting
dipole magnet with the maximum bending power of
7 Tm. This magnet will be used for the analysis of momentum of heavy projectile fragments and projectilerapidity protons with large momentum and angular acceptance. The large gap also enables measurement ofprojectile-rapidity neutrons with large angular acceptance in coincidence with heavy projectile fragments.
SAMURAI can be used in a variety of applications inexperiments with the RI beams provided by BigRIPS.
When used in experiments on breakup of neutronrich and proton-rich nuclei, SAMURAI’s large acceptance enables efficient heavy ion(HI)-neutron and HIproton coincidence measurements that are required forinvariant-mass spectroscopy. SAMURAI is also suitable for use in missing-mass spectroscopy, in whichmeasurement of charged particles after the reaction not
only enables the tagging of the reaction channels but
also provides knowledge of the decay modes; this ispossible because of the multi-particle detection capability. SAMURAI is also used to scrutinize scattering
reactions of light nuclei, such as polarized deuteronscattering on proton, in order to study fundamental
nucleon-nucleon interactions, including three-nucleon
force effects. We also plan to install a time projection
chamber in the large gap of the SAMURAI magnet,
which is used mainly for reaction studies such as investigation of density dependence of the asymmetry
term in the nuclear equation of state.
The construction is funded for four years from fiscal
year (FY) 2008. At present, designing and construction of the magnet and detectors are underway andare proceeding according to the schedule, and the firstexperiment will be performed in summer 2011.
The magnet is an H-type dipole with cylindricalpoles of diameter 2 m. Each pole is surrounded bya superconducting coil that generates a magnetic fieldof about 3 T across the pole gap of 80 cm at the centerof the magnet. The yoke and pole of the magnet have
∗1
∗2
∗3
∗4

Fig. 1. Schematic image of SAMURAI system. SAMURAI
consists of a large bending magnet that is surroundedby particle detectors. The magnet is a superconducting dipole magnet with the maximum bending power of
7 Tm and a large pole gap of 80 cm. Heavy-ion detectors, neutron detectors, and proton detectors, are installed around the magnet. The detector configurationis changed depending on experimental requirements.

been designed, and at present, the designs of the coiland cryogenic system are being finalized 1) .
In the following sections, an overview of the detectors to be prepared for SAMURAI is given. Threetypes of detectors, namely, heavy ion detectors, neutron detectors, and proton detectors, are to be prepared. The heavy ion detectors consist of 1) beam
detectors, 2) tracking detectors that are placed before
and after the magnet, 3) detectors used for particle
identification (PI) and time-of-flight (TOF) measurement.

Department of Physics, Tohoku University
Department of Physics, Kyoto University
Department of Physics, Tokyo Institute of Technology
Department of Physics and Astronomy, Seoul National University, Korea- 178 -

• Beam Detectors
The beam particles are detected in front of thetarget to obtain the information required for PI
and the beam profiles, which is used to generate
an important trigger signal.
The beam timing is measured by the plastic scintillators (SBT). Two sets of plastic scintillators,i.e., two 1-mm-thick scintillators and two 0.5-mmthick scintillators are prepared. Each scintillator has an active area of 100 mm × 100 mm,
and both ends of each scintillator are PMTs
(HAMAMATSU H1949-50MODB). Plastic scintillators with a hole are prepared and are used asbeam halo veto detectors (BV). Three BVs witha hole of diameter 20 mm, diameter 25 mm, and1

diameter 30 mm, are prepared. These detectors
are ready for use.
An ion chamber (ICB) is installed in the beamline
to measure the energy loss of the beam particles.
The ICB has an active area of 150 mm × 150 mm;
it is 420-mm thick, and has multiple cathodes andanodes that are vertical to the beamline. An ICB
performance test was performed.
Beam profiles are measured by two multiwire drift
chambers (BDC1, BDC2) or two multiwire proportional chambers (BPC1, BPC2, not shown in
the figure). The active areas of BDC and BPC
are 80 mm (V) × 80 mm (H) and 150 mm (V)× 240 mm (H), respectively. BDC is designed towork at low gas pressure, so that the detector canbe installed in the beamline. The performance of
BDC at low pressure was tested. These detectors
have already been fabricated.
• Tracking Detectors
The HI tracking detectors (FDC1, FDC2) that are
to be set infront of and behind the magnet will
be constructed. FDC1 will be installed between
the target and magnet. It is expected that thebeam particle density at FDC1 is high, and hence
the operation rate should be high. For this purpose, FDC1 is designed to have a drift distance of
5 mm. FDC1 has an active area of 340 mm (V) ×
620 mm (H) to allow projectile-rapidity neutrons
to pass through the detector aperture. FDC1 hasalread ybeen fablicated.
FDC2 is placed behind the magnet in order
to measure HI tracks. Particles will spread inspace behind the magnet, and hence FDC2 is designed to cover a large area (∼810 mm (V) ×2230 mm (H)). FDC2 is being designed, and so
far structural calculations have been performed.
FDC2 will be constructed in FY2010.
• Detectors for PI and TOF measurement
Plastic scintillator hodoscopes (HODF, HODP)
are used for TOF measurement. Each hodoscopeconsists of 16 plastic scintillators (1200 mm (V) ×
100 mm (H), 10 mm thick). Both ends of the scintillators are coupled to the PMTs (HAMAMATSU
H7195MODB). Velocity measurement can also be
performed by using total internal-reflection-type
Cherenkov detectors (TIRC).
An ion chamber for reaction fragments (ICF) is
installed for measuring the energy loss of HIs.
The ICF has an active area of approximately
400 mm (V) × 700 mm (H). Pure CsI scintillators are prepared for use as total energy detectors(TED). The crystal size is 100 mm × 100 mm
× 50 mm, and the crystal is coupled to a PMT(HAMAMATSU R6233ASSY). The performancesof TIRC and TED were tested. All these detectors
are ready to be fablicated.
• Neutron Detectors
2

A neutron detector system, called NEBULA(NEutron Detection system for Breakup of Unstable Nuclei with Large Acceptance), is placedat forward angles. NEBULA consists of four
sets of detector array, and each set consistsof 60 neutron detection plastic scintillators(120 mm × 120 mm × 1800 mm), which arearranged in two layers and cover an area of1800 mm (V) × 3600 mm (H), and 12 chargedparticle-veto scintillators (320 mm × 10 mm
× 1900 mm).
Two PMTs (HAMAMATSU
R7724ASSY) are coupled to both ends of eachscintillator. The angular acceptance of NEBULA
is ±5◦ (V) and ± 10◦ (H), which corresponds toalmost 100% coverage for breakup events with arelative energy of 3 MeV and about 40% for a
relative energy of 10 MeV. Neutron detection efficiency with full volume is estimated to be about
60% for the projectile-rapidity neutrons. Half therequired number of neutron detection scintillatorsand full veto detectors are ready for use.
• Proton Detectors
The TOF of protons is measured by the hodoscope, which has been described earlier. A
tracking detector that is to be placed after themagnet (PDC, not shown in the figure) is preparedseparately so that proton-HI coincidence measurement can be carried out. PDC will be fablicatedby May 2011.
The tracking detector that is to be placed before
the magnet should be capable of detecting protons
even when both protons and HIs hit the detector;
a gas detector cannot be used for this purpose.
Therefore, layers of silicon strip detectors are installed between the target and magnet. Here, thedetector should be capable of detecting protons
as well as heavy ions, leading to the generationof signals ∼2500 times larger than proton signals.
Additionally, the number of channels is as high as∼2500. In order to overcome these difficulties, westarted developing a new ASIC front-end circuits.
The circuits are being designed and tested, andthe results are reported by M. Kurokawa et al . 2) .
The magnet will be assembled in Room E21 in RIBF
building in autumn 2010, and the assembling will becompleted by early 2011. The detectors and electronics will be simultaneously developed. After some tests
and commissionings, the first SAMURAI experimentis expected to be performed in early 2012.
References
1) H. Sato et al.: RIKEN Accel. Prog. Rep. 43, 180(2010).
2) M. Kurokawa et al..: RIKEN Accel. Prog. Rep.
43, 182 (2010).

- 179 -

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Design of large-gap superconducting dipole magnet for SAMURAI
spectrometer
H. Sato, N. Iwasa,∗1 T. Kawabata,∗2 T. Kobayashi,∗1 Y. Kondo,∗3 T. Kubo, K. Kusaka, T. Motobayashi,
T. Murakami,∗2 T. Nakamura,∗3 J. Ohnishi, T. Ohnishi, H. Okuno, H. Otsu, H. Sakurai, Y. Satou,∗4
K. Sekiguchi,∗1 Y. Togano, and K. Yoneda

∗1
∗2
∗3
∗4

Department of Physics, Tohoku University
Department of Physics, Kyoto University
Department of Physics, Tokyo Institute of Technology
Department of Physics and Astronomy, Seoul National University, Korea

Fig. 1. Schematic view (a) and cross-sectional views (b)(c)of the superconducting dipole magnet.

6

(a)

5

3.0

4

pole diameter

2.0

3
2

TOSCA calculation

1
0

(b)

By(z) [ T ]central magnetic field [ T ]A large-acceptance spectrometer named SAMURAI
is under construction at the RIKEN RI Beam Factory (RIBF).1,2) The SAMURAI spectrometer consistsof a large-gap superconducting dipole magnet, heavyion detectors, neutron detectors, and proton detectors.
The purpose of the spectrometer is to perform kinematically complete measurements of multiple particles
emitted in reactions induced by RI beam. The superconducting dipole magnet is required to have a rigidity
resolution of about 1/700 (rms) at P/Z = 2.2 GeV/c,
which corresponds to a magnetic rigidity Bρ of 7.3 Tm,
where P is a momentum and Z is an atomic number.
It should also be able to identify particles having mass
numbers up to 100. The superconducting dipole magnet has been designed to satisfy these requirements on
the basis of 3-dimensional magnetic field calculations
performed using the code OPERA-3D/TOSCA.
Figure 1 shows the schematic view and the crosssectional views of the dipole magnet. The magnet is an
H-type dipole, having cylindrical poles with diametersof 2 m, a large pole gap of 880 mm, and circular superconducting coils. To change the experimental setup,the magnet can be rotated about the y-axis. The upperand lower superconducting coils are installed in theirrespective cryostat and cooled separately by a liquid
helium bath. The maximum magnetomotive force is
1.9 × 106 AT/coil, which generates a magnetic field of
about 3 T at the center of the poles in the medianplane. The magnet is designed to have a maximum
bending power (BL integral) of 7 Tm.
Figure 2(a) shows the excitation curves of the dipole
magnet. The points on the solid line are the values
calculated by using TOSCA, while the dotted straightline is obtained by assuming that the magnetic permeability of iron is infinity. The y component of themagnetic fields, By (z), obtained with a magnetomotive
force of 1.9 × 106 AT/coil is plotted along the z-axis in
Fig. 2(b). Note that the schematic representation of
the coordinates is given in Fig. 1. The integral of By (z)for the region from z = -2 m to z = +2 m is calculated
to be 7.05 Tm, which satisfies the design requirement
for the bending power. The main parameters of themagnet are listed in Table 1.
Fig. 3(a) shows the By (z) distribution calculated formagnetic permeability=infinity

0

0.5
1.0
1.5
2.0
magnetomotive force [ MAT/coil ]yoke area

1.0
0
-2.0

-1.0

0
z[m]

1.0

2.0

Fig. 2. (a) Excitation curve. (b) y component of magnetic
field, By (z), plotted along z-axis (1.9 × 106 AT/coil).

different central magnetic fields. In the case of the
maximum magnetic field of 3.1 T, the peak value of thefringing fields was calculated to be −2.6×10−3 T. Thisvalue is acceptable for achieving the required magnetic
rigidity resolution.
We checked the effects of two kinds of holes on themagnet (see Fig. 1). The first type of hole is a rectangular hole (490 mm × 260 mm) that is located at thehorizontal center of each field clamp. This hole is used
for installing cryocoolers. The other hole serves as abeam path at each side yoke, whose cross-sectional size

- 180 -

1

10

By(z) [ x10 -4 T ]Table 1. Parameters of the superconducting dipole magnet
and the superconducting wire.
Magnetnumber of turns
current
magnetomotive force
current density of coilfield at the pole center(median plane)
BL integral at 3.1 T
maximum magnetic field
in a coilinductancestored energy
inner diameter of coilouter diameter of coilcross section of coilweight of coilpole shapepole gap
pole diameter
pole heightyoke width
yoke depth
yoke heightyoke weightH-type,superconducting
3411 turns/coil
560 A
1.9 × 106 AT/coil
66.0 A/mm2
3.1 T

2.9 T
2.7 T
2.5 T
2.5

3.0

3.5
z[m]

4.0

4.5

10

7.05 Tm
5.26 T

(ii)

-10

(iii)
(i)with two kinds of holes(actual yoke)

-20

-40
2.0

2350 mm2710 mm
180 × 160 mm21783 kg/coilcircular
880 mm2000 mm
500 mm
6700 mm3500 mm4640 mm566140 kg

5.0

(b)

(i)

0

(ii)without holes

-30

212 H
33 MJ

(iii)with holes on the field clamps(iv)(iv)with holes on the side yokes

2.5

3.0

3.5
z[m]

4.0

4.5

5.0

Fig. 3. Magnetic field distribution By (z) in the fringing
field region: (a) for different central magnetic fields and(b) with the holes in the field clamps and the side returnyokes.

Table 2. List of the cryocoolers for one cryostat.

cryocooler
cooling
powerheat load

NbTi/Cu
3 mmφ
5.0∼6.0
PVF(≥40 µm)∼28 µmφ∼1760∼88 mm≥100>4000 A at 3 T>3290 A at 4 T>2690 A at 5 T>2150 A at 6 T

is 400 mm × 400 mm.
The By (z) distribution when the field clamps did
and did not have holes is shown in Fig. 3(b) by lines(iii) and (ii), respectively. Although some effects of
the holes can be recognized in the figure, the effects
only appear in a narrow region from z = 2.25 m toz = 2.75 m, and the BL obtained in the region of
2.2 ≤ z ≤ 5 m decreases by 5%.
The influence of the beam paths on the side yokes isshown by line (iv) in Fig. 3(b). The presence of theseholes increases the peak value of the fringing fields by
36% and also increases the BL by 30%.
Line (i) in Fig. 3(b) represents the By (z) distribution
when the holes are present in both the field clamps and

2

3.1 T

-20

-40
2.0

Superconducting wirematerial
diameter
Cu/SC ratio
insulation
filament diameter
number of filaments
twist pitch
RRR
critical current at 4.2 K

-10

-30

By(z) [ x10 -4 T ]

type

(a)

0

- 181 -

liquid-He
vessel
GM-JT×2
3.5 W@4.3 K
4.11 Wthermal shield
20 K
80 K
GM×2
5W
45 W
@20 K
@40 K
4.96 W 78.22 W

current
lead
GM×1
60 W
@40 K
53.94 W

the side yokes. It is observed that the effects of thesetwo kinds of holes (see Fig 3(b,iii) and (b,iv)) cancel
each other, and as a result, the total effect of the holeson the fringing fields becomes small (as indicated by
the change from Fig 3(b,ii) to (b,i)). Thus, we conclude
that the presence of these holes does not have a serious
degrading influence upon the fringing fields.
The upper and lower superconducting coils are installed in separate cryostats and cooled by a small cryocooler system mounted on each cryostat. Thus, there
are no superconducting links between the coils. Table 2 lists the cryocoolers for one cryostat. There are atotal of 10 cryocoolers for this superconducting dipole
magnet.
The assembly and installation of the superconducting dipole magnet will start at the RIBF site in autumn
2010 and will be completed by early 2011.
References
1) K. Yoneda et al.: RIKEN Accl. Prog. Rep. 42, 26(2009).
2) K. Yoneda et al.: RIKEN Accl. Prog. Rep. 43, 178(2010).

RIKEN
Accel.
RIKEN
Accel.Prog.
Prog.Rep.
Rep.4343(2010)(2010)

Front-End Electronics for SAMURAI Si Detectors
M. Kurokawa, Y. Aoki,∗1 N. Iwasa,∗2 M. Masuyama,∗1 T. Motobayashi, H. Murakami, A. Taketani,
M. Tanaka,∗3 Y. Togano, and K. Yoneda
In an experiment performed to study the Coulomb
breakup reaction of proton-rich nuclei,1) array of silicon strip detectors (SSDs) is installed between thesecondary target and Superconducting Analyzer for¯¯
MUlti-particle from RAdio Isotope beam (SAMURAI)¯
for identifying the reaction products and measuring
their scattering angles. The strip pitch is determinedon the basis of the accuracy required in the angle measurement. Thus, a total of around 2500 strips are
installed. We are going to employ the Application
Speciﬁc Integrated Circuits (ASIC) technologies in thefront-end circuits of the array to handle the enormous
number of signal channels. The circuit must be able toprovide a dynamic range of 2500 for the identiﬁcationof charged particles from proton to Sn nucleus, whose
atomic number is 50. In order to analyze the pile-up
events of heavy charged particles, wider range is required. We are developing an ASIC so that the frontend circuit can provide a dynamic range of around
10,000. This article reports the speciﬁcations and thepresent status of the development of a prototype ASIC.
This work is supported by the High Energy Accelerator Organization, for the promotion of collaborative
research programs in universities.
The ASIC for a preampliﬁer was fabricated using
a 0.5-µm CMOS process. Figure 1 shows the circuit
diagram of the preampliﬁer in which the techniques
described below are applied to increase the dynamic
range.
Vg~ Qin Chigh / (Chigh + Clow)
Qin

Chigh
Clow

~ Qin Clow / (Chigh + Clow)-A

Fig. 1. A circuit diagram of the preamplifier under development. Qin and Vg represent the input charge from astrip of SSDs and the gate bias voltage, respectively.

In the ﬁrst stage of the circuit, the input charge Qin
is unsymmetrically divided into two channels in proportion to the capacitance ratio between the external
∗1
∗2
∗3

Tokyo Metropolitan College of Industrial Technology
Department of Physics, Tohoku University
Institute of Particle and Nuclear Studies, High Energy Accelerator Organization

coupling condensers Chigh and Clow , as in the case of
Ref.2) . In the present case, the capacitance of the Chigh(= 5.6 nF) is ten times Clow (= 560 pF), as shown in
Table 1. The lower and upper detection limits given in
the table are equal to the magnitude of Qin . For theestimation, we assumed that the single-channel ampliﬁer possesses a dynamic range of 1,000 and the lower
and upper limits are 3.6 fC and 3.6 pC, respectively.
For a system utilyzing the both channels, the range
will be 10,000 and the lower and upper limits will be
4.0 fC and 40 pC. Thus, we can increase the range by
as much as the capacitance ratio by implementing thedual-channel system.
Here, saturation has to be avoided for the upperchannel. The capacitive division of charge does notwork correctly at saturation because the upper channel cannot absorb the divided charge completely forthe case. Useful method to avoid saturatioin is thecompensation of the charge at the input of the ampliﬁer by making use of its charge sensitivity. For thispurpose, an FET has been introduced in the feedback
stage.3) Depending on the saturation voltage of theampliﬁer, the gate bias voltage Vg is adjusted. The
applicability of this method for saturation suppression
has been established only in the case of discrete circuits4,5) and not for in the case of highly integrated
circuit. This novel technique will be examined withthe present ASIC for the ﬁrst time.
In a circuit based on the capacitive division, theopen-loop gain of the ampliﬁer is an important factor.
Its value should be as large as possible, so that thecapacitive division works correctly. We implemented
the cascode connection of the current mirror, as seen
in Ref.6) . A simulation was performed to conﬁrm theincrease in the open-loop gain. The gain was 54 dB fora basic mirror and 82 dB for the cascode connection.
The simulated response of the circuit is shown in
Fig. 2. From Fig. 2(b), which represents the pulse
shape for the upper channel, we can see that the saturation suppression is eﬀective because the maximum
pulse height for each signal is maintained at around a
voltage of -2.1 V, which is below the saturation voltage of around -2.4 V. Steep peaks at the rising edges
in the curves in Figs. 2(c) and 2(d) are due to the ﬁnite rise time of the ampliﬁer. The eﬀect of the peakis removed by a shaping ampliﬁer with an integration
time constant of around 1.0 µS. The simulated pulse
shapes show that each channel is working correctly up
to the upper limit given in Table 1. The measurement, which includes the determination of the upperand lower limits, will be performed after the comple-- 182 -

1

Table 1. Summary of specifications of the preamplifier.
upper channel(a)Chigh = 5.6 nF
4.0 fC
4.0 pC
1,000

coupling capacitancelower limit
upper limit
dynamic range(a) See Fig. 1.

00

(a)

0.66 pC-0.25

lower channel(a)Clow = 560 pF
40 fC
40 pC
1,000

4.0 fC
40 pC
10,000

(b)

0.0

-0.5

-0.5

V (V)

V (V)

-0.75
-1.0

-1.0

-1.25

-1.5

-1.5

-2.0

6.6 pC

-1.75
0.0

0.5

1.0

Time (µs)

1.5

0.0

2.0

(c)

0.66 pC

0.0

6.6 pC

66 pC
0.5

1.0

Time (µs)

0.0

1.5

6.6 pC

2.0

(d)

-0.5

V (V)

-0.25

V (V)

dual channel

-0.5
-0.75

-1.0
-1.5

-1.0

-2.0

6.6 pC

-1.25
0.0

0.5

1.0

Time (µs)

1.5

2.0

-2.5

0.0

0.5

1.0

Time (µs)

66 pC
1.5

Fig. 2. Output signals obtained in the simulation are shown for the upper ((a) and (b)) and lower channels((c) and (d)). In (a) and (c), the input charge varies from 0.66 pC to 6.6 pC, with a step size of
0.66 pC. In (b) and (d), the input charge varies from 6.6 pC to 66 pC, with a step size of 6.6 pC.

tion of the prototype ASIC.
References
1) K. Yoneda et al.: RIKEN Acc. Prog. Rep. 43 (2010).
2) N. Uematsu and S. Nishimura: RIKEN Acc. Prog. Rep.
41 (2008) 151.
3) H. Murakami, private communication.
4) T. Machida, Master thesis of Rikkyo Univ. 2007.
5) Y. Aoki and M. Masuyama, private communication.
6) G.L. Engel et al.: Nucl. Instrum. Meth. in Phys. Res.
A573 (2007) 418.

2

- 183 -

2.0

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Design study of equipment in Rare-RI Ring
Y. Yamaguchi, I. Arai,∗1 T. Fujinawa, N. Fukunishi, A. Goto, T. Kikuchi,∗2 S. Kubono,∗3 T. Moriguchi,∗1
D. Nagae,∗1 T. Ohnishi, T. Ohtsubo,∗4 A. Ozawa,∗1 H. Sakurai, H. Suzuki,∗1 T. Suzuki,∗5 M. Wakasugi,
T. Yamaguchi,∗5 and Y. Yano
We are continuing a design study on each piece ofequipment in the rare-RI ring; the study is based on
the conceptual design of the rare-RI ring1) . The rareRI ring consists of a long injection beam line2) and acyclotron-like storage ring. The cyclotron-like storage
ring, which is a unique device that has features of botha cyclotron and a storage ring, is composed of a septum
magnet, kicker system, RF cavity, and sector magnet.
Because the sector magnet is an especially importantdevice for our project, we mainly report on the design
study of the sector magnet.
To determine the masses of short-lived rare nuclei
with a precision on the order of 10−6 , we will measure the revolution time inside the ring with an accuracy of 10−6 , under the condition that an isochronicity is tuned with a precision of 10−6 in a certain momentum acceptance. The isochronicity of the ring is
obtained by adjusting the magnetic field of each sector magnet. In a first-order γ-factor correction, theisochronous magnetic field is formed by the edge-angleof each sector magnet, which is designed for a fixed
beam energy. An isochronous magnetic field can begenerated with greater precision by using trim coils ineach sector magnet.
To design the sector magnet with such components, a geometrical calculation was performed under the following conditions: edge angle, 8.7◦ in
200 MeV/nucleon; radius of curvature, 4.3 m. Figure 1 shows ideal radial distributions of the strengthof the isochronous magnetic field. This magnetic fieldstrength can be approximated well by a quadratic function of r,B(r)= 1 + 1.3159 × 10−8 r2 ;B0

(1)

here, B0 is the magnetic field strength at the central
orbit. The second component is very small comparedto B0 . This quantity is corrected by using trim coils.
For the sector magnet, two-dimensional field analysis was performed to optimize the geometry of thecoils, iron poles, yokes, and iron shims. The pole gap
was 110 mm, and the magnetomotive force was about
140,000 AT for the main coils. If the main coils areconnected in series, compensation coils are required
for adjusting the field homogeneity with a precision of
∗1

∗2
∗3
∗4
∗5

Institute of Physics, University of Tsukuba
Department of Electrical Engineering, Nagaoka Universityof Technology
Center for Nuclear Study, University of Tokyo
Department of Physics, Niigata University
Department of Physics, Saitama University

Fig. 1. Ideal radial distributions of the strength of theisochronous magnetic field, as determined by performing geometrical calculations.

10−4 for each sector magnet.
On the other hand, it is necessary to arrange thetrim coils in order to efficiently make more precise corrections. To evaluate how the magnetic field can bebrought close to the ideal isochronous magnetic field
by using trim coils, a function was assumed to represent the error in the magnetic field caused by various factors (e.g., gap distortion, edge-angle error, andmultipole components). As a result, it has been understood that the magnetic field can be made to match theisochronous magnetic field with a precision of greaterthan 10−6 by using appropriately arranged trim coils.
Three-dimensional field analysis was performed toevaluate an effective magnetic field length. In our concept, the magnetic field boundary should be same as
the pole edge. As a result, because the influence ofthe leakage magnetic field on a circulating particle isstrong, it is necessary to set up a field clamp or toshorten the pole length. We should consider the variation in the effective magnetic field length depending
upon the radial distributions and the shape of the fieldclamp.
We conclude that there is no technical difficulty inbuilding the sector magnet. However, how to treat thelong-term fluctuations of temperature and current3)
and how to control the long-term stability of the ring,
including the power supply, should still be considered.
We are evaluating the behavior of a particle inside thering by using the developed simulation code4) .
To inject a particle into the ring, we adopt a singleturn injection method with dispersion matching by using both the septum magnet and kicker system. The
particle is bent by about 11◦ when the septum mag-

- 184 -

1

net is used under the present condition. The septum
magnet is divided into two magnets in order to reduce
the load exerted on it. After the particle revolves about1000 times in the equilibrium orbit, it is extracted fromthe ring by using a combination of the same kicker system and other septum magnets. The specification of
the septum magnet for extraction is the same as thatfor injection. Therefore, it is necessary to design two
kinds of septum magnets and one kicker system. Here,
we explain only the important features of their designin this study.
Septum magnets, which are operated as DC magnets, are adjacent to a straight-section vacuum ductof the ring. The leakage magnetic field may affectthe isochronicity of the ring, especially in the case of
the septum magnet located downstream/upstream for
injection/extraction. Three-dimensional field analysis
indicated that it is necessary to take the leakage magnetic field into account when adjusting the isochronicity of the ring because the leakage magnetic field insidethe duct is greater than 10−4 times B0 , even if countermeasures to suppress the leakage magnetic field are
implemented.
The kicker system, which is operated as a pulsed
system, is arranged in a straight section of the ring.
For the kicker magnet, in order to minimize the fieldrise-time, we adopt a distributed twin kicker type system5) . An elementary cell of the magnet consists of a
C-shaped ferrite core and electrodes. The electrodes
and the conductors are made of aluminum. To suppress electrical discharge, the aluminum surface is subjected to electro-polishing. As mentioned above, thiskicker system is used not only for injection but also
for extraction, and hence, a special power supply is required. For efficient injection and extraction, because
the waveforms should be different from each other, twothyratrons must be installed in the power supply. We
believe that a short pulse is suitable for injection anda trapezoidal pulse is suitable for extraction. Therefore, it is necessary to develop different pulse-forming
networks respectively. Recently, we began a feasibility
study on the power supply by using a prototype kicker
system.
As the last piece of equipment, we briefly mention
the RF cavity. It is used to accelerate/decelerate a reference particle of an well-known mass when adjusting
the isochronicity in a certain region of the ring. We
found that the strength of the RF magnetic field6) isless than 10−7 times B0 and that there is no technicaldifficulty in production.
References
1) Y. Yamaguchi et al.: Nucl. Instrum. Methods Phys. Res.
B 266, 4575 (2008).
2) Y. Yamaguchi et al.: RIKEN Accel. Prog. Rep. 41, 137(2007).
3) Y. Yasuda et al.: RIKEN Accel. Prog. Rep. 42, 197

2- 185 -

(2009).
4) H. Suzuki et al.: RIKEN Accel. Prog. Rep. 43, (2010);
I. Arai et al.: Proceedings of STORI’08, 498 (2008).
5) T. Kawakubo: OHO’96.
6) W. Joho: Particle Accelerators 6, 41 (1974).

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Simulation of Particle Trajectories for RIKEN Rare-RI Ring
H. Suzuki∗1 , I. Arai∗1 , T. Fujinawa, N. Fukunishi, A. Goto, T. Kikuchi∗2 , S. Kubono∗3 , T. Moriguchi∗1 , D.
Nagae∗1 , T. Ohnishi, T. Ohtsubo∗4 , A. Ozawa∗1 , H. Sakurai, T. Suzuki∗5 , M. Wakasugi, T. Yamaguchi∗5 , Y.
Yamaguchi, and Y. Yano
Rare-RI Ring1) , which can be used to determine themass of unstable nuclei supplied by BigRIPS2) with a
precision on the order of 10−6 is currently being developped. The mass can be deduced by simply measuring the revolution time (TOF for 1000 turns) andthe velocity (βt ) of even one particle in isochronous
optics. In addition, since its measuring time would beless than 0.5 ms, this new device is suitable for massmeasurements of short-lived rare nuclei, including ther -process nuclei.
This ring, which is 55.710 m in circumference, is aunique device having the features of both cyclotronsand storage rings. It consists of six straight sections(4.782 m) and six sector magnets each with a bending
angle of 60◦ and a diameter of 4.300 m. This device
has a large momentum acceptance (∆P/P ∼ ±1%)
and can be used for measuring the mass of unstable
nuclei supplied as a secondary beam.
The mass of the nuclei is measured as follows. First,
an isochronous magnetic field inside the ring is adjusted with reference to the mass of a particle withknown mass. The isochronous magnetic field is formed
with precise edge angles (β) of each sector magnet andharmonic components (κ) of the magnetic field in theradial direction by using trim coils. Next, the revolution time (TOF for 1000 turns) and velocity βt of aparticle with unknown mass is measured. For a particle with unknown mass, the condition of isochronism is
no longer fulfilled. The mass of the required nuclei canbe deduced from the difference between the TOFs andthe βt values of the reference and this required nuclei.
βt is required because the velocities of these particles
are relativistic.
In order to evaluate the magnetic field, we havedeveloped a simulation program using a fourth-order
Runge-Kutta algorithm in C language3) . The program
includes the following five components: 1) main.c, 2)
Ring.c, 3) ST.c, 4) DM.c, and 5) Eq.c. The program
main.c evaluates the setup parameters for the disired
ring. These parameters are velocity of the beam particle in the central orbit, charge-to-mass ratio of thebeam particle, and correction factors for β and κ. The
program Ring.c controls each element of the ring andrevolves the beam particles 1000 times in their orbits.
The program ST.c represents a straight section, and
∗1

∗2
∗3
∗4
∗5

Institute of Physics, University of Tukuba
Department of Electrical Engineering, Nagaoka Universityof Technology
Center for Nuclear Study, University of Tokyo
Department of Physics, Niigata University
Department of Physics, Saitama University

DM.c, a magnetic sector. The dispersion of the ring is
calculated by Eq.c.
In order to achieve a presicion as high as possible,
which is required for determining of the trajectory ofa beam particle, we perform geometric tracking of thebeam particles in the magnetic sector by assuming thatthe particles revolve in circular orbits within a small
spatial segment. For this purpose, the magnetic sector is divided into 150 subsectors in order to use therectangular (hard-edge) distributions of the magnetic
fields. When divided into 150 subsectors, the calculated TOFs of particles converged. In each subsector,
the magnetic field is represented as a function of radial
direction for harmonic components. The beam trajectory at the exit of a subsector is evaluate from the entrance trajectory by using the Runge-Kutta method.
In the first-order Lorentz-factor correction, we considered the effects of the edge-angle of each sector magnet. When β was set as 8.7◦ , an isochronous magnetic
field was formed with the accuracy of the isochronism
being over 4 × 10−5 , which was determined by performing the simulation. Trim coils are used for further (second-order) tuning by generating the harmoniccomponent of the magnetic field. The required isochronism is achieved with an accuracy of over 1×10−6 withthe harmonic field.
Particle trajectories in the horizontal direction were
calculated as shown in Fig. 1 (up). The trajectories
for 10 turns are shown in this figure. In this simulation, three trajectories of particles having different
momenta, i.e., central momentum, 1% higher than it,
and 1% lower than it, are calculated. The starting positions of these particles at the injection point fulfilled
the condition of dispersion matching. It is observedthat the particles revolving around the ring are stable with a certain dispersion. Figure 1 (down) shows
the trajectories in the vertical direction for 10 turns.
In this figure, all particles have central momentums.
The trajectories for particles with the injection points
at the mid-plane height, 1 cm above it, and 1 cm below it, are shown. Betatron oscillation is seen in thevertical direction.
The emittance for an isochronism with a precition of
10−6 in Rare-RI Ring was also investigated by performing the simulations. Figure 2 shows the emittances for1000 turns when isochronism maintained as functionsof the position and angle at the injection point of thering. From this result, the emittance of isochronism
region with a precision of 10−6 is found to be 40π mm
mrad and 45π mm mrad in the horizontal and vertical- 186 -

1

Trajectories in the horizontal direction

0.05

0.004

0
-0.05

0

100

200
300
Distance [m]4000-0.002-0.006500

Trajectories in the vertical direction>-1*10-6>-2*10-6>-3*10-6
-0.04

-0.02

0
Position [m]Angle [rad]

0
-0.01

0.002
0
-0.002<1*10-6<2*10-6-6<3*10-0.004

-0.02
100

200
300
Distance [m]

400

0.04

0.004

0.01

0

0.02

Emittance in the vertical direction

0.006

+1 cm
0 cm
-1 cm

0.02
Vertical position [m]0.002-0.004-0.1-0.006500

Fig. 1. Particle trajectories (10 turns) in the horizontal direction (up) and the vertical direction (down). The
thin boxes represent the sector magnets for 1 turn. Up
panel: Horizontal direction. In this simulation, three
trajectories of particles that have different momenta arecalculated, i.e., central momentum, 1% higher than it,
and 1% lower than it. The starting positions of theseparticles at the entrance of the ring fulfill the dispersion matching condition. Down panel: Vertical direction. All particles have a central momentum. The trajectories for particles whose injection point is at the
mid-plane height, 1 cm above it, and 1 cm below it are
shown.

directions, respectively, for any momentum of the particle. This emittance is sufficient for the beam transported by the beamline between BigRIPS and Rare-RI
Ring.
The effects of incorrect edge angle or misalignmentof Rare-RI Ring on the isochronism of the ring were
investigated by performing simulations. It was considered that either of these could adversely affect theisochronism of the ring. The limit of misalignment isdetermined on the basis of the TOFs of the particles
with ∆P/P = ±1%, which exceeds that of the particles in the central orbit by 10−6 . A misalignment up
to 2 mm and 6 mm in the radial and azimuthal directions of the ring, respectively, is allowed for eachsector magnet. The rotation of the horizontal plane ofeach magnet is permissible up to 1 mrad. A deviationof β by 0.017◦ is permissible. The loss of isochronism
caused by misalignment can be overcome by further
adjustment of the magnetic field with the trim coils.
A simulation with soft-edge (fringe field) approxi-

2

Emittance in the horizontal direction

0.006

+1%
0%
-1%
Angle [rad]Horizontal position [m]0.1- 187 -

-0.04

-0.02

0
Position [m]

0.02

0.04

Fig. 2. Emittance in horizontal direction (up) and verticaldirection (down) when isochronism of Rare-RI Ring ismaintained. “+” represent the region for isochronism
with a precision of 10−6 . The emittances are 40π mm
mrad and 45π mm mrad in the horizontal and verticaldirections, respectively.

mation of the magnetic distribution is currently being
performed. The shape of the fringe field was obtainedusing the PEP magnet at SLAC4) , which was supplied
as the “default” magnet, using the code COSY Infinity5) developed at Michigan State University. The
emittances for the isochronism with a precision of 10−6
do not change from those calculated using hard-edge
approximation. In order to simulate the particle trajectories more precisely, the fringe shape should be determined by using the TOSCA program.
Rare-RI Ring is currently being designed using thesimulation results. This device is expected to contribute significantly to the study of unstable nuclei
with medium-to-high masses.
References
1) Y. Yamaguchi et al.: Nucl. Instrum. Methods Phys. Res.
B 266, 4575 (2008); Y. Yamaguchi et al.: RIKEN Accel.
Prog. Rep. 43, (2010).
2) T. Kubo: Nucl. Instrum. and Methods Phys. Res. B
204, 97 (2003); T. Kubo et al.: IEEE Trans. Appl.
Supercond. 17, 1069 (2007).
3) I. Arai et al.: Proceedings of STORI’08, 498 (2008).
4) K. L. Brown and J. E. Spencer: IEEE Trans. on Nucl.
Sci., NS-28, 3:2568 (1981).
5) K. Makino and M. Berz: Nucl. Instrum. Methods Phys.
Res. A 427, 338 (1999).

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Second Report on Progress of the Portable Multi-Reﬂection
Time-of-Flight Mass Spectrograph for SLOWRI†
P. Schury,∗1 K. Okada, V. A. Shchepunov.∗2 T. Sonoda, A. Takamine, M. Wada, and H. Wollnik∗3[Mass measurements, unstable nuclei, low energy beam]
We continue the development of a multi-reﬂection
time-of-ﬂight (MRTOF) mass spectrometer for use
with radioactive ion (RI) beams at the future SlowRI
facility. The MRTOF will initially be attached to its
own dedicated gas stopping cell, allowing the systemas-designed to be portable and providing ﬂexibility
in commissioning the device by making it possible touse RI sources wherever available. Three of the main
components for the MRTOF – the ion trap, reﬂection
chamber and ppm-precision bias controller – have been
built; preliminary testing is underway.

these lessons, the new on-line system is expected to beable to achieve very-high resolving powers with a higheﬃciency. High-eﬃciency will result from reducing theemittance of ion pulses extracted from the trap andimproving the vacuum level in the reﬂection chamberby using a sophisticated ion trap. High-resolving power
will result from achieving extremely high-stability voltage supplies for the MRTOF electrodes and also reducing the energy and time spreads of ion pulses extracted
from the ion trap.

Gas Cell
Degraders

RF Multipole
Mass Filter RF Trap
Ion Guide

Injection Side
MirrorMirror #1

Energetic
Radioactive
Ion BeamPower Supplies

Drift Region

Mirror #2

Control Electronics

Ion Detector

Ejection-side
MirrorFig. 1. Planned layout for the portable MRTOF system.

Figure 1 provides a sketch of the system. Energetic ions will be slowed in a solid degrader and thermalized in a helium-ﬁlled chamber. Thermalized ions
are injected into a radio-frequency (RF) multipole ion
beam guide to be transported through a diﬀ erentiallypumped region after being extracted from the gas
cell using a proven RF-carpet technique1) . An RF
quadrupole mass ﬁlter will select for a speciﬁc ion mass
number, removing non-isobaric ions. The isobaric ion
ensemble will then be cooled in a low-pressure gas-ﬁlled
RF ion trap before being injected into the MRTOF.
The system is described in detail previously4,5) .
Lessons learned from an early oﬄine prototype2) include the need to minimize both the emittance of theion pulse and the amount of gas injected into the reﬂection chamber from the ion trap. Additionally, while
the isochronicity of the mirrors is robust, temperaturedependent voltage drifts cause the center-time of theion distribution to drift and make measurements with
low intensity ions diﬃcult. By paying attention to
∗1

∗2
∗3

Tsukuba University, Ibaraki, Japan
SRL, Manchester, England
University of Gießen, Gießen, Germany

Fig. 2. Photograph of the MRTOF reﬂection chamber. The
ion trap will be connected to the obscured ﬂange at the
top of the image. The gas cell will be placed to the leftof the ion trap.

The ion trap and reﬂection chamber for the MRTOF
have been constructed during the past year. Figure
2 shows a photograph of the reﬂection chamber electrodes, support structure and feedthroughs. All reﬂection chamber electrodes are connected to feedthroughs
at the injection side of the reﬂection chamber. This
allows for the vacuum chamber to be removed without
the need to undo any connections, simplifying maintenance and troubleshooting.
Each of the annular electrodes is machined from Titanium and gold-plated on the inside to avoid patcheﬀ ects. The electrodes are isolated from the Titanium
support bracket by a pair of precision ceramic rods, not- 188 -

1

shown. Titanium’s excellent vacuum properties will
enhance the vacuum quality inside the reﬂection chamber; the similarity in thermal expansion coeﬃcients ofTitanium and the ceramic will allow for baking thesystem with minimal worry of dynamic misalignment.
As the total ﬂight length may be as much as 1 km,
the reﬂection chamber must be maintained at ultrahigh vacuum to minimize deleterious eﬀ ects of ionneutral collisions, which would strongly eﬀ ect both thethe eﬃciency of the system and the maximum resolving
power. The reﬂection chamber has been been vacuum
tested using a single 300 l/s turbo-molecular pump,achieving a pressure of 8� 10−9 mbar.
To minimize gas loading of the reﬂection chamberwith buﬀ er gas from the ion trap, the trap makes useof an ejection hole of 200 µm diameter. The trap,
shown in Fig. 3 is built from a pair of printed circuitboards, each consisting of three segmented strip electrodes. An RF signal applied to the outer electrodes
creates a conﬁning quadrupole pseudo-potential. The
strips segmentation allows an axial potential well for
ion trapping. The ions are introduced into the trap
parallel to the electrodes; after cooling, the ions can beejected perpendicular to the trap through a small (r =100 µm) hole in the central electrode. The very low gas
throughput of this geometry should produce very wellcooled ions without deleteriously aﬀ ecting the vacuumin the reﬂection chamber, leading to highly eﬃcient
operation.

extremely stable. To achieve this, a thermally stabilized 24-bit DAC-ADC and voltage monitor system
has been built (Fig. 4). It consists of a large voltage
divider network built from Alpha Electronics’ zero-TC
resistors, a set of ≈1000:1 precision dividers, a 24-bit
ADC, an eﬀ ective 24-bit DAC and a Peltier element
inside a leak-tight plastic box. The DAC monitors
all reﬂection chamber bias voltages via the dividers aswell as the temperature inside the box. Using a digital
PID algorithm, the temperature and all voltages canbe maintained to great precision. The control softwareis still under development. In order to achieve the requisite ppm stability, the PID algorithm will need tomaintain the biases to 4-bits precision in the 24-bit
system, which is perfectly reasonable.

Peltier Element
Precision
Voltage
Divider

ADC-DACcontroller

Zero-TC resistor
divider circuit

Fig. 4. Photograph of temperature controlled 24-bit ADCDAC system. The system is intended to provide stabilization of the bias voltages on the ppm level.

Development work for the portable MRTOF-MS
continues. The MRTOF electrodes and vacuum chamber have been assembled and ultra-high vacuum conditions have been achieved. The ion trap, required toprepare ions for injection into the MRTOF, has beenassembled and testing is underway. A temperature stabilized 24-bit ADC-DAC has been constructed. Usinga voltage-divider network constructed from very low
temperature coeﬃcient resistors, the ADC-DAC system will be the basis for a digital PID loop capable ofmaintaining all MRTOF voltages to δV<1 ppm.
References

Fig. 3. Photograph showing the mounted ion trap. Above
the trap an MCP detector has been placed for testing
purposes. The inset photograph details the printed circuit board used to construct the trap.

In order to achieve the highest possible resolving
power, the mirror electrodes’ bias voltages must be2- 189 -

1) M. Wada et al., Nucl. Instrum. Methods B204, 570(2003)
2) Y. Ishida, M. Wada and H. Wollnik: Nucl. Instrum.
Methods and Phys. Res. B241, 982 (2005).
3) Y. Ishida, M. Wada and H. Wollnik: RIKEN Accel.
Prog. Rep. 40, 150 (2007)
4) P. Schury, et al., Multi-Reﬂection Time-of-Flight Mass
Spectrograph for Short-Lived Radioactive Ions, Proceeding of the 5th Conference on Exotic Nuclei and Atomic
Masses5) P. Schury et al., RIKEN Accel. Prog. Rep. 42, 189(2009)

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Status of the resonance ionization laser ion source at SLOWRI
T. Sonoda, T. Furukawa,∗1 Y. Hirayama,∗2 M. Huyse,∗3 N. Imai,∗2 H. Ishiyama,∗2 S. Jeong,∗2 I. Katayama,∗2
T. Kubo, Yu. Kudryavtsev,∗3 Y. Matsuo, H. Miyatake,∗2 K. Okada,∗4 P. Schury,∗5 T. Shinozuka,∗6
A. Takamine, H. Tomita,∗7 P. Van Duppen,∗3 T. Wakui,∗6 Y. Watanabe,∗2 and M. Wada
A new laser system for the resonance ionization laser
ion source has been installed at SLOWRI facility in
RIBF B1F, as shown in Fig. 1. This system is intended
to be employed in various applications involving theuse of the resonance ionization laser ion source1,2) for
producing pure beams of exotic nuclei.
We proposed a new scheme named Parasitic production of slow RI-beam from a projectile fragment
separator by ion guide Laser Ion Source (PALIS).3–6)
This scheme can be adopted at the SLOWRI facility
to provide low-energy RI beams for the comprehensive
measurement of static properties of thousands of exotic nuclei. Because the expected beam time is very
low in comparison with the demand, PALIS can help
to obtain low-energy RI beams everyday, as long as
the fragment separator BigRIPS is in operation. Most
RI beams produced by projectile fragmentation or inflight fission are abandoned at the first dipole magnet
or in the slits in the first focal plane of the BigRIPS.
A PALIS gas cell located in the vicinity of the first slit
will rescue such RIs by capturing and neutralizing in
high-pressure Ar gas and reionizing by resonance laser
ionization at the exit of the cell. The selectively ionized
RIs can be mass separated by a simple mass separator
and transported to the SLOWRI experimental room.
In addition to PALIS, we plan to realize some more
applications by using the laser system. One application is in-cell/in-gas-jet laser spectroscopy;7,8) the aimof this application is to increase the number of elementsthat can be considered in nuclear laser spectroscopy,
which is so far limited to 50. Another application is the
production of polarized RI beams during ionization.9)
These RI beams will be used in decay spectroscopy
to measure nuclear moments. Another major development is the KEK Isotope Separator System (KISS)
project, which is aimed at synthesizing r-process nuclides with N values around 126. Such exotic nuclei
produced at very low rates can be efficiently collected
and separated to achieve a high purity by using a highpressure gas cell and adopting a resonance laser ionization scheme.
We borrowed many old laser components fromTIARA-JAERI, IRCNMS, and other RIKEN laboratories; these components include two excimer XeCl lasers(Lambda Physik LPX240i) and seven pulsed dye lasers(Lambda Physik FL3001/3002 and Scanmate2E). We
plan to use two-step two-color schemes for the resonance laser ionization of radioactive atoms. The firststep laser excites atoms into an intermediate state. By
using the second-setp laser, the excited atoms are madeto undergo a transition into an auto ionizing state. In
the first-step, we can use UV radiation generated by asecond harmonic generator.
Although the laser components are about 15 years
old and have not been used for eight years, we confirmed that the excimer lasers can fire with reasonable power after comprehensive maintenance. We havealready done first test for the resonance ionization
scheme of Ni atoms by using an off-line reference cell.
We will build a test gas cell with a compact mass separator in order to carry out further off-line tests before
constructing the on-line setups.
We would like to thank the original owners of thelaser components, namely, Dr. Wakasugi of RIKEN,
Dr. Koizumi of JAEA and Dr. Mitsugashira of IRCNMS for their kind support to our projects.
References

Fig. 1. Layout of new laser system at SLOWRI
∗1
∗2
∗3
∗4
∗5
∗6
∗7

Department of Physics, Tokyo Institute and Technology
High Energy Accelerator Research Organization (KEK)
Nuclear Spectroscopy group, IKS, K.U. Leuven (Belgium)
Department of Physics, Sophia University
Department of Physics, Tsukuba University
Cyclotron and Radioisotope Center, Tohoku University
Faculty of Engering, Nagoya University

1) L. Vermeeren et al.: Phys. Rev. Lett. 73 1935(1994).
2) Yu. Kudryavtsev et al.: Nucl. Phys. A 701 465(2002).
3) T. Sonoda et al.: AIP Conf. Proc. 1104 132 (2009).
4) M. Wada et al.: AIP Conf. Proc. 1104 16 (2009).
5) T. Sonoda et al.: RIKEN Accel. Prog. Rep. 42 187(2008).
6) M. Wada et al.: Hyp. Int. (2010) DOI 10.1007/s10751010-0162-y.
7) T. Sonoda et al.: Nucl. Inst. Meth. B 267 2918 (2009).
8) T.E. Cocolios et al.: Phys. Rev. Lett. 103 102501(2009).
9) Y. Matsuo et al.: Phys. Rev. A 77 063404 (2008).

- 190 -

1

RIKEN Accel. Prog. Rep. 43 (2010)

Test report on primary beam dispersion matching at RIBF
S. Itoh,∗1,∗2 H. Baba,∗2 G.P.A. Berg,∗3 N. Fukunishi,∗2 Y. Goto,∗1 T. Hashimoto,∗1 R.S. Hayano,∗1 N. Inabe,∗2
K. Itahashi,∗2 D. Kameda,∗2 P. Kienle,∗4,∗6 T. Kobayashi,∗1 T. Kubo,∗2 K. Kusaka,∗2 K. Miki,∗1 H. Miya,∗5
T. Nishi,∗1 T. Ohnishi,∗2 A. Saito,∗5 K. Suzuki,∗6 H. Tatsuno,∗1 K. Todoroki,∗1 H. Takeda,∗2 and T. Uesaka∗5
for the pionic-atom factory collaboration.
[Pionic-atom, precision spectroscopy, dispersion matching]b16 s11 + b26 s12 + s16 = 0(1)

where bij and sij denote R-matrix elements for the
beam transfer line and the BigRIPS spectrometer (F0F5), respectively. The elements in the matching condition (1) were selected such that b16 = 46 mm/%,
b26 = 0.0 mrad/%, s11 = − 0.69, s12 = 0.0 mm/mrad,and s16 = 32 mm/%. We installed Al degraders in order to measure the dispersion values b16 and s16 . The
measured dispersion values were consistent with theselected values.
∗1
∗2
∗3
∗4
∗5
∗6

Figure 1 shows the histograms of the horizontal position in the F5 focal plane before and after the dispersion matching was applied; the hatched and theunhatched histograms correspond to the position before and after the dispersion matching, respectively.
The position resolution improved by a factor of two
after the dispersion matching was applied. The obtained resolution was 0.83 mm (FWHM), after the
PPAC resolution was subtracted. The resolving powerof the BigRIPS was estimated to be 3860 (FWHM).
The obtained resolving power yields an experimental
resolution of 190 keV (FWHM) for the emitted 3 He at
365 MeV of the (d,3 He) reaction in the deeply boundpionic-atom spectroscopy.
Counts / 0.1 mm

We are planning to perform precision pionic-atom
spectroscopy1) at the RI beam factory (RIBF). The
objective of the experiment is to achieve the highest
ever precision in the deeply bound-pionic-atom spectroscopy by exploiting the (d,3 He) reaction, and thus,
to precisely determine the in-medium isovector interaction strength between the pion and the nucleus. By
applying the dispersion matching technique2) between
the beam transfer line (from the SRC to the target)
and the BigRIPS spectrometer3) (from the target to
the F5 focal plane), we expect to achieve an experimental resolution of 200 keV (FWHM), with which it
is possible to simultaneously observe both the 1s and2s states of the pionic Sn atom. In May 2009, we performed a test experiment to establish a method for realizing the dispersion matching and for measuring theresolution.
We used a 14 N beam with an energy of 250
MeV/nucleon; the beam was provided by the SRC. The
beam energy was chosen such that the beam rigidity
was identical to that of the deuteron beam for use in
the pionic-atom spectroscopy. The beam positions andthe directions in each focal plane were measured by using PPAC4) detectors. The PPAC position resolution
was estimated to be 1.5 mm (FWHM) on the basis of
ray ﬁtting of the incident beam. The beam emittance
was measured to be 39π mm· mrad (FWHM) and 22π
mm· mrad (FWHM) in the F3 achromatic focal plane in
the horizontal and vertical directions, after subtracting
the PPAC resolution.
The dispersion matching condition is described as

3000
2500
2000
1500
1000
500
0
-20

-15

-10

-5
X [mm]

0

5

10

Fig. 1. The histograms of the position in the F5 focal plane
before and after dispersion matching was applied. The
hatched and the unhatched histograms correspond to
the position before and after dispersion matching, respectively.

References
1) K. Itahashi et al., RIBF proposal No.054 (2008).
2) T. Wakasa et al., Nucl. Inst. Meth. A 482, 79 (2002).
3) T. Kubo et al., Nucl. Inst. Meth. B 204, 97 (2003).
4) H. Kumagai et al., Nucl. Inst. Meth. A 470, 562 (2001).

Department of Physics, University of Tokyo
RIKEN Nishina Center, RIKEN
JINA, University of Notre Dame
Technische Universität München
Center for Nuclear Study, University of Tokyo
Stefan Meyer Institute- 191 -

RIKEN Accel. Prog. Rep. 43 (2010)

Performance evaluation of Low-Pressure Multi-Wire Drift Chamber
for RI beam
H. Miya,∗ 1 S. Shimoura,∗ 1 A. Saito∗ 1 K. Miki,∗ 2,∗ 3 M. Sasano,∗ 3 K. Itahashi,∗ 4 S. Itoh,∗ 2,∗ 3 T. Kawabata,∗ 5
M. Nagashima,∗ 6 Y. Shimizu,∗ 3 Y. Shimbara,∗ 6 H. Baba,∗ 4 S. Kawase,∗ 1 H. Kurei,∗ 1 S. Michimasa,∗ 1
K. Nakanishi,∗ 1 S. Noji,∗ 2 S. Ota,∗ 1 Y. Sasamoto,∗ 1 H. Tokieda,∗ 1 K. Yako,∗ 2 T. Uesaka,∗ 1 and H. Sakai∗ 2

� 1
� 2
� 3
� 4
� 5

Center for Nuclear Study, University of Tokyo
Department of Physics, University of Tokyo
Riken Nishina center
Department of Physics, Kyoto University
Department of Physics, Niigata University

about the timing and energy loss was recorded by using
the TDCs.
While the beam passes through the counter gas, � rays are generated because the electrons of the gas are
kicked by the beam. The � -rays trigger the electron
avalanches in the cells through which the beam does
not pass. To avoid incorrect tracking, the � -ray signals
must be discriminated from the beam signals.
In our experiments, pulse widths were obtained from
RPA-130/131; these pulse widths were related to thepulse height of the analog signal3) . Using the obtained
pulse, we can discriminate between the beam signals
and the � -rays on the the basis of the diﬀerence inthe energy loss in these two cases. From the signals
obtained for each layer and trigger event, we selected
the beam signals with the maximum pulse width.

200

103

(a)

150

(b)

102

CountsPulse Width [ns]

250

100

10

50
0
750
800
850
900
950
Leading-edge Timing [ns]

500

1
0

50 100 150 200 250
Leading-edge Timing [ns]

(c)

400
Counsts

We are developing Low-Pressure Multi-Wire Drift
Chambers (LP-MWDCs)1–4) for light radioactive
isotope (RI) beams with an energy of 100–
300 MeV/nucleon. The LP-MWDCs are used in BigRIPS and High-Resolution Beamline (HRBL)5) at RI
Beam Factory.
The LP-MWDCs have three anode layers (x, u, andy). Layer u is tilted at an angle of 30◦ with respect tox. The counter gas used is pure isobutane at a pressureof 10 kPa. By maintaining the gas pressure at a low
value, the eﬀect of multiple scattering can be diminished. Details of the structures and speciﬁ cations of
the LP-MWDCs are provide elsewhere1–4) .
In March, May, and November 2009, the performance of the LP-MWDCs, in which the gas pressure
was 10 kPa and 50 kPa, was evaluated using RI beams
with z = 17, in the commissioning of SHARAQ and
HRBL. We report the position resolutions and tracking eﬃ ciencies for the RI beams as a function of theapplied voltage.
In March and May, the primary beam used was 14 N
with an energy of 250 MeV/nucleon. RI beams of
3
H, 6 He, 9 Li, 10 B, 12 Be, and 11 C were produced bya projectile-fragmentation reaction carried out using
14
N and a primary target of 9 Be. In November, theprimary beam used was 4 He with an energy of 320
MeV/nucleon. RI beams of 3 H and 3 He were producedby the reaction of 4 He with the target. LP-MWDCs
and plastic scintillators were placed in focal planes F3,
F6, F-H7, F-H9, and F-H10 in BigRIPS and HRBL.
The dimensions of the scintillator at F3 were 100 ×
100 mm2 and the scintillator thickness was 1 mm. The
scintillator was used as a trigger counter. The dimensions of the scintillators at F-H7, F-H9, and F-H10
were 220 × 150 mm2 and the thickness was 3 mm.
Details of the experimental setup at each focal plane
is provided in the ref2) .
The anode signals from the LP-MWDCs were readout, ampliﬁ ed, and discriminated by REPIC RPA130/131. The timing of the leading and trailing edges
was recorded by using CAEN V1190A/B multihit
TDCs. The signals read out from the plastic scintillators were ampliﬁ ed and discriminated by IWATSU
Charge to Time Converters (QTCs)7) . Information

300
200
100
0
750

800
850
900
Pulse Width [ns]950

Fig. 1. (a) Relation between pulse width and leading-edge
timing acquired from the wires in one plane (b) spectraof the pulse width and (c) spectra of the leading-edge
timing obtained by selecting the pulse width at 1100 V
and 10 kPa for 14 N.

Figure 1(a) shows the relation between the pulse
width and the leading-edge timing acquired from thewires in the x layer for 14N at 1100 V. Figure 1(b)shows the spectrum of the pulse width in x layer. The
black and red peak denote the signals from the wires
and those with the maximum pulse width selected fromeach trigger event, respectively. The leading-edge tim-

- 192 -

3000
3000
2500
2500
3

H 3H
He6He
Li 9Li
10 10
Be Be
12 12
B B
11 11
C C
14 14
N N

2000
2000

Anode yy Drift length (y)

9

1500
1500

Drift length (u)

1000
1000
500
500

x
Drift length (x)uReasonable beam position

Fig. 2. The geometric conﬁ guration of the planes helps inaccurate position determination.

ing spectrum is shown in Fig. 1(c). The spectra of
the signals with the maximum pulse (red) width showa reasonable drift distribution. The pulse width of
the beam can be discriminated from that of the � -rayson the basis of the correlation between the maximum
pulse width.
In order to estimate the position resolution, the distribution of uu − uxy was investigated. Here, uu is a
hit position in the u layer, and uxy is a hit position
along the u axis and is calculated from the hit positions in layers x and y. The geometric conﬁ gurationof the planes helps in accurate determination of thehit position u (see√Fig. 2.) The position resolution is
given by ∆uu − uxy / 2, where ∆uu − uxy is the full widthhalf maximum of the distribution of uu − uxy . Figure 3
shows the distribution of uu −uxy at 1100 V and 10 kPa
for 14 N. The beam size is 100 mm and 20 mm in thehorizontal and vertical directions, respectively, at thisF-H7 detectors. From the aforementioned distribution,
the position resolution can be estimated.

1600
1400
1200

Counts

1000

FWHM

800
600
400
200
0
-2 -1.5 -1 -0.5

0

0.5

1

Residual R [mm]

1.5

2

00
800
1100
1200
1300
8009009001000
1000
1100
1200
1300
Voltage[V][V]
Voltage(a) 10 kPa(b) 50 kPa

Fig. 4. Position resolution (FWHM) as a function of theapplied voltage at 10 kPa and 50 kPa.

Tracking Efficiency [%]

30

6

1000
1000
900
900
800
800
700
700
600
600
33
H
H
500
500
33
He
He
400
400
300
300
200
200
100
100
00 1700 1800 1900 2000 2100
1700 1800 1900 2000 2100
Voltage [V][V]
Voltage

100
90
80
3
H
70
6
He
9
60
Li
10
Be
50
12
B
40
11
C
14
30
N
20
10
0
800 900 1000 1100 1200 1300
Voltage [V](a) 10 kPa

Tracking Efficiency [%]Anode uPositionm]
Position Resolution
Resolution inin FWHM
FWHM [[µμm]Position Resolution in FWHM [μm]Position Resolution in FWHM [µm]Anode x

100
90
80
70
60
50
40
30
20
10
0

3

H
He

3

1700 1800 1900 2000 2100
Voltage [V](b) 50 kPa

Fig. 5. Tracking eﬃciency as a function of applied voltage
at 10 kPa and 50 kPa.

,at gas pressures of 10 kPa and 50 kPa. Here, σ ofa Gaussian distribution is derived from ∆uu − uxy . Figure 5 shows the tracking eﬃ ciencies as a function of theapplied voltage. The tracking eﬃ ciencies approached
90% for the RI beams at 10 kPa and 50 kPa.
The position resolutions and tracking eﬃ ciencies of
the LP-MWDCs were evaluated as a function of theapplied voltage for the RI beam with z = 1–7 at 10 kPa
and 50 kPa. The position resolutions were 200–300 � m(FWHM) for the beams with z = 2–7 at 10 kPa and200–300 � m (FWHM) for the beams with z = 1–2 at
50 kPa. At 10 kPa and 1100 V, the LP-MWDCs hada dynamic range of z = 3–7. The tracking eﬃ ciencies
reached around 90% for the beams at 10 kPa and 50
kPa.
References

Fig. 3. Residual distribution of uu − uxy at 1100 V and 10
kPa for 14 N.

Figure 4 shows the position resolutions as a function of the applied voltage, evaluated by the abovementioned method at gas pressures of 10 kPa and 50
kPa. The position resolutions were 200–300 � m for the
beam with z = 2–7 at 10 kPa and around 200–300 � m
for the beam with z = 1–2 at 50 kPa. At 1100 V, the
LP-MWDCs had a dynamic range of z = 3–7.
The tracking eﬃ ciency is deﬁ ned as the ratio of thenumber of events satisfying 3σ of the residual distribution to the number of the beams counted by the plastic
scintillator placed the downstream of the LP-MWDCs- 193 -

1) H. Miya et al.: CNS Ann. Rep.2008 49 (2010).
2) A. Saito et al.: RIKEN Prog. Rep. 43 (2010).
A. Saito et al.: CNS Ann. Rep. 2008 47 (2010).
3) K. Miki et al.: CNS Ann. Rep. 2008 51 (2010).
4) T. Yoshida et al.: CNS Ann. Rep. 2008 53 (2010).
5) T. Kawabata et al.: Nucl. Instr. and Meth. B 266 4201
(2008).
6) T. Uesaka et al.: Nucl. Instr. and Meth. B 266 4218
(2008).
7) H. Nishino et al.: Nucl. Instr. and Meth. A 610 710(2009).

RIKEN Accel. Prog. Rep. 43 (2010)

Development of ionization chamber for superheavy elements
K. Ozeki, T. Sumita,∗1 K. Morimoto, K. Morita, and A. Yoneda
In superheavy element laboratory, we have been developing an ionization chamber (IC) to determine Z
and A of superheavy elements. This IC is intended tomeasure the kinetic energy less than 100 keV/nucleon.
The anode electrode is segmented into six strips, which
are labeled 1-6 from upstream to downstream, for the
purpose of the measurement of dE/dx. A detailed configuration of the IC and the voltage applied to eachcomponent of the IC are described in ref. [1].
P10 gas was filled in the IC. Figure 1 shows the energy spectra of α particles emitted by 241 Am obtained
under various pressures. The energy deposits in eachsegmented electrode and the summation of the energy
deposits in each electrode (i.e., 1+2, 1+2+3, · · ·) are
shown. The intrinsic energy spread in the case of an α
particle with an energy of 4.763 MeV is 60 keV (rms).

the calibration constant determined from a previous
α-particle measurement.

Fig. 2. Correlation between estimated and measured energy loss of α particles

Figure 3 shows the correlations between measured
and estimated energy loss when the energy of 11 B is
assumed to be 5.62 MeV and 6.01 MeV. The dashedlines show the correlation determined from α-particle
measurement. Although the correlation determined byassuming the incident energy to be 6.01 MeV has better linearity than that determined by assuming the energy to be 5.62 MeV, the former is inconsistent withthe measured value of total energy loss.

Fig. 1. Energy spectra of α particles.

The energy deposits in each segmented electrodewere estimated using the Stopping and Range of Ions in
Matter code2) . Figure 2 shows the correlation between
estimated and measured energy loss. If the equipotential plane is deformed, dE/dx cannot be measured correctly because a part of ionization electrons escapes toanother electrode than that corresponding to the region in which the electrons are originally ionized. The
good linearity of the correlation between the estimatedand measured energy loss, as shown in Fig. 2, suggeststhat the ionization electrons are collected at the corresponding electrodes by means of a successfully constructed parallel equipotential plane.
The operating characteristics were understood basically by α-particle measurement. Then, kinetic energyof 11 B beam from Pelletron3) was measured. Beamline
parameters were set to extract 11 B of 6.01 MeV; theterminal voltage was 1.50 MV and the charge of 11 B
was varied from 1− to 3+. However, several kinds ofparticles were measured simultaneously; it was thoughtthat these particles have different Z, A, or q. Among
those particles, 11 B3+ -like events were analyzed. The
incident energy was determined as 5.62 MeV by using∗1

Faculty of Science and Technology, Tokyo Univ. of ScienceFig. 3. Correlations between estimated and measured energy loss of 11 B.

Shifts in average ionization energy (W -value) of thegas depending on the nuclide and energy of the incident particle has been reported4) . The discrepancy on
the incident energy measurement from the beamline
setting may be caused by the W -value shift.
Further measurements are planned for heavier elements such as 197 Au. First, it is necessary to characterize the Pelletron and beamline in order to determine
the nuclide and energy of the incident particle.
References
1) K. Ozeki et al.: RIKEN Accel. Prog. Rep. 42 (2009).
2) http://www.srim.org
3) http://www.pelletron.com
4) J. Rodriguez-Cossio et al.: GSI Scientific Report 2000

- 194 -

RIKEN Accel. Prog. Rep. 43 (2010)

Power spectrum detected by ion beam core monitor
H. Watanabe, S. Watanabe,• •1 R. Koyama,• •2 and M. Kase
A nondestructive ion beam core monitor has beendeveloped to measure the intensity of a beam current from2008.1) It is particularly useful if one can continuously
monitor the ion beam current without interrupting the ion
beam. The core monitor has been installed into the RIKEN
Ring Cyclotron (RRC) output beamline to measure ion
beams and background noise. The RRC is driven by the
AVF cyclotron placed upstream of the RRC. The
acceleration RF power supplied for both cyclotron of the
AVF cyclotron and RRC was 14.5 MHz and 29.0 MHz,
respectively. We report here the power spectrum detected by
the ion beam core monitor.
We used a Fast Current Transformer (FCT) manufactured
by BERGOZ Instrumentation. The transformer, model
FCT-082-05:1-H-INS, consists of a toroidal core.
The RRC beam is equivalent to a single-turn coil on the
primary side of the transformer which induces a magnetic
flux in the toroidal core, resulting in an induced current in
the secondary coil. The bandwidth of the FCT is 32 kHz –700 MHz. The fast response of the detector allows us toobserve the higher harmonics of the pulsed beam.
In order for the transformer to measure a current passing
through its center, the wall current imaging the ion beam
must be diverted around the outside of the device. The
beam pipe is electrically isolated by a PEEK sleeve of 4
mm width and the FCT is mounted close to the gap. A
SUS304 box cover forms the FCT electrostatic shielding aswell as the electrical connection between the interrupted
beam pipe outside the FCT. The signal from the FCT is sent
to a low-noise preamplifier. The gain of the preamplifier is
20 dB. The signals obtained from the preamplifier were
measured by a spectrum analyzer.
Since the bunch width of the RRC beam is very short, it
generates many harmonics and the higher order harmonics
have almost the same power as the fundamental one (14.5
MHz), shown in Fig. 1. Then the background noise consists
mostly of 29 MHz signal and its harmonics, shown in Fig. 2.
In Fig. 1, it is clear that the peaks of 14.5 MHz and its odd
number harmonics originated from the ion beam. It isconsidered that the high-frequency noise current originatedfrom RF power of RRC passing through FCT center. In the
future, the noise current will be suppressed by thearrangement of a suitable insulator.• • • •••Reference
1) H. Watanabe, S. Watanabe, R. Koyama, and M. Kase:
RIKEN Accel. Prog. Rep. 42, 139 (2009).
• •1
• •2

Fig.1 Power spectrum of 18O beam of 1.5 euA detected by
the FCT. Many higher order harmonics peaks of the RRC(1f = 29.0 MHz) and the AVF cyclotron (1f = 14.5 MHz =29.0 MHz / 2) were observed.

Fig.2 Power spectrum of background noise at beam off
detected by the FCT. Many higher order harmonics peaks of
the RRC (1f = 29.0 MHz) were observed.• •Center for Nuclear Study, University of Tokyo
SHI Accelerator Service, Ltd- 195 -

RIKEN Accel. Prog. Rep. 43 (2010)

Lithium doped Glass Scintillators for Low Energy Neutron Detection
M. Furukawa,∗1 M. Kurata-Nishimura, H. Otsu, and H. Sakurai
The aim of this work is to test 6 Li-doped glass (6 Liglass) and 7 Li-doped glass scintillators (7 Li-glass) for
low energy neutron detection and γ/neutron discrimination. Neutron detection depends highly on the energy. For high energy neutrons (> 1 MeV), any hydrogenous material (i.e. plastic) can be used to detect
the recoil proton in the (n, p) scattering reaction. For
lower energy neutron (< 1 MeV) neutrons are detected
through the (n, γ) or (n, α) reaction.
The 6 Li-glass is one of the best candidates for the
low energy neutron detector1) because of fast timing response and high cross section for the reaction:n +6 Li → t + α + 4.78MeV. A positive Q-value implies
that very low energy neutrons can be detected. The
only disadvantage is that 6 Li is also sensitive to γ andβ rays. However pulse height discrimination can beutilized to select neutrons from γ-ray background.
1

Experimental Setup and Data Acquisition

In this work, 6 Li- and 7 Li-doped glass scintillator(SAINT-GOBAIN Crystal: GS20 and GS30, respectively) were used. Its composition was SiO2 (57%),
MgO (4%), Al2 O3 (18%), Ce2 O3 (4%) and Li2 O (18%).
The percentage weight of 6 Li in GS20 is 95% and thepercentage weight of 7 Li in GS30 is 99.9%. The Liglass have a diameter of 5cm and thickness of 1cm.
Three species of γ sources (22 Na, 137 Cs and 60 Co)
and a neutron source (252 Cf) were placed in front of
the Li-glass attached to a photomultiplier tube (PMT).
In order to conﬁrm a neutron signal, a 2 cm lead brick
was inserted between the 252 Cf source and the Li-glass.
A signal from the PMT was connected directly to thestorage oscilloscope (Tektronix: 3034B) . A linear ampliﬁer for PMT (10 times gain) was used for low amplitude signals. Waveform data were acquired using
tekXL on excel toolbar through network connection.
Voltages and time information for each triggered event
was stored event by event directly into an excel spread
sheet. An amplitude, a total charge, a charge in the
tail area, rise time and trailing time were evaluatedfrom the waveforms in csv format.
2

Results

Histograms of the amplitude distributions are plotted using 22 Na and 252 Cf in Figs. 1. The pulse
height distributions discriminate between neutron andγ source obviously. It is conformed that the peakaround 0.06V for the 252 Cf is originated from neutrons
by comparing the distributions with and without the∗1

Fig. 1. Histogram of the amplitude distributions of signals
from 6 Li-glass using 22 Na γ source and 252 Cf ﬁssion
source.

Department of Physics, McMaster University, Canada

Fig. 2. Histogram of the amplitude distributions of signals
from 6 Li-glass using 252 Cf with and without a 2 cm
lead brick. The lead brick absorbs γ rays lowering γ
ray counts and increasing neutron counts.

lead brick between the source and the detector as isshown in Figs. 2. Rising times were also calculated foran estimation of the time resolution and pulse shapediscrimination. It is found that the typical rise time
for neutron signal is less than 5 ns. Thus we can expect
the suﬃcient time resolution for the neutron detection
using 6 Li-glass. For the pulse shape discrimination,
further investigation is needed.
3

Conclusion

In this work, 6 Li- and 7 Li-doped glass were tested
for a neutron detector. The waveforms were measured
by the oscilloscope and recorded event by event automatically. By analyzing the waveform with a diﬀ erent
aspects, separation of neutron from γ was studied. The
pulse height distributions discriminate between neutron and γ source obviously for 6 Li-glass while no clear
diﬀ erence is observed for 7 Li-glass. It is expected that6
Li-glass can provide a suﬃcient time resolution for
the neutron detection.
At the end, we would like to express special thanks
to Prof. Shimoda in Osaka University, who kindly provides us the 6 Li- and 7 Li-doped glass scintillator forthis work.
References
1) S. Schwarz, L. G. Strömberg and A. Bergström: Nucl.
Phys. 63 593 (1965)- 196 -

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Pulse structure dependence of the proton polarization rate
T. Kawahara,∗1 T. Uesaka,∗2 Y. Shimizu, S. Sakaguchi and T. Wakui,∗4
A polarized solid proton target for RI beam experiments has been developed at the Center for Nuclear
Study, University of Tokyo1) . Protons are polarizedthrough the transfer of the electron population diﬀerence in the photoexcited triplet states of pentacene4) .
By using this method, proton polarization of approximately 20% has been achieved at a low magnetic ﬁeldof 0.1 T and at high temperatures of 100 K. Although
this target has been successfully used in RI beam experiments2,3) , further improvement of proton polarization is desirable for future applications. To enhance
the photoexcitation power, we examined the pulsestructure dependence of the proton polarization rate.
For the optical excitation of pentacene molecules,
an Ar ion laser (Coherent TSM25) with a wavelength
range from 454.5 nm to 528.7 nm and a total maximum
output power of 25 W is used. Since this laser is acontinuous wave (CW) laser, light can be mechanicallypulsed by using an optical chopper (Fig. 1). The duty
factor can be easily varied by adjusting the degree ofthe overlap of two chopper blades. The frequency ofthe laser pulse can be changed by changing the rotating
speed of the optical chopper.

2 chopper blades

slitsFig. 2. Time chart of polarization. When the crystal is irradiated by the laser, the electron polarization occurs.
Immediately after laser irradiation, microwave irradiation is eﬀected, and the magnetic ﬁeld strength is swept
in order to transfer the electron polarization to the protons.

frequency. The magnitude of proton polarization after
a 5-min buildup is deﬁned as the proton polarization
rate, which is measured by the pulsed NMR method.
The results are shown in Fig. 3, where the proton
polarization rate is plotted as a function of repetition
frequency.

Fig. 1. Optical chopper bladesWith the help of this optical system,we can change
the duty factor from 5% to 50% and the repetition
frequency from 0.75 to 10.5 kHz. The pulse width isdetermined from the duty factor and repetition frequency. These three parameters are related as
D = f t,(1)

where D, f , and t are the duty factor, repetition frequency, and pulse width, respectively.
Measurements were carried out under the following
conditions. The crystal used was 14 mm in diameter and 3 mm in thickness. Protons were polarized at
200 K in a magnetic ﬁeld of approximately 60 mT.
Figure 2 shows a typical time chart of the polarization
process. This process is repeated at a certain repetition
∗1

∗2
∗3

Department of Physics, Toho University
Center for Nuclear Study, Graduate School of Science, University of Tokyo
Cyclotron and Radioisotope Center, Tohoku University

Fig. 3. Polarization rate measured by changing the duty
factor and repetition frequency.

In a previous study1) , the repetition frequency andduty factor were reported to be 2.5 kHz and 5%, respectively. The measured data are normalized by theprevious data. At high frequency limits, the polarization rate is almost saturated and is proportional tothe duty factor. In the present study, we found thatthe proton polarization rate takes the maximum value
when the repetition frequency is 10.5 kHz and the duty
factor is 50%. The polarization rate is improved by afactor of 5 as compared to that reported previously.
To estimate the polarization rate, we built a simple
theoretical model of electron population. The polar-- 197 -

1

ization process involves three steps: electron polarization, polarization transfer from electrons to protons,
and relaxation of electron polarization. In this model,
we assume that the eﬃciency of the polarization transfer from electrons to protons is 100%. Electron polarization is the electron population diﬀerence between
the m = 0 and m =−1 states, which are the magnetic
substates of the triplet state of pentacene.
In the ﬁrst step, the electron population increases
according to the buildup function during laser irradiation. The buildup function is given ast
fb,i (t) = Ai τi {1 − exp(− )},τi(2)where τi is the lifetime of the triplet state, A is the
population rate and i is the magnetic substate of thetriplet state. After laser irradiation, the electron population diﬀerence is transferred to the protons, andthe electron population decreases according to the relaxation function. When the electron polarization istransferred, the number of electrons in the two magnetic substates is reversed by cross polarization3) . The
relaxation function is given ast
fr,i (t) = exp(− ).
τiresult and the present calculation. In Ref. 4, the lifetimes at 100 K are τ0 =26 µsec and τ− =83 µsec. The
lifetimes observed at 200 K are almost the same as
those at 100 K. The proton polarization rate calculated by our simple model reproduces the measured
data as shown in Fig. 5.

(3)Here, the lifetimes of the two substates used in themodel are considered as free parameters.
The solid and dotted lines in Fig. 4 represent thetime development of the electron population in the m= 0 and m = −1 states, respectively.

Fig. 5. Polarization rate calculated from our simple model(solid curves) and the measured polarization rate. The
rates are calculated for duty factors of 5%, 10%, 15%,20%, and 50%.

We have examined the pulse-structure dependenceof proton polarization rate. We found that the proton
polarization rate depends strongly on the pulse structure. At a duty factor of 50% and repetition frequency
10.5 kHz, the polarization rate is improved by a factor of 5. The pulse-width dependences are reproducedwith a simple model, by assuming the life time of thetriplet state at 200 K to be τ0 = 26 µsec and τ− =83µsec. These values are almost equal to those measured at 100 K.
References
1) T. Wakui et al., Nucl. Instr. Meth. A 550 (2005) 521.
2) M. Hatano et al., Eur. Phys. J. A 25 (2005) 255.
3) S. Sakaguchi et al. Proceedings of ISPUN07, World Scientiﬁc (2009) 245.
4) M. Iinuma. Ph. D thesis, Kyoto University, (1997).

Fig. 4. Time development of electron polarization.

ρ0 and ρ− , the electron populations in the m = 0
and m = −1 states,respectively, are calculated by using
equations (2) and (3). The proton polarization rate isderived asdPp∝ ρ0 − ρ− .
dt

(4)The lifetimes τ0 and τ− are determined to be 26 µsec
and 88 µsec, respectively, by using the measurement2- 198 -

RIKEN Accel. Prog. Rep. 43 (2010)

New method of pulse shape analysis
for segmented Ge detectors by using moments
S. Go,∗1 S. Shimoura,∗1 E. Ideguchi,∗1 S. Ota,∗1 H. Miya,∗1 H. Baba∗2
We have been developing a position-sensitive Ge detector array, CNS GRAPE (Gamma-Ray detector Array with Position and Energy sensitivity). The arrayconsists of 18 detectors, each of which contains twoplaner Ge crystals with an effective radius of 30 mm
and thickness of 20 mm. Each detector has a common
anode between two crystals and two 3 × 3 cathodes.
Fig. 1 shows the definition of the coordinates. Theinteraction point of the γ-ray can be deduced by pulse
shape analysis. Our group has developed a method for
position extraction by using the analog pulse shapetechnique1,3) .

Fig. 2. DSP system consisting of two 9-ch ADCs and ourdaughter modules (TechnoAP, APU7110-A40) .

digitized time. The first-order moment corresponds tothe average of the pulse shape; the second to the RMS;
the third to the skewness.
Fig. 3 demonstrates the correlation between thefirst moments from the measured data recorded by
DSP. This dependence is result obtained using the analog pulse shape technique, where the z-value of thehit position can be extracted from the ordinate andabscissa3) .

Fig. 1. Schematic view of detector.

In 2008, we started to upgrade the system by digital
signal processing (DSP), where the outputs from thepreamplifier are digitized by a 100-MHz flash ADC andprocessed by digital filtering methods such as trapezoidal shaping and constant-fraction time pick-off (Fig.
2).
In order to use the DSP system for position extraction, we are attempting to develop a simple algorithm for the digitized data. The moments of thedigitized signals are introduced as candidates for developing such an algorithm2) . The n-th moment of thesignal is expressed as
tn =

Σi tni × f (ti )dQ(ti ), f (ti ) =,Σi f (ti )dt(1)where Q(ti ) denotes the digitized data obtained fromthe charge sensitive preamplifier, and ti denotes the∗1∗2

Center for Nuclear Physics, University of Tokyo
RIKEN Nishina center

Fig. 3. Correlation between first moments, using a 22 Na
source. The event near the cathode is selected whenthe moments are calculated.

In order to extract three-dimensional-position, detailed comparison of the pulse shapes and pulse simulation are important. The time evolution of induced
charge signals on cathodes, pulse shapes, can be simulated by calculating the three-dimensional electric po-- 199 -

tential and by using the weighting potential proposedin the Schokley-Ramo theorem4) . Fig. 4 shows anexample of the calculated weighting potential. On thebasis of this theorem, the time evolution of the induced
charge Q(ti ) is expressed as follows:

Fig. 4. Calculated weighting potential. In this case, a voltage of 1[V] is applied to the center electrode, and a
voltage of 0[V] is applied to the boundary.

Q(ti ) = n0 e(φw (Xh (ti ), Yh (ti ), Zh (ti ))− φw (Xe (ti ), Ye (ti ), Ze (ti )),(2)

where n0 denotes the number of carriers, and e isthe elementary charge. The position of the carriers (electrons and holes) at time ti is denoted by(X(ti ), Y (ti ), Z(ti )), which is determined by the distribution of the static electric field, mobilities, and diffusion constants. φw is the weighting potential. Figure
5 shows the preliminary results obtained by assumingthat the electron and hole move in the z-direction withconstant velocities; in this case, the hit positions are(0, 0, 5mm) and (0, 0, 15mm).

Fig. 5. Simulated charge signal induced in the cathode.
The dashed curve shows the contribution of the holes
and electrons. In this case, the γ-ray interacts at (0, 0,5mm) and (0, 0, 15mm). The pulse heights are normalized to 1.

First, the extraction of the z-position will be carriedout by using the correlation between the first momentsfrom the simulated pulses. Extraction of the x- and ypositions will also be carried out using the simulated

2- 200 -

pulse shapes of the non-hit segments. These extraction
are currently underway.
References
1) S. Shimoura : Nucl. Instr. and Meth. A 525, 188 (2004).
2) S. Go: Am. Phys. Soc. Vol 54, 10, 119 (2009).
3) M. Kurokawa: IEEE 50 1309 (2003).
4) Z. He: Nucl. Instr and Meth. A 463 250 (2001).

RIKEN Accel. Prog. Rep. 43 (2010)

PHENIX silicon vertex tracker projectY. Akiba, S. Baumgart, N. Cassano,∗1 S. Chollet,∗2 V. Cianciolo,∗3 A. Deshpande,∗1,∗4 O. Drapier,∗2
A. Drees,∗1 H. En’yo, K. Fujiwara,∗5 F. Gastaldi,∗2 Y. Haki,∗6 K. Hashimoto,∗6 R. Ichimiya, J. Kanaya,
M. Kasai,∗6 K. Kurita,∗6 M. Kurosawa, A. Lebedev,∗7 E. J. Mannel,∗8 R. Nouicer,∗9 C. Ogilvie,∗7 Y. Onuki,
R. Pak,∗9 C. Pancake,∗1 P. Riedler,∗10 E. Shafto,∗1 M. Sekimoto,∗11 W. Sondheim,∗12 M. Togawa, A. Taketani,and the PHENIX VTX group• The second annual review of VTX was held at
BNL in June 2009.
• The Q/A of the pixel sensor module is ongoing.
• The assembly of the pixel ladders is ongoing.2)• An electronic checking system for pixel ladders isdeveloped.3)• The production of pixel staves (mechanical support + cooling) has been completed at LBNL.
• The production of pixel read-out boards (SPRIO)
has been completed at Ecole Polytechnique.
• The production of pixel front-end-module (FEM)
has been completed at Stony Brook University.
• Test bench system of pixel ladders has been developed.4) One set of the system is installed at BNL.
• The Q/A of the strip sensors has been complete.
• The production of strip read-out card (ROC) is
ongoing and to be completed soon.
• The assembly of strip silicon modules is ongoing.
• The first strip ladder has been assembled.
• The development of the read-out electronics chain
for the strip system is nearing completion at
ORNL. The production of the RCC boards is ongoing. The production of the LDTB boards, thestrip buses, DIB, and CIB will start soon.
• The design of the mechanical support system andcooling of the VTX has been completed.
• The abrication of mechanical support system of
VTX is ongoing at LBNL and will be completedsoon.
• On the software side the physics simulation of
VTX?) is ongoing.

We are constructing a silicon vertex tracker (VTX)
for the PHENIX experiment at RHIC. The primary
purpose of the detector is to carry out precise measurements of heavy-quark (charm and beauty quarks)
production in A + A, p(d) + A, and polarized p + p
collisions. The main physics topics addressed by the
VTX are as follows.
• Probing high-density partonic matter◦ Energy loss of heavy quarks (charm and bottom quarks) in dense matter◦ Elliptic flow of heavy quarks in dense matter◦ Open heavy-quark production◦ Medium induced modification of jets

• Measurement of the gluon spin polarization∆G(x) of the nucleon◦ ∆G(x) with heavy-quark production◦ ∆G(x) with γ-jet measurement• Nucleon structure in nuclei◦ Gluon shadowing over a broad x range

These are key measurements that are required for future RHIC programs, both for the study of Quark
Gluon Plasma (QGP) in heavy-ion collisions and forthe measurement of the nucleon spin-structure functions.
The VTX detector consists of two inner layers of silicon pixel detectors1) and two outer layers of silicon
strip detectors. The detector covers |η| < 1.2 in pseudorapidity and ∆φ ≈ 2π in azimuth. The project isfunded by RIKEN, the US DOE, and Ecole Polytechnique. The US side of the project commerced in US
FY2007. The total budget is 4.7 M US dollars overfour years (FY2007-FY2010).
The significant developments made this year are as
follows.

References∗1

Stony Brook University, USA
LLR, Ecole Polytechnique, CNRS-IN2P3, France∗3 Oak Ride National Laboratory, USA∗4 RIKEN BNL Research Center, USA∗5 Tokyo Metropolitan Industrial Technology Research Institute, Japan∗6 Rikkyo University, Japan∗7 Iowa State University, USA∗8 Columbia University, USA∗9 Brookhaven National Laboratory, USA∗10 European Organization for Nuclear Research, Switzerland∗11 High Energy Accelerator Research Organization, Japan∗12 Los Alamos National Laboratory, USA∗2- 201 -

1) A. Taketani et al.: RIKEN Accel. Prog. Rep. 43, 202(2010).
2) M. Kurosawa et al.: RIKEN Accel. Prog. Rep. 43, 208(2010).
3) Y. Haki et al.: RIKEN Accel. Prog. Rep. 43, 206(2010).
4) M. Kasai et al.: RIKEN Accel. Prog. Rep. 43, 204(2010).

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Silicon Pixel Detector for PHENIX Vertex Tracker†
A. Taketani, Y. Akiba, N. Apdula,∗1 S. Baumgart, C. Biggs,∗2 S. Chollet,∗3 O. Drapier,∗3 A. Dress,∗1 H. En’yo,
K. Fujiwara,∗4 F. Gastaldi,∗3 Y. Haki,∗5 K. Hashimoto,∗5 R. Ichimiya, Y. Ikegami, J. Kanaya, M. Kasai,∗5
T. Kobayashi,∗4 T. Kondo,∗4 K. Kurita,∗5 M. Kurosawa, J. LaBounty,∗2 E. J. Mannel,∗6 Y. Nomiya,
R. Nouicer, H. Ohnishi, Y. Onuki, R. Pak,∗2 C. Pancake,∗1 P. Riedler,∗7 M. Sekimoto,∗8 E. Shafto,∗1
S. Shimoda, W. Sondheim,∗9 M. Togawa, S. Watanabe,∗10 Y. Yamada, and the PHENIX VTX group
PHENIX experiment at Relativistic Heavy Ion Collider (RHIC) will be upgraded with a silicon vertex
tracker (VTX) in 2010. It will enhance physics capability in both spin and heavy-ion programs. The VTX
covers | η |≤ 1.2 and ∆φ ∼ 2π with four layers of silicon sensors.1) It will be installed 2.5 cm away from thebeam line, which is located just outside with a radiusof 2 cm beam pipe. The VTX can be used to deteremine whether heavy quarks or light quarks are porduced;
this is possible since the VTX can track a displaced vertex corresspoinding to the long-lived charm and bottom mesons, whose cτ values are in the range of 100
to 400 µm. Further, the jet can can be determined bymeasuring the momentum of the charged track within
its large acceptance of the VTX.
In the VTX, ypixel detectors are located on the two
inner layers and stripixel detectors2) are located on thetwo outer layers. We, the RIKEN group, are in chargeof 30 pixel ladders, which is the smallest replaceable
unit in the detector. This article describes the progressof the pixel ladders.
A pixel ladder consists of four sensor hybrids, a support stave, and two readout buses. The pixel size ofthe sensor is 50 × 425 µm2 . One sensor has 256×32×4
pixels and is connected to four ALICELHCB1 chips by
bump bonding. Signals from the sensor are converted
to binary hit pattern data by using a preamplifier anda discriminator. These binary data are transmitted asdigital signals to a silicon pixel readout (SPIRO) board
via a pixel bus and an extender. The SPIRO board
multiplexes data from eight ALICELHCB1 chips andtransmits the data to a front end module (FEM) thorough 1.6 Gbps serial optical links.
The process of gluing the sensor hybrids, support
stave, and readout buses in the ladder fabrication were
improved; glue was dispensed by using a metal and apaddle instead of dispensing robot3) in the previous
years. The gaps between the hybrids and stave were
carefully adjusted manually under a microscope during

the stacking process.
After the gluing process, the hybrids and readoutbuses were connected by wire bonding. In the initialstage test fabrication of the pixel ladder, a wire shorted
bewteen a bonding pad and the guard ring surrounding
the pad; hence the signal could not be transmitted.
Since it was not easy to visually detect the short. awire-bonding checker was developed.4) The checker canbe used to measure the resistance between the pad, andthe guard ring which is connected to the the ground.
When a short to the ground is detected, the associatedwires are replaced.
We fabricated two pixel ladders as production version by the following improved gluing procedure. The
ladders wer electrically tested by performing charge
injection tests, β-ray irradiation tests, and cosmic-ray
tests by using SPIRO and FEM. Their functinallity of
the ladders was confirmed.5)
The ladders were operated in 0◦ C environment. A
test bench box with a cooling system was developed.
An interlock system that helps to prevent any accidental damage to the ladders destruction of ladders by
accicidents was developed.6) The temparature and flowrate of the cooling liquid were monitored. Further, thehumidity of the test bench box, which is filled with
dry N2 gas was measured. If these monitored values
deviate from a specific value, the interlock system will
shut off power supply to the ladder or close the valve
for the cooling liquid.
In summary, we developed some tools for fabarication quality assurance (QA) and ladder-funcationality
QA processes. The fabrication of PHENIX pixel ladders has been commenced. They will be installed andwill start opeartion in 2010.

∗1

Stony Brook University, USA
Brookhaven National Laboratory, USA∗3 LLR, Ecole Polytechnique, CNRS-IN2P3, France∗4 Tokyo Metropolitan Industrial Technology Research Institute, Japan∗5 Rikkyo University, Japan∗6 Columbia University, USA∗7 European Organization for Nuclear Research, Switzerland∗8 High Energy Accelerator Research Organization, Japan∗9 Los Alamos National Laboratory, USA∗10 Tokyo Metropolitan College of Industrial Technology, Japan∗2

Fig. 1. Assembled pixel ladder, Top: Dummy assembly before gluing. Cneter: Dummy after gluing. Bottom:
Fully assembled and functional ladder- 202 -

1

References
1) Y.Akiba et al.: RIKEN Accel. Prog. Rep. 43, 201 (2010)
2) Z.Lee et al.: Nucl. Instr. Meth. A 466, 366 (2001)
3) A.Taketani et al.: RIKEN Accel. Prog. Rep. 42, 203(2009)
4) Y.Haki et al.: RIKEN Accel. Prog. Rep. 43, 206 (2010)5) M.Kurosawa et al.: RIKEN Accel. Prog. Rep. 43, 208(2010)
6) M.Kasai et al.: RIKEN Accel. Prog. Rep. 43 ,204 (2010)2- 203 -

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

QA test bench for the PHENIX silicon pixel detector
M. Kasai,∗1 A. Taketani, C. Biggs,∗2 C. Pancake,∗3 E. Mannel,∗4 E. Shafto,∗3 H. En’yo, J. LaBounty,∗2
J. Kanaya, K. Kurita,∗1 K. Hashimoto,∗1 K. Fujiwara,∗5 M. Kurosawa, M. Togawa, M. Sekimoto,∗6
N. Apadula,∗3 R. Nouicer,∗2 R. Ichimiya, S. Baumgart, S. Shimoda,∗7 Y. Akiba, Y. Nomiya,∗7 Y. Onuki,
Y. Haki,∗1 Y. Ikegami,∗7 Y. Yamada∗7 and PHENIX VTX group.
A Silicon Vertex Tracker (VTX) will be installed for
PHENIX experiment at RHIC in 2010. The VTX will
enhance the physics capabilities of the PHENIX central arm spectrometers by providing precision measurements of heavy-quark (charm and beauty) production
in A+A, p(d)+A and polarized p+p collisions.
The VTX consists of pixel detectors at inner 2 layers (10 ladders and 20 ladders ) and strip detectors
at outer 2 layers, which cover pseudo-rapidity of |η|≤1.2, and φ ∼2π in azimuth. Japanese group including Rikkyo university, RIKEN and KEK is responsible
for the pixel ladders.
We have started a mass production of the pixel ladder1)2)3) since last year. The assembled ladders haveto go through quality assurance(QA) test at RIKEN
and BNL. During QA test, there are possibilities of aserious damage for example, the glued parts of eachmaterial peel off and the coolant builds up condensation on the surface of the ladder, and so on. So wemade an interlock system on the ladder test bench inorder to prevent the serious damage on the ladder andto be within an acceptable level. In this report, we describe the interlock system for construction of ladder
QA test bench.
Figure 1 shows a schematic view of QA test bench forthe pixel ladder. The ladder was connected to a Silicon
Pixel Interface Read Out (SPIRO) board which controls read-out chips and collects data and sends themto the FEM (Front End Module) via optical cables.
The ladder is confined in a bench box filled with dry
nitrogen gas. NOVEC, which is cooled to 0◦ C by achiller to improve the resistance to radiation, flows into
the ladder, and returns to the chiller through a control
box. The control box is connected with three power
supplies (High Voltage for sensor bias, Low Voltage forladder, SPIRO4) ) to operate the ladder. And pixel silicon sensor needs a reverse bias voltage (50V) to makeit depleted. Low voltage (3.5V) is for operating readout chips.
The bench box is made to be as compact as possible, and is attached by the connectors for NOVEC
and nitrogen gas as shown Figure 2. A hygrometer isplaced to a center of the bench box. In order to main∗1
∗2
∗3
∗4
∗5
∗6
∗7

Department of Physics, Rikkyo University
Brookhaven National Laboratory
Stony Brook University, USA
Nevis Labs Columbia University, USA
Tokyo Metropolitan Industrial Technology Research Institute.
KEK
Advanced Technology Support Center in RIKEN

tain air tightness of the test bench, extenders (Flexible
printed circuits) are pressed by the silicon rubbers. In
order to test the hermetic seal of the box, dry nitrogengas whose humidity is 0% flowed into it at the rate of
0.03L/min. Then humidity in the box is maintained
at 1.0%.

Fig. 1. A schematic view of ladder QA test bench.

Fig. 2. A bench box with NOVEC and nitrogen gas connectors.

Figure 3 shows a front and rear panel side of
the control box. A thermometer and temperature
controller, a humidity controller, a flow meter and asolenoid valve are installed. We can monitor these values and set their thresholds.

- 204 -

• H [%] : Humidity in the bench box• T [◦ C] : Temperature of NOVEC (outlet from the1

ladder)• F [L/min] : Flow rate of NOVEC (outlet from theladder)
The LED indicators display the status of the each interlock monitors. Green shows normal, and red shows
the cause of the interlock.

Fig. 4. Ladder QA test bench at BNL

References
1) Y. Onuki et al.: NIM A 606(2009)395-403 (2009)2) M. Kurosawa: RIKEN Accel. Prog. Rep. 43, 208 (2010)
3) Y. Haki: RIKEN Accel. Prog. Rep. 43, 206 (2010)4) R. Ichimiya: RIKEN Accel. Prog. Rep. 41, 171 (2007)

Fig. 3. A control box for the interlock system.

We set these threshold conditions on the controlbox.
(1) H is lower than 5%.
(2) T is lower than 5◦ C.
(3) F is higer than 0.5L/min.
Before we start ladder QA test, firstly a power supplyof the control box is turned on. Secondly, we flow dry
nitrogen gas into the bench box. Thirdly, the chiller
is operated at 0◦ C after H is lower than 5%. Finally,
three power supplies are turned on and the ladder canwork for QA test. If even one of the condition is notsatisfied, the interlock system works and the prohibition signal is sent to all power supplies.
Now the test bench including the interlock system
for ladder QA test has been completed and settled at
BNL as shown in Figure 5. We confirmed that the interlock system operated correctly. We built a second
test bench for RIKEN. Ladder QA test can be performed at RIKEN and BNL.

2

- 205 -

RIKEN Accel. Prog. Rep. 43 (2010)

Development of wire bonding electrical-short checker
for silicon pixel ladder in the PHENIX vertex tracker
Y. Haki∗1 , M. Kurosawa, Y. Akiba, S. Baumgart, H. En’yo, K. Fujiwara∗2 , A. Taketani, K. Hashimoto∗1 ,R. Ichimiya, K. Kurita∗1 , M. Kasai∗1 , J. Kanaya, Y. Onuki, C. Pancake∗3 , M. Sekimoto∗4 , E. Shafto∗3 ,M. Togawa and the PHENIX VTX group
The PHENIX detector at RHIC-BNL will be upgraded with a silicon vertex tracker (VTX) surrounding a beam pipe with four cylindrical layers1) . The
inner two layers include silicon pixel detectors (SPDs),
and the outer two layers include silicon strip detectors.
The RIKEN-Rikkyo group is currently developing an
SPD as part of the PHENIX VTX upgrade. The SPD
is made up of 30 assembly units called ladders, eachof which consists of a thermal plate, four sensor hybrids, and two pixel buses2) . A sensor hybrid is an assembly of a silicon pixel sensor and four readout chips(ALICE1LHCb), which are bonded to the sensor via
bumps with a diameter of 20 µm. The readout chip has
8192 pixel cells arranged in 32 columns and 256 rows.
The pixel size is 50 µm × 425 µm. The pixel bus is acopper-aluminum-polyimide base flexible printed circuit board. The signals from the silicon pixel sensor
are read out through the readout chip and pixel bus,which are electrically connected by wire bonding, asshown in Fig. 1.

Fig. 2. Pattern diagram and closeup image for the region
around the bonding pads of the readout chip.

A setup of the WBC is shown in Fig. 3. A half-ladderis connected to a switch system (7002 SWITCH SYSTEM) with a flexible printed circuit board (pixel bus
and bus extender3) ) and a test card. The switch system changes the signal lines of the pixel bus, whose
resistance is known. A digital multimeter (2000 MULTIMETER) measures the resistance between a signal
line of the pixel bus and the guard ring (ground layer).
A Visual Basic program controls the switch system andthe digital multimeter via GPIB-to-USB interface (NIGPIB-USB-HS) in the Windows XP environment.

Fig. 1. Ladder cross section.

A pattern diagram and closeup image around thebonding pads of readout chip are shown in Fig. 2. A
guard ring is located at top of the bonding pads. Sometimes, dust particles introduced during the quality assurance (QA) process performed hybrid sensor are retained on the bonding pad. Electrical short occurs if
a wire is bonded to a dust-covered bonding pad and aguard ring. This electrical short causes failure of datatransmission from the ladder. Therefore, an electricalshort checker must be used during the production of
the ladder. Thus, we have developed a wire-bonding
short checker (WBC) for the silicon pixel ladder.
∗1

∗2
∗3
∗4

Department of Physics, Rikkyo University
Tokyo Metropolitan Industry Technology Resrach InstituteDepartment of Physics and Astronomy, Stony Brook University,USA
Institute of Particle and Nuclear Studies, KEK

Fig. 3. Setup of wire-bonding short check system.

In the QA procedure, the criterion to be satisfied
for the electrical short is that the resistance between asignal line of the pixel bus and the ground layer shouldbe less than 100 Ω. This is because the average resistance value of a signal line of pixel bus is 40 Ω. The
test voltage of the multimeter becomes as high as 10
V during high-resistance measurements under normal
conditions. The dielectric withstanding voltage of acapacitor on the pixel bus is 6.3 V. In order to reduce
the test voltage, a protection zener diode is added tothe connection box. A characteristic curve obtained
the zener diode and a circuit diagram of the connection box are shown in Fig. 4. If the test voltage exceeds
the breakdown voltage (2.5 V in the present case), thecurrent i2 increases. Threfore, the voltage applied tothe capacitor on the pixel bus is controlled to be lessthan 2.5 V.

- 206 -

Fig. 4. A characteristic curve obtained for the zener diodeand a circuit diagram of the connection box.

The switching rate of the switch system is 2 Hz, which
is determined by the digital multimeter response rate.
With this switching rates, it is possible to detect theoccurrence of an electrical short between the bondwires in less than 2 min for a half ladder.
The pixel ladders, passing the WBC have been confirmed to be problem-free in a beta-ray irradiation
test conducted in a subsequent QA cycle. Our wirebonding electrical-short checker can check the qualityof wire bonding within a short time and help achieve a
steady production rate for a trouble-free pixel ladder.
References
1) Y. Akiba, et al.: RIKEN Accel. Prog. Rep. 43, 201(2010).
2) Y. Onuki, et al.: RIKEN Accel. Prog. Rep. 41, 165(2008).
3) K. Fujiwara, et al.: IEEE Trans. Nucl. Sci. 56, 250(2009).

- 207 -

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Quality assurance test of silicon pixel ladder for RHIC-PHENIX
M. Kurosawa, Y. Akiba, H. En’yo, K. Fujiwara,∗2 Y. Haki,∗3 K. Hashimoto,∗3 R. Ichimiya,∗1 J. Kanaya, M.
Kasai,∗3 K. Kurita,∗3 Y. Onuki,∗1 C. Pancake,∗4 R. Petra,∗5 M. Sekimoto,∗1 E. Shafto,∗4 B. Stephen, M.
Togawa,∗6 and A. Taketani
PHENIX is an experiment aimed at studying thespin structure of nucleons and studying hot and dense
matter at Relativistic Heavy Ion Collider (RHIC)
at Brookhaven National Laboratory (BNL). The
PHENIX detector will be upgraded with a silicon vertex tracker (VTX)1) in order to enhance its physics capabilities for spin and heavy ion program. The VTX
comprises a four-layer barrel detector built from two
inner silicon pixel detectors and two outer silicon strip
detectors. The main roles of the VTX are precision
measurement of decay position of heavy-flavor decays
and precision reconstruction of jet axis with its large
acceptance.
A silicon pixel ladder is the basic component of a silicon pixel detector. The two inner layers of the silicon
pixel detectors are made up of 30 silicon pixel ladders.
Mass production of silicon pixel ladders started by theend of 2009. In order to ensure correct operation before
the assembly of the silicon pixel detectors, quality assurance (QA) tests of the silicon pixel ladders need tobe performed. This report presents the recent resultsof the QA test for the fabricated silicon pixel ladders.
The structure of a silicon pixel ladder is shown in
Fig. 1. It consists of four silicon sensor modules, two

50 µm × 425 µm. Each pixel cell has an analog circuit
and a digital circuit as shown in Fig. 2. The analog

Fig. 2. An analog and digital circuit in a pixel cell.
.

circuit has a pre-amplifier followed by a shaper, a discriminator and a NAND gate to mask hot pixel. The
digital circuit consists of a synchroniser to the clock,two digital delay units to store a hit for the durationof the trigger latency, and a four-event FIFO that acts
as the multi-event buffer. The main test items are tocheck these components in order to ensure that theyfunction correctly after assembling. The items to beevaluated in the test are as flllows:(1) Current consumption.
• The current consumption of the analog andthe digital circuits of the readout chips aremeasured.
(2) JTAG functionality.
• It is confirmed whether the configuration settings in the chip can be read and written byusing the Joint Test Action Group (JTAG)
protocol.
(3) Mask functionality.
• The noisy pixels can be masked by a maskfunctionality.

Fig. 1. The structure of silicon pixel ladder.

(4) Minimum threshold and noise level.
• For all chips, the minimum threshold in all
pixel matrices are determined.

readout buses and a cooling support. Each component
is glued with Araldite 2011. The silicon sensor module is an assembly of a silicon pixel sensor and four
readout chips2) (ALICE1LHCb) bump-bonded to thesensor (bonded by VTTa) ) using bumps with diameters of 25 µm. The readout chip has 8192 pixel cells
arranged in 32 columns and 256 rows. The pixel size is
∗1
∗2
∗3
∗4
∗5
∗6
a)

KEK
Tokyo Metropolitan Industrial Technology Research InstituteDepartment of Physics, Rikkyo University
Department of Physics and Astronomy, Stony Brook University
CERN
Department of Physics, Osaka University
VTT Electronics, Tekniikatie 17, Epsoo, P.O. Box 1101,
FIN-02044 Epsoo, Finland(5) Mean threshold and mean noise for the complete
pixel matrix.
• The test pulse from the pulsar inside the chipis transmitted to each pixel cell and themean threshold and noise levels are determined.
(6) Performance of the pixel ladder with the βsource (90 Sr).
• Faulty bump bonds and the maximum efficiency are evaluated by β-source measurement.
The setup of the QA-test system is shown in Fig.
3. The assembled sensor modules (ladder) are con-

- 208 -

1.

Fig. 5. Response of pixel ladder to a β source. The horizontal and vertical axes represent pixel position
along the column and row directions, respectively. Low gray-levels represent low number of hits.

Fig. 3. Setup for QA test.

Fig. 4. Threshold distribution for a chip.

.

.

nected to Silicon PIxel Read-Out (SPIRO) modules.
The SPIRO modules provide all electricity, control thereadout chip of the sensor module and read out pixel
data. The front-end module (FEM) is an interface between the SPIRO modules and the data acquisition
system. The NOVEC HFE-7200 was used to the cool
readout chips. In the QA test, the DAC values on eachreadout chip were optimized. These DACs provide abias to the analog and digital circuits and are configured by using the JTAG interface. The minimum
threshold level for each chip was determined and hot
pixels were masked. In order to obtain a uniform pixel
matrix, the efficiency of each pixel was measured using
a test pulse by varying the amplitude of the pulse voltage. Then, the mean threshold level was determined.
Finally, the performance test of a pixel ladder with βsource was carried out.
So far, the QA tests of three pixel ladders have been
completed and the correct operation of the ladders has

been confirmed. The threshold distribution for a chipis shown in Fig. 4. The measured mean threshold of
3,700 electrons was considerably low comparing withto the 14,000 electrons of MIP. The typical response of
the pixel ladder with 16 readout chips to the β source isshown in Fig. 5. The inefficient area at the bottom ofcolumns 1, 9, 17, and 25 is attributed to the imperfectoptimization of DACs.
In summary, QA tests of three assembled pixel ladders were carried out. The reference voltage for DACs
were optimized, and the response of the pixel ladders
to the β source were measured. The results confirmedthat the three pixel ladders operate correctly.

2- 209 -

References
1) Y. Akiba et al.: RIKEN Accel. Prog. Rep. 43, 201(2010).
2) K. Fujiwara et al.: RIKEN Accel. Prog. Rep. 39, 207(2005).

RIKEN Accel. Prog. Rep. 43 (2010)

Use of time-domain reﬂectometry for impedance measurementof ﬁne-pitch and low-material-budget readout busof the PHENIX pixel detector
K. Fujiwara,∗1 A. Taketani, T. Kobayashi,∗1 T. Kondo,∗1 Y. Akiba, Y. Haki,∗2 S. Watanabe,∗3 M. Kasai,∗2
M. Kurosawa, H. En’yo, K. Kurita, M. Sekimoto, K. Hashimoto,∗2 J. Kanaya, Y. Onuki, M. Togawa,S. Baumgart, R. Ichimiya, and the PHENIX VTX group
The PHENIX detector system at the relativistic
heavy ion collider (RHIC) at the Brookhaven National
Laboratory will be upgraded by installing a four-layer
silicon vertex tracker (VTX) in 20101). The VTX consists of two inner silicon pixel detectors and two outersilicon strip detectors. It can enhance the capabilitiesof the PHENIX detector system, enabling the identiﬁcation of heavy quarks via the measurement of thedisplacement of vertices. This will facilitate investigations of new hot and dense nuclear matter producedin heavy-ion collisions and the spin structure of nucleons produced in polarized proton-proton collisions
at the RHIC1) . Our group is responsible for developing and fabricating the silicon pixel detectors. A newtransmission line was introduced in the silicon pixel detector for studying the above-mentioned topics. The
radiation length of the transmission line is 0.22%2,3).
The charged-particle-induced signals in silicon pixel
sensors are fed to dedicated bump-bonded readoutchips and converted to binary data. One readout chip
generates 32 × 256-bit data, where 256 represents thedepth of the data. The binary data are transferred
to a SPIRO board4) via ﬁne-pitch and low-materialbudget pixel buses. The signals on the SPIRO board
are converted to optical serial data and transmitted to
the PHENIX DAQ system. The pixel bus has alreadybeen produced.
This report describes the measurement of the characteristic impedance of the pixel bus by using timedomain reﬂectometry (TDR); the measurement was
performed at Tokyo Metropolitan Industrial Technology Research Institute (TIRI). A dedicated probe needle with a joystick was developed by NS Corporation.
The bus is fabricated using a ﬂexible printed circuit(FPC) board with copper and aluminum conductors
set on the polyimide insulators2,3). Figure 1 shows across section of the pixel bus.

∗1
∗2
∗3

Electronics Group, Tokyo Metropolitan Industrial Technology Research InstituteDepartment of Physics, Rikkyo University
Tokyo Metropolitan College of Industrial Technology

Through hall

120 µm40 µm

Plating
Cu Foil (Layer 1)
Polymide

7 µm
3 µm
25 µm

Bonding sheet
Cu Foil (Layer 2)
Polymide
Cu Foil (Layer 3)
Bonding sheet

35 µm
3 µm
25 µm
3 µm
35 µm

Cu Foil (Layer 4)
Bonding sheet

25 µm
3 µm
7 µm
35 µm

Al Foil (VDD)

50 µm

Plating

Bonding sheet
Al Foil (GND)
Bonding sheet

35 µm
50 µm
35 µm

Fig. 1. Cross section of a pixel bus.

The bus has two signal layers made of copper, twocopper layers for manufacturing purposes, and a power
layer and a ground layer that are both made of aluminum to minimize the material budget. The production process involves (1) pattern etching, (2) layer
stacking, (3) laser drilling, (4) through-hole plating,and (5) electrical continuity testing of each signal line.
The outline of bus is shared for ﬁnal shape. The bus
contains 128 data lines and 60 control and peripherallines in total. The area of the bus is 13.9 × 250 mm2 .
Hence, each signal and control line (copper line) is 30µm wide and 3 µm thick; the minimum spacing between two such lines is 30 µm2,3) .
The signal propagation behavior and impedancewere predicted by HSPICE simulation. In this report,
we compare the calculated impedance value with thevalue measured using the TDR system, Agilent 86100C
Digital Communication Analyzer with a 54754A TDR
module.
In general, the TDR system is used for the timedomain analysis of minute defects in coaxial cables or
microstrip lines5) . The TDR system consists of a highspeed pulser and an oscilloscope. A fast step-pulse isinjected into a signal line, and the reﬂected signal isthen observed on the scope. Changes in the characteristic impedance of the transmission line are explainedby the superposition of the injected pulse and reﬂected- 210 -

pulse in time domain.
Figure 2 shows a dedicated probe needle and a
joystick-type actuator developed by NS Corporation,
Musashino-shi, Tokyo. The needle has a tungsten contact for transmitting and receiving signals, a groundpad, and a semi rigid cable with an SMA female connector.

develop a new quality assurance procedure and to improve the yield rate of the plated-through hole making.
References

Fig. 2. Dedicated probe needle with a joystick-type actuator.

Figure 3 shows the changes in the characteristic
impedance of a transmission line of a pixel bus as measured in time domain. The rise time of the injection
pulse is 35 ps. The typical value of the impedanceof the transmission line is approximately 120 Ω. The
characteristic impedance calculated by HSPICE simulation is in the range 110−140 Ω2) . Thus, it is conﬁrmed that the calculated value agrees with the measured one.
160
140

Probe needle

120

Open end|Z| (Ω)

100

Transmission line

80
60
40

Bonding pads

2000Reference
0.5

1

1.5

2

2.5
ns

3

3.5

4

4.5

5

Fig. 3. Characteristic impedance measured by TDR.

We checked that the signals from the readout chips
are transfered correctly during both measurement andsimulation2) . Thus, we formulated a design procedureof FPC by using the HSPICE simulator and developed
an impedance evaluation method using TDR.
Using TDR measurements, defects in vias (platedthrough holes) can be detected after ﬁnal sharing. We
are continuing impedance measurement using TDR to- 211 -

1) Y. Akiba: RIKEN Accel. Prog. Rep. 43 (2010).
2) K. Fujiwara: Development of a silicon pixel tracker foran experiment of high energy heavy ion and polarized
proton collisions, Doctoral dissertation, Niigata University, 2007.
3) K. Fujiwara, et al.: IEEE Transactions on Nuclear Science 56, No.1 (2009).
4) R. Ichimiya: RIKEN Accel. Prog. Rep. 40 (2007).
5) J. R. Andrews: “TDR, Setp Response and “S” Parameter Measurements in the Time Domain,” Picosecond
Pulse Labs, Colorado, USA, Application Note AN-4,
May 1989.

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

GEM detectors for the experiment to measure the mass modiﬁcationof vector mesons in nuclei at J-PARC
S. Yokkaichi for the J-PARC E16 Collaboration
We proposed an experiment E161) to measure thevector meson decays in nuclei in order to investigate
the chiral symmetry restoration in dense matter. The
experiment is planned to be performed at the J-PARC
hadron experimental facility. The proposal of the experiment was granted scientiﬁc (“stage 1”) approvalby the PACa) in March 2007. For full approval, we are
required to show not only the experimental feasibility but also the prospects for acquiring suﬃcient funds
and even the prospects for beam line construction.
The aim of experiment is to perform the systematic
study of the mass modiﬁcation of vector mesons, especially φ meson, in nuclei. The mass modiﬁcationof vector mesons in hot and/or dense matter is predicted on the basis of the QCD; due to the restoration of chiral symmetry in such matter. On the other
hand, taking only hadronic many-body eﬀects into account, mass modiﬁcations in matter are also predicted.
Many experimental studies have been conducted, andthe mass modiﬁcations in hot/dense matter have been
observed, including in KEK-PS E3252) , of which theauthor were one of the collaborators. However, thecause of the modiﬁcation has not yet been conﬁrmed;
in other words, there is no consensus on the interpretations of the phenomena. To determine the cause,the systematic study of the modiﬁcation is requiredin order to accurately compare the data with various
theoretical predictions.
A goal of this experiment is to measure the φ meson
decays in the e+ e− channel with the statistics that are
two orders of magnitude larger than those of the preceding experiment E325; namely, there are 1 ×105 to 2
×105 events for each nuclear target, H, C, Cu, and Pb.
Thus, we can deduce the dependences of the modiﬁcation on the matter size and meson momentum, whichhave never been measured. At the same time, the e+ e−
decays of the ρ, ω, and J/ψ mesons can be measured.
For the experiment, we will use a 1010 -Hz, 30-GeV proton beam at the high-momentum beam line, which will
be constructed at J-PARC hadron experimental facility. To increase the statistics by a factor of 100, thebeam intensity is changed to achieve a factor of 10,
the acceptance of spectrometer is changed to achievea factor of 5, and the production cross section is increased by increasing beam energy to achieve a factorof 2. To cope with the interaction rate at the target
that has increased by a factor of 10, to 107 Hz, newspectrometer based on new technology should be built.
a)Program Advisory Committee for Nuclear and Particle
Physics Experiments at the J-PARC 50-GeV Proton Synchrotron

The development of detectors for the experiment has
been performed. There are two key detectors in the experiment, both use the GEM (Gas electron multiplier)technology. One is the Hadron blind detector (HBD),
which is to separate the electrons from the pions, andthe other is the GEM tracker, which is used to copewith the high rate that is expected to reach 5 kHz/mm2
at the most forward region of the proposed spectrometer. HBD is being developed at RIKEN and GEM
Tracker is being developed at University of Tokyo,
while a basic study on the GEM is being performed
at both. The status of development of the GEM and
GEM Tracker are reported in this article; the status ofdevelopment of HBD is reported elsewhere3) in this report. With lead-glass EM calorimeters, GEM Tracker
and HBD compose an electron-ID detector module asshown in Fig. 1.
Typically, a GEM is a thin kapton foil that has thincopper electrodes on both sides and many small holes(typically 70 µm in diameter, aligned in a triangularlattice with a 140-µm pitch). The typical thicknesses ofFig. 1. The schematic view of the electron-ID detector
module and drawings of GEM Tracker and HBD.

- 212 -

1

kapton and copper are 50 µm and 5 µm, respectively.
The typical sensitive area is 100 × 100 mm2 . Gas
ampliﬁcation occurs in the high electric ﬁeld in thesmall holes. Typical gas gain is 20 for a foil with anelectrode voltage of 340 V for such a typical 50-µmthick GEM in P10 b) gas; in order to obtain a suﬃcientgain, three or four foils are stacked.
The GEM was originally developed at CERN4) ,which was made using the chemical etching method.
In Japan, the plasma and laser etching methods wereadopted successfully to produce GEM at CNS, UTokyo and the RIKEN Cosmic radiation laboratory
5,6). Such domestic GEMs, especially 100 µm-thickliquid crystal polymer(LCP) foil, had greater stability
and higher gain than that of the typical CERN-madeGEM; however, the domestic GEMs were three times
as expensive as the CERN-made. It should be notedthat the cost of chemical etching in mass production is
expected to be decreased, but the cost associated withthe laser is proportional to the number of holes andnumber of GEMs; thus, the cost decrease due to themass production cannot be expected. In our experiment, the tracker and HBD should cover the largest
area among all existing GEM detectors in the world,
and thus, the size and cost are serious concerns.
The trial production of some types of GEMs for our
detectors was carried out by domestic companies. The
ﬁrst domestic production of a larger-size (200 × 200
mm2 and 300 × 300 mm2 ) 50 µm-thick kapton GEM
by chemical etching was carried out. The GEMs could
operate but their gain was lower than expected. The
control of the hole size in the etching process was notvery good, and the larger size than expectation might
have resulted in the lower gain.
Next, we successfully developed GEMs with a higher
gain by chemical etching of 50-µm-thick kapton withsmaller holes (diameters of holes are 45 ± 5 µm for
Kapton at the most narrow part, and 75 ± 5 µm for
Copper) and sizes of 100 × 100 mm2 and 200 × 200
mm2 . By the end of June 2010, sample with a sizeof 300 × 300 mm2 and with identical hole size will
be delivered and tested. When their successful operation is conﬁrmed, GEM Tracker will be economicallyconstructed.
The test indicated that the domestic 100 µm-thick
LCP GEM made by laser-etching is suitable for the
HBD. In CF4 gas, which is required for the HBD3) , a
higher voltage is required to achieve the same gain asthat achieved in P10 gas. Thus, the stability requirement for HBD is more strict than that for the tracker.
For reducing the cost and increasing the size, sometrials to produce a 100-µm-thick LCP GEM based ona diﬀerent technology are in progress. The chemical
etching of LCP was one of the tested technology, andﬁnally found to be unsuitable.
b)2

Ar 90% + CH4 10%- 213 -For the GEM Tracker, a thin read-out board with adouble-sided ﬁne-pitch strip was produced and tested
for comparison with the above GEMs using an electron beam of momentum 670 MeV/c and 2 GeV/c at
LNS-Tohoku and KEK, respectively. In electron measurement, reducing the amount of material is essential for reducing the radiative tail and the backgroundfrom the γ–conversion. Three GEM chambers using
the above GEMs and read-out boards, which consistof three tracking plane, will be placed in the tracking
region; the total radiation length of the three chambers
is less than 1.2%.
The read-out boards are made of 25-µm-thick kapton with 700- and 350-µm-pitch copper strip. We aim
to achieve a position resolution of 100 µm in order toachieve a mass resolution of 5 MeV/c2 for φ mesons.
The requirement is satisﬁed for the track injected thetracker vertically; using P10 gas and 700 µm-pitch
strip read-out board with charge information of signals. On the other hand, for a tilted track, e.g., a trackat 30◦ to the vertical, the resolution is deteriorated to150 µm or more. Further investigation is being carriedout by using timing information of signals, optimizing
the GEM HV conﬁguration and gas mixture, etc.
References
1) S. Yokkaichi; RIKEN Accel. Prog. Rep. 39, 219(2006), S. Yokkaichi et al.; J-PARC proposal No. 16(http://j-parc.jp/NuclPart/pac 0606/pdf/p16-Yokkaichi 2.pdf),

Lect. Notes Phys. 781 161 (2009).
2) M. Naruki et al.; Phys. Rev. Lett. 96, 092301 (2006),
R. Muto et al.; Phys. Rev. Lett. 98, 042501 (2007).
3) K. Aoki et al.; in this report.
4) F. Sauli, Nucl. Instrum. Meth. 386, 531 (1997).
5) M. Inuzuka et al. Nucl. Instrum. Meth. 525, 529(2004).
6) T. Tamagawa et al. Nucl. Instrum. Meth. 560, 418(2006).

RIKEN Accel. Prog. Rep. 43 (2010)

Development of a thick-GEM TPC for the J-PARC E15 experiment
F. Sakuma and M. Tokuda,∗1 members of the J-PARC E15 Collaboration[thick-GEM, TPC, J-PARC E15]
The J-PARC E15 experiment aims to determine thesimplest kaonic nuclear bound state K − pp by in-ﬂight
3
He(K − , n) reaction1) . The dedicated detector system consists of a beam-line spectrometer, a Cylindrical
Detector System (CDS), and a neutron TOF counter.
The key point of such measurement is to accurately
identify Λ and Σ decays in the CDS using their secondary vertex reconstruction because the expected decay modes of K − pp are pΛ/pΣ0 and pπΣ. In order toperform these measurements, we have been developinga Thick Gas Electron Multiplier (TGEM) Time Projection Chamber (TPC) as an inner tracker for the E15
upgrade. For the TPC, the spatial resolution in the Z
direction should be less than 1 mm, and the material
budget for detector acceptance should be minimized asmuch as possible.
The TPC is cylindrical in shape with an inner diameter of 170 mm and an outer diameter of 280 mm and isﬁlled with P-10 gas at atmospheric pressure. The drift
length is 30 cm with ﬁeld cages of a double-sided Flexible Printed Circuits (FPC) having staggered strip electrodes. A photograph of the TPC is shown in Fig. 1.
We use a double-TGEM structure for ampliﬁcation,and signals are read out with 4-mm-long and 20-mmwide pads on a standard PCB. The TGEM is economically constructed from double-clad 400-μm-thick FR4plate using standard PCB techniques. It has mechanically drilled holes with diameters of 0.3 mm and chemically etched rims typically at 0.03 mm around each hole
to prevent electrical discharges. The TPC with TGEM
are advantageous because TGEM do not require support frames, which are essential when standard GEM
foils having thickness of 50 μm are used2) .

vider with a resistive chain, and the read-out pad witha charge sensitive preampliﬁer. The required eﬀective
gain is about 104 , and the stability of the gain andenergy resolution should be about 20% and 10%, respectively. Figure 2 shows the eﬀective gain of the
double TGEM measured with 55 Fe having four typesof rim conﬁgurations, and Fig. 3 shows the stabilityof the gain and the energy the resolution for the same
conﬁgurations. All types of TGEM achieve an optimal eﬀective gain of over 104 , but TGEMs with larger
rims require a higher voltage. Moreover, TGEMs without any rims and those with small rims (30 μm) work
rather stably; however, TGEMs with large rims (100and 50 μm) are unstable. This instability of the largerims TGEM is possibly caused by the charging up of
the insulator that was not metalized, but this behavior
is not yet understood well. Further studies of the basic TGEM behavior and performance are in currently
progress.

Fig. 2. The eﬀective gain of the double TGEM.

Fig. 1. A photograph of the TPC.

In order to study the performance of the TGEM,
we used a prototype TGEM with an active area of
10 × 10 cm2 produced by REPIC Corp., Japan. Measurements were carried out with double-TGEM conﬁguration using a test bench consisting of a gas chamber, the TGEMs operating in cascade, a voltage di∗1

Department of Physics, Tokyo Institute of Technology

Fig. 3. The stability of the gain the and energy resolutionof the double TGEM.

References
1) E15 proposal, http://j-parc.jp/NuclPart/pac 0606/pdf/p15Iwasaki.pdf2) F. Sauli, Nucl. Instrum. Meth. A 386, 531 (1997).

- 214 -

RIKEN Accel. Prog. Rep. 43 (2010)

Development of Cylindrical Detector System (CDS) for J-PARC E15
Experiment†
K. Tsukada for J-PARC E15 collaboration[ Nuclear physics, strangeness ]Recently, significant progress has been made to
study on deeply bound kaonic nuclei. Although there
are several experimental reports on the search fordeeply bound kaonic nuclear states1–6) , results are still
controversial because there is no conclusive evidence
for the observation of such bound states. As has beenfound in experimental and theoretical studies the binding energy and decay width of the K − pp state varyfrom a few 10 MeV to around 100 MeV.
To address this issue, the J-PARC E15 experiment
was proposed. The aim of this experiment was tosearch for the simplest kaonic nuclear bound state,
namely K − pp, via the in-flight 3 He(K − , n) reaction
using a 1.0 GeV/c K − beam7) . This experiment isadvantageous because it allows for the simultaneous
measurement of the missing-mass spectra of the primary neutrons and the invariant-mass spectra of the
expected decay particles, K − pp → Λp → pπ − p.
The E15 spectrometer has four components: a beamline spectrometer, a cylindrical detector system (CDS)
with a liquid 3 He target, a beam sweeping magnet, anda neutron time-of-flight (TOF) wall. The decay particles from the expected decay K − pp → Λp → pπ − p aredetected by the CDS, forward neutrons whose flight
length is approximately 15 m are detected by the TOF
wall. Incident kaons that pass through the target are
deflected by the beam sweeping magnet placed immediately after the CDS. By the assumption of the K − ppbinding energy to be 100 MeV/c2 , the expected spectrometer performance for the K − pp measurement is
9.2 MeV/c2 (σ) for the missing-mass resolution and 16
MeV/c2 for the invariant-mass resolution. The CDS
preparation status is described below.
In the CDS, all the detectors are configured cylindrically. The trajectory of the particles is reconstructedwith the Cylindrical Drift Chamber (CDC) on a cylindrical drift chamber (CDC), which operates in a magnetic field of 0.5 T generated by a solenoid magnet. A
cylindrical detector hodoscope (CDH) surrounds CDC
and is used for the trigger counter and the particle
identification hodoscope.. The solid angle of the CDS
at the center is approximately 7.4 sr.
The CDC consists of two 200 mm thick aluminum
end-plates, a carbon fiber reinforced plastics (CFRP)
tube with a thickness of 1 mm as the inner wall, and six
aluminum blocks placed outside the tracking region.
The CDC uses gold-plated tungsten with a diameter of
30 µmφ as sense wires and gold-plated aluminum witha diameter of 100 µmφ as field and guard wires. The

total length along the beam axis of tracking volume
is approximately 840 mm. A 50:50 mixture of Ar andethane (1 atm) is used. The CDC has 15 layers ofhexagonal cells with a typical drift length of 9 mm; thecells are grouped into 7 super layers (A1, U1, V1, A2,
U2, V2, A3). Information of a longitudinal position
along the beam axis is obtained by 8 stereo layers witha typical tilt angle of 3.5◦ . The number of readout
channels is 1816, and the total number of wires in the
CDC is 8064. Commissioning of the CDC is currently
underway, and a typical spacial resolution of 200 µm is
achieved by measuring trajectories of the cosmic raysin the absence of a magnetic field. The CDH consistsof 36 segments, each of which is individually mounted
on the inner wall of the solenoid magnet. Hamamatsutype R7761 fine-mesh photomultipliers (PMTs) with adiameter of 1.5 inch are selected. The time resolutionof the CDH measured using cosmic rays is typically71 ps, which indicates that the design goal has beenachieved. The CDC and CDH have been successfully
installed in the solenoid magnet, as shown in Fig. 1.
Excitation of the solenoid and evaluation of the CDC
and CDH performance in the magnetic field will be
carried out in the near future.

Fig. 1. Photograph of the CDS. The CDC and CDH are
installed in the solenoid magnet.

References
1) M. Sato et al.: Phys. Lett. B 659, 107 (2008).
2) T. Suzuki et al.: Mod. Phys. Lett. A 24, 442-445 (2009).
3) T. Kishimoto et al.: Prog. Theor. Phys. 118, 181(2007).
4) M. Agnello et al.: Phys. Rev. Lett. 94, 212303 (2005).
5) G. Bendiscioli et al.: Nucl. Phys.A 789, 222 (2007).
6) T. Yamazaki et al.: arXiv:0810.5182 [nucl-ex].
7) M. Iwasaki et al.: Proposal of J-PARC 50-GeV PS “Asearch for deeply-bound kaonic nuclear states by inflight 3 He(K− ,n) reaction” (2006).

- 215 -

RIKEN Accel. Prog. Rep. 43 (2010)

Development of a Cylindrical Drift Chambber for an experimental
search for K − pp bound states at J-PARC
T. Hiraiwa,∗1 Y. Fujiwara,∗2 M. Iio,∗3 K. Itahashi,∗3 M. Iwasaki,∗3,∗4 H. Kou,∗4 H. Ohnishi,∗3 H. Outa,∗3 F.
Sakuma,∗3 M. Tokuda,∗4 D. Tomono,∗3 K. Tsukada,∗3 T. Yamazaki,∗2,∗3 and the J-PARC E15 Collaboration
1

Introduction

The J-PARC E15 experiment aims to search forK − pp bound states using in-flight (K − , n) reaction
on 3 He1) . In this experiment, we measure the missing
mass in the in-flight (K − , n) reactions and the invariant mass of the decay such as K − pp → Λp → π − pπ −, simultaneously. We newly developed a Cylindrical
Detector System (CDS) for the invariant mass study,
which mainly consists of a large solenoid magnet, a
Cylindrical Drift Chamber and hodoscope counters(See Fig. 1).
In this report, the design and current status of Cylindrical Drift Chamber are presented.

at ground potential. The read-out electronics consistof a amplifier-shaper-discriminator (ASD), LVDS-ECL
converter and a time-to-digital converter (TDC ).

Fig. 2. A schematic view of the Cylindrical Drift Chamber(CDC). A left pannel shows a frame structure of the
CDC, and a right pannel shows a cell configuration of
the CDC.

3

Fig. 1. A schematic view of Cylindrical Detector System(CDS).

2

Design for Cylindrical Drift Chamber

As shown in Fig. 2, a Cylindrical Drift Chamber(CDC) has an inner diameter of 150 mm and an outer
diameter of 530 mm and the total length is 950 mm.
CDC consists of two aluminum end-plates of 20 mm
thichness, a 1 mm thick CFRP cylinder as an innerwall, and six aluminum posts which are placed outside a tracking volume. Gold-plated tungsten wires
with 30 µm φ are used for sence wires and gold-plated
aluminum wires with 100 µm φ for guard and field
wires. All wires are supported by feedthroughs witha bushing inserted at the end. A tracking volume of
CDC is filled with argon(50%)-ethan(50%) mixed gas
at 1 atm. CDC has total 15 layers of hexagonal cellswith typical drift length of 9mm, which corresponds
to 7 super layers (A1 U1 V1 A2 U2 V2 A3 ). The
number of the readout channels is 1816 and the total
number of wires is 8064. A high voltage is applied to
the field and guard wires and the sense wires are kept
∗1

∗2
∗3
∗4

Department of Physics, Kyoto University, Japan
Department of Physics, The University of Tokyo, JapanRIKEN Nishina Center, RIKEN, Japan
Department of Physics, Tokyo Institute of Technology,
Japan

Performance test of CDC

The development of the CDC, including read-out
electronics, have been completed in mid-2009, and thecommissioning of the CDC started at the J-PARC
K1.8BR experimental area. Fig 3 shows a result of thecosmic ray test, together with results of sumulations,assuming the intrinsic resolution of 150, 200 and 250µm. By comparing with the results of simulations, theintrinsic resolution of 200 µm was achieved for straight
tracks.
In March 2010, the excitation test of the solenoid
magnet will be done, and the performance test of CDC
in the magnetic field will start.

Fig. 3. Layer dependence of the CDC resolution. The blackline shows a measured resolution from cosic ray test.
The red, green and blue lines corresponds to results ofsimulations, assuming intrinsic resolution of 150, 200
and 250 µm, respectively.

----References
1) M. Iwasaki et al., Proposal to the J-PARC 50 GeV Proton Synchrotron.

- 216 -

RIKEN Accel. Prog. Rep. 43 (2010)

Development of a Hadron Blind Detector for the J-PARC E16
Experiment
K. Aoki, for the J-PARC E16 Collaboration[HBD, GEM, Cherenkov detector, chiral symmetry, mass modiﬁcation, vector meson]
Introduction

light baffle

The J-PARC E16 experiment
was proposed to investigate the origin of hadron mass through the mass
modiﬁcation of vector mesons in nuclei. The vector
mesons (ρ, ω, and φ) are produced in p+A reactions
and the mass is reconstructed by using the e+ e− decay. A Cherenkov detector with a large acceptanceand ﬁne segmentation is required for electron identiﬁcation. The Hadron Blind Detector (HBD)3) , which
is a mirrorless and windowless Cherenkov detector, isideal for the purpose. It was originally developed for
the PHENIX experiment.
The HBD is a box containing pure CF4 , and theinner bottom surface is covered with photocathodes
sensitive to Cherenkov light. A photocathode consists of a stack of Gas Electron Multipliers (GEMs) on
top of which CsI is evaporated. CF4 functions as anampliﬁcation gas and a Cherenkov radiator. The water and oxygen contamination levels should be kept at∼ 10 ppm since they absorb vacuum ultraviolet light,
which is of interest. CsI is a deliquescent material.
radiator length= 50 cm
60 cm

beam

10 cm

photocathode(inside the HBD vessel)

Fig. 1. Photograph of the HBD prototype for J-PARC E16.

2

HBD prototype for J-PARC E16

We have developed a prototype of the HBD for the
J-PARC E16 experiment. Figure 1 shows a photograph of the prototype. The vessel has approximately
the same size as a module of the planned detector,
which consists of 26 modules. The length of the radiator is 50 cm. Figure 2 displays the photocathode thatpartially covers the inner bottom surface of the vessel. a) It is constructed with two layers of LCP-GEMs
with a thickness of 100 µm with CsI on top of the layers. The Cherenkov photons are converted into photoelectrons by CsI. The photoelectrons are ampliﬁeda)

In Fig. 1, the beam direction is left to right, while in Fig. 2,
the direction is from top to bottom.

Chph erenoto kon v

1,2)

4 mm photo-

electron

1.5 mm2 mm

incidelect ent
ron

1

mesh
n
atio
CsI

iz
ion

GEM
GEM

readout pad
Fig. 2. Photocathode of the HBD prototype.

by the two layers of GEMs, and the ampliﬁed signal isthen read out using the pads. A mesh is placed over
the top GEM to manipulate the electric ﬁeld above
the top GEM. When a reverse bias ﬁeld is applied
between the mesh and the top GEM, electrons fromenergy loss (dE/dx) are mostly swept out while photoelectrons are not. Therefore, the HBD is sensitive
to photoelectrons. The pad is hexagonally shaped andthe radius of the circle circumscribing it is 16.9 mm,
which is roughly equal to the size of a Cherenkov blob.
The use of a thicker GEM leads to a larger gain (∼ 500with 400 V/50 µm) in the ﬁrst stage and larger tolerance to sparks, unlike the regular 50 µm kapton-GEMs(∼ 10 with 500 V/50 µm) used for the PHENIX experiment. A large gain in the ﬁrst stage is important toobtain a suﬃciently larger signal from Cherenkov photons than that from energy loss between the ﬁrst andsecond GEMs.
A light baﬄe (an aluminum plate) was prepared tocover the photocathode to shield the Cherenkov photons. Therefore, the diﬀerence in the results obtainedwith and without the baﬄe would provide direct evidence of Cherenkov radiation.
The number of photoelectrons measured with the
PHENIX HBD is ∼ 22. Although there are diﬀerences
between the prototype and the PHENIX HBD, e.g., in
the thickness of the GEM and the spacing between the
GEMs, the diﬀerences are expected to be insensitive
to the number of photoelectrons. A rejection factor of
100 can be achieved with a threshold at ∼ 16 electrons.

- 217 -

a.u.

0.1

SS

with baffle(dE/dx only)

0.08

O

K

0.06

0.02

IN

PR

OR

W

without Baffle(dE/dx +Cherenkov radiation)

0.04

E
GR

0

-5

0

5

10

15

20

photo-electronsFig. 3. Observed charge distribution with the baﬄe(dashed line) and without the baﬄe (solid line). The
diﬀerence between these two distributions provides direct evidence of Cherenkov radiation.

3

Beam test

A beam test was performed using a positron beamwith a momentum of 670 MeV/c at the Research Center for Electron Photon Science, at Tohoku University, in December 2009. The HBD was sandwiched
between scintillators to conﬁne the triggered incident
electrons to an area of 1 cm × 1 cm, which was smallenough for the incident positron to hit a particularpad. Therefore, the target pad and six neighboring
pads were read out and the values were summed toobtain the Cherenkov signal. The water contamination level was ∼ 60 ppm and the oxygen contaminationlevel was ∼ 30 ppm. The contaminants were expected
to absorb ∼ 30 % of the Cherenkov photons.
Figure 3 shows the distribution of charge summed
over seven pads, which were expected to be larger thanthe Cherenkov blob from triggered positrons. A reverse bias of 20 V/4 mm was applied. It is evident thatthe prototype successfully detect Cherenkov radiationfrom the positron beam. The number of photoelectrons was ﬁve or six. The prototype is the ﬁrst to bemade in Japan and can clearly detect Cherenkov radiation. However, it is not enough to achieve a rejection
factor of 100 while keeping reasonable eﬃciency.
4

Discussions on improvement

The loss of 30% of Cherenkov photons is due to absorption by residual water vapor and oxygen. Therefore, in principle, the loss can be reduced by eliminating the contamination, and such an improvement ispractically possible. However, it is diﬃcult to achievea contamination level of 10 ppm level for water in ashort test experiment since materials absorb water vapor and hold it for a long time. It takes more than amonth to achieve a level of ∼ 10 ppm with dry gas ﬂow

Fig. 4. Quantum eﬃciency vs photon energy for the prototype (circle) and the PHENIX HBD4) (box)and this is not possible in a short test experiment. In
addition, a large amount of gas is needed. Therefore,a gas circulation system are required. Such a system
is being developed for the E16 experiment.
To qualitatively understand the number of photoelectrons, the quantum eﬃciency (QE) of the photocathode is determined. The results are displayed inFig. 4. Although CF4 is transparent to photons up
to 11.5 eV, it is diﬃcult to measure the QE above anenergy of 10 eV (120 nm). Therefore, extrapolation isneeded to calculate the number of expected photoelectrons, which leads to a large systematic uncertainty.
As far as the measured energy range is concerned, adiﬀerence in energy dependence is seen above 9 eV.
This indicates that there is room for improving the
QE of the prototype. A study is currently underway
to determine the reason for the diﬀerence.
5

Summary

We have built a prototype of the HBD for the JPARC E16 experiment. The prototype successfully
detected Cherenkov radiation, and the number of photoelectrons was ﬁve or six. The QE of the photocathode was also measured and compared with that of the
PHENIX HBD photocathode. A diﬀerence was seenin the energy dependence of the QE above 9 eV, andis the reason for this diﬀerence is currently being investigated. Improvement from QE and gas purity is
expected.
References
1) S. Yokkaichi et al.: RIKEN Accel. Prog. Rep., this volume.
2) http://rarfaxp.riken.go.jp/~yokkaich/paper/
jparc-proposal-0604.pdf
3) A. Kozlov et al.: Nucl. Instrum. Meth. A 523, 345(2004).
4) B. Azmoun et al.: IEEE Trans. Nucl. Sci. 56, 1544
(2009).

- 218 -

RIKEN Accel. Prog. Rep. 43 (2010)

Design and Construction of Station-3 Drift Chamber for
FNAL-E906 Experiment †K. Nakano, Y. Goto, Y. Miyachi,∗1 , S. Miyasaka∗2 ,S. Mizugashira∗2 , S. Sawada∗3 , T.-A. Shibata∗2 , and A. Taketani
12Introduction

E906/SeaQuest is a ﬁxed-target experiment for
which preparations are being made at Fermilab, USA.
In this experiment, a 120-GeV proton beam extracted
from the Fermilab Main Injector is used to measure
the cross section of the Drell-Yan process, q q̄ → γ ∗ →µ+ µ− , in proton-nucleon reactions by detecting theﬁnal-state muon pair. The main goal of this experiment is to investigate the ﬂavor asymmetry of the sea¯ in protons1) . In particular, we foquarks (ū and d)cus on the asymmetry of sea quarks at a large xBj(� 0.25), where xBj is the fraction of the momentum
carried by the scattered quarks.
The E906 detector should be capable of not only
detecting the muon pairs produced in the Drell-Yan
process but also eliminating the huge number of lowmomentum charged particles, particularly the muons
formed in the reaction p + N → π ± + X → µ± + X � .
Figure 1 shows the E906 detector setup, where the proton beam comes from the left-hand side. The target
used is liquid hydrogen or liquid deuterium stored in acryogenic target cell. A focusing magnet labeled as “FMag” in Fig. 1 condenses signal muons into the detector acceptance cone and sweeps out low-momentum
background muons. A large iron block placed inside
the focusing magnet acts as a hadron absorber and abeam dump. Stations 1, 2 and 3 are multi layer drift
chambers (DCs). At these stations, the positions of
the passing muons are detected, and the tracks andmomenta of the muons are reconstructed with an analyzing magnet labeled as “K Mag” in Fig. 1; this magnet deﬂects the muons in the horizontal direction. Station 4 comprises alternate layers of drift tubes and ironabsorbers. It identiﬁes high-momentum muons by selecting the particles that penetrate the absorbers toa suﬃcient depth. Each station has one or two hodoscopes for triggering muon-pair events.
The proton beam becomes available in October2010. Data will be recorded intermittently over a period of three years. We, the E906 Japanese group, takecharge of the construction and operation of Station 3.
This article reports the design and construction of a
new drift chamber for Station 3.

∗1
∗2
∗3

Performance Requirements

To optimize the position and size of all the detectors, the expected signal statistics for various detector
settings have been evaluated using a Monte Carlo program. The optimal conditions are as follows. Station
3 positioned 19 m away from the target, and the sizeof the acceptance of Station 3 is 3.2 m in the verticaldirection and 2.2 m in the horizontal direction. The
position resolution required at Station 3 is less than
400 µm. The expected background rate has been evaluated using the GEANT detector simulator2) . It is at
maximum 5 kHz/cm2 at Station 3; hence, at this station, the DC is required to detect muons up to thisrate without loss of detection eﬃciency and gas ampliﬁcation gain.
The DC at Station 3 consists of six layers called U,
U’, X, X’, V and V’. For precise measurement of themuon track position in the bending (horizontal) direc�
tion, all the wires are aligned vertically, while U( ) and(� )◦V are tilted by 14 . A mixture of argon and ethane(50:50) is used because it is a standard gas mixture
commonly used for other drift chambers.
3

DesignFirst, the entire structure of Station 3 is examined.
Because the size of the Station 3 acceptance cone (3.2m × 2.2 m) is large, we decided to divide this station into two parts so that the design and construction
could be completed within a given period (1.5 years).

Yamagata University
Tokyo Institute of Technology
KEK

Fig. 1. Schematic of detector setup (top view).

- 219 -

eﬀect of electron diﬀusion, which is well below the required overall position resolution of 400 µm.
4Construction

The drift chamber design was ﬁnalized in July 2009.
Immediately after, construction work was commenced
in Japan. The frame was completed by the end of
September. All the wires were placed in late November, and the Mylar windows were closed. Figure 4
shows an image of the Station 3 DC recorded in January 2010. The argon-ethane mixture is ﬂowed in orderto perform various basic tests before the DC is transported to Fermilab. The DC will be installed in theexperimental hall in July 2010, and tested with theﬁrst proton beam in October.
References
1) J. Arrington et al., Proposal of E906 Experiment,
http://www.phy.anl.gov/mep/drell-yan/proposals/.
2) CERNLIB Webpage, http://cernlib.web.cern.ch/cernlib/
3) CERNLIB Webpage, http://garﬁeld.web.cern.ch/garﬁeld/

Positron drift lines from a wire
y-Axis [cm]The top half is covered by the new DC that we constructed, and the bottom half is covered by the existing DC at Fermilab. In this conﬁguration, the frameof the two chambers occupy a part of the Station 3 acceptance. We have conﬁrmed that multiple scatteringsof muons in the frame material are suﬃciently small tosatisfy the required momentum resolution.
On the basis of studies that will be described later,
we adopted the cell structure shown in Fig. 2. The supposed HV values are −2.8 kV for the ﬁeld and cathodewires and −1.4 kV for the guard wires. The gas ampliﬁcation gain is expected to be O(105 ), as decided bystudies performed using the Garﬁeld gas-detector simulator3) . Two layers such as X and X’ are staggered to
one-half of their cell width so that the left-right ambiguity in the drift direction is eliminated. Since theHV values are common to all cathode wires, the twolayers can share a cathode-wire plane so that the total number of wires and the amount of frame material
used are reduced. The number of sense wires, and thus
readout channels, is 768, and the number of ﬁeld andguard wires is 4368.
Figure 3 shows the paths and contour lines of electron drift in one cell. Because the E-ﬁeld strength isso adjusted that the electron drift velocity is almost
constant (saturated), the drift length becomes proportional to the drift time. The drift-time deviation has
also been evaluated using Garﬁeld; it is ∼2 ns or 100µm (for a drift velocity of 50 µm/ns), including the

Cell: FNAL E906 St.3 DC
Gas: C2H6 50%, Ar 50%, T=300 K, p=1 atm

Isochrone interval: 0.02 [µsec]

1
0.8
0.6
0.4
0.2
0

guard wire (φ 80 µm)-0.2

cathode wire (φ 80 µm)

Usense wire (φ 30 µm)

U’

field wire (φ 80 µm)

-0.4
-0.6
-0.8
-1
5

4.8

4.6

4.4

4.2

4

3.8

3.6

3.4

3.2

3

cathode-wire space (10 mm)

x-Axis [cm]cathode-to-guard gap (10 mm)

Fig. 3. Paths and contour lines of electron drift simulatedwith Garﬁeld for X cell. This ﬁgure shows the unit cellfor X, i.e., a sense wire is at the center and is surroundedby eight ﬁeld/cathode wires.

Xcell height (20 mm)

X’cell width (20 mm)
guard-wire space (10 mm)

V

V’

Fig. 2. Cell structure of new drift chamber for Station
3. X and X’ wires run perpendicular to the plane ofthis paper, and U, U’, V and V’ wires are tilted by
14◦ . The distance between neighboring tilted wires is
10 cos(14◦ ) = 9.7 mm. Blue boxes represent unit drift
cells.

- 220 -

Fig. 4. Photograph of new drift chamber for Station 3.

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Computing and Network Environment at RIKEN Nishina Center
T. Ichihara, Y. Watanabe, and H. Baba
We have been operating Linux/Unix NIS/NFS cluster systems1,2) at the RIKEN Nishina Center. The
major part of the systems is installed in the 1F serverroom of the RIBF building that is equipped with emergency power supply and UPS systems, which ensure
the non-stop operation of the computing system, evenduring power outages.
Figure 1 shows the current configuration of theLinux/Unix servers at the Nishina Center. We are
adopting Scientific Linux3) as the primary operating
system; this operating system has been developed at
the Fermi National Laboratory and is widely used ataccelerator research facilities worldwide and by the nuclear physics and high-energy physics communities.
The host RIBF is used as the mail server, NFS serverof the user home directory /rarf/u/, and NIS masterserver. Approximately 500 user accounts are registeredon this server. fibre channel RAIDs with capacities of
10 TB and 5.6 TB with fibre channel hard disk drives/rarf/w/ and /rarf/d/ are connected to the RIBFDATA01 server for data analysis and raw data storage
for the RIBF experiment. The host RIBF00 is used as
an ssh login server to provide access to users from theoutside the Nishina Center; it is also used as a generalpurpose computational server, printer server, and a
gateway to the RIBF intranet. Public-key authentication is used for ssh login to improve security. New
SSL server certificates have been installed in RIBF and
RIBFUSER for secure encrypted communication.
Postfix is used as the mail transport software andDovecot is used for IMAP and POP services. Thesesoftware packages enable secure and reliable mail delivery. The hosts RIBFSMTP1/2 are mail front-end
servers, and they are used for tagging spam mails andisolating virus-infected mails. Sophos Email Security
and Control (PMX) was installed on these servers in
March 2008 and it has been working well and serving the intended purposes. The probability of being
identified spam by PMX is approximately 99%.
An anonymous ftp server, FTP.RIKEN.JP, is managed and operated at the RIKEN Nishina Center. We
have changed the hardware of the server from Sun Fire
V40z to HP ProLiant DL380G6 to improve the IO performance. This server is has a speed of 10 Gbps andconnected to the Local Area Network (LAN) using thedual-port 10GbE NIC with a PCI express interface.
The average network transfer rate of this server is approximately 50 MBps, and it is one of the most heavily
loaded server in RIKEN. A 26 TB SATA RAID systemwith quad-port 8 Gbps Fibre Channel interface has
been added to this server. Major Linux distributions,which include Scientific Linux, CentOS, Ubuntu, Fe-���������������
��������������

�����������������
��������
��������������

���������������������
����������������������� �����������������������

�������������
������� ������������ ���������������� ������������������������������
����������������������
����������������������
��������������������
����������������������

��������
����������

����������

����������������
����������������������
��������� �����������

�������������

�����������������
�����������������������

�������������
���������������

���������
�������������������
�������
�������
�������� �����������

��������
����������

�������������������������

����������������������
�������� ���������
��������

��������

�������

��������

������������ �������������

������

��������

��������� �������������
������������

�������� �������

������������

��������� ���������
���������

��������

�����������������

���������� �����������

�������

�����������
���������������������
����������������

Fig. 1. Configuration of RIBF Linux cluster.

dora, Debian, OpenSUSE, Mandrake, Slackware, andVine are mirrored daily at the ftp server for the convenience of the facilitating high-speed access to theirusers. Archives on the server are available via anonymous ftp, http, and rsync protocols.
The development of the RIBF Data Acquisition system (DAQ) is described elsewhere.4)
Most of the users of the Nishina Center have e-mailaddresses of one of the following forms:
username@ribf.riken.jp and username@riken.jp.
The former represents an e-mail address of the mailserver (RIBF) of the RIKEN Nishina Center, while
the latter represents an e-mail address of the mailserver (POSTMAN) of the RIKEN Advanced Centerfor Computing and Communication.
References
1) http://ribf.riken.jp/
2) T. Ichihara et al.: RIKEN Accel. Prog. Rep. 42, 198(2009).
3) https://www.scientificlinux.org/
4) H. Baba et al.: In this report.

- 221 -

1

RIKEN Accel. Prog. Rep. 43 (2010)

Time-Stamping System for RIBF experiments
H. Baba, T. Ichihara, T. Ohnishi, S. Takeuchi, K. Yoshida, Y. Watanabe, S. Ota,∗1 and S. Shimoura∗1
The development of time-stamp-based data acquisition (DAQ) systems is currently in progress at several
accelerator facilities1,2) . Today, time-stamping systems become one of the basic requirements in nuclearphysics experiments. They are required for complex
triggering measurement and they facilitate the interconnection between diﬀerent DAQ systems. Here, wereport the newly developed time-stamping system for
RIBF experiments.
In this system, 48-bits-deep time stamps with a precision of 10 ns (100 MHz) are used. This time speciﬁcation corresponds to a period of one month, which is
suﬃcient to perform a series of experiments. The timestamping system is installed in each sub-DAQ system,
and all data are stored together with the time-stamp
information. Once the data is stored, the data of therequired events can be extracted in accordance withthe coincidence condition. This facilitates the coincident measurement with individual triggers using several DAQ systems.
The conﬁguration of the time-stamping DAQ system is shown in Fig. 1. The clock signal is transmitted to each sub-DAQ system. According to its
trigger, each sub-DAQ accumulates data. The timestamp-based event builder, which is newly developed,
constructs complete event by using separately stored
data obtained from each sub-DAQ system. Its coincidence condition is programmable. This time-stamping
system is constructed by modifying the existing RIBF
DAQ3) system so that includes time-stamp information. The seamless integration of the individual trigger
system and the common trigger system is achieved.
In order to manage the time-tamp information,
Logic Unit for Programmable Operation (LUPO) modules are developed one with CAMAC and another with
VME form. A LUPO module is a simple logic module
based on Field Programmable Gate Array (FPGA) for
general purposes. A user can implement customized
circuits on the FPGA for functions other than the timestamping function, for example, for the input register,
output register, interrupt register, coincidence register, scaler, rate divider, and gate and delay generator.
Figures 2 and 3 show photographs of CAMAC LUPO
and VME LUPO, respectively. The main components
and speciﬁcations are listed below.
• Components– User FPGA
– CAMAC/VME interface CPLD
– 50-MHz crystal oscillator– 8 LED∗1

Center for Nuclear Study, University of Tokyo

DAQ A

FEC

DAQ B

FEC

FEC
FEC

CCEB

CCEB
Trigger B

Trigger A

Raw
Raw
Data
Data

TSEB
Data

Data
Storage

Clock
Analyzer
TSEB

Fig. 1. The configuration of the time-stamp-based DAQ
system. CCEB is the common trigger + common deadtime-based event builder. FEC is the front-end computer for CAMAC/VME. Details on CCEB and FEC
are given in Ref 1. TSEB is the time-stamp-based event
builder.

– 4 NIM inputs– 4 NIM outputs– 34-pin MIL connector for LVDS I/O and
LVTTL I/O
• FPGA Speciﬁcation– Xilinx Spartan 3E (XC3S500E)– 500-K system gate
– 73-Kbits distribute-RAM– 350-Kbits block-RAM– 4 digital clock managers (including DLL)CPLD is installed as a interface for the CAMAC andVME buses to simplify the communication protocols.
Because of this interface, the FPGA circuit can beconstructed without taking into consideration the differences between CAMAC and VME. A 34-pin MIL
connector is used for 16 LVDS I/O and 32 LVTTL
I/O. The LVDS and LVTTL are selected on the basis of FPGA constraints. The FPGA has 4 digitalclock managers including a delay-lock-loop (DLL) circuit. The DLL provides the functions of the clock-skew
elimination and the frequency synthesis.
The time-stamping function is implemented on
LUPO. The block diagram of the time-stamping circuit is shown in Fig. 4. The DLL circuit generates a
100-MHz clock signal from a 25-MHz external clock
or a 50-MHz internal oscillator. Even if the internal- 222 -

㪝㪧㪞㪘
25 MHzExternal clock
DLL
External

8 LEDs100 MHz clock
Clear

4 NIM Inputs

Interface
CPLD
User
FPGA

16 LVDS I/O
32 LVTTL I/O
Programmable

48 bitCounter

Trigger

SwitchLatch

4 NIM Outputs

Latch

FIFO Memory
48 bitx1024 cell

48 bitCounterFig. 2. CAMAC version of LUPO.

100 MHz clock
50 MHzOscillator

DLL
Internal

Fig. 4. The block diagram of the time-stamping circuit
which is implemented in FPGA.

8 LEDsInterfaceCPLD

4 NIM Inputs
16 LVDS I/O
32 LVTTL I/O
Programmable

CAMAC / VME
Interface

The developed time-stamping system was used in experiments held in November and December 2009. Oneof the experiments was for the measurement of the(t,3 He) transfer reaction4) using the SHARAQ spectrometer. The other experiment was the β-decay measurement using the ZeroDegree spectrometer. These
two experiments showed that the time-stamping system is very useful. This system is expected to be usedin various experiments at RIBF in the future.

User
FPGA

4 NIM Outputs

References
Fig. 3. VME version of LUPO.

oscillator is capable of achieving a frequency accuracy
on the order of 10−6 , the clock-count diﬀerence between diﬀerent modules will be 100 counts within 1
second. In order to obtain measurements that are coincident to within 10 ns, an external clock should be
used to synchronize the modules. Usually a 25-MHz
external clock is used to transmit the clock signal togeneric NIM circuits; however, if the bandwidth of thetransfer path is suﬃciently high, a 100-MHz external
clock without DLL can be used. Using the trigger signal, the counter value is determined and stored in the
FIFO memory. The FIFO is constructed with builtin FPGA block RAM, and can store upto 1024 timestamps with 48-bits-deep. A clear signal is used asa timing reference, and it resets the counter value to
0. For the timing synchronization, two signal lines forthe external clock and for the clear signal are required.
The selection of the internal and external clock can beswitched by a CAMAC/VME command.

- 223 -

1) G. Wittwer et al.: 14th IEEE-NPSS Real Time Conference 2005.
2) P. Moritz: GSI Scientific Report, 64 (2006).
3) H. Baba et al.: RIKEN Accel. Prog. Rep. 41, 155(2008).
H. Baba et al.: IEEE Nuclear Science Symposium Conference Record 2008, 1384 (2008).
4) K. Miki et al.: in this report.

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Development of data acquisition system for short-time decay byusing Flash ADC
K. Morimoto, D. Kaji, H. Baba and F. Tokanai∗1[GARIS, short life decay, DAQ, super heavy element, production and decay]
A data acquisition (DAQ) system has been upgradedfor super heavy element research performed using theGas-filled Recoil Ion Separator (GARIS). In order tomeasure the very short lifes (0.1-10 µs) of α decays andspontaneous fission, an additional signal digitizer has
been installed in the original system.
Super heavy elements studied by using GARIS1) andGARIS-II2) , especially in the heaviest region on the
nuclear chart, may have a very short life. The original
GARIS readout electronics cannot separate sequential
decays that occur at intervals shorter than 5 µs becauseof the pileup in the shaping amplifier. The shaping
time is set at 2.5 µs in order to maintain good energy
resolution. We modified the original readout system byusing the Flash ADC (FADC) so that it can be used
to detect shorter decay intervals.
Figure 1 shows the configuration of the system. The
system consists of the original GARIS readout electronics and the newly added pulse shape acquisition(digitization) part. The original GARIS DAQ system
consists of preamplifiers, shaping amplifiers, and peaksensing ADCs, which are connected to the positionsensitive silicon strip detector (PSD) mounted in the
focal plane of the GARIS. The front-side anode of the
PSD comprises 16 resistive strips with a pitch of 3.75
mm. The hit position can be determined from thecenter of gravity of the pulse height in each strip.
Preamplifiers and FADC (SIS-3301 100 MHz 14 bit)are added to the readout on the rear side of the PSD.
The signal shapes obtained from the rear-side preamplifier are digitized over a period of 20 µs at 50 ns intervals. The decay energies can be obtained from thepulse hight E1 for mother nuclei and E2 for daughter,and the decay time δt can be obtained by analyzing
the digitized pulse-shape data. The system can distinguish between two fast sequential decays if the timeinterval between them is longer than 0.1 µs.
This system was used in experiments3) to search fora new isotope 234 Bk in the reaction 197 Au(40 Ar,3n).
These experiments were performed by using (1)GARIS + PSD mounted on the focal plane and (2)a combination of GARIS, a gas jet, and MANON4) . A
total of 119 decay chains were observed; all these decay
chains were assigned to subsequent decays from 234 Bk.
218
Ra and 214 Rn, which have very short life times (15.6µs and 0.27 µs, respectively) were contained in the decay chains. Sequential fast decay of these isotopes wasobserved in the digitized preamplifier signal. Figure 2∗1shows an example of α decay of 218 Ra (E1) and 214 Rn(E2). The energies and decay times can be clearly seenin the obtained data. Detailed analysis of the system
performance is in progress.
References
1) K. Morita et al.: Eur. Phys. J. A21, 257-263 (2004).
2) D. Kaji et al.: RIKEN Accel. Prog. Rep. 42, 179 (2009).
3) D. Kaji et al.: RIKEN Accel. Prog. Rep. 43, (2010) .
4) H. Haba et al.: J. Nucl. radiochem. Sci. 8, 55 (2007) .

Department of Physics, Yamagata University- 224 -1
















ȴ䡐


䠎

Pulse heightFig. 1. Signal processing diagram of the newly developed GARIS data aquisition system.

E1

Δｔ

E2

E2

E1
Δt
t

Fig. 2. Preamplifier signal for the sequential α decay of 218 Ra and 214 Rn

2- 225 -





 












RIKEN Accel. Prog. Rep. 43 (2010)

Simple multichannel DAC, ADC, and interface for remote control
from multiple computers
M. Wada and P. Schury∗1[DAC, ADC, Serial Peripheral Interface]∗1

Institute of Physics, Tsukuba University

The ADC card contains a 24-bit Σ-∆ ADC chip
(LTC2449 from Linear Technology) with eight diﬀ erential input channels (or 16 common mode input channels) and a precision reference voltage chip (MAX6350
from Maxim Integrated Circuit). Voltages ranging
from � 0.3 V to +5.3 V are acceptable for all input
pins of the ADC. To measure negative voltage inputs,
two instrumentation ampliﬁers (LT1107 from Linear
Technology) are mounted on this card. It also hassome peripheral circuits for an on-board temperature
sensor and two high voltage dividers. The card has onboard dropper voltage regulators (LM317, LM337) for
stable- and low-noise power supplies for the precision
ADC chip. During the test measurement of this card,
the noise levels for the maximum acquisition period of
120 ms was found to be below 1 µV (Fig. 2).
The isolated SPI distribution card (Fig. 3) accepts
a single SPI input and 3-bit digital inputs in orderto deliver four independent SPI channels, which canbe connected to the ADC and DAC cards. Each SPI
output channel is electrically isolated by an ISO7241
digital isolator chip from Texas Instruments. In thisway, all the DAC or ADC cards can be isolated fromeach other. Usually, the SPI bus is logically shared bymultiple devices, and a CS (Chip Select) signal selects
an active device on the bus. In the present design,
all signals are gated by CS in order to avoid any noisepropagating from the digital signals when other devices
are active.
We use two types of interface cards for the SPI in-

Event Number

Physics experiments often require control of many
devices and measurement of many experimental conditions. For example, in our multireﬂection time-ofﬂight mass spectrograph1) , tens of independent highprecision high voltages have to be precisely controlled,
and the actual voltages applied to the electrodes shouldbe accurately measured in order to ensure a high performance of the spectrograph. Usually, such data areproperly monitored and manipulated by computers byusing analog-to-digital converters (ADC) and digitalto-analog converters (DAC) for sophisticated feedback
control. We have been using commercial PCI-bus interface cards with an industrial PC running undera real-time Linux operating system as well as National Instruments interface cards which can be conveniently used with LabVIEW software, for our RF ion
guide experiments2) . However, these commercial interface cards do not always satisfy our demands, especially when we need more input/output channels, lower
costs, more compactness, or a higher performance thatis better than that of commercially available solutions.
Many low-cost discrete chips which can satisfy our experimental requirements, are readily available. Earlier,
it was rather complicated to handle bulk chips in actual
experiments; however, modern chips have standard interfaces such as Serial Peripheral Interface (SPI), in
which all functions are integrated onto a single chip.
Evaluation kits of these chips are often available that
help us for developments.
Simple DAC, ADC, and isolated SPI distribution
cards for general purpose use in experimental devices,which can be connected to host computers via tinycommercial SPI interface cards having ethernet or USB
connections were developed in-house. Figure 1 showsa block diagram of the method.
The DAC card has a 32-channel 16-bit DAC chip
(AD5372 from Analog Devices) and four 16-pin connectors for direct output. This output range is programmable within ±10 V by software as well as by
the reference voltage. The DAC board is also capableof summing two outputs to form a single output with
diﬀ erent gain; this is done by a precision operational
ampliﬁer (OPA4117). Therefore, a virtual 23-bit DAC
can be used, although its absolute accuracy is limitedby the quality of the reference voltage and the noise
and temperature dependence of the related circuits.
The digital interface of the card is SPI and it requires
power supplies of ±12 V and +5 V.

Measured Voltage [μV]

Fig. 2. Histogram of the data measured by LTC2449 ADC
when a diﬀerential input pair was connected to theground and the acquisition period was 120 ms. The
standard deviation of the noise was deduced to be 0.34
µV.

- 226 -

8ch out

8ch out

SPI

reference

SPI

DAC
AD53728ch out
amp

USB

Ethernet

Linux-RTAI

amp 4ch out

SPI

4ch out

Single board PC

amp

ADC card
Voltage
Regulators

Temp.

8ch outamp

4ch out

ref.
vol.

ADC
LTC2449
amps

analog inputs

4ch out

SPI

Isolator chips

SPI

SPI

Nano
Technologies

SPI

USB

Miniboard

Decoder, Gate Chips

SPI

SPI

Ethernet

RAS
NC100

DAC card

SPI Distributor

RNC-201X

Voltage Divider

Fig. 1. Block diagram of the DAC, ADC, SPI interface cards, and peripheral devices. The thick boxes
indicate in-house developments.

terface to a computer. One is an Ethernet-SPI interface card (RNC-201X from Sysmex-RC), which easilyinterfaces with a network device. Any host computers using the TCP/IP protocol can communicate withany SPI devices via this card. A simple combination of
the DAC card and the RNC-201X acts as a networked
multichannel DAC device. A drawback of this interface card is that the network capability is limited by
the “protocol-on-a-chip” design. For example, only asingle TCP connection is allowed at a time. If multiple host computers intend to connect to a device, it
becomes diﬃcult to arbitrate in an eﬃcient manner.
Another particular problem faced in the case of the
RNC-201X card is that the SPI communication withan analog chip is half-duplex. Many ADC chips suchas LTC2449 can be programmed while simultaneously
reading the converted data if the SPI communication
is full-duplex. Therefore, half-duplex operation could
limit the maximum performance of the ADC.
The other SPI interface card we use is a USB-SPI interface card (Miniboard from Nano River Technology).
It is a simple USB 1.1 device that can be connected toa variety of computers. The control program using

this USB device is based on the standard open-source
library LibUSB and an upper-level Application Programming Interface (API) library written in C++ thatis provided by the manufacturer. We can use this USB
interface card directly from a host computer; however,
we wish to use it as a network device. Therefore, we
add one more interface layer between the device andthe host computer by including a single-board industrial PC. The PC is operated by a variant of real-timeLinux, Linux-RTAI. Using such a standard operating
system ensures a versatile network capability.
The real-time Linux operating system has been usedin our data-acquisition systems and remote-control
systems for many years. Among numerous useful functions of the real-time operating system, we use thesemaphore function for mutual exclusion of resources
for the present purpose. A versatile network server
program library described in the Stevens’ textbook3)
is used for the device. It permits multiple TCP connections from diﬀ erent processes or from diﬀ erent computers. In such cases, mutual exclusion is essential for
hardware devices or critical data in order to avoid conﬂicts.
The analog interface cards and related commercial
interface cards that were developed in-house allow us
to build versatile control/monitor setups with very low
cost-performance ratios, while building sophisticatedfeedback systems with relatively less eﬀ ort. We will
initially use these devices with the precision high voltage supplies of our mass spectrograph.
References
1) P. Schury et al.: RIKEN Accel. Prog. Rep. 42 189(2008).
2) K. Okada et al.: Phys. Rev. Lett. 101, 212502 (2008).
3) W. R. Stevens: “Unix Network Programming”, Prentice
Hall, New Jersey (1990).

Fig. 3. Isolated SPI distribution card.

2- 227 -

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Installation of MuTRG-MRG and DCMIF
and Conﬁrmation of Stable Operation during Data Acquisition
K.R. Nakamura,∗1 Y. Fukao, T. Mibe,∗2 I. Nakagawa, N. Saito,∗2 A. Taketani,for the PHENIX MuTr FEE Upgrade Group[nucleon spin, W-boson, polarized parton distribution, electronics, trigger]
For the study of the sea-quark polarization in a nucleon, measurement of the single-spin asymmetry in
W boson production in a 500-GeV polarized protonproton collision is planned at PHENIX1) . A W boson
is identiﬁed by the high-momentum muon from the decay. For the eﬃcient detection of W bosons, the readout electronics of the PHENIX muon tracking chamber(MuTr) must be upgraded so that a new trigger system
can be mounted. This trigger system quickly measuresthe coarse radius of the track curvature by using the
MuTr digitalized hit information and selects only thehigh-momentum track2) .
The key components in this upgrade are two
back-end electronic devices: a data-merging board(MuTRG-MRG) and an interface board for the datacollection module (MuTRG-DCMIF). MuTRG-MRG
receives the MuTr digitalized hit data from the frontend electronic device called ampliﬁer-discriminatortransmission board (MuTRG-ADTX) and transmits
reformatted data to Local Level-1 trigger board (LL1).
MuTRG-DCMIF, on the other hand, receives the samedata that MuTRG-MRG sends to LL1 when a trigger
is ﬁred and sends the data to the data-collection module (DCM). MuTRG-MRG also controls the MuTRGADTX remotely. The functions and requirements of
MuTRG-MRG and MuTRG-DCMIF are described indetail elsewhere3) .
For the trigger system, 64 MuTRG-MRG boards and
8 MuTRG-DCMIF boards are necessary. These boards
were developed and evaluated during 2007 and 20084) ,and they passed quality assurance tests at KEK.
During the 2009 RHIC collision period (from Feb
to Jun 2009), half the number of MuTRG-MRG and
MuTRG-DCMIF boards (32 + 4), corresponding to
one half of the MuTr acceptance, were installed. These
modules were set with a practical conﬁguration, but it
was ensured that the MuTr hit data was not sent to
LL1, and data was acquired with the PHENIX DAQ
system. In this long-range operation, instability wascaused by a few minor errors. After careful investigations, we concluded these errors are mainly due to loose
connection between the LAN cables and the connectors. Thus, we plan to improve the stability by replacing these connectors. The slow control system used for
MuTRG-ADTX functioned appropriately during the∗1∗2

Kyoto University, Kitashirakawa-Oiwake, Sakyo, Kyoto,606-8502, Japan
KEK, Tsukuba, Ibaraki, 305-08011, Japan

operation. The data accumulated by MuTRG-MRG
and MuTRG-DCMIF were analyzed for evaluating theperformance of the trigger system5) .
The rest of MuTRG-MRG and MuTRG-DCMIF
boards were installed during the 2009 RHIC shutdown period. The stable operation of these modules
was conﬁrmed with the PHENIX stand-alone DAQ
for MuTr. With this installation, the installation of
MuTRG-MRG and MuTRG-DCMIF boards was completed. Figure 1 shows the complete setup of the backend electronics. In addition to this installation, a GUI
software for the steady and smooth control of MuTRGMRG and MuTRG-DCMIF was also developed.
In summary, we have completed the installation of
MuTRG-MRG and MuTRG-DCMIF for the new trigger system. These modules are ready for the next 500GeV proton-proton collision in the RHIC.

Fig. 1. The installed MuTRG-MRG and MuTRG-DCMIF
boards.

References
1) G. Bunce, N. Saito, J. Soﬀer, W. Vogelsang: Ann. Rev.
Nucl. Part. Sci. 50, 525 (2000).
2) I. Nakagawa et al.: RIKEN Accel. Prog. Rep. 43 (2010).
3) K.R. Nakamura et al.: RIKEN Accel. Prog. Rep. 41(2008).
4) T. Mibe et al.: RIKEN Accel. Prog. Rep. 42 (2009).
5) Y. Fukao et al.: RIKEN Accel. Prog. Rep. 43 (2010).

- 228 -

1

III. RESEARCH ACTIVITIES II(Material Science and Biology)

1.

Atomic and Solid State Physics (ion)RIKEN Accel. Prog. Rep. 43 (2010)

Single-Event Transient Test Results of Control IC of Point-of-Load DC/DC Converter
Y. Yano*1, N. Ikeda*1, S. Kuboyama*1, H. Ohzono*2, O. Shimada*2, H. Otomo*2, H. Mutoh*2, T. Kambara*3, and M. Kase*3
Recent space syste ms use high-s
peed and hi
ghperformance electronic devices such as a M icro Processing
Unit (MPU) and Field Programmable Gate Ar ray (FPGA).
These devices req uire l ow-voltage a nd high-current i nput.
When power is supplied through long wires, their resistancecauses a voltage drop at the input of t hese de vices. As aresult, t he i nput vo ltage could b e below t he sp ecification
limit. This problem can be solved by using a Point-of-Load(POL) DC/DC conv erter, which is installed near th ese
devices. A P OL c onverter co nsists o f a co ntrol IC a ndseveral c omponents, a nd t he pe rformance of t he P OL
converter depends greatly on the control IC.
Figure 1 shows an example of the output voltage drop in a
POL converter; this is du e to a Sin gle-Event Transient(SET) at the control IC. An SET is a temporal variation in
the output voltage or current of the circuit due to a passage
of a heavy ion from deep space through a sensitive device.
A l arge c hange i n v oltage or cur rent ca used by S ET c ould
cause m alfunction or data er ror t o t he co nnecting devices.
Therefore, we pe rformed he avy-ion i rradiation t est using
the cyclotron at RIKEN to i dentify which part of the circuit
is sen sitive to SET . Kr ions were used; energy, Li nearTransfer Energy (LET), and range of Kr ion in Si were 977
MeV, 29.2 MeV-cm2/mg and 124 µm, respectively.
Heavy Ion Incidence
Output voltage drop

Vout
1V/div

Effect of SET

OUTH
5V/div
OUTL
5V/div

10μsec/div

Fig.1 SET observed at the analog block of the control IC
during Kr irradiation at RIKEN.
The co ntrol IC i s c omposed of se veral blocks suc h a s
analog and logic circuits, shown in Figure 2. We covered apart of the block with a s mall piece of m etal duri ng
heavy-ion i rradiation. B y c overing di fferent a rea a ndcomparing the responses, we can identify the bloc k that i ssensitive to SET . SET cro ss sectio n is calcu lated as thereciprocal of the average ion fluence i n a si ngle SET
occurrence. T his cross section corre sponds to t he size of
the SET-sensitive area and is a good index that can be used
to determine SET sensitivity.
First, we performed irrad iation tests to find th e m ost
sensitive element in the IC. The result showed that the
＊1
＊2
＊3

Japan Aerospace Exploration Agency
Ryoei Technica Corporation
RIKEN

smallest SET cross section was obse rved whe n the anal og
block was covered; this indicates that the element containedin the analog block is the most sensitive to SET.

Fig.2 Block diagram of control IC
The cross section of t he analog circuit was approximately
1,000 µm 2 under the irra diation condition for our study.
This is a c onsiderably la rge a rea, and a MOSFET in th e
voltage reference circuit ( Vref) is th e only ele ment th at h as
such a la rge a rea. Therefore, we c oncluded th at this
MOSFET is the origin of the SET in most cases.
Then we considered how the output voltage drop shown in
Figure 1, occurred. V ref is a very im portant circu it that isconnected to various circ uits in the IC. Figure 3 shows the
SET sen sitive circu it in t he an alog block. We speculated
that the pr ocess by w hich V ref af fects t he output voltage
drop is as follows (see Figure 4):
1. A hea vy i on st rikes t he MOSFET i n Vref, and th e Vref
voltage drops (Fig.3).
2. An er ror amp lifier d etects a c hange in th e ou tput
voltage with reference to V ref. The voltage drop in V ref isalso detected as an error, shown in Figure 4 as “VER“.
3. A Pulse-Width Modulation (PWM) signal is generated
by com paring V ER with Oscillato r (OSC). Th erefore,
PWM duty temporarily decreases due to the VER drop.
4. T he o utput vol tage drops as resul t o f t he t emporary
decrease in PWM duty.
R

R

C

VER

－
＋

R

Error AMP
Vref

Fig.3

－

PWM

＋

OSC

SET-sensitive circuit

Fig.4 Effect of SET

We ha ve cl arified t hat t he d rop i n t he output voltage
occurred in the V ref circu it an d th at th e M OSFET was themost SET -sensitive ele ment. Th e resu lts were co nsidered
for the redesign of the IC to achieve a better SET tolerance.

- 229 -

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Feasibility of RI-beam-based wear analysis for industrial materials
T. Kambara, A. Yoshida, Y. Yanagisawa, N. Fukuda, D. Kameda, T. Kubo, H. Haba, A. Nagano,∗1
and R. Uemoto∗1
Parts of machines such as internal combustion engines are generally exposed to severe conditions such as
harsh chemical environments, high temperature, andmechanical friction. Hence, the wear and corrosion of
the material determine the reliability and lifetime ofthe parts. Recently, new materials and surface treatment techniques for such mechanical parts have beendeveloped in industries for achieving better eﬃciency
and safety, low energy consumption, and long product lifetime. For such developments, it is crucial tocarry out real-time monitoring of the wear and corrosion of the mechanical parts of machines operating
under various conditions. One method of wear analysis involves incorporation of radioisotopes (RIs) in thematerial and detection of the γ rays emitted from themechanical parts or the wear particles mixed with thecirculating lubricant; the analysis of the γ rays fromthe mechanical parts helps monitor the degradation of
the material. A conventional method to produce RIs
in a material involves irradiation of protons from anaccelerator to induce nuclear reactions in the material.
However, this method requires high-dose irradiation of
the proton beam and hence causes radiation damage tothe material, and for some elements, RIs with suitably
long lifetimes and decay modes cannot be produced bysuch reactions.
An alternative method has been proposed1) to overcome this problem; in this method, RI nuclei are incorporated into the material from an external source as
an RI beam, instead of activating the nuclei in the material by particle irradiations. In this case, a proper RI
nuclide can be selected, irrespective of the compositionof the material, and radiation damage is signiﬁcantly
reduced because the number of incident particles issmall. The depth proﬁle of the RI distribution can becontrolled by controlling the energy of the RI beam.
We evaluated the feasibility of this method at
RIKEN by performing an RI implantation experimentat the RIPS to measure the eﬃciency and depth proﬁle of the implanted RI. We selected 22 Na (T1/2 = 2.6y) as a tracer nuclide since its lifetime is suitable forwear analysis and it emits γ rays eﬃciently; 22 Na undergoes β + decay to aﬀord two 511-keV γ rays, whilea 1275-keV γ ray is emitted from the daughter 22 Ne.
In this experiment, a 63-MeV/nucleon 23 Na beam
was accelerated by the RILAC and the RIKEN Ring
Cyclotron and was led to the RIPS with a maximum
intensity of 300 pnA. The primary beam was madeincident on a production target, a 1.5-mm-thick Be
foil, and the secondary 22 Na beam was separated and∗1

guided to the F3 target position. The purity of 22 Na
in the beam was approximately 85%. At the F3 target
position, the RI beam was made to pass through a setof energy degraders with adjustable and ﬁxed thicknesses so that it could be stopped in a test sample,
which was a stack of Al foils.
After 14 h of implantation with the primary beam
having the maximum intensity, the γ rays emitted fromthe sample were analyzed using a Ge detector. Figure
1 shows the γ-ray spectrum recorded approximately
4.5 h after the implantation. The measured radioactivity of 22 Na was approximately 25 kBq, which corresponded to around 3 × 1012 nuclei in the sample. The
yield eﬃciency of the implanted 22 Na was estimatedto be around 2.8 × 106 /s per 10 pnA of the primary23
Na beam. This value was in good agreement withthat calculated using the RI-beam production rate andthe transportation eﬃciency of the RIPS. The depth
distribution of 22 Na, estimated from the radioactivity
measured at each Al foil in the stack, ranged between
50 µm and 150 µm, with the maximum at about 100µm from the surface. The γ-ray spectrum also showed
the presence of 24 Na (T1/2 = 15 h), whose radioactivity was 660 Bq; this nuclide was probably produced by
nuclear reactions between the Al nuclei in the sample
and the 22 Na beam.
The present results show that RI-beam implantation
with the RIPS is feasible for wear analysis of mechanical parts. Technical and operational improvements
must be carried out so that the radioactivity of theimplanted 22 Na increases to 1 MBq.

Fig. 1. γ-ray spectrum of the implanted sample.

References
1) P. Fehsenfeld, C. Eifrig, and R. Kubat: Nucl. Phys. A
701, 235c (2002).

S.H.I. Examination & Inspection, LTD.

- 230 -

1

RIKEN Accel. Prog. Rep. 43 (2010).

In-beam Mössbauer experiment on stress-induced iron diffusion in silicon
K. Suzuki,＊1 Y. Yoshida,＊2 Y. Kobayashi, H. Ueno, K. Yukihira,＊2 K. Hayakawa,＊2 M. Mihara,＊3 W. Sato,＊4 A. Yoshimi,
T. Nagatomo,＊5 Y. Ichikawa, T. Furukawa,＊1 T. Inoue,＊1 Y. Hasama,＊1 H. Iijima,＊1 M. Tsuchiya,＊1 H. Hayashi,＊1 Y. Ishii,＊1
T. Nanao,＊1 and K. Asahi＊1

Tokyo Institute of Technology
Shizuoka Institute of Science and Technology
Osaka University＊4
Kanazawa University＊5International Christian University
＊1
＊2
＊3

120

befor applying stress

0 MPa

100

Normalized counts

In-beam Mössbauer spectroscopy involving Coulombexcitation and recoil-implantation techniques has previously
been applied to the study of dynamical processes of
impurity diffusion in metals and semiconductors 1, 2). The
final lattice locations of the probe atoms were determinedby observing hyperfine interactions between the nuclear
probes and the electrons surrounding them in solids.
Furthermore, the jump frequencies corresponding to cage
motion of interstitial 57Fe in -Zr 1) and long-range
diffusion of interstitial 57Fe atoms in Si 2) were observed at
50 K and 600 K, respectively. Recently, at the RIKEN RI
beam facility, in-beam Mössbauer experiments on 57Mn/57Fe
impurities in silicon have been performed at temperatures
up to 1200 K by using nuclear fragmentations and by
applying the implantation technique3, 4). In theseexperiments, relaxation due to interstitial 57Fe jumps andsubsequent defect reactions with vacancies that result in theformation of substitutional 57Fe atom have been directly
observed and compared with a kinetic model that includes
defects and the 57Fe probes. The purpose of the present
experiment is to study stress-induced diffusion of the ironatoms in silicon under an external stress.
An n-type float zone silicon wafer was cut into a
rectangular disk of dimensions 20 × 10 × 0.53 mm and was
fixed between a pair of ceramic blocks in a tensile testingmachine. The tensile testing machine has been developed inorder to apply external stresses of up to 20 MPa. By
applying a compressive stress along the [011] direction, theSi wafer was bent, and this resulted in a tensile strain on
one side of the wafer and compressive strains on the otherside. A pulsed 40Ar beam with an energy of 4 MeV/u and a
period of 1 s was obtained from the AVF cyclotron andwas transmitted to a thin 57Fe target. The 57Fe nucleus was
Coulomb-excited into the levels at 137 keV, 367 keV, and707 keV. The 14.4 keV isomers 57mFe that were populated
through the de-excitation of these levels emerged from thetarget and were implanted into the Si wafer. The Mössbauer
spectra of 57Fe were acquired at room temperature by using
a parallel plate avalanche counter (PPAC) when 57mFe was
implanted in the tensile region.
The Mössbauer spectra obtained for 57mFe implanted in
an n-type FZ-Si sample under external stress are shown in
Fig. 1. The spectrum obtained before applying the external

120

20 MPa

100

120

0 MPa

after removing stress

100
-2

0

Velocity [mm/s]

2

Fig. 1. Mössbauer spectra for isolated 57Fe in silicon underthe external stress after implantation. The singlet at theleft-hand side corresponds to interstitial Fe+, and atright-hand side to substitutional Fe.
stress was well fitted by two sets of Lorenz functions
representing the substitutional and interstitial Fe+,
respectively. This spectrum is consistent with the previous
result reported by P. Schwarbach2). When an external stressof 20 MPa was applied, the shape of the spectrum changed
into one presumably farmed by a broad singlet and a sharp
singlet. Although the statistical errors are not good enoughfor finer analyses, line broadening that suggests
stress-induced diffusion of 57Fe atoms. The diffusion
coefficient corresponding to the observed line width is of
the order of 10-9 cm2/s. This result is consistent with ourprevious results from the transmission Mössbauer
experiments, 5) and the value is larger than that reported forrelaxed Si by six orders of magnitude 6). Furthermore, thepeak position of the interstitial line is shifted toward thesubstitutional line. This phenomenon is explained bymotional averaging, which is considered to be due toexchange jumps of the 57Fe probes between substitutional
and interstitial sites within a time scale of the lifetime of
57m
Fe ( ~100 ns).
References

1) Y. Yoshida et al., Phys. Rev. Lett. 61 (1988) 195.
2) P. Schwalbach et al., Phys. Rev. Lett. 64 (1990) 1274.
3) Y. Yoshida et al., Physica B 376 (2006) 69.
4) Y. Yoshida et al., Physica B 401 (2007) 101.
5) K. Suzuki et al., Physica B 404 (2009) 4678.
6) E. R. Weber, Appl. Phys. A 30 (1983) 1-22.

- 231 -

RIKEN Accel. Prog. Rep. 43 (2010)- 232 -

RIKEN Accel. Prog. Rep. 43 (2010)������������������� ���� ������ �� �������� �� ������� †E. Yagi,*1 K. Sakuma,*2 N. Higami,*2 S. Hagiwara,*2 K. Mori,*2 M. Yoshii,*2 S. Koike,*3 T. Hayashi,*2 and K. Ogiwara
Hydrogen (deuterium)-defect interactions in metals havebeen important subjects as fundamental properties ofhydrogen and also from the technological interest in thefusion reactor materials. On the atomistic state of hydrogen(deuterium) interacting with defects, a number ofexperiments have been performed on implanted deuterium,
because implantation introduces deuterium and latticedefects simultaneously into specimens. As its lattice
location, different types of sites displaced from a tetrahedral(T) site or an octahedral (O) site, which are equilibriumsites for dissolved deuterium, have been reported fromchannelling experiments and, for the occupancy of suchdisplaced sites, different interpretations have been
proposed; trapping of deuterium by vacancies or trapping inan anisotropically distorted lattice induced by implantation.
Therefore, the state of deuterium is still in question. For
hydrogen (H), recovery of H-doped metals irradiated at low
temperatures has been investigated by electrical resistivity
and the positron-lifetime measurements, but the lattice
location has not been studied, because a channelling method
to locate hydrogen was not available despite its usefulness.
Since the behaviour of hydrogen is not necessarily thesame as that of deuterium as recognized in the difference ofa phase diagram in the metal-H (D) systems, studies onhydrogen are indispensable. Therefore, in the present study,
the effect of ion-irradiation on the lattice location ofhydrogen dissolved in Nb, NbH0.023, is studied by thechannelling method utilizing a nuclear reaction 1H(11B,a)aa with a 11B beam of about 2 MeV, which has beendeveloped to locate hydrogen dissolved in metals.1) In thismethod, hydrogen can be detected by measuring emitted aparticles, whose energy ranges from zero to about 5 MeV.
The specimen is a Nb single-crystal. Hydrogen wasdoped from the gas phase. The channelling analyses were
performed at room temperature for <100>, <110> and{100} channels. The yield of 11B ions backscattered by Nb
atoms and the yield of emitted a particles were measured asa function of the incidence angle y (angular profiles)
with respect to the channel direction in question by tilting
the specimen (angular scan). The irradiation was made atroom temperature with 11B+ ions of 2.03 MeV up to a doseof about 1.4×1016/cm2 at a dose rate of about 3×1011/(cm2• sec) at an angle more than 3.5° off from the channelling
direction in question, i.e., in the random direction. This
irradiation produces only Frenkel defects in the near surface
region shallower than 0.2 mm, which is probed in the†Condensed from the article in J. Phys. Soc. Jpn. 77, 124602 (2008)＊1
RIKEN and The School of Sci. and Eng., Waseda University＊2
The School of Sci. and Eng., Waseda University＊3
Department of Physics, Tokyo University of Science

channelling analysis, because the projected range ofincident 11B+ ions is 1.35 mm.
Figure 1 shows the channelling angular profiles obtained
after the irradiation. From the comparison with the profiles
calculated for 5 different types of sites as in a previous
paper,2) the lattice location of hydrogen was determined to
be a site displaced from an original T site by 0.45–0.55 Å
towards its nearest neighbour lattice point (Fig. 2). Taking
into account the results of electrical resistivity andpositron-lifetime measurements hitherto made on therecovery of electron-irradiated H-doped Nb, it is concluded
that this irradiation-induced site change of hydrogen from T
sites is due to trapping of hydrogenbyirradiation-introduced monovacancies. Hydrogen is locatedat a site displaced from one of the T sites attached to avacancy towards that vacancy. This site is completely
different from those proposed for implanted deuterium.

Fig. 1. Channelling angular profiles obtained at room
temperature after irradiation with 2.03 MeV 11B+ ions up toa dose of 1.4×1016/cm2.

Fig. 2. Atomic configuration of hydrogen trapped by amonovacancy. Hydrogen (△) is located at a site displaced
from one of the T sites (●) attached to a vacancy (□) by
0.45–0.55 Å towards that vacancy.
References

1) E. Yagi, T. Kobayashi, S. Nakamura, Y. Fukai, and K.
Watanabe: J. Phys. Soc. Jpn. 52, 3441 (1983).

2) E. Yagi, S. Koike, T. Matsumoto, T. Urai, N. Tajima, andK. Ogiwara: Phys. Rev. B 66, 024206 (2002).

- 233 -

RIKEN Accel. Prog. Rep. 43 (2010)

5 mK

6 mK

7 mK

T = 6 d1 mK

Experiment- 234 -

0.1 mmRIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Excitation spectrum of Au atoms in superfluid helium
Y. Matsuura,∗1 T. Furukawa, T. Kobayashi, A. Hatakeyama,∗3 K. Fujikake,∗1
M. Tachikawa, ∗1 and Y. Matsuo
Superfluid helium (He II) is expected to be an effective environment for determining the nuclear spins
and moments of short-lived unstable nuclei by using
laser spectroscopic method1) . We plan to measure
Zeeman splittings and hyperfine structure splittingsof atoms with unstable nuclei by the optical pumping
and laser-radio frequency/microwave double resonancespectroscopy. Atoms implanted into He II show a blueshifted and broadened excitation spectrum because of
the atomic-bubble effect in He II2) . One can take advantage of this property for the optical pumping of avariety of atomic species because it is not necessary
to fine-tune the laser frequency. The other advantage
of using He II is that highly sensitive optical detection
can be achieved since the emitted photons can be completely separated from the laser excitation light on thebasis of their wavelength because of the large difference
between the emission and excitation wavelengths. So
far, we have succeeded in the optical pumping of alkali atoms Cs and Rb3) and a group 11 element,Ag4) .
In order to achieve efficient optical pumping, the wavelength of the laser should be at the peak position of theexcitation spectrum in He II. Therefore, the excitation
spectrum of Au atoms in He II has to be measured.
The experimental setup is shown in Fig.1. The apparatus consists of a cryostat chamber (Oxford) withquartz windows, an optical detection system, and threelasers. A Au sample is placed 1 cm above the quartz
cell (70 × 70 × 70 mm3 ) that is filled with He II bytransferring liquid he by exploiting the fountain effect.

800 nm, pulse energy: 150µJ, repetition rate: 500 Hz,
pulse width: 200 fs). The generated atoms are irradiated by a UV laser pulse, which is generated by the frequency doubling of a pulsed dye that is laser pumpedby an excimer laser (wavelength: 308 nm, repetition
rate: 10 Hz, pulse width: 18 ns); this frequency doubling is achieved using a BBO crystal. We observed
laser-induced fluorescence (LIF) by sweeping the wavelength of the UV laser from 254 nm to 265 nm. In
order to maintain the phase-matching condition of thefrequency-doubling BBO crystal, we installed an autotracker (Inrad, Model: AT-II) along with the BBO
crystal. LIF was detected by a photomultiplier tube
(PMT) using a monochromator that was set to the Au
emission wavelength of 267 nm, which is close to the
S-P transition wavelength of Au in free space (267.594
nm). Additionally, we simultancously monitored thepower of the UV laser in order to normalize of thelaser power because LIF intensity is proportional tothe incident laser power. Figure 2 shows the normalized LIF intensity plotted against the UV-laser wavelength. The maximum excitation wavelength was obsened to be around 263.5 nm, with a pluse width of
2 nm. We concluded that the most efficient opticalpumping of Au atoms in He II would occur at a wavelength of 263.5 nm. In the near future, we plan to induce atomic polarization of Au atoms and determine
their nuclear moments by the optical pumping withthe laser of 263.5nm in near future.

Fig. 1. Experimental setup.
Fig. 2. Excatation spectrum of Au atoms.

At first, the solid Au sample was sputtered using
Nd:YAG laser (wavelength: 532 nm, pulse energy: 3
mJ, repetition rate: 10 Hz, pulse width: 10 ns) to produce Au clusters. Next, the clusters are dissociatedinto atoms by using a femtosecond laser (wavelength:
∗1
∗2
∗3

Department of Physics, Graduate School of Science andTechnology, Meiji University
Department of Physics, Graduate School of Science andTechnology, Tokyo Institute of Technology
Institute of Physics, Graduate School of Arts and Sciences,
The University of Tokyo

References
1) T. Furukawa et al.: RIKEN Accel. Prog. Rep. 38, 99(2005).
2) B. Tabbert, H. Günther, and G. zu Putlitz: J. Low
Temp. Phys. 109, 653 (1997).
3) T. Furukawa et al.: Phys. Rev. Lett. 96, 095301 (2006).
4) T. Furukawa et al.: RIKEN Accel. Prog. Rep. 42, 194(2009).

- 235 -

1

2.

Atomic and Solid State Physics (muon)

RIKEN Accel. Prog. Rep. 43 (2010)

Installation and beam commissioning of new multi-channel µSR
spectrometer “CHRONUS” and beam commissioning at RIKEN-RAL
D. Tomono, T. Kawamata, Y. Hirayama∗1 , M. Iwasaki∗1 , I. Watanabe, K. Ishida and T. Matsuzaki
A research project aimed at investigating various
types of matters under several extreme conditions,such as high pressure, low temperature and laser irradiation by the µSR technique1) has been underway;
the high-intensity beam at the RIKEN-RAL muon facility is begin used in this project. In order to further promote the project, the multichannel spectrometer named CHRONUS (multi-CHannel Riken muON
Universal Spectrometer) has been newly developed in
the Port-4 area; this spectrometer enables us to perform experiments in parallel by dividing the doublepulsed muon beam between Port-2 and Port-4 using
kicker magnets. On the basis of a performance feasibility test2–4) , we designed a spectrometer consistingof 606 decay positron counters, a counter mold andframe, ﬁber light guides, multianode photomultipliertubes covered with magnetic ﬁeld shields, and a newdata acquisition system.
Zero Field coilElectron/Positron counter moldTransverse Field coilLongitudinal Field coilmuon beam

Zero Field coil100

Fig. 1. Schematic illustration of the magnets and countersystem in the spectrometer.

Figure 1 shows a vertical view of the spectrometer.
All magnets had good homogeneity within a deviationof 0.1%. A pair of large longitudinal ﬁeld coils were
mounted coaxially along with the muon beam, transverse ﬁeld coils were mounted on the top and bottom,
and three pairs of zero-ﬁeld coils were wound aroundthe sample; all coils were ﬁxed in a square aluminum
frame. Fully polarized slow muons were implanted in
the sample; the muons stop at speciﬁc sites and interact with the local magnetic ﬁeld while undergoingspin precession at the Larmore frequencies. Since decay positrons are emitted preferentially in the directionof the instantaneous muon spin, an internal magnetic
ﬁeld in the sample can be measured by decay positroncounters that are mounted coaxially inside of the boreof the longitudinal ﬁeld magnet. The time evolutionof the asymmetry A(t) is written as
A(t) =

NF (t) − αNB (t),NF (t) + αNB (t)where NF and NB are the instantaneous number ofmuon decays for a total of 303 forward and backward
counter assemblies, respectively. The parameter α isa setup-dependent correction factor. The number of∗1Fig. 2. Top: typical muon decay time spectra for forward
and backward counters, as obtained by using a silver
target at H=0 and HTF =20 G; bottom: the corresponding asymmetry spectra for H=0 and HTF =20 G,
represented by closed and open circles, respectively.

segments enables us to reduce distortion of the time
spectrum caused by pile-up signals. In the period between June and the present, the above mentioned components have been assembled and installed, and a spectrometer has been commissioned using a muon beam.
A silver plate with a diameter greater than the beam
diameter was mounted at the center of the spectrometer. After an appropriate threshold level was set by themethod explained in Ref.2,3) , time spectra were measured under a transverse magnetic ﬁeld of 20 G andunder the zero ﬁeld.
Figure 2 shows the preliminary time spectra for forward and backward counters as well as the corresponding asymmetry spectra obtained at room temperature.
The background level is suppressed to less than 10−5of the number of events at the time zero. The amplitudes of the asymmetry spectra are found to be approximately 15%; these amplitudes are smaller thanthose expected on the basis of the solid angle of thecounters (20%). Further analysis is being carried out
to increase the amplitude. In addition, muonium precession was measured using a SiO2 plate in order to
conduct homogeneity test on the Helmholtz coils. An
oxygen-free copper target was used along with a heliumow cryostat to observe the temperature dependence of
the asymmetry spectra down to 5 K. These commissioning data is being analyzed in order to prove thatthe spectrometer can be used for practical µSR measurement. A remote control system for various devices
is being implemented and the operation of devices suchas a cryostat system will begin.
References

also Department of Physics, Tokyo Institute of Technology- 237 -

1) I. Watanabe et al.: Physica B 404, 993(2009).
2) Y. Hirayama et al.: RIKEN Accel. Rep.41, 195(2008).
3) D. Tomono et al.: Nucl. Inst. Meth. A 600, 44(2009).
4) D. Tomono et al.: RIKEN Accel. Rep. 42, 237(2009).

RIKEN Accel. Prog. Rep. 43 (2010)

Data Acquisition System for µSR Experiment at Port-4 of
RIKEN-RAL Muon Facility
T. Kawamata, D. Tomono, I. Watanabe, K. Ishida, and T. Matsuzaki[µSR, data acquisition system]
Presently, muon spin rotation/relaxation/resonance(µSR) experiments are carried out using a spectrometer named “ARGUS” at Port-2 of the RIKEN-RAL
Muon Facility. ARGUS is equipped with 192 plastic scintillation counters for recording timing signals
from decay positrons/electrons. The obtained signals
are digitized by time-to-digital converters (TDCs) andsaved as time histograms at each counter by the EXP
software running on a Linux personal computer (PC)1)
. The data acquisition system (DAQ) used for ARGUS consists of CAMAC modules and MACS-EXP
software running on a PC. The dead time of the DAQ
is dominated by the low data transfer rate between CAMAC and the PC, because CAMAC and the PC areconnected by the old SCSI technique. In µSR experiments, the software MACS running on a Windows PC
controls external conditions such as the temperatureand magnetic ﬁeld of the sample and controls EXP via
a communication ﬁle. The obtained histogram data
are converted to asymmetry data and analyzed usinga software WiMDA2) running on a Windows PC.
Recently, we have installed a new spectrometer
named “CHRONUS” in Port-4 of the RIKEN-RAL
Muon Facility, in order to perform µSR experiments
at a high data acquisition rate; a high-intensity muon
beam is used for the experiments. CHRONUS has 606
small plastic scintillation counters to avoide counting
losses for multiplex hits. A new DAQ system must
be installed in CHRONUS for acquiring and analyzinglarge amounts of data from the 606 counters.
The hardware conﬁguration of the DAQ system issuch that the signals from 606 plastic scintillation
counters are converted to digital signals by 38 16channel VME discriminators (CAEN V895). Then,the digital signals are converted to time information by
ﬁve 128-channel VME multihit TDCs (CAEN V1190).
The data stored in the output buﬀers of the TDCs
are transferred to a Linux PC via a VME-PCI opticallink bridge (CAEN V2718). Data transfer can be completed before the next spill because of the high datatransfer rate of V2718. Moreover, no beam loss occurs during data transfer because the output buﬀer of
the TDCs can be read out independent of the data acquisition process. Two VME-USB2.0 bridges (CAEN
V1718) are used to control the discriminators.
Because many users carry out µSR experiments, itis necessary that the user interface of the DAQ system is the same as that of the DAQ system of ARGUS, to avoid confusion. Therefore, we replaced only

Fig. 1. Diagram showing the relation between the user andthe software and processes in the new data acquisition
system used for µSR experiments. The rounded rectangles show the processes managed by the KiNOKO
system.

EXP with a new DAQ system, KiNOKO,3) which isa general-purpose DAQ system based on the distributed object technology and written in C++. Basically, the KiNOKO system consists of seven processes;
controller, collector, analyzer, buﬀer, recorder, viewer,
and logger. KiNOKO can be customized by the addition, removal, or realignment of these processes and/or
customized processes. A customized process is built by
the inheritance of the classes prepared by the KiNOKO
system. Figure 1 shows the customized Kinoko systemused for µSR experiments. In this system, the raw dataacquired by the collector from the TDCs are analyzed
by the customized analyzers (TDC analyzer, multiplicity analyzer, etc.) and transferred to the buﬀer. The
viewers and customized recorders (raw data recorder,
histogram recorder, etc.) obtain data from the buﬀer
for online display and data storage, respectively. Test
experiments reveal that the DAQ system can successfully transfer data without data loss. We plan to add
a new process communicator to facilitate remote operations from MACS via a communication ﬁle, similar
to that used for EXP. We are debugging the communicator at present and are planning to complete theinstallation of this DAQ system in the near future.
References
1) S.N. Nakamura and M. Iwasaki: Nucl. Inst. and Meth.
A 388, 220 (1997).
2) F.L. Pratt: Physica B 289-290, 710 (2000).
3) S. Enomoto: “KiNOKO - A General-Purpose Data
Acquisition System”, http://www.awa.tohoku.ac.jp/˜sanshiro/kinoko-e/index.html (28/Jan/2010).

- 238 -

RIKEN Accel. Prog. Rep. 43 (2010).

Development of a new Lyman-α laser for generation of ultraslow muonsK. Yokoyama, N. Saito, O. A. Louchev,＊1 K. Ishida, M. Iwasaki and S. Wada
Development of the high intensity, low energy muon
(LE-µ+) source is of importance in various fields such as
particle, atomic, and condensed matter physics because of
its narrow energy spectrum and low temperature. Bakule etal. have been developing a pulsed LE-µ+ source at the
RIKEN-RAL muon facility in UK by photo-ionizing
muonium, and obtained an overall generation efficiency of
3×10-5, generating ~15 µ+/s, which may not be sufficientfor practical uses1). To improve the yield, it is crucial todevelop a high-intensity Lyman-α (Ly-α) laser light (122nm) for exciting muonium from the 1S to 2P state, before
ionization by another UV light at 360 nm. We are currently
developing a new Ly-α laser system that can generate ~100µJ/pulse, which is 100 times the energy generated by theexisting laser system at RIKEN-RAL.
Since no optical crystals are transparent at the
wavelength of the Ly-α line (ωLy-α), nonlinear opticalprocesses in gaseous media have been used to generate
vacuum UV light. Here, we use the two-photon resonant
four-wave mixing process in Kr gas. As shown in Fig. 1, ω1(212.55 nm) excites a Kr atom through the two-photon
absorption process, then ω2 (815~850 nm) generates ωLy-α
by difference frequency generation. Since Kr has negative
dispersion at ωLy-α, it is necessary to add Ar gas, which has
positive dispersion at ωLy-α, so that the gas mixture satisfies
the phase-matching condition. It is known that by thismethod, relatively high conversion efficiency (~10-4) andtunability (121.5~122.2 nm) can be achieved.
To achieve ωLy-α with 100 µJ/pulse, it is necessary to
generate ω1 with a pulse energy as high as 100 mJ because
the conversion efficiency is proportional to P12P2, where P1
and P2 are the laser power for ω1 and ω2, respectively. For
this purpose, we use the Nd:GdVO4 crystal, which wasrecently developed by the authors2). This crystal has a gain
spectrum centered at 1062.9 nm with ~2 nm bandwidth,
thus the crystal can be used as a gain medium at 1062.75
nm, for which the fifth-order harmonics is 212.55 nm.
Therefore, the crystal is considered as an ideal gain medium
for a fundamental wavelength of ω1. The seed laser for thefundamental wavelength is a distributed-feedback laser
diode (DFB-LD) that gives narrow linewidth (~2 GHz),

Fig. 1 Energy diagram of four-wave mixing process in Kr.
＊1

MegaOpto Co., Ltd., Saitama, Japan

Fig. 2 Laser system for generation of ω1.
which is important because the energy of two-photon
absorption of ω1 is well defined. Since it is estimated that
we require ~1 J/pulse of the fundamental wavelength toobtain ω1 with 100 mJ/pulse (10 %), we have to build a
couple of amplification stages, as shown in Fig. 2. The
amplified fundamental is converted to ω1 by a nonlinear
frequency-conversion system. We use an LBO (lithium
borate) crystal for the second harmonic generation and
CLBO (Cesium lithium borate) crystals for the fourth andfifth order harmonic generation to achieve 10% conversion
efficiency. The CLBO crystal has high conversion
efficiency and relatively high damage threshold at ω1,
making it an ideal crystal for long-term stable operation.
For the ω2 laser, we use the DFB-LD as an oscillator in amanner similar to the case of ω1, and then we amplify it by
optical parametric amplification using an LBO crystal. As
in the case of ω1, our goal for ω2 is also 100 mJ/pulse. Thisshould not be very difficult because technologies are moreestablished for the wavelength range unlike the case of ω1.
ω1 and ω2 are made collinear and focused on a gas cell
containing the Kr/Ar mixture to generate ωLy-α.
Unfortunately, there have been no systematic studies so far
on the conversion efficiency of ωLy-α as a function ofparameters such as the ratio of partial pressures of the gases,
absolute pressure, laser intensity, and laser spatial profile.
We need to measure fundamental optical parameters such as
the third-order susceptibility of Kr when the atom is in an
excited state, to simulate the best conditions for generating
ωLy-α. To generate ~100 µJ/pulse of ωLy-α with 100 mJ/pulseof ω1 and ω2, the conversion efficiency should beapproximately ~10-3, which makes this development itself
already challenging. We have started building the laser
system and performing simulations. We aim to achieve theabove-mentioned goals during the second half of 2010 andinstall the Ly-α laser at RIKEN-RAL by early 2011 for theexperiment on slow-muon production.
References
1) P. Bakule et al.: Nucl. Instr. Meth. B 266, 335 (2008).

2) T. Ogawa et al.: Opt. Lett. 28, 2333 (2003)- 239 -

RIKEN Accel. Prog. Rep. 43 (2010)

Studies on Muon Spin Relaxation of n-Si Conduction Electrons
Produced in p-GaAs Overlayer by Lasers and Injected by Electrical Method

E. Torikai1, K. Nagamine2, 3, I. Shiraki1, K. Shimomura３, R. Kawakami2, H.W.K. Tom2, P. Bakule４, F.L. Pratt４, K. Ishida, K. Ohishi, K.
Yokoyama2, Y. Matsuda5, K. Takeda6, T. Ujihara6, T. Saka7, andT. Kato7

It has been proposed that spin-dependent exchange
scattering of the polarized electron in ortho muonium(ortho-Mu, μ+e-, a bound state of a positive muon and anelectron in which the spins of both particles aligned in thesame direction) can help to detect the conduction electron
spin polarization (CESP) in semiconductors [1]. Recently a
proof-of-principle experiment on this muon method was
successfully carried out in a strain-free n-type GaAs
(containing 3×1016 cm-3 Si) by measuring the change in theμ+ polarization corresponding to the change in thepolarization direction under both longitudinal fields (LF)
and zero field (ZF) [2, 3].
The production and detection of CESP in Si is known
to be difficult because of an indirect band-gap and a small
spin-orbit interaction. There exists only a limited
knowledge on hot electron injection through ferromagnetic
layer grown on Si[4, 5]. The proposed muon method is
expected to be most effective for detecting CESP in Si.
Here, the behavior of the un-polarized conduction electron(CE) found during the course of the CESP studies isreported.
The experiment was conducted at the RIKEN-RAL
Muon facility located at ISIS of Rutherford Appleton
Laboratory. A pulsed 4-MeV μ＋ beam was used. Tunable
laser light with a wavelength of around 815 nm energy of
1.52 eV, and a repetition frequency of 25 Hz was generated
by using an OPO system pumped by a 355-nm Nd:YAG
laser. The linearly polarized laser output is converted to100% circularly polarized (CP) light to illuminate thesample. The average power of the laser was nearly 1.5
mJ/pulse, which corresponds to 6×1015 cm-3 photons/pulse.
The sample used in the present measurement (Fig. 1)
was the same as that used in the KEK experiment [1]. Here,laser excited CE in a p-GaAs (0.14 μm in thickness) layer
was electrically injected into an n- Si substrate (290 μm inthickness) through a GaAsP buffer layer (2 μm in thickness)under the influence of the intrinsic electric field of the pnjunction which had a strength of 20 V/ 300 μm (670 V/ cm).
Because of the sample thickness, most of the injectedmuons are stopped in the n-Si substrate , whose doping rateis estimated to be 1014 cm-3 on the basis of resistance data.
There have been several experimental studies for thecharacterization of the muon states at low temperatures inthis type of Si sample and the following observations
weremade [6]: 30% was Mu state located at
BC-site(BC-Mu), 10% was in diamagnetic state and themissing fraction of muon polarization was 0.70.
From the “Off-On” effect observed in the LF
decoupling data, we can conclude that the state in which
response to laser is observed is BC-Mu because in the statein which response to the laser is observed, the Mu aredecoupled by the LF by following a correct decoupling
1
Interdisciplinary Graduate School of Medicine and Engineering,
University of Yamanashi
2
Physics Department, University of California, Riverside3
Muon Science Laboratory, IMSS, KEK
4ISIS, Rutherford Appleton Laboratory
5
Graduate School of Arts and Sciences, University of Tokyo
6
Graduate School of Engineering, Nagoya University
7
Daido Institute of Technology

Fig. 1 The schematic
structure(GaAs/GaAsP/Si) andband gaps of the sample
used in the present
experiment and in the
KEK experiment[1].

procedure using a known hfs constant [6]. At the same time,
the laser “On” effect can be considered to process thecharacteristic of time-delayed nucleation. Thus, theinteraction between the lasers and BC-Mu can beconsidered to be due to the CE induced by lasers andtransported through the Si substrate by the intrinsic pnjunction voltage mentioned above.
In order to observe the diffusion length of the CE,
measurements were carried out to determine thedependence of the “Off-On” effect on the position at which
the muon stops. By changing the thickness of the range
absorber, the muon energy can be adjusted and the position
at which the muon stops in 200-μm thick n-Si substrate canbe changed.
In the present measurement, the expected dependence
on the position at which the muon stops was clearlyobserved. Within the currecnt spatial resolution, the averagetime-delay of 300-ns was observed by changing stopping
position by 100-μm; this indicates average CE velocity of
10-6c (c: light velocity).
In order to understand the nature of the CE produced
at p-GaAs and transported into the n-Si substrate throughthe interfaces, the dependences on the laser timing withreference to the muon pulse was measured. It was foundthat the “Off-On” effect exists even for a negative timing of
3 μs; the electron produced by lasers 3 μs before muon
arrival does exist and interact with BC-Mu.
A trial was conducted to detect CESP, as in the
n-GaAs experiment. By using 100% circularly polarizedlasers with an energy of 1.5 mJ and a wavelength of 815 nm,
a limited polarization effect was observed. The effect interms of “Para-Anti”, which refers spins of Mu and CE
parallel and anti-parallel, was 0.12(0.11)% out of-4.13(0.05)% “Off-On” effect.
In conclusion, the CEs in Si were optically produced in
p-GaAs overlayer and electrically injected by intrinsic p-n
voltage; CEs showed the following novel behaviors : a) thetransport velocity is of the order of 10-6c, and b) a large
fraction of CEs have a long life time of the order of μs.
[1] E. Torikai et al.: Physica B 289-290,558 (2000).
[2] K. Yokoyama et al.:Physica B 404, 856 (2009).
[3] K. Yokoyama et al.:RIKEN-APR 42, 234 (2008).
[4] I. Appelbaum et al.:Nature, 447, 295 (2007).
[5] B. Huang et al.: Phys. Rev. Lett., 99, 177209 (2007).
[6] K.H. Chow et al.: Phys. Rev. B 50, 8918 (1994).

- 240 -

S(t) [%]RIKEN Accel. Prog. Rep. 43 (2010)- 241 -

0.5
0.4
0.3
0.2
0.1
0.0
-0.1
-0.2
-0.3
-0.4
-0.5

x AMu = 0.46 %-1= (0.286 0.039) s

*

0

1

2

3

Time [ s]456RIKEN Accel. Prog. Rep. 43 (2010)

Study of the pressure-induced charge-transfer phase transition in(C5H11)4N[FeIIFeIII(C2O2S2)3] by μSR spectroscopy
M. Enomoto,＊1 N. Kida,＊1 I. Watanabe,＊2 T. Suzuki,＊2 Y. Ishii,＊2 and N. Kojima＊1＊1＊2

Graduate School of Arts and Sciences, The University of Tokyo
Advanced Meson Science Laboratory, RIKEN

20.4
Asymmetry / %We have previously investigated the magnetic properties
ofmixed-valenceironcomplexes,(n-CnH2n+1)4N[FeIIFeIII(dto)3] (dto = C2O2S2, n = 3, 5), in
which both ferromagnetic transition and a novel
charge-transfer phase transition (CTPT) take place.1) During
the CTPT, an electron transfer coupled with spin transition
between FeII and FeIII occurs to minimize the free energy inthe whole system. The spin states of the [FeIIFeIII(dto)3]
layer strongly depend on the size of an intercalated cation.
On the basis of the magnetic-susceptibility and 57Fe
Mössbauer spectroscopy, it was determined that the CTPT
takes place around 120 K in the complex with n = 3, while
it does not take place between 2 and 300 K in the one with n= 5. The low-temperature phase (LTP) with FeII (S = 0) and
FeIII (S = 5/2) causes ferromagnetic transitions at TC = 7 K
in the complex with n = 3, while the high-temperature phase(HTP) with FeII (S = 2) and FeIII (S = 1/2) gives rise toferromagnetic transition at 19.5 K in the complex with n = 5.
2)
In the case of the complex with n = 5, the CTPT withwide thermal hysteresis is observed in the temperaturedependence of the magnetic susceptibility at pressures
above 0.5 GPa.3) Moreover, the Curie temperature shifts
from 19.5 K to 7 K at 0.5 GPa, which implies that the LTP
responsible for the low Curie temperature of 7 K appears
above 0.5 GPa in the complex with n = 5. Recently, we
have measured the muon spin relaxation (μSR) for the
CTPT of the complex with n = 3. An anomalous increase inthedynamic
temperature-dependentmuon-spin
depolarization rate with a thermal hysteresis loop is
observed between 60 and 140 K; over this temperature
range, a corresponding anomalous decrease in the magnetic
susceptibility with a thermal hysteresis loop is observed forthe complex with n = 3. This anomaly is not observed in thecase of the complex with n = 5. The origin of this anomaly
has been successfully determined to be the dynamic processof electron transfer between FeII and FeIII, and its frequency
has been estimated from LF-μSR measurements to be about
0.1 MHz . This result is the first observation of a dynamic
electron-transfer process in such mixed-valence complexes
by μSR measurement.4) On the basis of these observationsfor (n-CnH2n+1)4N[FeIIFeIII(dto)3], the dynamic process of
the CTPT for the complex with n = 5 under high pressure
can be studied using μSR measurements. Since totalmagnetization was observed in the magnetic-susceptibility
measurement, it is difficult to distinguish the spin states ofeach iron site. Till date no microscopic magnetic
investigation has been performed under high pressure for

20.2
20.0
19.8
19.6

○: applying pressure◆: reducing pressure

19.4
0.2 0.3
0.4
0.5
0.6
0.7 P / GPa
Fig. 1 Pressure dependence of the asymmetry change
the complex with n = 5 to study the changes in the magnetic
state. Such investigation is particularly important forunderstanding the dynamic properties of the CTPT. The
μSR technique is suitable for distinguishing the static anddynamic magnetic states.
In order to investigate the pressure-induced CTPT for thecomplex with n = 5, we have carried out μSR measurement
for the complex with n = 5 at 150 K under high pressures
ranging from 0.3 to 0.64 GPa using 4He-gas-operatedpressure device at the RIKEN-RAL Muon Facility of theRutherford Appleton Laboratory. The gas-operated system
has the advantage of that the correct pressure is applied tothe sample over the whole measurement temperature range.
As shown in Fig. 1, the asymmetry for the sample with n =5, which includes the signal from Cu-Be pressure cell,remains almost constant up to 0.55 GPa, while it rapidly
decreases with increasing pressure above 0.6 GPa. In thisexperiment, pressure hysteresis has been ignored. Further,
applying pressure induces CTPT, which causes spin
fluctuation. This spin fluctuation leads to a decrease in theasymmetry. The pressure dependence of the asymmetry
changeisconsistentwiththeresultofmagnetic-susceptibility measurement under high pressure ina liquid medium.
References

1) N. Kojima, W. Aoki, M. Itoi, Y. Ono, M. Seto, Y. Kobayashi,
and Yu. Maeda: Solid State Commun. 120, 165 (2001).
2) M. Itoi, Y. Ono, N. Kojima, K. Kato, K. Osaka, and M. Takata:Eur. J. Inorg. Chem., 1198 (2006).
3) Y. Kobayashi, M. Itoi, N. Kojima, and K. Asai: J. Magn. Magn.
Matter., 272-276, 1091 (2004).
4) (a) N. Kida, M. Enomoto, I. Watanabe, T. Suzuki, and N.
Kojima: Phys. Rev. B 77, 144427 (2008). (b) M. Enomoto, N.
Kida, I. Watanabe, T. Suzuki, and N. Kojima: Physica B 404,
642 (2009).

- 242 -

RIKEN Accel. Prog. Rep. 43 (2010)

Investigating the role of protons in the unusual muon-spin relaxationof single molecule magnets†
T. Lancaster,∗1 S.J. Blundell,∗1 F.L. Pratt,∗2 I. Franke,∗1 A.J. Steele,∗1 P.J. Baker,∗2 Z. Salman,∗3 C. Baines,∗3
I. Watanabe,∗4 S. Carretta,∗5 G.A. Timco,∗6 and R.E.P. Winpenny,∗6[Molecular magnet, muon-spin relaxation]

A(t) (%)

Molecular nanomagnets (MNMs)1) comprise clusters
of exchange-coupled transition metal ions which often
have a negative anisotropy constant favoring a groundstate with a large eigenvalue of the electronic spin component Sz . MNMs have been successfully probed using
techniques such as magnetization, heat capacity, neutron scattering and electron spin resonance. In contrast, measurements made using muon spin relaxation(µ+ SR) have proven difficult to interpret. In orderto address the question of what the muon probes in
MNM systems we have made identical µ+ SR measurements on protonated and deuterated samples of Cr7 Mn(S = 1) and Cr8 (S = 0) (structure shown in Fig. 1).
To compare the Cr7 Mn and Cr8 systems, measurements were made over the temperature range 2 ≤ T ≤100 K. In this regime the spectra for S = 1 Cr7 Mn(Fig. 1(a)) were found to be describedby the relax√
ation function A(t) = A1 exp(− λt) + Abg , where Abg

20
18
16
14
12
10
8
6
4
2
0
0.0

(a)

(b)

Cr7Mn-h
Cr7Mn-d
0.5

Cr8-h
Cr8-d

1.0

1.5

t ( s)

2.0

0.0

0.5

1.0

1.5

t ( s)

2.0

2.5

Fig. 1. µ+ SR spectra for protonated and deuterated (a)Cr7 Mn and (b) Cr8 materials, measured at T = 4.5 K.
Inset: structures of the molecules.
†

∗1
∗2
∗3
∗4
∗5
∗6

Condensed from Phys. Rev. B 81, 140409(R) (2010)
Clarendon Laboratory, Oxford University Department of
Physics, Parks Road, Oxford, OX1 3PU, UK
ISIS Facility, Rutherford Appleton Laboratory, Chilton, Oxfordshire OX11 0QX, UK
Laboratory for Muon-Spin Spectroscopy, Paul Scherrer Institut, Villigen, CH
Muon Science Laboratory, RIKEN, 2-1 Hirosawa, Wako,
Saitama 351-0198, Japan
Dipartmento di Fisica, Università di Parma, I-43100 Parma,
Italy
Department of Chemistry, University of Manchester, Oxford
Road, Manchester, M13 9PL, UK

accounts for any background contribution from muonsthat stop in the sample holder or cryostat tails. Thisbehavior is typical of that observed previously in MNM
materials and arises because of the complex dynamic
distribution of local fields within the material sampled
by the muon ensemble.
The spectra measured for the S = 0 Cr8 samples
are quite different (Fig 1(b)). In this case the relaxation rate is far smaller and resembles a KuboToyabe (KT) function fKT (∆t) with ∆ = γµ B 2 
where γ = 2π × 135.5 MHz T−1 is the muon gyromagnetic ratio and B is the local magnetic field at amuon site Our conclusion from these measurements isthat the muon is sensitive to the disordered nuclear
moments in Cr8 . This is confirmed by the applicationof a small longitudinal magnetic field which quenches
the relaxation. Most importantly, the dramatic difference between the measured spectra and relaxation
rates for S = 0 Cr8 and S = 1 Cr7 Mn samples (Fig. 1)strongly suggests that the muon response in MNM systems with S = 0 stems from dynamic fluctuations of
the electronic spin. In the absence of an electron spinin Cr8 , the muon spin is relaxed by quasistatic disordered nuclear moments.
The temperature dependence of the relaxation rate
λ for the protonated (λh ) and deuterated (λd ) Cr7 Mn
samples was measured. On cooling below T ∼ 50 K,
the relaxation rate λ increases before saturating below∼ 10 K. with the onset of the increase and the saturation occurring at similar values of T for both materials.
This T -dependence is common to nearly all MNM systems that have been previously measured with µ+ SR.
At high T we see that λd > λh . It is likely that atthese high temperatures the electronic spins are fluctuating very fast and are at least partially motionally
narrowed from the spectra. Upon cooling the increasein λ is greater for the deuterated sample, with λd becoming greater than λh below ≈ 15 K. Most significantly the saturation of the relaxation at T < 10 K
occurs with λd > λh . The T -dependence of the ratio
λd /λh increases on cooling.
A full account of this work may be found in Ref.1) .
References
1) T. Lancaster et al., Phys. Rev. B 81, 140409(R) (2010).

- 243 -

RIKEN Accel. Prog. Rep. 43 (2010)

Muon-spin rotation and relaxation on the one-dimensional coordination
polymer magnet [Co(hfac)2•HNN] (HNN = hydro nitronyl nitroxide)
Takayuki Ishida,1 Yoshitomo Okamura,1 Yasuyuki Ishii, and Isao Watanabe
The first single-chain magnet [Co(hfac)2•AnNN] wasdiscovered by Gatteschi et al.1) (see below for the molecular
structure, with R = p-CH3O-C6H4). The single-chain magnet
nature is identified with magnetic hysteresis from a singlechain origin without any interchain interaction. On the other
hand, we reported the highest coercivity (HC = 52 kOe at 6K) for [Co(hfac)2•BPNN] (R = p-n-C4H9O-C6H4)2) andclarified its long-range ordered state below 40 K in the µSR
study.3) The smallest radical species (HNN; R = H) is alsoavailable for paramagnetic bridges, and α-[Co(hfac)2•HNN](CoHNN) was earlier characterized as a single-chain
magnet.4) We reexamined whether CoHNN behaves as abulk magnet.

The µSR measurements on CoHNN were carried out at
the RIKEN-RAL Muon Facility in the UK. We investigateddetailed zero-field muon-spin relaxation over a wide
temperature range (Fig. 1a). We obtained a superposition ofslow- and fast-relaxation curves. The time spectra wereanalyzed using a double exponential equation withmodification of the Kubo-Toyabe function. The relaxation
rate constant (λslow) and the total initial asymmetry A(0) areplotted as a function of temperature (Fig. 1b). A sharp peakof λ was observed at 27 K, and a plateau of A(0) was
observed below 27 K. Extremely slow depolarization and aconstant A(0) are indicative of completely frozen systems
such as magnetically ordered systems. The temperature atwhich λ diverges is usually defined as a magnetic phasetransition temperature.
Below 22 K, wiggling spectra were recorded (Fig. 2a).
The oscillation due to the muon Larmor precession clearly
indicates the presence of an appreciable internal magnetic
field attributed to spontaneous magnetization. The
coherency of the rotation implies the presence of amagnetically ordered state. The small amplitude of theoscillation may be related to the size of the magnetic
domain. The frequency and amplitude are almost constant
up to 22 K; in other words, on warming, the long-rangeordered state disappears suddenly around 22 K without any
decrease of the internal field (ca. 200 G; Fig. 2b).
Taking into account the present µSR results together withthe results of our previous experiments, 4) the magneticallyordered state of CoHNN can be interpreted as follows. On
cooling from 27 K, which can be defined as an intrinsic TN,

CoHNN enters into the quasistatic magnetically orderedstate. The appearance of the quasistatic long-range orderedstate below 22 K is sensed by muons. The dynamics
observed from ac susceptibility measurements below TN canbe attributed to the freezing of domain-wall motion, as in
the case of [Co(hfac)2•BPNN].3)
In conclusion, the one-dimensional magnet CoHNN
undergoes a magnetic phase transition at 27 K, and thedomain-wall motion freezes below 22 K at the timescale of
µSR.
(a)

(b)

Fig. 1. (a) ZF-muon spin relaxation observed for CoHNN.
(b) Temperature dependence of the depolarization rate
constant (λslow) and corrected initial asymmetry (A(0)).
(a)

(b)

Fig. 2. (a) ZF-muon spin rotation observed for CoHNN.
Solid lines represent best-fit curves. (b) Internal field (fromthe oscillation frequency) as a function of temperature.
References
1) A. Caneschi, D. Gatteschi, N. Lalioti, C. Sangregorio, R.
Sessoli, G. Venturi, A. Vindigni, A. Rettori, M. G. Pini, and M.
A. Novak: Angew. Chem. Int. Ed. Engl. 40, 1760 (2001).
2) N. Ishii, Y. Okamura, S. Chiba, T. Nogami, and T. Ishida: J.
Am. Chem. Soc. 130, 24 (2008).
3) T. Ishida, Y. Okamura, and I. Watanabe: Inorg. Chem. 48, 7012
(2009).
4) N. Ishii, T. Ishida, and T. Nogami: Inorg. Chem. 45, 3837
(2006).

1

Department of Engineering Science, The University of ElectroCommunications- 244 -

RIKEN Accel. Prog. Rep. 43 (2010)

Zero-Field and Longitudinal-Field µSR Studies of
Quasi-One-Dimensional Organic Conductor, TMTTF2 PF6
Y. Ishii, M. Nagasawa∗1 , I. Watanabe, T. Suzuki, T. Matsuzaki H. M. Yamamoto, and R. Kato
After the discovery of the ﬁrst organic pressureinduced superconductor, (TMTSF)2 PF6 (TMTSF =tetramethyltetrathiofulvalene) at 12 kbar in 19801) ,a family of quasi-one-dimensional (Q1D) organic conductors, (TMTSF)2 X and (TMTTF)2 X (TMTTF =tetramethyltetraselenafulvalene, X = monovalent anion), has been investigated extensively. A wide varietyof ground states such as the spin-Peierls (sP) state, antiferromagnatic (AF) state, spin-density wave (SDW)
state and superconducting (SC) state appear depending on the pressure or choice of anion X. The spinPeierls transition is one of the unique phenomena in
Q1D antiferromagnetic spin chain systems. However,there are only a few materials that undergo the sP
state. This is because antiferromagnetic chains often
enter a three-dimensional magnetic ordered state, suchas AF and SDW state, because of interchain coupling.
In this study, we aim to investigate the magnetic properties of the sP state of the PF6 salt.
Single crystals used in this study were synthesized
by the standard electrochemical method. ZF- and LFµSR experiments were carried out using the ARGUS
spectrometer installed at port 2 of the RIKEN-RAL
Muon Facility in the U. K.2,3) . The facility provides aintense pulsed muon beam. Randomly oriented crystals with a total weight of 120 mg were wrapped ina silver foil, and the wrapped sample was formed toa disk-like shape. The sample was cooled to 0.26 K
using a 3 He cryostat.
Figure 1 shows the ZF-µSR time spectra at temperature above and below TsP . Above TsP , the ZF-µSR
time spectra are almost unchanged and the spectra
show exponential-like relaxation. Below TsP , the relaxation rate is signiﬁcantly enhanced and the µSRtime spectra do not show simple exponential relaxation as the temperature decreases. Moreover, below
1 K, a strange change in the µSR time spectrum is observed when a ﬁeld is applied. Figure 2 shows the lowtemperature muon time spectra obtained for µ0 HLF =0.1 mT. The spectrum correspond to 0.26 K can be ﬁtted to the function A(t) = AS exp(−(λt))×cos(ωt+θ).
The internal ﬁeld at the muon site, Bint , can be calculated as Bint � 10 G by using the relation Bint = γµ /ω,where γµ = 2π×13.5534 kHz/G is a gyromagnetic ratioof the muon spin. Interestingly, under zero-ﬁeld conditions, no signiﬁcant change was observed in the µSRtime spectra between 1.5 K and 0.26 K. This suggeststhat some kind of unconventional magnetic ordering
may appear at lowt emperatures. Further investigations are necessary to clarify this unconventional be∗1

Department of Physics, Tokyo Denki University

Fig. 1. ZF-µSR time spectra of TMTTF2 PF6 at temperature above and below TsP = 18 K.

Fig. 2. Low-temperature µSR time spectra of TMTTF2 PF6
at µ0 HLF = 0.1 mT.

havior.
References
1) D. Jérome, A. Mazaud, M. Ribault and K. Bechgaard,
J. Phys. Lett. France 41(1980) L95.
2) T. Matsuzaki, K. Nagamine, M. Tanase, M. Kato, K.
Kurosawa, H. Sugai, K. Ishida, S. N. Nakamura, I.
Watanabe and G. H. Eaton, Nucl. Instr and Meth. A
480 (2002) 814.
3) K. Nagamine, T. Matsuzaki, K. Ishida, I. Watanabe, R.
Kadono, G. H. Eaton, H. J. Jones, G. Thomas and W.
G. Williams, Hyperﬁne Interact. 87 (1994) 1091.
4) S J Blundell, F L Pratt, P A Pattenden, M Kurmoo, K
H Chow, S Takagi, Th Jestädt and W Hayes, J. Phys.:
Condens. Matter f9 (1997) L119.

- 245 -

RIKEN Accel. Prog. Rep. 43 (2010)

High-Pressure µSR Study of an Organic Spin-Peierls Material
MEM-[TCNQ]2

Raw Asymmetry %

10

0
0

Raw Asymmetry / %MEM-[TCNQ]2
0.1 MPa20

4
6Time / μs

8

10

10

0
0

2

4
6
Time / μs

40 K
2.5 K

8

4
6
Time / μs

810MEM-[TCNQ]2590 MPa

20

10

0
0

2

4
6
Time / μs

40 K
2.5 K

8

10

Fig. 2. µSR time spectra of MEM-[TCNQ]2 for 300 and
590 MPa.

µSR time spectra obtained below 100 MPa areshown in ﬁg. 1. At 2.5 K, an exponential-like fastdamping component of small magnitude is observed
at both 0 and 100 MPa. This component should
be a characteristic feature of the spin-Peierls groundstate5) . However, it is diﬃcult to ﬁnd out this exponential component analytically, because in the obtained µSR time spectra, a paramagnetic component
from the pressure cell is dominant. Detailed analyses
are underway. On the other hand, there are no signsof a spin-gap or of magnetic ordering above 300 MPa
even at the base temperature. This suggests that the
ground state above 300 MPa is a paramagnetic one.
This result is quantitatively inconsistent with previous
high-pressure magnetic measurements6,7) .

10

Fig. 1. µSR time spectra of MEM-[TCNQ]2 for 0 and 100
MPa.
∗1

2

40 K
2.5 K

1) S. Huizinga et al.: Phys. Rev. B 19, 4723 (1979).
2) T. Matsuzaki et al.: Nucl. Instr and Meth. A 480, 814(2002).
3) K. Nagamine et al.: Hyperﬁne Interact. 87, 1091 (1994).
4) I. Watanabe et al.: Physica B In Press.
5) S J Blundell et al.: J. Phys.: Condens. Matter 9, L119
(1997).
6) D. Bloch et al.: Physica 119 B, 43 (1983)
7) S. Takagi et al.: Mol. Cryst. Liq. Cryst. 376, 377 (2002).

MEM-[TCNQ]2
100 MPa

20

10

References

40 K
2.5 K
2

MEM-[TCNQ]2
300 MPa

20

0
0

Raw Asymmetry / %Long-range magnetic order cannot be induced in
ideal one-dimensional spin system. The spin-Peierls(sP) transition, which is a unique phenomenon in quasi
one-dimensional antiferromagnetic spin chain systems,
gives rise to a gap in the magnetic excitation spectrum.
The driving force for the sP transition is the magnetoelastic coupling between the one-dimensional spin structure and three-dimensional lattice vibrations. Very few
materials exhibit sP transition. This is because antiferromagnetic chains often become three-dimensional
magnetic ordered state because of interchain interaction.
MEM-[TCNQ]2 (N-Methyl-N-ethyl-morphorinium[7,7’,8,8’-tetracyanoquinodimethane]2 ) forms one dimensional stacking structure of TCNQ molecules. This
compound exhibits spin-Peierls transition at transition
temperature TsP = 18 K1) . We carried out µSR measurement of MEM-[TCNQ]2 under high-pressure since
it is expected that sP state is destabilized by applying pressure because the inter-chain coupling should
increase with pressure.
Single crystals of MEM-[TCNQ]2 were grown froman acetonitrile solution, which contained TCNQ and
MEMiodine, by a slow diﬀusion method. The productwas obtained as ﬁne black needles with a typical lengthof 1 mm. High-pressure µSR experiments were carriedout using the ARGUS spectrometer that is installedat the RIKEN-RAL Muon Facility in the UK2–4) . The
facility can provide a high-momentum muon beam thatcan pass through the window of a high-pressure cell.

Raw Asymmetry / %Y. Ishii, H. Komatsu∗1 , Y. Manabe∗1 , A. Taniguchi∗1 , H. Taniguchi∗1 , K. Satoh∗1 , I. Watanabe
and T. Matsuzaki

Department of Physics, Saitama University- 246 -

RIKEN Accel. Prog. Rep. 43 (2010)µSR study on the spin-singlet state in cluster magnet GaNb4 S8 †∗1

Department of Materials Science and Engineering, Kyoto
University

0.5

0.8

0

0

0.8

0.4

0.6

0.2
0.4
0

2

4

6
8
t (µsec)

Ts
20

1

0.6

0

λ
β

100 K
25 K
4.5 K

40

60

80

5
-1
λ (10 sec )1βA mixed-valent magnetic cluster system, in whichatoms in the cluster share unpaired electrons, is very
attractive as an intermediate system between a localized spin system and an itinerant electron magnet.
As a category of such materials, the ternary chalcogenides AB4 X8 (A = Ga, Al, Ge; B = V, Mo, Nb, Ta;
X = S, Se), having cubic GaMo4 S8 structure (spacegroup F 4̄3m), are of particular interest1–4) . In thecompounds, the cubic (B4 X4 )n+ and the tetrahedral(AX4 )n− ions are weakly coupled in the NaCl manner,
resulting in hopping conduction between the clusters.
These compounds are generally semiconducting with anarrow bandgap. In the (B4 X4 )n+ ion, one can ﬁnda tetrahedral cluster (tetramer) of magnetic B-atoms
in which d electrons form cluster orbitals. Intracluster
and intercluster interactions result in a wide variety ofmagnetic properties.
GaNb4 S8 has attracted attention as a Mott insulator in which 4d electrons are localized in Nb4 clusters
due to electron correlations and also as one of pressureinduced superconductors1) . In the compound, the Nb4
tetramers have a local moment with S = 1/2. The
magnetic susceptibility of the compound obeys theCurie-Weiss law with the eﬀective moment (µeﬀ ) of
1.73 µB /f.u. and the Weiss constant (θ) of −298K1) .
The large negative Weiss constant suggests that theantiferromagnetic (AF) coupling exists between theclusters. The compound exhibits a structural phasetransition from the high-temperature cubic state to
the tetragonal state (P 4̄21 m) at a temperature (Ts )of 32 K2) . This phase transition is possibly due to
the Jahn-Teller instability of the degenerate molecular orbital of the the Nb4 tetramers. Our zero-ﬁeld(ZF) and longitudinal-ﬁeld (LF) µSR studies5) indicate that the magnetic ground state in GaNb4 S8 is a
non-magnetic spin-singlet state. The details are provided below. From the lattice symmetry2) , it is suggested that the spin-singlet state is formed because offormation of the Nb8 octamer from two Nb4 tetramers.
The ZF and the LF µSR experiments on GaNb4 S8were conducted at the RIKEN-RAL Muon Facility at
the Rutherford-Appleton Laboratory in the UK in thetemperature (T ) range of 4.5−100 K in a LF of 0−3950
G. All experiments were performed using polycrystalline samples obtained from the solid-state reactionof pure elements sealed in evacuated quartz tubes.
Even at the lowest temperature, the ZF µSR spectra, shown in Fig. 1, exhibit no oscillation due tothe muon precession caused by the static internal ﬁeld.
This clearly indicates the absence of a magnetic long-

Asymmetry (arb. units)

Y. Tabata,∗1 Y. Kajinami,∗1 T. Waki,∗1 I. Watanabe, H. Nakamura∗1

10
0.2

0
100

T (K)

Fig. 1. T -dependence of λ and β. Above 27.5 K, the valueof β is ﬁxed at 1. Inset: Typical Examples of ZF-µSR
spectra at T = 4.5, 25, and 100 K. The solid curves
represent the ﬁt by the damped KT function describedin the text. Below Ts , the spectra are ﬁt with a phenomenological stretched exponential function.

range order at temperatures below Ts . The relaxation
curve can be ﬁtted by a phenomenological damped
Kubo-Toyabe (KT) function with a stretched exponential function given by Pµ (t) = exp[−(λt)β ]GKTz (∆, t),
2
1 2 2
1
2 2
where GKTz (∆, t) = 3 + 3 (1−∆ t ) exp(− 2 ∆ t ). The
KT relaxation rate ∆ is almost independent of temperature and the damping rate λ exhibits a gradual increase with a decrease of temperature below 40 K. The
exponent β is considered a free ﬁtting parameter at low
temperatures, and above 27.5 K, its value is ﬁxed at
1 because λ is too small to determine β precisely byﬁtting the data. Thus, the cusp-like anomaly of λ ataround 25 K may be an artifact of the curve-ﬁtting.
The stretched exponential relaxation is not decoupled
by an applying LF up to 3950 G; this clearly indicates that the increase in λ below Ts mainly due to the
dynamic internal ﬁeld resulting from ﬂuctuating electronic spins. These results can be considered as sporadic dynamics of spin ﬂuctuations in the spin-singlet
sea6) , and they also indicate that the spin-singlet stateof GaNb4 S8 is formed because of the formation of Nb8
octamers from two Nb4 tetramers.
References
1) R. Pocha R et al.: J. Am. Chem. Soc. 127, 8732 (2005).
2) S. Jakob et al.: J. Mater. Chem. 17, 3833 (2007).
3) R. Pocha R et al.: Chem. Mater. 12, 2882 (2000).
4) H. Nakamura et al.: J. Phys.: Conf. Series 145, 012077(2009).
5) T. Waki et al.: Phys. Rev. B 81, 020401(R) (2010).
6) Y. J. Uemura et al.: Phys. Rev. Lett. 73, 3306 (1994).

- 247 -

RIKEN Accel. Prog. Rep. 43 (2010)

Magnetic order of the frustrated triangular lattice antiferromagnet
HCrO2 †
H. Kikuchi,∗1 Y. Fujii,∗2 I. Watanabe,∗3 T. Suzuki,∗3 and T. Kawamata∗3[Spin frustration, antiferromagnet, magnetic order]
Geometrically frustrated magnets have attracted
much interest recently because their high degeneracy
generates new phenomena such as spin liquid state. A
triangular lattice antiferromagnet (TAF) is a typicalfrustrated magnet and has been studied extensively.
HCrO2 is a model compound of the TAF. Edge-sharing
CrO6 octahedra form a layer in the c plane, and Cr3+
ions (S = 3/2) form the triangular lattice. The Weisstemperature of HCrO2 has been estimated to be -276
K from magnetic susceptibility measurements above
77 K [1]. About two decades ago, Y. Ajiro et al. [2]measured the X-band ESR (electron spin resonance)
spectra of HCrO2 and discussed the temperature dependence of the ESR linewidth in terms of the Z2
vortex excitation, which is a topological defect predicted for the Heisenberg triangular-lattice antiferromagnet [3]. They observed that the ESR linewidth ofpolycrystalline HCrO2 diverged at around 20 K, which
agrees with the predicted temperature for the Z2 vortex phase transition. No magnetic study of HCrO2 hasbeen performed since the study in [2]. We measured
the µSR spectra of HCrO2 and DCrO2 to investigate
the magnetic properties of these frustrated magnets.
Powder samples were synthesized using a hydrothermal method.

HCrO

Asymmetry20

Zero-ﬁeld (ZF) and longitudinal-ﬁeld (LF) µSR
spectra were measured at the RIKEN-RAL Muon Facility at temperatures down to 0.1 K and for ﬁelds up
to 3950 Oe. Figure 1 shows temperature dependence of
the ZF-µSR time spectra of HCrO2 . At high temperatures the spectra can be ﬁtted with Gaussian curve.
Below about 20 K, a fast relaxing component rapidly
develops so that exponential decay becomes prominent
at lower temperatures. The observation clearly indicates that a magnetic transition occurs at around 20
K. However, since no spin rotation was observed evenat the lowest temperature of 0.1 K, it is suggested thatthe magnetic phase below 20 K is characterized not bya long-range order, but a short-range order. Figure 2
shows the LF dependence of the time spectra of HCrO2
measured at 0.1 K. Almost no change is observed whenthe magnetic ﬁeld is increased to 1000 Oe. At the highest magnetic ﬁeld of 3950 Oe, decoupling of the muon
relaxation is still insuﬃcient, suggesting that the magnetic moments are dynamic even at 0.1 K.





2

40 K
35 K
20 K
15 K
10 K
0.1 K

10



1

2

3

4

5











0
0



Fig. 2. LF dependence of the time spectra of HCrO2 at 0.1
K up to 3950 Oe.

6μs)

References
Fig. 1. Temperature dependence of the time spectra ofHCrO2 .
∗1
∗2
∗3

Department of Applied Physics, University of Fukui
Research Center for Development of Far-Infrared Region,
University of Fukui
Advanced Meson Science Laboratory, RIKEN Nishina Center

1) R. G. Meisenheimer and J. D. Swalen: Phys. Rev. 123,
831 (1961).
2) Y. Ajiro et al.: J. Phys. Soc. Jpn. 57, 2268 (1988).
3) H. Kawamura and S. Miyashita: J. Phys. Soc. Jpn. 53,
4138 (1984).

- 248 -

RIKEN Accel. Prog. Rep. 43 (2010)µSR Study of Ordered Phases in Triangular Ising-like
Antiferromagnets CsCoCl3 and CsCoBr3
T. Kawamata, Y. Nishiwaki,∗1 T. Kato,∗2 T. Nakamura,∗3 Y. Tanabe∗4 and I. Watanabe[µSR, frustration system]
Recently, cooperative phenomena with different degrees of freedom in a frustration system have attracted
interest. In particular, RbCoBr3 is a unique frustration compound with spin and lattice frustration,
as suggested by a new spin-lattice model,1) which is
introduced in the frustration of not only spin systems but also lattice systems, say “lattice frustration”.
RbCoBr3 has been classified as an ABX3 -type compound. The ABX3 -type compounds are well-known
frustrated magnets, which have chains formed by facesharing BX6 octahedra. This model shows that the
spins of the Co2+ ions and those of the lattice chainschange their alignments cooperatively to minimize theenergy for releasing the frustrations.
RbCoBr3 undergoes several magnetic and structuralphase transitions. It has been suggested by neutron
scattering measurements2) that a partial disordered(PD) phase appears below TN1 = 37 K and thata three-sublattice ferromagnetic (3FR) phase appears
below TN2 = 32 K, with a decreasing in temperature.
However, our previous µSR result3) suggested that the3FR phase appears at temperatures between TN1 andTN2 . The two frequency components, ∼ 4 MHz and ∼ 8
MHz, observed between TN1 and TN2 during µSR measurements are consistent with those determined by our
dipole field calculations on the 3FR phase, while thecalculations on the PD phase indicate the existence of
only one frequency component. Furthermore, the spinlattice model predicts that the 3FR phase in RbCoBr3
appears in a very small temperature regime at aroundTN1 .1) Therefore, there is a possibility of the 3FR phaseappearing between TN1 and TN2 . In order to determine
the exact number of frequency components in the PD
phase, we carried out µSR experiments on CsCoCl3
and CsCoBr3 , in which the PD phase is known to beestablished at low temperatures.
CsCoCl3 and CsCoBr3 are ABX3 -type compounds,
and hence, in these compounds, magnetic phase transitions occur at TN1 = 21 K, TN2 = 9 K and TN1 =28 K, TN2 = 13 K, respectively. The PD phase of
CsCoCl3 and CsCoBr3 is observed between TN1 andTN2 . µSR measurements have been carried out in thepast on CsCoCl3 using pulsed muon beam at KEK
and dc beam at TRIUMF. The results suggested theexistence of only one component of the muon-spin ro∗1

∗2
∗3
∗4

Dept. of Physics, Tokyo Women’s Medical University
Faculty of Education, Chiba University
Faculty of Engineering, Shibaura Institute of Technology
Dept. of Applied Physics, Tohoku University

Fig. 1. Temperature dependence of precession frequency
obtained by Fourier analysis of (a) CsCoCl3 and (b)CsCoBr3 .

tation at ∼ 4 MHz.4) We must carry out experiments
on CsCoCl3 again because there is a possibility of thehigh-frequency component remaining undetected owing to the low statistics of the data obtained in the previous experiments. The present µSR measurements on
CsCoCl3 and CsCoBr3 are performed at the RIKENRAL Muon Facility.
Clear muon spin rotation is observed below TN1 ∼21 K and ∼ 28 K in the µSR spectra of CsCoCl3
and CsCoBr3 , respectively. Figure 1 shows the temperature dependence of the precession frequency of
CsCoCl3 and CsCoBr3 obtained by Fourier analysisof the spectra. Only one broad component is observedin the PD phase between TN1 and TN2 in both compounds. This result suggests that there is only one
broad component in the PD phase in an ABX3 system.
Accordingly, it is likely that the magnetically orderedstate between TN1 and TN2 in RbCoBr3 is the 3FR
phase, which contradicts with the results suggested by
the neutron scattering experiment2) .
References
1) T. Nakamura and Y. Nishiwaki: Phys. Rev. B 78,
104422 (2008).
2) Y. Nishiwaki et al.: J. Phys. Soc. Jpn. 77, 104703(2008).
3) T. Kawamata et al.: RIKEN Accel. Prog. Rep 42, 243(2009).
4) M. Mekata et al.: J. Magn. Magn. Mater. 104–107, 825(1992).

- 249 -

RIKEN Accel. Prog. Rep. 43 (2010)µSR Studies of the 2D Triangular-lattice Spin-liquid System
κ-ET2 Cu2 (CN)3
F.L. Pratt∗1 , S. Kawamura∗2 , T. Lancaster∗3 , S.J. Blundell∗3 , P.J. Baker∗1 , Y. Shimizu∗4 , K. Kanoda∗5 andI. Watanabe∗6[Spin liquid, magnetism]
The S=1/2 triangular-lattice antiferromagnet (AF)with nearest neighbour Heisenberg interactions was
one of the first candidates to be considered for a spinliquid (SL) ground state in the resonating-valencebond (RVB) picture1) . Although subsequent studies
indicated that non-collinear three-sublattice AF ordering is the ground state (Fig.1a), the SL state may berecovered when higher order interactions are taken into
account (Fig.1b)2,3) . These interactions are significant
in strongly-correlated electronic systems just on theinsulating side of a Mott transition4,5) , such as theorganic system κ-ET2 Cu2 (CN)3 studied here6) , whichshows SL properties down to at least 20 mK7) .

In the RVB SL phase, the spinon excitations are expected to be mobile and implanted muons may be used
to study their dynamical properties. An example of the
field dependent muon spin relaxation resulting from
unpaired electronic spins in κ-ET2 Cu2 (CN)3 is shownin Fig.2. The field dependence can be represented by
the sum of two contributions, the first term dominates
at low fields and has the form of a Lorentzian that reflects localised spin fluctuations with a single dominantrelaxation time. The second term has the characteristic logarithmic dependence of a 2D diffusion process
and is assigned to relaxation of the muon by the mobile
spinons present in the SL phase.
80 K

0.06

Localised

LF (

-1

s )

0.08

0.04

0.02

2D diffusive

0.0
0.01

0.1

1

10

100

0H (mT)

Fig. 2. Electronic contribution to the longitudinal muon
spin relaxation in κ-ET2 Cu2 (CN)3 measured at 80 K.
The field dependence can be represented by the sum(solid line) of contributions from localised and diffusing
spin excitations, with the mobile excitations dominating the relaxation for fields above 2 mT.
Fig. 1. (a) The three-sublattice ground state of S=1/2
spins on a triangular lattice with simple nearestneighbour Heisenberg interactions. (b) Higher order interactions can stabilise the RVB SL phase and one of themany degenerate configurations is shown here. Thicklines represent valence bonds and two mobile spinon
excitations are also shown.
∗1

∗2
∗3
∗4
∗5
∗6

ISIS Facility, Rutherford Appleton Laboratory, UK
JPARC, Tokai
Department of Physics, University of Oxford, UK
Department of Physics, University of Nagoya
Department of Physics, University of Tokyo
RIKEN

References
1) P. W. Anderson, Mat. Res. Bull. 8, 153 (1973).
2) G. Misguich et al, Phys. Rev. B 60, 1064 (1999);
W. LiMing et al, Phys. Rev. B 62, 2372 (2000).
3) O.I. Motrunich, Phys. Rev. B 72, 045105 (2005).
4) H. Morita, S. Watanabe and M. Imada, J. Phys. Soc.
Jpn. 71, 2109 (2002).
5) B.J. Powell and R.H. McKenzie, J. Phys.: Condens.
Matter 18, R827 (2006).
6) Y. Shimizu et al, Phys. Rev. Lett. 91, 107001 (2003);
Phys. Rev. B 73, 140407 (2006).
7) S. Ohira et al, J. Low. Temp. Phys. 142, 153 (2006).

- 250 -

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

µSR study around a quantum critical point in heavy-fermion
compounds Ce2 RhIn8−x Snx †K. Ohishi, T. Suzuki, R. H. Heﬀner,∗1,∗2 T. U. Ito,∗1 W. Higemoto,∗1 and E. D. Bauer∗2

†
∗1
∗2

Condensed from an article submitted to J. Phys.: Conf. Series
ASRC, Japan Atomic Energy Agency
Los Alamos National Laboratory, USA

25

3

20
0.5K
0.4K

0.3K
15

(a) Ce2RhIn8
10

ZF-µSR
0

8Time [µs]Ce2RhIn8-xSnx

2

SH
µSR

1
0
0.0

0.5
1.0
Sn concentration x

0.3K(b) Ce2RhIn7.5Sn0.5
3.7K

4TN [K]

2K
1.2K

Asymmetry [%]One of the most exciting topics in modern condensed matter physics is the interplay between diﬀerent electronic ground states near a quantum criticalpoint (QCP)1) . In f -electron compounds, a quantum
critical phase transition appears due to the competition between magnetic ordering (via RKKY interactions) and paramagnetic phase (via Kondo singlet
formation). It is observed that unconventional superconductivity and/or non-Fermi-liquid behavior isoften exhibited in the vicinity of a QCP, where theCurie or Neel temperature of a magnetically orderedstate approaches 0 K. Recently, it has been found thatCe2 RhIn8 has two diﬀerent QCPs; this was observed
when pressure was applied2) and when chemical substitution of Sn for In was carried out3) . In order to study
the diﬀerence between the magnetic properties of thetwo QCPs, we ﬁrst performed µSR measurements of
the Ce2 RhIn8−x Snx before performing the measurements of the Ce2 RhIn8 under pressure. The µSR
measurements were carried out at the RIKEN-RAL
Muon Facility in the U.K. Single crystalline samplesof Ce2 RhIn8−x Snx (x = 0.0, 0.1, 0.5, 0.7) were mounted
on a high-purity silver plate such that their c-axes wereparallel to the initial muon spin polarization.
Figure 1(a) shows the ZF-µSR time spectra of
Ce2 RhIn8 . At temperatures above TN , the time spectra consist of two components; the ﬁrst component
shows the slow relaxation due to random local ﬁelds
from nuclear magnetic moments, and the other component shows that the relaxation is indipendent of time.
More speciﬁcally, we have A(t) = APz (t) + AAg , where
A and AAg are the initial µ-e decay asymmetries ofthe sample and the silver backing plate, respectively.
Pz (t) = exp(−∆2 t2 ), where ∆/γµ is the rms valueof the random local ﬁeld. [Here, γµ (= 2π × 135.54
MHz/T) is the muon gyromagnetic ratio.] Note thatthe second component is a constant because the relaxation rate of the silver backing plate is negligible (∼ 0).
The time spectra were reproduced well by the above
formula with ∆ = 0.214(5) µs−1 . For T < TN , wefound that the spectra can be described well by A(t) =A1 exp(−σ12 t2 ) cos(2πf t + ϕ) + A2 exp(−σ22 t2 ) + AAg ,where σ1 and σ2 are the relaxation rates, f is the muonspin precession frequency under a local ﬁeld Hloc , andϕ is the initial phase. As shown in Fig. 1(a), a clear
precession signal was observed and TN is estimated tobe 2.8 K. A ﬁtting procedure similar to that for the par-12 0

ZF-µSR
4

8

12Time [µs]Fig. 1. ZF-µSR time spectra of (a) Ce2 RhIn8 and (b)Ce2 RhIn7.5 Sn0.5 . Inset shows TN vs. Sn concentration.

ent compound was used for the Ce2 RhIn7.9 Sn0.1 data,
and TN was estimated to be 1.8 K.
Figure 1(b) shows the ZF-µSR time spectra of
Ce2 RhIn7.5 Sn0.5 . While the relaxation rate above
2 K is almost independent of temperature, there is a
gradual increase in the relaxation rate with decreasing temperature. Muon-spin precession signal was
not observed at the lowest temperature; this indicatesthat there is no magnetic ordering at this temperature. The time spectra were described by A(t) =APz (t) + AAg using the stretched exponential function Pz (t) = exp[−(λt)β ], where λ is the relaxation
rate and β is the power of the exponent. The change
from Gaussian (β = 2) to single exponential decay(β = 1) that occurs with decrease in temperature canbe seen in the ﬁgure. The rate λ is almost independent of temperature above 0.5 K, and starts to increase
rapidly with a decrease in temperature below 0.5 K.
Such fast relaxation without any detectable oscillation
is a common signature of disordered magnetism thatis either static or dynamically ﬂuctuating. Applicationof longitudinal ﬁelds showed that these magnetic signals were completely decoupled between 100–200 mT
at 0.3 K; this observation is consistent with a static distribution of local ﬁelds. This suggests a spin-glass-like
phase, which has been observed in isostructural material Ce2 IrIn8 4) . Muon-spin precession was not observed in the sample of x = 0.7 and λ was approximately constant at ∼ 0.29 µs−1 .
As a summary of our results, the magnetic phase
diagram of Ce2 RhIn8−x Snx as a function of x is shownin the inset of Fig. 1(b). Next, we intend performingµSR measurements in Ce2 RhIn8 under pressure.
References
1) P. Coleman and A. Schoﬁeld; Nature 433, 226 (2005).
2) M. Nicklas et al.: Phys. Rev. B 67, 020506(R) (2003).
3) E. D. Bauer: Unpublished results.
4) G. D. Morris et al.: Phys. Rev. B 69, 214415 (2004).

- 251 -

1

RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)RIKEN Accel.

Precise investigation and re-examination of magnetism andsuperconductivity of high-quality Fe-based superconductor,
LaFeAsO1−x Fx
H. Fukazawa,∗1,∗5 T. Saito,∗1 Y. Kohori,∗1,∗5 K. Ohishi,∗2,∗5 Y. Ishii,∗2,∗5 I. Watanabe,∗2,∗5 K. Miyazawa,∗3,∗4
N. Takeshita,∗3,∗5 P. M. Shirage,∗3 K. Kihou,∗3,∗5 C.-H. Lee,∗3,∗5 H. Kito,∗3,∗5 A. Iyo,∗3,∗5 and H. Eisaki∗3,∗5[Iron-based superconductors, µSR, magnetic fluctuation, multiple-gap superconductivity]

∗1

∗2
∗3
∗4
∗5

Department of Physics, Chiba University
Advanced Meson Science Laboratory, RIKEN Nishina Center
National Institute of Advanced Industrial Science and Technology
Department of Applied Electronics, Tokyo University of Science
JST, TRIP

tors revealed that the superconductivity in this series of compounds basically possesses multiple superconducting gap nature. Indeed, we clarified that
two superconducting gap of distinct sizes realizes in
KFe2 As2 (Tc = 3.5 K).7) In our previous NQR (nuclear quadrupole resonance) and specific heat measurements, we utilized 3 He refrigerator: we could perform
experiments only down to about 0.3 K. Therefore, weare planning to perform zero-field (ZF) µSR measurements on KFe2 As2 down to about 50 mK in next R383
proposed experiments. Temperature dependence ofrelaxation rate derived from muon time spectra may
clarify the superconducting gap symmetry and sizes ofgaps in detail.
References
1) K. Kamihara et al., J. Am. Chem. Soc. 130, 3296
(2008).
2) Y. Nakai et al., Phys. Rev. B 79, 212506 (2009).
3) H. Ikeda, J. Phys. Soc. Jpn. 77, 123707 (2008).
4) M. Rotter et al., Angew. Chem. Int. Ed. 47, 7949
(2008).
5) H. Fukazawa et al., J. Phys. Soc. Jpn. 78, 033704 (2009).
6) H. Fukazawa et al., J. Phys. Soc. Jpn. 77, 105004 (2008).
7) H. Fukazawa et al., J. Phys. Soc. Jpn. 78, 083712 (2009).

Asymmetry [%]Much attention has been paid after the discovery ofsuperconductivity in F-doped LaFeAsO with a superconducting transition temperature Tc = 26 K.1) In overelectron-doped iron-pnictide superconductors, pseudogap like behavior was observed in normal state.2) Contrary to high-Tc cuprate, theoretical explanation forthis phenomenon is not entirely of the magnetic origin
but of specific band structure origin.3) From the viewpoint of ZF µSR, we examined the existence of magnetic fluctuation in over electron-doped iron-pnictide
superconductors.
In Fig. 1, we show the muon time spectra of
LaFeAsO1−x Fx with Tc = 19 K, which is confirmed
to locates in over-doped region from a-axis lattice parameter. The muon time spectra remain the same at
all the measurement temperatures. This result clearly
revealed that the origin of the pseudo-gap like behavior is not magnetic one. We also examined sample dependence of this temperature behavior of muon time
spectra and found that there is no sign of magnetic
fluctuation for all the measured samples (Tc = 27, 23,
and 19 K).
K-doped (hole-doped) BaFe2 As2 is the firstly reported oxygen-free iron-pnictide superconductor with
Tc = 38 K.4) We reported the 75 As nuclear magnetic
resonance (NMR) measurement of this hole-doped superconductor Ba1−x Kx Fe2 As2 with different lattice
parameters and different superconducting volume fractions (Tc ∼ 38 K).5) 75 As-NMR spectra revealed thatthe magnetically ordered and superconducting phases
are microscopically separated. In our samples synthesized by high pressure method, antiferromagnetic(AFM) ordered state remains up to x =0.4. The internal magnetic field evaluated by zero-field 75 As-NMR issuppressed by the substitution x. However, it is also
robust with x. This tendency is quite similar to thepressure dependence of the internal magnetic field in
the parent material BaFe2 As2 .6) This reflects the firstorder nature of this phase transition.
Recent experiments on iron-pnictide superconduc-

25

LaFeAs(O,F)
Tc = 19 K

20

ZF-µSR

15
98 K
53 K
30 K
21 K
11 K
5K

10
5
0

0

5

10
Time

15

20

[µs]

Fig. 1. Muon time spectra of LaFeAsO1−x Fx (Tc = 19 K).

- 252 -

1

RIKEN Accel. Prog. Rep. 43 (2010)

Effect of Pressure on the Stripe Dynamics in La2-xSrxCu1-yZnyO4 with x = 0.13
I. Watanabe, Y. Ishii, T. Kawamata, T. Suzuki, T. Adachi1), Y. Tanabe1,2), Y. Koike1), R. Khasanov3), and D. Andreica4)
The main p urpose of the experiment in th is p aper is toinvestigate the effect of pressure on the stabilization of the
stripes of spins and holes in high-Tc superconducting oxides[1]. The high-Tc sup erconductivity is stro ngly co rrelatedwith th e stab ilization and destabilization of Cu sp ins for ahole concentration of ap proximately 1/ 8 per C u at om forwhich the dynamically fluctuating stripes are consi dered to
be st abilized hence, c ontrolling t he st ripe dy namics i simportant to determine to the po int of superconductivity. It
has bee n re ported t hat t he stabilization of st ripes ca n b econtrolled by appl ying a small pressure o f 0. 2 GPa [2] .
However, rec ently, i t ha s bee n pointed out t hat t heelectronic st ate o f st ripes does not cha nge c onsiderably byeven under a pressure hi gher t han 0.2 Gpa [3] . T hus, t heeffect of pressure on stripe dynamics is still a con troversial
subject.
In order to clar ify th e ef fect of pressure on str ipe
dynamics, we chose La 2-xSrxCu1-yZnyO4 (LSCZO) with x =0.13 as th e target material for our study. In th is system, thestatic stab ilization of st ripes is clearly o bserved at low
temperature and at a specific hole concentration of around x= 0 .115 ev en w hen y = 0. The stripes are com pletely
destabilized at x = 0.13, a nd fluctuating outside t he µSR
characteristic ti me-window [4-6]. In ad dition to th is, ourgroup has clarified that the dynamics of st ripes at x = 0.13
can b e easily co ntrolled by su bstituting Cu with t henonmagnetic atom Zn [6]. It is expected that at x = 0.13, thestripes are at the borde r between stabilized and destabilizedstates. We s peculate t hat if stri pe dynamics can becontrolled b y ap plying pressu re, we will be able to detecta cha nge i n stripe dynamics by ap plying p ressure o nsamples that contain a small amount of Zn. This means thatwhen we apply p ressure to a Zn -substituted sam ple, i nwhich t he dynamic st ripes a ppear t o be st abilized, we c an
detect the disappearance of the signs of the stabilized statesof Cu spins.
We h ave alread y car ried ou t high-pressure µSR
measurements on a sample with x = 0.13 and y = 0.0025 byapplying pressure o f 0 .81 GPa. W e carried ou t themeasurements at Pa
ul Scherrer Institute (PSI)in
Switzerland an d reported the resu lt in th e APR rep ort o f
2008. From these m easurements, we di d n ot observe any
effect of pressure on the sta bilized stripes . In t he prese nt
study, we ap plied high pressure u p t o a m aximum of 1.2
GPa t o a sam ple wi th x = 0.13 and y = 0. 005; for t his
sample, t he st abilization of st ripes i s o bserved a ppears
below 10 K [6]. T he high-pressure measurem ent was
carried out at the GPD at PSI in Switzerland, as before.
＊1
*2
3)
*3

Department of Applied Physics, Tohoku University, Japan.
WPI-AIMR, Tohoku University
Bulk Muon Group, PSI, Switzerland.
Department of Physics, Babes-Bolyai University, Rumania,

Figure 1 shows the tem perature dependence of themuon-spin-precession am plitude i n TF = 2 0 G of LSC ZO
with x = 0.13 and y = 0.005. The top panel shows the dataobtained ambient pressure, and the bottom panel shows thedata m easured at 1.24 GPa. Bo th p anels show th at th emuon-spin-precession
decreases wi
th decreasingtemperature. This indicates t he appearance of the stabilizedstate of t he st ripes. Using a broadened F ermi funct ion, themagnetic transitio n tem perature was esti mated to beapproximately 6.7 K at ambient pressure and 6.0 K at 1.24
GPa. The effect pressure is quite small, and the difference inthe m agnetic t ransition tem perature is ap proximately 1 0%.
Thus, it can be stated said that statically stab ilized stri pes
cannot be dest abilized by applying a low press ure of 0.2
GPa [2].
At presen t, we areplanning t o determin th esuperconducting states under pressure for the same samples
that were used PSI. By com paring the e ffect of pressure
on stripe dynamics of samples in superconducting state, we
expect to u nderstand the rel ationship bet ween the pres sureand stripe dynamics.

Figure 1: Temperature dep endence of the amplitude of themuon-spin precession in TF 50 G for the sample with x = 0.13 andy = 0.005 . The top panel shows the r esult of µSR m easurement
and th e bottom panel shows the result of µSR m resurement at ahigh-pressure of 1.2 GPa.

References[1]J.M. Tranquada et al., Nature (London) 375, 561 (1995). •[2]S. Arumugam et al., Phys. Rev. Lett. 88, 247001 (2002).
[3]J.M. Tranquada et al., in press.
[4]I. Watanabe et al., J. Phys. Soc. Jpn. 61, 3058 (1992).
[5]I. Watanabe et al., Phys. Rev. B 65, R180516 (2002)[6]T. Adachi et al., Phys. Rev. B 69, 184507 (2004). •- 253 -

RIKEN Accel. Prog. Rep. 43 (2010)µSR study of iron-substitution eﬀects on the Cu-spin dynamics inthe overdoped regime of La2− x Srx Cu1− y Fey O4
T. Adachi,∗1 Y. Tanabe,∗1∗2 K. Suzuki,∗1 H. Sato,∗1 T. Suzuki,∗3 T. Kawamata,∗3 I. Watanabe,∗3
and Y. Koike∗1
is anomalously suppressed. Above 20 K, the spectrum shows Gaussian-like depolarization due to therandomly oriented nuclear spins. On the other hand,
fast depolarization of muon spins is observed below 20
K, followed by marked missing of the initial asymmetry at 1.9 K. The change of the spectra indicates thedevelopment of the magnetic correlation at low temperatures. Moreover, this result suggests a strong effect of the Fe substitution on the Cu-spin dynamics aswell as at p ∼ 1/8.5) The next step is to investigate
the p dependence of the spectra around x = 0.22.
In summary, we have found from ZF-µSR measurements fast depolarization of muon spins at low temperatures below 20 K for x = 0.225 and y = 0.01
in LSCFO where the superconductivity is anomalously suppressed. This suggests the development of
the stripe correlations through the Fe substitution in
LSCFO around x = 0.22. Therefore, there exists an
intimate relation between the stripe correlations andsuperconductivity in the overdoped LSCO.
References
1) N. Kakinuma et al.: Phys. Rev. B 59, 1491 (1999).
2) T. Kawamata et al.: Phys. Rev. B 62, R11981 (2000).
3) I. Watanabe et al.: Phys. Rev. B 62, R11985 (2000).
4) J. M. Tranquada et al.: Nature 375, 561 (1995).
5) M. Fujita et al.: J. Phys. Chem. Solids 69, 3167 (2008).
6) J. Arai et al.: J. Phys. Soc. Jpn. 66, 2875 (1997).
7) T. Adachi et al.: J. Phys. Soc. Jpn. 78, 025002 (2009).

1.2

La2-xSrxCu1-yFeyO4

1.0

Normalized Asymmetry

Since the early stage of the research of the high-Tc
superconductivity, much attention has been paid to thephysics in the overdoped regime. In particular, aroundx = 0.22 in the overdoped regime of La2−x Srx CuO4
(LSCO), signiﬁcant anomalies have been observed sofar; a slight depression of the superconducting (SC)transition temperature, Tc ,1,2) a development of the
Cu-spin correlation at low temperatures.3) These aresuggestive of a possible development of the so-called
stripe correlations of holes and spins4) around x =0.22, because these are analogous to those observed
around x = 1/8 where the stripe correlations are muchdeveloped.
Recently, Fujita et al. have revealed from the elastic neutron-scattering experiment that incommensurate magnetic and nuclear peaks are observed throughthe partial substitution of Fe with a large magnetic moment (Fe3+ : the spin quantum number S = 5/2) for
Cu in LSCO around the hole concentration per Cu,
p, = 1/8.5) As the superconductivity is strongly suppressed through the Fe substitution around p = 1/8,6)
it is suggested that the Fe substitution is eﬀective forthe stabilization of the charge-spin stripe order aroundp = 1/8.
Based on the above results, we have investigated Fe-substitution eﬀects on the electronic properties around x = 0.22 in the overdoped regime ofLa2−x Srx Cu1−y Fey O4 (LSCFO) from measurements ofthe electrical resistivity, ρ, and magnetic susceptibility.7) It has been found around x = 0.22 that ρ exhibits a pronounced upturn at low temperatures andthat Tc is anomalously depressed. These results suggest that the dynamical stripe correlations are stabilized by Fe, leading to the marked suppression ofsuperconductivity around x = 0.22 in LSCFO. Thisis, however, a very circumstantial conclusion deduced
from only the electronic properties. Therefore, in order to ﬁnd out a direct evidence for the Fe-induced
stripe order from the study of the Cu-spin dynamics,
we have performed zero-ﬁeld (ZF) µSR measurementsin the overdoped LSCFO. Polycrystalline samples of
LSCFO were prepared by the ordinary solid-state reaction method. The ZF-µSR measurements were carriedout at temperatures down to ∼ 2 K at RIKEN-RAL.
Figure 1 shows ZF-µSR time spectra of LSCFO withx = 0.225 and y = 0.01 where the superconductivity

x = 0.225
y = 0.01
20.5 K
15.0
12.0
10.1
9.1
8.1
1.9

0.8
0.6
0.4
0.2
0.0

0

2

4

6

8

10

Time (µ
µsec)
∗1
∗2
∗3

Department of Applied Physics, Tohoku University
WPI-AIMR, Tohoku University
Advanced Meson Science Laboratory, RIKEN Nishina Center

Fig. 1. Zero-ﬁeld µSR time spectra at various temperatures
for La2−x Srx Cu1−y Fey O4 with x = 0.225 and y = 0.01.

- 254 -

RIKEN Accel. Prog. Rep. 43 (2010)µSR study of the impurity-induced development of magnetic
correlation in the Bi-2201 high-Tc superconductor
T. Adachi,∗1 Y. Tanabe,∗1∗2 K. Suzuki,∗1 T. Suzuki,∗3 T. Kawamata,∗3 I. Watanabe,∗3 and Y. Koike∗1

∗1
∗2
∗3

Department of Applied Physics, Tohoku University
WPI-AIMR, Tohoku University
Advanced Meson Science Laboratory, RIKEN Nishina Center

Below 2 K, on the other hand, the spectrum changes
to exponential-like behavior and fast depolarization ofmuon spins is observed at 0.27 K. This change of thespectra indicates the development of the magnetic correlation at low temperatures. Moreover, this change
is quite similar to that observed in Zn-substituted
LSCZO,2,3) suggesting the possible development of the
stripe correlations also in Zn-substituted BPSCZO. As
for the p dependence, it is found that the fast depolarization is observed in the whole SC regime, though it
becomes weak gradually with increasing p. This suggests that the stripe correlations exist throughout the
SC regime.
In summary, we have found in ZF-µSR measurements fast depolarization of muon spins at low temperatures below 2 K in BPSCZO with y = 0.03 in awide range of p where the superconductivity appears.
This suggests the development of the stripe correlations in the monolayer Bi-2201 cuprate as well as in
the La-214 cuprate. Accordingly, the intimate relation
between the stripe correlations and superconductivity
might be concluded to be universal in various high-Tc
cuprates.
References
1) S. A. Kivelson et al.: Rev. Mod. Phys. 75, 1201 (2003).
2) T. Adachi et al.: Phys. Rev. B 69, 184507 (2004).
3) Risdiana et al.: Phys. Rev. B 77, 054516 (2008).
4) K. Kudo et al.: J. Phys. Soc. Jpn. 75, 124710 (2006).
5) I. Watanabe et al.: Phys. Rev. B 60, R9955 (1999).

1.2

Normalized Asymmetry

In the history of the high-Tc physics, the relationship between the magnetism and superconductivity
has been a central issue. In especial, the so-called
dynamical stripe correlations of spins and holes haveattracted considerable attention both experimentallyand theoretically.1)
Since 2001, we have performed systematic zeroﬁeld (ZF) µSR measurements in the whole superconducting (SC) regime of Zn-substituted La-214 cuprate
La2−x Srx Cu1−y Zny O4 (LSCZO) and have found out
an intimate relation between the stripe correlations
and superconductivity.2,3) However, one may doubt
the universality of this relation in various high-Tc
cuprates due to predominant eﬀects of the stripe correlations and the possible eﬀect of disorder in the CuO2
plane through the Sr substitution on various physicalproperties in La2−x Srx CuO4 .
The Zn-substituted monolayer Bi-2201 cuprate(Bi,Pb)2 Sr2 Cu1−y Zny O6+δ (BPSCZO) is one of thebest high-Tc systems showing almost all characteristics of the high-Tc superconductivity, i.e., the socalled pseudo-gap, quantum critical point and inhomogeneous SC state. Moreover, this is another highTc system in which the hole concentration can bechanged widely from the insulating lightly doped tonon-SC heavily overdoped regime controlling the excess oxygen content, δ, without large eﬀects of disorder.4) In the Zn-substituted double-layer Bi-2212
cuprate Bi2 Sr2 CaCu2−2y Zn2y O8+δ , on the other hand,
it has been suggested that Zn-induced development of
the magnetic correlation is observed but weaker thanthat in the La-214 cuprate,5) suggesting that eﬀects ofthe stripe correlations are weaker in the Bi-2212 thanin the La-214 cuprate. These results encourage us to
study the impurity-induced development of magnetic
correlation in BPSCZO.
Therefore, we have investigated Zn-substitution effects from µSR measurements in a wide range of holeconcentration per Cu, p, of BPSCZO. Polycrystalline
samples of BPSCZO with y = 0 − 0.03 were preparedby the ordinary solid-state reaction method. The µSR
measurements were carried out at temperatures downto ∼ 0.3 K at RIKEN-RAL.
Figure 1 shows ZF-µSR time spectra of the underdoped BPSCZO with p = 0.077 and y = 0.03.
Above 2 K, the spectrum shows Gaussian-like depolarization due to the randomly oriented nuclear spins.

Bi1.74Pb0.38Sr1.88Cu1-yZnyO6+δδ

1.0

y = 0.03
p = 0.077

0.8
0.6
20 K
2.0
1.1
0.5
0.27

0.4
0.2
0.0

0

2

4

6

Time (µ
µsec)

8

10

Fig. 1. Zero-ﬁeld µSR time spectra of (Bi,Pb)2 Sr2 Cu1−y Zny O6+δwith p = 0.077 and y = 0.03 at various temperatures
down to 0.27 K.

- 255 -

RIKEN Accel. Prog. Rep. 43 (2010)µSR study of the vortex state above Tc in high-Tc superconductors
T. Adachi,∗1 Y. Tanabe,∗1∗2 K. Suzuki,∗1 M. Akoshima,∗1 T. Suzuki,∗3 I. Watanabe,∗3 and Y. Koike∗1

∗1
∗2
∗3

Department of Applied Physics, Tohoku University
WPI-AIMR, Tohoku University
Advanced Meson Science Laboratory, RIKEN Nishina Center

the analysis function of A(t) = A0 GZ (∆, t) for the optimally doped BSCYCO with x = 0.2. The GZ (∆, t)
is the static Kubo-Toyabe function. With decreasing
temperature below 150 K, it is found that ∆ increases
gradually, followed by a steep increase below Tc . The
steep increase in ∆ below Tc is due to the large inhomogeneity of the local magnetic ﬁeld inside a sample
caused by SC vortices. On the other hand, the gradualincrease below 150 K is possibly due to the creation of
SC vortices and/or SC islands showing diamagnetism7)
in the SC ﬂuctuation state, which is consistent with theresult of STS in BSCYCO.8) Therefore, it appears that
SC vortices and/or SC islands exist even above Tc in
the optimally doped BSCYCO.
In summary, we have found from LF-µSR measurements of the optimally doped BSCYCO that the local ﬁeld at the muon site becomes inhomogeneous below 150 K far above Tc . This suggests the existenceof SC vortices and/or SC islands above Tc in high-Tc
cuprates.
References
1) S. H. Pan et al.: Nature 413, 282 (2001).
2) T. Adachi et al.: J. Phys. Soc. Jpn. 78, 114707 (2009).
3) Y. Tanabe et al.: J. Phys. Soc. Jpn. 74, 2893 (2005).
4) Y. Tanabe et al.: J. Phys. Soc. Jpn. 76, 113706 (2007).
5) Y. Wang et al.: Phys. Rev. B 76, 064512 (2007).
6) Z. A. Xu et al.: Nature 406, 486 (2000).
7) J. E. Sonier et al.: Phys. Rev. Lett. 101, 117001 (2008).
8) K. K. Gomes et al.: Nature 447, 569 (2007).

0.25

Bi2Sr2Ca1-xYxCu2O8+δδ
Distribution Width ∆ (µµ sec-1)

There have been an increasing number of studies
on the electronic state in high-Tc cuprates. Amongthem, the so-called electronic inhomogeneity in the
CuO2 plane has been one of recent interests in high-Tc
physics. In the underdoped regime, microscopic inhomogeneity of the superconductivity has been suggested
from the scanning tunneling spectroscopy (STS),1)
magnetic susceptibility, χ, and speciﬁc heat, C.2)
Moreover, a pseudo-gap state has been observed fromvarious kinds of measurements at high temperatures
above the superconducting (SC) transition temperature, Tc . One interpretation of these phenomena isthat strong-coupling superconductivity with a very
short coherence length is realized so that the SC ﬂuctuation is very large, leading to the pseudo-gap state
above Tc and the inhomogeneous SC state below Tc .
In the overdoped regime, on the other hand, the superconductivity was regarded as a homogeneous weakcoupling one as in the case of BCS-like conventional
superconductors. Recently, however, it has been suggested from χ3,4) and C 5) measurements in the overdoped regime of La2−x Srx CuO4 (LSCO) that a microscopic phase separation into SC and normal-stateregions takes place. When the separated two phasesin the overdoped regime consist of a hole-rich normal Fermi-liquid state region and a hole-poor strongcoupling SC one, a large SC ﬂuctuation is expected tobe observed above Tc even in the overdoped regime.
Although the existence of SC vortices above Tc dueto the large SC ﬂuctuation has been pointed out fromthe observation of a large Nernst eﬀect under magnetic
ﬁeld,6) the details have not yet been clariﬁed, because
the large Nernst eﬀect do not give a direct evidence forthe existence of SC vortices. On the other hand, µSR
measurements may be one of conclusive ways conﬁrming the existence of SC vortices, because µSR spectra
are sensitive to the inhomogeneity of the local magnetic
ﬁeld in a sample caused by SC vortices. Therefore, wehave investigated the possible existence of the SC vortices above Tc in LSCO and Bi2 Sr2 Ca1−x Yx Cu2 O8+δ(BSCYCO) from the underdoped to overdoped regime.
Polycrystalline samples of LSCO and BSCYCO wereprepared by the ordinary solid-state reaction method.
The µSR measurements were performed at temperatures below 300 K under zero ﬁeld, longitudinal ﬁeld
(LF) and transverse ﬁeld conditions at RIKEN-RAL.
Figure 1 shows the temperature dependence of the
distribution width of local ﬁelds at the muon site, ∆,estimated from the best ﬁt of LF-µSR spectra using

x = 0.2

0.20

0.15

0.10

Tc
0.05

LF = 20 G
0.00

0

50

100

150

200

250

300

T (K)

Fig. 1. Temperature dependence of the distribution widthof local ﬁelds at the muon site, ∆, estimated from LFµSR spectra using the function of A(t) = A0 GZ (∆, t)
for the optimally doped Bi2 Sr2 Ca1−x Yx Cu2 O8+δ withx = 0.2.

- 256 -

A2 (%)RIKEN Accel. Prog. Rep. 43 (2010)

Ru1.9Fe0.1CrSi
LF-μSRT = 0.26 K
Hint = 1308 ± 50 Oe

Normalized Asymmetry

HLF (Oe)

Ru1.9Fe0.1CrSi
LF-μSRT = 0.26 K
3950 Oe
2500 Oe

1500 Oe
600 Oe0 Oet (μs)- 257 -

RIKEN Accel. Prog. Rep. 43 (2010)

ALC-μSR Investigation of Model Porphyrins
I. Watanabe, A. Kikuchi, T. Suzuki, T. Kawamata, A. Stoykov, ＊1 and R. Scheuermann＊1＊1

Unfortunately, we did not observe a ny cl ear AL C
resonance signal in other samples that contained the Fe spinat the center of the porphyrin ring. In these samples, strong
depolarization be havior i s observed. We ar gue t hat t heabsence of the A LC sign al w ould be due to th e str ong
depolarization be havior of t he m uon s pin cause d by t hestrong fluctuation of Fe s pins. Th us, i t wa s im possible t oestimate the muon-stopping positions in those samples.
In order t o a void t his problem, we are planning t oprepare sam ples th at will have t he sam e stru cture as themeasured m odel p orphyrins but n o Fe s pin at t he ce nter
position. Since core stru ctures of model porphyrins are notvery di fferent from each other , we expe ct sim ilar ALC
signals for al l sam ples. C onsequently, we c an ass ume t hat
the locations of muons in al l model po rphyrin sam pleswould be th e same. If th is is th e case, we wou ld ab le todirectly co mpare th e fl uctuation frequ encies of th efluctuating internal field at the muon site.
We plan to ca rry out ALC- μSR measurement of the sesamples i n 201 0 at PS I usi ng t he sa me experi mental
apparatus. In addition to this experiment at PSI, we plan tomeasure the Fe-spin dynamics at the ISIS to determine thefluctuation frequency of eac h sam ple. We exp ect t hat t heresults of t hese expe riments wo uld cl arify the rel ationshipbetween local structures of heme and the functions of heme
proteins.

ALC Signal (au.)

The m ain pu rpose of t his stu dy is t o clarify th e
relationship between l ocal st ructures a round the central
metal i on, Fe, an d f unctions of hem eproteins be cause t hefunctions of hem eproteins vary wi th by not onl y their
3D-structures but also the electronic state around the Fe ion
in h emeproteins. Samples of m odel-porphyrins Fe( TPP)X(X = (Imidazole)2, Cl) a nd Fe(por)X (X = (Imidazole)2, Cl)
were prep ared. It should b e noted t hat th e latter con tained
protoporphyrin IX, which i s id entical to th e m oiety ofhemeproteins. The valence of Fe i on in all samples are 3+.
This means that these m odels are suitable for investigating
the “oxidized state” of hemeproteins.
In 2009, our main goal was to obtain information about
the l ocation of m uons i n m odel p orphyrins. B efore
considering the dynamics of Fe spi ns in model porphyrins,
it is i mportant to answer the following question; where aremuons located in porphyrin ? If t his pr oblem i s notaddressed, it would b e fu tile to carry out st udies t odetermine the spin dy
namics because the m uon-spin
depolarization behavior is determined by the magnitude andthe fl uctuation fre quency of the i nternal fi eld at t he m uonsite. In pat icular, t he f ormer de pends o n t he distance
between the muon and Fe spin. If the position of the muon
is different in each sample, it would be difficult to disc uss
the internal field from the Fe spin.
In order to satisfy th is requ irement, we studied an
Avoided Level Crossing (ALC) resonance measured at PSI
in Switzerland using a continuous muon beam. The injectedmuons stop at the potential minimum position in the sample
and sometimes form a charact eristic bound state wit hsurrounding e lectrons. I n such a case, t he surrounding
electrons i nduce hy perfine f ields at the muon site. Thesehyperfine fields affect resonance positions of the muon spinwhen e xternal m agnetic fi elds are ap plied. T hus, w hensuch resonance signals are observed in fiel ds, the c hemical
states of muons in materials can be discussed.
The m easurement has bee n pe rformed onl y at ro om
temperature a t the ALC a rea using a superconducting
magnet from zer o to ab out 3 T. Figu re 1 sho ws ALC
resonance signals of TPP model porphyrin, which does nothave Fe spin a t t he cent er o f t he porphyrin ri ng. We haveclearly observed four resonances in this sample. This resultmeans that t here are at least four m uon st opping-positions
thet have different chemical states in TPP. The depth of thesignal is ap proximately corresponds to the fraction of eachmuon st ate. T hus, m ost of muons f orm sim ilar chem ical
states with the signal main ALC resonance obtained at 0.75
T. In ord er to estim ate t he m uon-stopping position,
calculation of electric potential is required.

Magnetic Field (T)Figure 1: ALC resonances of TPP at the room temperature.

Bulk Muon Group, PSI, Villigen, Switzerland.

- 258 -

RIKEN Accel. Prog. Rep. 43 (2010)µSR study of structure-dependent electron radical dynamics inpolythiophene and its derivatives†
Risdiana,∗1 Fitrilawati,∗1 R. E. Siregar,∗1 R. Hidayat,∗2 A. A. Nugroho,∗2 M. O. Tjia,∗2 and I. Watanabe(1)where A1 and A2 are the initial asymmetries, and λ1
and λ2 are the depolarization rates for fast and slow
components, respectively. The LF dependence of λreflects the dimensionality of the diffusion of the spinexcited state. That is, λ is proportional to H−0.5 forone-dimensional (1D) intrachain diffusion and C-H0.5
for three-dimensional (3D) interchain diffusion2) .
Figure 1 shows the LF dependence of λ1 in RdmP3HT and RR-P3OT. For comparison, the results obtained for RR-P3HT are also displayed. In the lower
panels, λ1 indicates the H−0.5 field-dependent characteristics of 1D intrachain diffusion, implying that the
charge transport is dominated by the mobility of thecharge carriers along the polymer chain. With an increase in temperature, the charge carriers, which initially follow 1D intrachain diffusion, move by 3D interchain diffusion, as characterized by the field dependence of λ1 , which could be well fitted by the C-H0.5
curve, as shown in the upper panels. The initial change
in the carrier mobility appeared to have occured at∗1∗2

Department of Physics, Padjadjaran University, Indonesia
FMIPA, Bandung Institute of Technology, Indonesia

References
1) Risdiana et al.: RIKEN Accel. Prog. Rev. 42 (2009)256.
2) M. A. Butler et al.: J. Chem. Phys. 64 (1976) 3592.
3) T. Chen et al.: J. Am. Chem. Soc. 117 (1995) 233.

-1

A(t) = A1 exp(−λ1 t) + A2 exp(−λ2 t),around 25 K to 50 K, 50 K to 75 K, and 50 K to 75
K, in RR-P3HT, Rdm-P3HT, and RR-P3OT, respectively. A similar behavior was observed in the LFdependent variation of λ2 . However, the values of λ2
were two orders of magnitude smaller than those of λ1 .
The present results revealed a remarkable shift in therelative dominance between the intra and interchain
charge transport, which depends on the regioregularity and side-chain length of the polymers. Comparison between regioregular and regiorandom in P3HT
revealed that interchain diffusion is facilitated at hightemperatures for regiorandom polymer system. Whilea thorough explanation of this difference cannot begiven on the basis of the current experimental results,
this difference is thought to be related to the difference in the bandgaps between regioregular and regiorandom P3HT. A regioregular structure is known tohave a small bandgap (1.7 eV), which is 0.4 eV smaller
than that of a regiorandom structure3) . Because of thesmall bandgap, the thermal excitation energy required
to support the interchain charge transport is supposedly smaller, and hance, crossover observations can be
carried out at a low temperature for regioregular structures. Comparison of the difference in the side-chain
lengths of RR-P3HT and RR-P3OT showed that theinterchain polaron diffusion process in RR-P3OT is favored at high temperatures. This high-temperaturedependence may be related to the difference in the interchain distance betweern RR-P3HT and RR-P3OT.
Clearly, a longer side-chain results in a longer interchain distance, which in turn indicates the need for ahigh thermal energy to support interchain hopping.

λ1 (µ sec )Among the various conducting polymers available,
polythiophene (PT) and its derivatives have been studied extensively because of their chemical and thermal
stability, as well as their existing and emerging applications in various fields. In particular, extensive
studies have been carried out on the PT derivativepoly(3-alkylthiophene) (P3AT) because the physicaland chemical properties of this derivative can be effectively modified by varying the alkyl-side-chain length.
Transport measurements performed on P3AT have revealed a strong dependence of the conductivity of
P3AT on its molecular structure such as regioregularity (regioregular (RR) and regiorandom (Rdm)).
Previously, we studied the microscopic chargetransport processes in RR-poly(3-hexylthiophene-2,5diyl) (RR-P3HT) by performing longitudinal-field
Herein, we report(LF) µSR measurements1) .
the temperature-dependent spin diffusion dynamics of the charge-carrying polarons in Rdm-poly(3hexylthiophene-2,5-diyl) (Rdm-P3HT) and RR-poly(3octylthiophene-2,5-diyl) (RR-P3OT) observed along
the alkyl chain and in the direction perpendicular to
the alkyl chain. The diffusion dynamics were studied
by the LF-µSR method for the purpose of determining
the relative contributions of intrachain hopping andinterchain coupling to the charge-transport process inthese polymers. All the time spectra could be wellfitted by the two-component function below:

101
100
10-1
101
100
10-1
101
100
10-1

(a) RR-P3HT(b) Rdm-P3HT

300 K(c) RR-P3OT
300 K

50 K

75 K

75 K

25 K

50 K

50 K

300 K

101 102 103 101 102 103 101 102 103

HLF (mT)Fig. 1. Longitudinal-field dependence of λ1 in RR-P3HT(a), Rdm-P3HT (b), and RR-P3OT (c).

- 259 -

RIKEN Accel. Prog. Rep. 43 (2010)

Study of dynamics of amorphous polymer by performing µSR
measurements
T. Kanaya,∗1 R. Inoue,∗1 I. Watanabe, and T. Matsuzaki,
In order to understand the unresolved problem ofglass transition and related dynamics, we have studied
the dynamics of a glass-forming polymer using μ SR.
We used polybutadiene (PB) with molecular weight
Mw of 2.8 × 105 and molecular weight distribution(Mw /Mn ) = 1.15. Its glass-transition temperature(Tg ) was 170 K. The µSR measurements were performed at RIKEN-RAL, and the focus was mainly on
the dynamic properties of PB Hence, we performed
longitudinal ﬁeld (LF) measurements with a 100-G
magnetic ﬁeld at temperatures ranging from 10 K to300 K, which included Tg . In order to evaluate the accurate relaxation rate, we also performed careful deadtime correction of the obtained time-dependence results. Figure 1 shows the decay of the asymmetry for
PB at 10 K, 180 K (which was quite close to Tg ), and
300 K With increasing temperature, we can observe a
Fig. 2. Temperature dependence of the decay rate for PB.
Lines are shown in order to clearly observe the onset ofrelaxation.

Fig. 1. Time dependence of the decay of asymmetry for PB
at 10 K, 180 K, and 300 K under a LF of 100 G.

very clear increase in the relaxation rate very clearly,
suggesting the acceleration of dynamics with temperature. In order to analyze the relaxation rate, we ﬁtted
the obtained time-dependence data with a single exponential function. It appears that a single exponentialfunction can describe the experimental results reasonably at temperatures below and above Tg . The temper∗1

ature dependence of the decay rate is shown in Figure
2. At present, we don’t know the physical signiﬁcanceof the small peak observed at around 50 K; apart fromthis peak, the relaxation rate increased with temperature monotonically. We can observe a steep increasein the relaxation rate above 180 K (which is near toTg ), suggesting that glass transition was detected byµSR. In addition to the detection of glass transition,
we also observe a small increase in the relaxation rate
at around 120 K. This temperature corresponds to theonset temperature of the local motion of a so-called
fast process. In principle, the time scale of this fast
process is about picosecond (ps); hence, it is quite surprising that μ SR can successfully detect such a local
motion as well. The temperature dependence of therelaxation rate is quite similar to that of the meansquare displacement < u2 > that is evaluated from inelastic neutron scattering. By studying the results of
μ SR and inelastic neutron scattering, we can obtaina better understanding of the dynamics of amorphous
polymer on a wide-time scale. We are currently trying
to evaluate the temperature dependence of heterogeneous relaxation time and rates by ﬁtting a stretchedexponential curve to the spectrum. Further analysis isin progress.

Institute for Chemical Research, Kyoto University- 260 -

RIKEN Accel. Prog. Rep. 43 (2010)

Diﬀusion of muon in hydrogen tungsten bronze
M. Mihara,∗1 K. Shimomura,∗2 I. Watanabe, D. Nishimura,∗1 J. Komurasaki,∗1 T. Suzuki, Y. Ishii,
T. Kawamata, W. Sato,∗3 T. Nakano,∗1 K. Nishiyama,∗2 R. Kadono,∗2 S. Takai,∗4 M. K. Kubo,∗5 andH. Matsue∗6

25

490 K

Asymmetry (%)

20

450 K

10 K
15

110 K

370 K

410 K

210 K

10

5

0

0

5

10

15

t ( s)

20

25

Fig. 1. Typical ZF-µSR spectra in Hx WO3 .
∗1
∗2
∗3
∗4
∗5
∗6

Department of Physics, Osaka University
Institute of Materials Structure Science, KEK
Department of Chemistry, Kanazawa University
Department of Materials Science, Tottori University
The College of Liberal Arts, ICU
Quantum Beam Science Directorate, JAEA

30

(s-1)

107

106

Fluctuation rate

Hydrogen tungsten bronze Hx WO3 has important
applications in electrochromic (EC) devices in which
the dark-blue colored (x > 0) and bleached (x ≈ 0)states of the devices are reversibly controlled by applying an electric ﬁeld. In order to use a WO3 -based
EC device in thin ﬁlm displays, a short response time of
the EC device must be achieved1) and the basic property of hydrogen diﬀusion in Hx WO3 must be understood. We performed the positive muon spin relaxation(µSR) measurements, which are potentially useful forthe study of hydrogen diﬀusion; we considered a muon
to be a light isotope of proton.
Figure 1 shows the typical ZF-µSR spectra ofHx WO3 measured at the RIKEN-RAL muon facility.
The hydrogen content x = 0.4−0.5 was estimated bya neutron-induced prompt γ-ray analysis (PGA)2) ofa test sample that was prepared by following the sameprocedure as the one for preparing the sample used in
the present µSR experiment. The spectra of Hx WO3
are characterized by a Gaussian damping, which is incontrast to the exponential-like relaxation observed forpure WO3 3) . The relaxation curves obtained at T <350 K were well-reproduced by a static Kubo-Toyabe(KT) function that was multiplied by an exponential
relaxation factor ∼KT(∆, t)e−λt . The Gaussian distribution width ∆ was nearly constant at around 0.09
µs−1 at temperatures between 10 and 350 K, though
the value of λ, which is about 0.03 µs−1 at T < 100

105

104
1.5

2.0

2.5

3

3.0

-1

10 /T (K )

3.5

4.0

4.5

Fig. 2. Fluctuation rate for muons in Hx WO3 , as deduced
from the ZF-µSR data. The solid circles denote thepresent results (x = 0.4−0.5) and the open circles represent the previous results for H0.22 WO3 3) . The dottedline represents the proton NMR results for H0.39 WO3 4) .

K, decreases with increasing temperature and becomesalmost 0 at around 300 K. The value of ∆ is almost
consistent with that estimated by taking into consideration the nuclear dipolar ﬁeld of the protons in
Hx WO3 . Motional narrowing eﬀect occurred at T >350 K since the relaxation rate rapidly reduced withincreasing temperature. This is considered to be dueto the dynamic behavior of muons.
The dynamic properties of muons in Hx WO3 wasdetermined from the data obtained at T > 350 K. The
ﬂuctuation rate of the internal ﬁeld ν, which is considered to be the muon hop rate, was deduced by the χ2
ﬁtting procedure using a dynamic KT function KT(∆,t, ν) with ∆ ﬁxed at 0.09 µs−1 . The deduced preliminary result for the ﬂuctuation rate ν is shown in Fig.
2; the results of the previous ZF-µSR measurements
for H0.22 WO3 3) and the proton NMR line widths of
H0.39 WO3 4) are also shown in this ﬁgure.
References
1) H. Yoshimura et al.: Jpn. J. Appl. Phys. 45, 3479
(2006).
2) H. Matsue and C. Yonezawa: BUNSEKI KAGAKU 53,
249 (2004).
3) M. Mihara et al.: Physica B 404, 801 (2009).
4) P.G.Dickens et al.: J. Solid State Chem. 6, 370 (1973).

- 261 -

 RIKEN Accel. Prog. Rep. 43 (2010)


Measurement of the Mössbauer γ-rays from exotic Fe atoms producedby µ--capture reactions
Y. Kobayashi, M. K. Kubo,1 K. Ninomiya,2 K. Ishida, and M. Iwasaki
Products of nuclear reactions and radioactive decays havebeen extensively studied for several decades. The large
amount of energy available to the atom following a nuclear
event induces exotic chemical and physical changes thatcannot be achieved by ordinary thermal, electric,mechanical, or electromagnetic excitations. The formationof anomalous chemical species by hot-atom reactions in gas
and liquid phases has been extensively studied and clarified.
However, the characteristics of the unstable species
produced in solid-state hot-atom reactions are not yet
completely understood. Therefore, the development of
non-destructive characterization methods is necessary to
clarify the anomalous chemical states of an atom created by
the nuclear events.
Emission Mössbauer spectroscopy has a high sensitivity
and can be used to characterize extremely small amounts ofany species formed during or after nuclear events; it does
not require any chemical treatment of the sample. In
particular, the in-beam Mössbauer spectra can be measured
simultaneously while inducing the excited states by nuclear
reaction or by implantation of nuclear probes. We havesuccessfully measured the neutron in-beam Mössbauer
spectra of Fe compounds. The obtained results suggested
that thermally unstable and exotic Fe chemical species areformed immediately after the completion of a neutroncapture reaction1).
It is well known that exotic atoms are produced following
negative muon (µ-) capture or neutron capture in hot-atom
reaction. Backenstoss et al. evaluated the distribution of theexcited nuclei formed after µ --capture process anddetermined the probabilities of the evaporation of neutrons
by identifying the γ-rays emitted in the excited states2).
They reported that excited states of 57Fe* are obtained in thereaction 59Co(µ-, 2n)57Fe* Co metal target. It is expectedthat the nuclear probes formed by µ --capture possess thelarge amount of energy associated with neutron recoil. It is
important to use the in-beam Mössbauer technique tounderstand the chemical states of 57Fe* that results from theµ--capture process. As per our knowledge, the formation of
excited nuclei after µ - capture has not been used in
Mössbauer studies or other materials science studies. In thisexperiment, the µ --capture process has been used in the
study of hot-atom chemistry for the first time.
The experiment was performed at Port-1 in the
RIKEN-RAL muon facility. A Co foil with a thickness of
200 µm was set at the target position in the beamline. The
γ-rays and muonic X-rays emitted as a result of µ - capture
1
2

were detected by Si(Li) and pure Ge detectors. First, it wasdetermined whether negative muon (30 MeV/c) stopped in
the Co target. γ-peaks were observed at 285 keV, 1341 keV(from µCo), and 810 keV (from 58Fe) using the Ge detector.
Next, the momentum dependence of 122-keV γ-transition
intensity in a thinner Co foil was measured. The 122-keV
γ-transition is a precursor of Mössbauer γ-ray, and it isnecessary to reduce the thickness of the target because of
the low energy of the 14.4-keV Mössbauer γ-ray. Figure 1
shows the energy spectra of the Co metal target foil that
captured µ- with a momentum of 20.4 MeV/c. Although thepeak intensities were not sufficient, it was consistent with
the intensity ratio of the 14.4-keV transition to the 122-keVtransition considering that the internal conversion
coefficient is 8.2. The µ --beam intensity and theconfiguration of thin Co target will be optimized further for
improved in-beam Mössbauer measurements.

122 keV
14.4 keV

Energy (keV)

Energy (keV)

Fig. 1. Energy spectra of Co that captured negative muonwith the momentum of 20.4 MeV/c. The Co foil was
sandwiched between two Al degraders with a thickness of
30 µm (upstream) and 45 µm (downstream), respectively.
(a) 14.4-keV Mössbauer γ-transition and (b) 122-keVtransition resulting from the formation of the excited states
57
Fe*.

References
1) Y. Kobayashi et al.: Hyp. Int. 187, 49 (2008).
2) G. Backenstoss et al.: Nucl. Phys. A 162, 541 (1971).

Division of Natural Science, International Christian University
Japan Atomic Energy Agency- 262 -

RIKEN Accel. Prog. Rep. 43 (2010)

Muon Transfer Studies in Solid D2 with Implanted Rare-Earth Ions
P. Strasser,∗1 A. Taniguchi,∗2 S. Ohya,∗3 T. Matsuzaki, K. Ishida, Y. Matsuda,∗4 M. Iwasaki, and
K. Nagamine∗5[Muonic atom spectroscopy, solid hydrogen ﬁlm, ion implantation]

∗1
∗2
∗3
∗4
∗5

50

(a)

µ148Sm2p

Counts / 1.5 keV

40

2p

1/2

→ 1s

3/2

→ 1s

1/2

1/2

30

20

10

0
4250

4300

4350

4400

4450

4500

4550

Delayed Energy [keV]
140

(b)

2p → 1sµ152Sm120
100

Counts / 1.5 keV

The cold hydrogen ﬁlm method1) was proposed toapply muonic atom spectroscopy to nuclear beams, including radioactive isotope (RI) beams, with the aimof producing muonic radioactive atoms in the future.
This would enable RI studies by the muonic X-ray
method at facilities in which both intense µ− and RI
beams will be available. The basic idea is to simultaneously stop both µ− and nuclear beams in a solidhydrogen ﬁlm, followed by the direct muon transfer reaction to higher Z nuclei to form muonic radioactive
atoms. An experimental program to perform muon
spectroscopy with stable ions implanted in a solid D2
ﬁlm is in progress at the RIKEN-RAL muon facility. A
new surface ion source was installed on the µA* apparatus with the goal of using RI in the future. Ions fromalkali and alkaline-earth elements can be produced very
eﬃciently. Results have already been reported2) fromtransfer experiments performed with isotopically separated 88,87,86 Sr ions. 138,137 Ba were also measured.
The new surface ion source can also produce ionsfrom rare-earth elements that ideal candidates for an
experiment to study very high Z nuclei with deformation properties. For instance, samarium isotopes
show very abrupt changes in their nuclear characteristics from spherical to highly deformed nuclei. 144 Sm
is magic in neutrons and displays the characteristics
of stiﬀ spherical nuclei, which are very hard to excite,whereas 152 Sm and 154 Sm reveal low energy levels characteristic of highly deformed nuclei whose muonic Xray spectra show a 2p hyperﬁne structure (hfs). The
latest measurements were performed with isotopicallyseparated Sm ions utilizing the same procedure as that
followed previously to implant Sr and Ba ions2) . Figure
1 shows the delayed energy spectra measured by the Ge
detector with 1-mm-thick pure D2 and about 1 ppm of148
Sm and 152 Sm ions implanted non-uniformly. This
experiment was performed using natural samarium oxide (Sm2 O3 ) in the ion source, and only about 6 × 1016
Sm ions in the D2 ﬁlm. The measured isotope shift isconsistent with that observed in previous experiments
performed using enriched Sm isotopes3,4) . 148 Sm still
has a spherical nucleus, while 152 Sm clearly shows the
2p hfs characteristic of highly deformed nuclei.
At present, the experimental accuracy is limited essentially for statistical reasons related to the relatively

2+

2+

80
60
40
20
0
4250

4300

4350

4400

4450

4500

4550

Delayed Energy [keV]

Fig. 1. Delayed spectrum of the 2p→1s muonic transitionsin Samarium measured with 1-mm-thick pure D2 andabout 1 ppm of (a) 148 Sm and (b) 152 Sm ions implanted
non-uniformly. The arrows show the most intense lines.
The transitions where the 152 Sm nucleus was excited to
the 2+ level as the muon reached the 1s state are shown.

low µ− beam intensity at 27 MeV/c, making the comparison with other measurements involving enrichedstable isotopes in very large quantities diﬃcult. Future
intense muon facilities with higher muon ﬂux would
improve the statistics and also require fewer implanted
ions. The advantages of this method with stable isotopes are that the isotope separation can be achieved
during the implantation and that high-purity isotopes
can be measured. Further, it is free from the chemicalcomposition of the element if it can be fully ionized.
References

Muon Science Laboratory, IMSS, KEK
Research Reactor Institute, Kyoto University
Department of Physics, Niigata University
Graduate School of Arts and Sciences, University of Tokyo
University of California Riverside, CA, USA- 263 -

1) P. Strasser et al.: AIP Conf. Proc. 793, 242 (2005).
2) P. Strasser et al.: RIKEN Acc. Prog. Rep. 41 (2007);RIKEN Acc. Prog. Rep. 42 (2008).
3) D. Hitlin et al.: Phys. Rev. C 1, 1184 (1970).
4) R.J. Powers et al.: Nucl. Phys. A 316, 295 (1979).

RIKEN Accel. Prog. Rep. 43 (2010)

Progress in the analysis of muon beam density enhancement eﬀect
observed when using tapered tubes
D. Tomono, T.M. Kojima, T. Ikeda, K. Ishida, Y. Iwai, M. Iwasaki∗1 , Y. Kanazawa∗2 ,Y. Matsuda∗3 , T. Matsuzaki, M. Tokuda∗1 and Y. Yamazaki∗3
Generation of highly intense muon beams is currently an important issue in µSR studies and highdensity muonium formation for slow-muon generation
at RIKEN-RAL. Since the sample or target used inthese studies is usually very small when compared tothe beam size (approximately 40 mm), a number ofmuons are stopped by the collimator at the end of thebeamline. By optimizing inner shape of the collimator, the number of muons available can be increased,
as in a capillary technique: charged particles can beeﬀectively focused by a tapered glass tube, which defects them at the inner wall surface and guides them tothe outlet. A previous experiment at RIKEN-RAL1)
showed that when a tapered glass tube is coaxiallyaligned with the muon beam, the 54-MeV/c pulsed
muon beam is partly scattered at the inner wall surface and muons are directed to the outlet by a Coulomb
force; as a result, the number of available muons is almost twice that in the case of using a normal beamcollimator. In addition, after the upgrade of the proton accelerator, muon beams that are 1.5 times more
intense have been generated. By combining this technique and upgrade, we can obtain beams that are atleast three times as intense as the previously generated
beams. In order to understand muons scattering at the
inner wall for practical applications, a new experiment
was started using the continuous beam at the M9B
beamline, TRIUMF, Canada. In-ﬂight-decay muons
whose momentum ranged from 30 MeV/c to 50 MeV/c
were employed. The experimental setup and detector
details have been included in a previous report2) . The
purpose of this study is to determine the energy andangular distribution of the outgoing muons by identifying each incoming muon with the continuous beam.
In addition, density enhancement eﬀect is expected todepend on the material of the tapered tube; this eﬀect
is more pronounced when heavy metals such as copperand gold are used instead of glass, probably because of
the large Coulomb scattering coeﬃcient in the formercase. For simplicity, metal and glass capillary plates
were prepared instead of capillary tubes. This article
includes the preliminary results of the energy distribution in the case of copper plates observed by lithiumdrifted silicon detector (SSD, ORTEC TL-045-200-5).
Figure 1 shows a photograph of the outlet of the
∗1
∗2
∗3
∗4

RIKEN and Tokyo Institute of Technology
Department of Physics, Sophia University
Graduate School of Arts and Sciences, University of Tokyo
RIKEN and Graduate School of Arts and Sciences, University of Tokyo

Fig. 1. Photograph of the setup around the outlet of theplates and the SSD detector.

Fig. 2. Muon energy distributions at the outlet of the capillary plates (line) and of the slit (dashed line) for reference.

plates and the SSD (thickness: 5 mm; detection area:
16 mm� ). Although the plate material, plate outlet
width, SSD position, and array counter position could
be varied during the measurements under the present
conditions, the SSD was positioned 10 mm downstreamof the 20-mm-wide plate outlet. Further, a slit wasinserted instead of a plate as a reference for comparison with the case where there was no density enhancement. The muon beam was ﬁrst identiﬁed by a start
counter (T1) placed upstream of the plates. Sinceother particles entering the same time window of 15µs
could distort the energy spectra because of pile-up signals or accidental background hits, only one muon injection was guaranteed to reject background particles
along with the beam under naive analysis conditions;
event at the initial time of muon injection and a single
hit event to the T1 counter were chosen in the time
window.
Figure 2 shows the preliminary results of the energy
distribution in the SSD at the 20-mm-wide outlet ofthe copper plates and slit for 40-MeV/c muons; theresults are normalized by the number of events in the
SSD. The obtained results suggest that the scatteredmuons have lower energy than the initial muons andthus result in a low-energy tail. This might provide
information about the stopping range distribution forpractical µSR studies. Presently, all recorded data arebeing analyzed for a quantitative understanding of theplates and experimental conditions.
References- 264 -

1) T.M. Kojima et.al.:J. Phys. Soc. Jpn. 76, 093501(2007).
2) D. Tomono et. al.:RIKEN Accel. Rep. 43, 261(2009).

3.

Radiochemistry and Nuclear Chemistry

RIKEN Accel. Prog. Rep. 43 (2010).

Production of an isomeric state of 261Rf by the 248Cm(18O,5n)261Rf reaction
H. Haba, D. Kaji, Y. Kasamatsu, H. Kikunaga,*1 Y. Komori,*1 Y. Kudou, K. Morimoto, K. Morita, K. Ooe,*1 K. Ozeki,
A. Shinohara,*1 T. Sumita,*2 and A. Yoneda*1

Graduate School of Science, Osaka University*2

Graduate School of Science, Tokyo University of Science

50

30
20

8.52 261Rfb

40

7.687 214PoCounts / 40 keV

8.28 261Rfa,
8.22, 8.32 257No

60

7.150, 7.192 254Fm

Previous studies of the 208Pb(70Zn,n)2771121,2) andCm(26Mg,5n)269Hs3) reactions have shown the existenceof an isomeric state 261Rfb (half-life T1/2 = 3 s, α energy Eα =8.51 MeV, Spontaneous Fission branch bSF = 0.91) of 261Rf(261Rfa: T1/2 = 68 s, Eα = 8.28 MeV, bSF < 0.11).4) However,so far, 261Rfb has not been directly observed as anevaporation residue. Recently, Gorshkov et al.5) successfully
produced 261Rfb by the 244Pu(22Ne,5n) reaction at GSI
Helmholtzzentrum für Schwerionenforschung GmbH. The
Rf atoms were separated with TASCA (TransActinide
Separator and Chemistry Apparatus) and transported to
ROMA (Rotating wheel On-line Multidetector Analyzer) by
a He/KCl gas-jet system. A total of eleven SFs wereassigned to 261Rfb on the basis of the measured T1/2 of
2.2+0.9–0.5 s, though no 8.51-MeV α was observed. In
RIKEN, we have been developing a gas-jet transport system
coupled to RIKEN GARIS (GAs-filled Recoil Ion
Separator) for use in experimental studies in the field ofsuperheavy element chemistry. Recently, 261Rfa wasproduced by the 248Cm(18O,5n) reaction and was extracted
by the gas-jet to a chemistry laboratory after physicalseparation by GARIS.6) Alpha particles of 261Rfa wereclearly identified using the rotating wheel system MANON
for α spectrometry under extremely low backgroundconditions. In this work, we investigated the production anddecay properties of 261Rfb using the GARIS/gas-jet system.
A 248Cm2O3 target with a thickness of 230 μg cm–2 was
prepared by electrodeposition onto a Ti foil with a thicknessof 0.91 mg cm–2. An 18O5+ ion beam was extracted from the
RIKEN Linear Accelerator, RILAC. The beam energy was
95.1 MeV at the center of the target, and the average beam
intensity was 7 pμA. The reaction products of interest wereseparated in-flight from the beam and the majority of thenuclear transfer products by GARIS and then guided into
the gas-jet chamber through a Mylar window of 0.5 μm
thickness, which was supported by a honeycomb grid with
84% transparency. GARIS was filled with He gas at 33 Pa
and its magnetic rigidity was set at 1.72 Tm. The
transmission of GARIS was 8% for 261Rfa.6) The reaction
products were then transported by the He/KCl gas-jet to
MANON in the chemistry laboratory with an efficiency of~50%.6) In MANON, the KCl aerosols were deposited on
200-position Mylar foils of 0.5 μm thickness placed at the
periphery of a wheel with a diameter of 420 mm. The wheel
was stepped at 1.67-s intervals to position the foils between
seven pairs of Si PIN photodiodes (Hamamatsu S3204-09).
248

10
0

7

8

9

10

11

12

Energy / MeV

Fig. 1. Sum of α-particle spectra measured in the seven top
detectors of MANON.
Figure 1 shows the sum of α-particle spectra measured in
the seven top detectors of MANON. A beam dose of 3.2 ×
1018 was accumulated. It is to be noted that an α-peak isclearly observed at 8.52 MeV together with those of 261Rfa
and its daughter 257No (24.5 s, 8.22 and 8.32 MeV)4) at
8.00–8.43 MeV. Totally, twenty-one 8.52-MeV α-eventswere registered, and the half-life was determined to be 1.6 ±0.6 s. Six time-correlated α-events on the 8.52-MeV α were
found in the energy window ≥ 7.90 MeV and in the time
window ≤ 250 s. The energies of the correlated α ranged
from 8.18 MeV to 8.31 MeV, and the half-life deduced
from the decay times was 22+14–6 s. These decay properties
agree well with those of 257No. In addition, sixty SF eventswith T1/2 = 2.1±0.6 s were also registered. In this work, theisomeric state of 261Rfa, 261Rfb, was successfully confirmed
directly in the 248Cm(18O,5n) reaction. The α-energy andhalf-life of 261Rfb are determined to be 8.52 ± 0.03 MeV and
1.9 ± 0.4 s, respectively. This half-life agrees well with that
(2.2+0.9–0.5 s) reported in Ref.5) The bSF of 261Rfb is 0.74 ±0.06. The cross section (σ) of 261Rfb was evaluated to be 11± 2 nb by assuming the cross section of 261Rfa to be 12 nb7)
and the gas-jet transport time to be 2.7 s. The σ ratio of261
Rfa to 261Rfb (1.1 ± 0.2) is smaller by a factor of two thanthat (~2.5) in the 244Pu(22Ne,5n) reaction.5)
References

1) S. Hofmann et al.: Eur. Phys. J. A 14, 147 (2002).
2) K. Morita: J. Phys. Soc. Jpn. 76, 043201 (2007).
3) J. Dvorak et al.: Phys. Rev. Lett. 100, 132503 (2008).
4) C. E. Düllmann and A. Türler: Phys. Rev. C 77, 064320 (2008).
5) Gorshkov et al.: GSI Sci. Rep. 2008, 140 (2009).
6) H. Haba et al.: Chem. Lett. 38, 426 (2009).
7) Y. Nagame et al.: J. Nucl. Radiochem. Sci. 3, 85 (2002).

- 265 -

RIKEN Accel. Prog. Rep. 43 (2010)

Experiment on electrochemical oxidation of nobelium using a
microchannel-electrode chip
K. Ooe,*1 Y. Komori,*1 H. Fujisawa,*1 A. Kuriyama,*1 R. Takayama,*1 Y. Kikutani,*1 H. Kikunaga,*1 T. Yoshimura,*1 N.
Takahashi,*1 H. Haba, Y. Kasamatsu, Y. Kudou, Y. Ezaki, and A. Shinohara.*1
Redox studies of heavy elements with atomic numbers
greater than 100 are interesting because the redox potential
clearly corresponds to the energy level of the valence state,
which is significantly influenced by strong relativistic
effects. Recently, the oxidation of element 102, nobelium(No), by an electrochemical approach has been reported by
Toyoshima et al.1). In their experiments, an electrochemical
apparatus was combined with ion exchange column
chromatography, and No2+ was successfully oxidized to
No3+. As another method for studying the electrochemistryof the heavy elements, we employed a microchip integrated
withelectrodes(hereafterreferredtoasa
microchannel-electrode chip). Because various chemical
processes can be integrated on a microchip, it is expectedthat the redox operation can be carried out along withsolvent extraction by using a microchannel-electrode chip.
In the present study, as a first step towards carrying out an
on-chip redox reaction along with solvent extraction, we
performed electrochemical oxidation of No2+ using a
microchannel-electrode chip.
The layout of the glass-substrate microchannel-electrodechip (custom-made by the Institute of Microchemical
Technology) is shown in Fig. 1. The dimensions of the
microchannel are 2 mm (width) × 15 μm (depth) × 60 mm(length). The Pt/Ti electrodes were used as working andcounter electrodes. The lengths of the working and counterelectrodes are 50 mm and 4 mm, respectively. A thin Ag
layer electrodeposited onto the Pt/Ti electrode was used as a
pseudo-reference electrode.2) Although this chip has two
identical microchannels, only one side of the microchannel
was used in the following experiments.
The experiment on No oxidation was performed using the
RIKEN K70 AVF Cyclotron. The isotopes 255No (T1/2 = 3.1
min) and 163Yb (T1/2 = 11.05 min) were simultaneously
produced via the 248Cm(12C,5n) and natGd(12C,xn) reactions,
respectively. The reaction products recoiling out of thetarget were transported by a He/KCl gas-jet transportsystem to a chemistry laboratory. The transported products
were collected on a Naflon sheet for 5 min and were thendissolved in 1 μL of 0.1 M HNO3. The solution was drawn
up by a syringe and fed into the microchannel-electrodechip at a flow rate of 3.5 μL/min. The potential applied to
the working electrode was 500 or 1250 mV with respect to
the Ag pseudo-reference electrode. The effluent from themicrochannel-electrode chip was collected in a
polypropylene tube for 140 s, and 43 μL of 0.1 M HNO3
*1

Department of Chemistry, Osaka University

was added to the effluent. The solution was mixed with 50
μL of 0.5 M di(2-ethylhexyl) phosphoric acid in CCl4
solution and the mixture was shaken for 1 min at 30 ºC toseparate No3+ from No2+. After centrifugation, 40-μL
aliquots of the aqueous and organic phases were separated
and evaporated to dryness on Ta discs. These samples were
subjected to α-spectrometry for 10 min using Si PIN
photodiode detectors. Ytterbium-163 was used to monitor
the chemical behavior of the trivalent ion. The extraction
behavior of No2+ and Yb3+ was also investigated in separate
experiments carried out using a batch extraction method.
In the batch extraction experiments, the extraction
efficiency of No2+ was about 7%, while that of Yb3+ wasmore than 99%. Therefore, this extraction system caneffectively separate No3+ from No2+. In the oxidation
experiment at an applied potential of 1250 mV, fourα-events in the case of 255No in the aqueous phase and six
α-events in the organic phase were observed. On the other
hand, at an applied potential of 500 mV, 14 α-events in thecase of 255No in the aqueous phase and 1 α-event in theorganic phase were detected. Thus, No2+ was successfully
oxidized to No3+ at an applied potential of 1250 mV. In thisexperimental condition, 1250 mV with respect to the Ag
pseudo-reference electrode corresponds to approximately
1600 mV with respect to the normal hydrogen electrode(NHE). The redox potential of No was reported as 1.4–1.5
V with respect to the NHE by Silva et al.3). The present
result is consistent with their result. In the future, thedependence of the oxidation efficiency of No2+ on theapplied potential will be investigated for the determining
the redox potential of No2+/No3+ in 0.1 M HNO3.

Inlet

OutletCounter electrode Reference electrode Working electrodeFig. 1. Structural layout
microchannel-electrode chip.
References

of

the

glass-substrate

1) A. Toyoshima et al.: J. Am. Chem. Soc. 131, 9180 (2009).
2) C. D. T. Bratten et al.: Anal. Chem. 69, 253 (1997).
3) R. J. Silva et al.: J. Inorg. Nucl. Chem. 31, 3405 (1969).

- 266 -

RIKEN Accel. Prog. Rep. 43 (2010)
このテンプレートはカメラレディ用のフォーマットではありません。文字数制限については「執筆要領」を合わせてご参照下さい。
This template is not a camera-ready format. Please refer to Authors Guide for the total number of characters.
Liquid scintillation counting of 261Rf produced in 248Cm(18O,xn) reaction andpreseparated using RIKEN GARIS/gas-jet system

Y. Komori,＊1 K. Ooe,＊1 H. Fujisawa,＊1 R. Takayama,＊1 H. Kikunaga,＊1 T. Yoshimura,＊1 N. Takahashi, ＊1
H. Haba, Y. Kudou, Y. Kasamatsu, and A. Shinohara＊1
In order to perform chemical experiments involving
superheavy elements (SHEs), a rapid and efficientchemistry apparatus is required because of the shorthalf-lives and low production rates of SHEs.
Liquid scintillation (LS) counting has been used for thedetection of α particles in studies of aqueous chemistry ofSHEs because it has high detection efficiency and does not
require time-consuming evaporation steps for sample
preparation.1) However, LS counting is also sensitive to βparticles and γ rays in addition to α particles. Further, theenergy resolution is not sufficient to identify α events ofSHEs from the large amount of α, β, and γ radiations
originating from by-products. In order to remove theseby-products, which are unwanted, a technique has beendeveloped for the physical preseparation for SHE atoms.1,2)
In the RIKEN linear accelerator (RILAC) facility, a gas-jet
system has been installed behind the gas-filled recoil ion
separator (GARIS) to transport pre-separated SHE atoms to
the chemistry laboratory.3,4)
We are planning to develop a liquid-liquid extraction
system with LS counters coupled with the preseparator
GARIS/gas-jet system. In this work, we evaluate theapplicability of the LS counting system to the identificationof 261Rf on the basis of the observation of a time-correlated
α pairs originating from 261Rf and from its daughter 257No,
which are reaction products preseparated and transported by
the GARIS/gas-jet system; the α pairs are measured by the
LS counter.
261
Rf, the most used nuclide for studying Rf chemistry,
was produced in the 248Cm(18O, 5n) reaction. The 18O5+ ion
beam was extracted from RILAC. The beam energy was
95.1 MeV at the center of a 248Cm2O3 target. The reaction
products that were preseparated by GARIS were attached to
KCl aerosol particles and then transported through a Teflon
capillary in the gas-jet system to the chemistry laboratory.4)
Samples for LS counting were prepared as follows. The
aerosol particles were deposited on a polyethylene
terephthalate film for 2 min and were then dissolved in 100µL of dilute HCl solution (pH 3.1). The HCl solution was
mixed with 900 µL of a water-miscible scintillation cocktail
in a 10 mmφ×75 mm Pyrex culture tube. A blank sample
for use in LS counting was also prepared by mixing 100 µLof radioactivity-free HCl solution with 900 µL of thescintillation cocktail.

These samples were measured using a PERALS®
spectrometer (ORDELA, Inc), which is capable ofperforming pulse shape discrimination (PSD) to distinguishbetween α and β events. The energy resolution wasapproximately 550 keV FWHM for 241Am. During theexperiment, polyethylene blocks were used to shield thespectrometer from fast neutrons because fast neutron events
overlap with α-particle events in a pulse shape spectrum.
The aerosol particles were deposited on a glass filter for 5
min and then subjected to γ-ray spectrometry using a Ge
detector.
In the LS α spectrometry, the counting rate of β particles
in the sample was comparable to that in the blank sample. A
total of 12 counts in 14 run, 7495 s of measurement time,
were observed in the region where the 261Rf events were
expected. These α counts are considered to originate from261
Rf and 257No, other α emitters in the transported products,
fast neutrons, or noise of the LS spectrometer. In order to
identify time-correlated α pairs from 261Rf and 257No,
successively observed events in a time interval of 125 s,
which is five times the half-life of 257No, were identified. As
a result, four decay sequences were attributed to thetime-correlated α pairs from 261Rf and 257No. The mean
lifetime of the 2nd α decay is 27 s. The background countrate for α events under the present conditions wasdetermined by excluding the α pairs of 261Rf and 257No fromthe observed α counting rate and was found to be (5.3 ±2.7)×10-4 cps. The probability of the random correlation
evaluated from the background count rate for α events isevaluated to be 0.01%. In the γ spectra, only prompt γ raysfrom neutron-capture reactions were observed. Thisobservation indicates that no γ-emitting nuclides weretransported with the aerosol particles. These results showthat LS counting can be used to identify the time-correlated
α pairs from 261Rf and 257No by using the GARIS/gas-jet
system.
References

1) J. P. Omtvedt et al.: J. Nucl. Radiochem. Sci. 3, 121 (2002).
2) C. E. Düllman et al.: Eur. Phys. J. D 45, 75 (2007).
3) H. Haba et al.: J. Nucl. Radiochem. Sci. 9, 27 (2008).
4) H. Haba et al.: Chem. Lett. 38, 426 (2009).

＊1

Department of Chemistry, Graduate School of Science, Osaka
University- 267 -

RIKEN Accel. Prog. Rep. 43 (2010)- 268 -

RIKEN Accel. Prog. Rep. 43 (2010)- 269 -

RIKEN Accel. Prog. Rep. 43 (2010)

Hydroxide coprecipitation of Zr and Hf with Sm: Model experiment for thechemical study of Rf
Y. Kasamatsu, H. Haba, Y. Ezaki, Y. Kudou and K. Morita
Chemical studies o n transactinide el ements with atomic
numbers Z ≥ 104 are currently at the frontier in inorganicand nuclear chemistry. Transactinide e lements must b e
produced at accel erators u sing heavy-ion-induced nuclear
reactions. Chemical studies of these elements are conducted
on a one-atom-at-a-time basis by rapid chemical separation
techniques because o f the low pr oduction r ates a nd s horthalf-lives (T1/2 ≤ 1 min) of these elements. For unambiguous
identifications of th ese e lements existing as one atom at atime, it i s n ecessary t o d etect α or s pontaneous f ission
decays and t o measure t he half-lives of t hese el ements.
Thus, chemical characterization of tramsactinide elements
is not o nly fascinating but also challenging. Thus far,mainly from th e r esults o f gas-phase a nd aqueous-phase
chromatographic experiments, it has been found that thesetransactinide elements with atomic numbers up to 108
belong to t he set o f transition metal elements (d-orbital) in
the 7t h pe riod. However, the chemical p roperties o f th eelements have not been clarified in detail.
Recently, the anion- and cat ion-exchange b ehaviors of
rutherfordium (Rf, Z = 104) in HF and HF/HNO3 solutions
were successfully investigated in detail at the Japan Atomic
Energy Agency Tandem Facility, and the behavior of Rf wasreported to be clearly different from that of the homologues
Zr a nd H f.1) Detailed studies o n Rf in various chemicalsystems must be carried o ut for a deeper understanding of
its chemical properties. The purpose of the present study is
to establish a new experimental method for investigating theformation o f the hydroxide complex of 261Rf ( T1/2 = 68 s ).
Since Rf can be treated as only one atom at a time, we muststudy the coprecipitation b ehavior o f R f with a carrierelement. Coprecipitated samples with samarium hydroxide,
which facilitated the α spectrometry with a high e nergy
resolution, were p repared by K ikunaga et al .2) usingalumina-membrane filters. Therefore, by using this method,
we i nvestigated t he h ydroxide co precipitation b ehavior o f
Zr and Hf with Sm in order to carry out the Rf experiment.
We produced carrier-free radiotracers 88Zr (T1/2 = 83.4 d)and 175Hf (T1/2 = 70.0 d) in the 89Y/natLu(p, xn) reactions in
the RIKEN K 70 AVF c yclotron. The r adiotracers werechemically p urified b y an anion-exchange method a nd
finally dissolved in 6 M HCl solution. The hydroxide
coprecipitates o f Zr an d Hf with S m were p repared byadding 20 µg o f S m a nd b asic s olutions with various
compositions (conc. NH3 water, 0.1, 1, a nd 6 M N aOH
solutions) to th e hydrochloric solutions, which c ontained
trace am ounts o f Zr and Hf (108–109 atoms), until t hesolution was al kalified (the concentrations o f the basic
solutions obtained were ab out 3 M NH3 water, 0.08, 0 .8,

and 3 M NaOH, respectively). The precipitates were s oon
filtered w ith the alumina filters, and the preparations w ere
completed within 1 min. Then, the s amples w ere dried a t
100 °C using a heater and were subjected to γ-ray
measurement with a G e d etector. On t he o ther hand, thereference r adioactivity o f t he r adiotracers was also
determined by the γ-ray measurement. From the ratio of themeasured radioactivities of the precipitates to the reference
radioactivity, th e yield o f eac h precipitate was d etermined.
The d ependence of t he yields on t he compositions of thebasic solutions is depicted in Fig. 1.
It was found that almost the entire amounts of Zr and Hf
are co precipitated w ith S m when NH3 water a nd 0 .1 M
NaOH are used. This shows the well-known property of Zr
and Hf, i.e., formation of a neutral hydroxide complex a nd
precipitation in basic solutions. The results suggest that theformation o f hydroxide c omplexes of Z r a nd H f issufficiently rapid and that precipitation is complete within 1
min. For more concentrated NaOH solutions, however, t heyields decrease as t he co ncentration increases. This isprobably because the formation of hydroxide complexes of
Zr a nd H f pr oceeds further in the co ncentrated N aOH
solutions; Z r a nd H f form a nionic hydroxide complexes.
For a ll s amples, the y ields of S m were ~ 100% as
determined b y the α-particle measurement. As a result, thebehaviors of Zr and Hf were observed to be similar under
all conditions. It is very interesting to study how Rf behaves
under the present experimental conditions.
We are planning to prepare the first hydroxide precipitateof R f and t o i nvestigate the formation o f t he a mmine
complexes and the hydroxide complexes of Rf.

Fig. 1 . Variation o f th e yields ofthe hy droxide
coprecipitation of Zr and Hf according to the compositionsof the basic solutions.
References

1) Y. Ishii et al .: Chem. L ett. 37, 28 8 (2008), an d r eferences
therein.
2) H. Kikunaga et al.: Appl. Radiat. Isot. 67, 539 (2008).

- 270 -

RIKEN Accel. Prog. Rep. 43 (2010).

Study of the reversed-phase chromatographyof element 104, rutherfordium (Rf) with TIOA or TTA extractant
M. Araki,＊1 T. Nanri,＊1 Y. Takeda,＊1 M. Nishio,＊1 M. Nishikawa,＊1
Y. Kasamatsu, Y. Ezaki, Y. Kudou, H. Haba, and A. Yokoyama＊2＊1

Faculty of Science and Graduate School of Natural Science andTechnology, Kanazawa University＊2
Institute of Science and Engineering, Kanazawa University

graphy.
Figure 1 shows typical elution curves of Zr, Hf, and Y in
0.0029 M HF/0.1 M HNO3 solutions obtained by using the
1.6 mmφ teflon tube. The separation of Zr, Hf, or Y fromthe others achieved is as shown in Fig.1. Distribution ratios
were derived from the curves on the basis of a formuladeveloped by Glückauf for chromatography.
Figure 2 shows the variation of D of Zr and Hf obtainedby the batch method and the column chromatography as afunction of the equilibrated concentration of F- ([F-]eq). The
dependence of the variation of D on [F-]eq observed using
the column method corresponds well to that observed using
the batch method as well as its magnitude relation between
the elements. This demonstrates that the chemical systemsof this study are more suitable to be applied to the Rfexperiment for investigating the strength of F- complexationcompared to that of the other group-4 elements.

Relative activity

0.4
Stripping

0.3

●Zr

0.2

▲Hf

0.1

■Y

0
0

0.2

0.4 0.6
Volume / mL

0.8

1

Fig. 1. Typical elution curves for Zr, Hf, and Y with
TTA-resin.
Distribution ratio / mL g-1

In order to investigate a chemical property of Rf, which
is a superheavy element of group 4, we have studied the
distribution ratios (D) in liquid-liquid systems for column
chromatography under static conditions with resin
containing TTA (2-thenoyltrifluoroacetone) or TIOA
(Tri-iso-octylamine) extractant, which may clarify therelevant chemical species and provide the complex
formation constants. Introduction of this chemical system
for the Rf experiment with AIDA (Automated Ion exchange
separation apparatus coupled with the Detection system for
Alpha spectroscopy) is discussed in this study.
A TTA support material Kel-F (42－80 mesh), which is apolychlorotrifluoroethylene copolymer, was used to preparea TTA resin for performing reversed-phase chromatography.
Batch experiments were carried out to determine the Dvalues for Zr and Hf in chemical equilibrium with TTA
resin. The resin with 30-wt% TTA (30－50 mg) and 3 mLof 10－4 – 10－1 M HF/0.1 M HNO3 containing 50 µL of 88Zr
and 175Hf carrier-free tracer solution were mixed andallowed to attain equilibrium in a polypropylene tube for 15
min at 20 ○C. After centrifugation, 2 mL of the aqueous
layer was pipetted into another polyethylene tube andsubjected to γ-ray spectrometry using a Ge detector.
Off-line reversed-phase extraction chromatography of88
Zr and 175Hf was performed with a teflon tube column (1.6mmφ) or a microcolumn (1.6 mmφ × 7 mm). The 30-wt%
TTA-resin was filled into the column. The radiotracers of88
Zr and 175Hf were deposited on a collection site. Then, thetracers were dissolved in the mixed HF/HNO3 solutions andfed into the column at a flow rate of 0.5 mL min -1. The
effluent was collected in 7－15 polypropylene tubes inorder to obtain their elution curves. The remaining Zr and
Hf in the column were finally stripped with 0.1 M HF/0.1
M HNO3 at a flow rate of 0.5 mL min -1. The effluent wascollected in two polypropylene tubes. These fractions wereassayed by γ-ray spectrometry using a Ge detector.
On-line reversed-phase extraction chromatography of89m
Zr and 175Hf was performed with a teflon tube or a
micro-column. The nuclides of 89mZr and 175Hf were
simultaneously produced in the 89Y(p, n) and 175Lu(p, n)reactions, respectively, at the RIKEN K70 AVF Cyclotron.
The reaction products were transported by a He/KCl gas-jet
system, and collected for 300 s. The subsequent procedures
are the same as those of off-line reversed-phase chromato-100
50●Zr (off-line)○Zr (on-line)-□- Zr ( batch)

10
5
1 -5
10

▲Hf (off-line)△Hf (on-line)

-

10-4

-▽- Hf ( batch)[F ]eq / M
Fig. 2. Variation of the distribution ratios (D) of Zr and Hf
for column chromatography under static conditions as afunction of the equilibrated concentration of F- ([F-]eq). Thelines drawn joining the batch data are eye guides.

- 271 -

RIKEN Accel. Prog. Rep. 43 (2010)

Use of solvent-extraction apparatus with microchemical chip inheavy-element chemistry
H. Fujisawa,∗1 K. Ooe,∗1 Y. Komori,∗1 A. Kuriyama,∗1 R. Takayama,∗1 Y. Kikutani,∗1 H. Kikunaga,∗1 T.
Yoshimura,∗1 N. Takahashi,∗1 H. Haba, Y. Kasamatsu, Y. Kudou, Y. Ezaki, and A. Shinohara∗1∗1

Department of Chemistry, Graduate School of Science, Osaka University

MCC, V is replaced by the ﬂow rate. In Fig. 2, thevalues of log D for strontium, which is a divalent cation
like nobelium, are plotted as a function of pH in the
aqueous phase. The D values obtained by using theapparatus were consistent with those obtained in thebatch experiments.
The online experiment involving the extraction ofnobelium was performed using the apparatus describedabove. The 255 No (T1/2 = 3.1 min) isotope was produced in the 248 Cm(12 C, 5n) reaction at the RIKENAVF Cyclotron. In this experiment, the AIDA system2) was used for α-detection. The time elapsed between from the dissolution of the reaction products
and the start of the measurement was approximately
4 min. Thus, we have obtained the D value of nobelium in the extraction system, although thoroughcorrections such as those for cross-contamination between aqueous and organic phases are required. To
perform chemical experiments on superheavy elementswith atomic numbers greater than 104, we will further
improve the present apparatus for carrying out rapid
chemical experiments.
Organic solution Microchip extraction

Evaporation with IR heater
Alpha detection(AIDA)

Dissolution unit Aqueous solution
Collection

Switching gas-jet line

sliderGas exhaust
Collection site
He/KCl gas-jet

Nuclear reaction
products

He/KCl gas-jet

BeamAqueous solution

Transportation
by He/KCl gas-jet

Fig. 1. Schematic diagram of the automated solventextraction apparatus.

1.5

logD

Studies of the chemical properties of superheavy
elements and heavy actinides with atomic numbers
greater than 100 require rapid analytical techniqueswith repeatability because of the low production rates
and short lifetimes of these nuclides. Thus far, we haveso far developed a solvent-extraction technique involving the use of a microchemical chip (MCC), and wehave successfully applied this technique in an online
experiment1) . In this study, we have automated anapparatus with MCC and use it in solvent-extraction
experiment for nobelium.
Figure 1 shows a schematic diagram of the developed solvent extraction apparatus. Nuclear reaction
products are transported to the chemistry laboratory
by a He/KCl gas-jet transport system. The transported products are deposited on the collection siteof a polychlorotriﬂuoroethylene slider, are dissolved inaqueous solution, and are then subsequently fed into
an MCC (ICC-DY15, Institute of Microchemical Technology Co., Ltd.). An organic solution is fed from theother inlet of the MCC. The aqueous and organic efﬂuents from the MCC are separately collected on Ta
discs. After the samples are evaporated, they are subjected to α-spectrometry using Si detectors. The seriesof the operations is automated by using a LabView system (National Instruments Co.).
Oﬀ-line tests of this apparatus were carried out using
multitracers produced at the RIKEN Ring Cyclotron
and single radiotracers produced at the RCNP AVF
Cyclotron in Osaka University. The radiotracers werestored in acetic acid/ammonium acetate solutions witha pH of approximately 5.8. Batch experiments were
performed as follows. Hundred microliters of the aqueous solution with various pH values and 100 µL of 0.01
M di(2-ethylhexyl) phosphoric acid-CCl4 solution weremixed in a test tube. The mixture was shaken for 10
min using a vortex mixer and was then centrifuged
for 2 min. After phase separation, each phase was assayed for γ-radioactivity. In the oﬀ-line extractions
performed by utilizing the apparatus, the same solutions as those in batch experiments were used. Aqueous and organic solutions were fed into the MCC at a
ﬂow rate of 5 µL/min. Each phase from the MCC was
separately collected in test tubes and was assayed for
γ-radioactivity.
The distribution ratio D is obtained from the equation D = Vaq Aorg /Vorg Aaq , where V represents volume and A represents radioactivity. In the case of the1

0.5‫ ۑ‬batch experiments‫ ڦ‬apparatus tests
0
5.4

5.6

5.8
pH

6

6.2

Fig. 2. Plot of log D vs. pH for strontium with 0.01 M
di(2-ethylhexyl) phosphoric acid.

References
1) K. Ooe et al.: J. Nucl. Radiochem. Sci. 8, 59 (2007).
2) H. Haba et al.: J. Nucl. Radiochem. Sci. 3, 143 (2002).

- 272 -

RIKEN Accel. Prog. Rep. 43 (2010)

Basic study of solvent extraction system with FIA for superheavy element
chemistryY. Kudou, Y. Ezaki, H. Haba, Y. Kasamatsu, and K. Morita

DG

R2

P

PR
EU

E (%) ,(1)
where Aaq and Aorg are the radioactivities in the aqueous andorganic phases, respectively. In Fig. 2, the extraction
percentages obtained by a batch method and the FIA system
are shown for (a) 88Zr and (b) 175Hf as a function of HClconcentration. The extraction percentages obtained using
the FIA system agree well with those obtained by the batch
method for the 11.5 M and 10.0 M solutions; however, inthe case of the 7.0 M solutions, the extraction percentage
obtained using the FIA system is less than that obtained by
the batch method. In separate experiments, it is found thatthe percentages obtained by using the FIA system for the
7.0 M solution becomes close to that obtained by the batch
method when the flow rate is decreased and the extraction
unit is elongated. The total time taken for the online
experiments is approximately 1 min. Therefore, this system
can be applied to 261Rf, which has a half-life of 74 s. The
system proposed in this paper is considered to be feasible
for SHE experiments after adequate optimization of theexperimental conditions.
(a)

PS

(b)

100

100

Org. ph.

Fig. 1. Schematic diagram of the solvent extraction / FIAsystem. R1: HCl solution (11.5 M, 10.0 M, and 7.0 M), R2:
toluene solution containing 50 wt% TBP, S: tracer solution,
EU: extraction unit packed with PTFE chips (i. d.: φ2 mm,
length: 10 cm), DG: degasser, P: double plunger pump(flow rate: 0.5 cm3 min-1), I: six-way valve that acts as asample injector, PS: phase separator using a PTFE
membrane filter, PR: pressure regulator, Aq. ph.: aqueous
phase, Org. ph.: organic phase.

100 Aorg

Aaq  Aorg

Extraction percentage / %I

R1

The HCl solution and the toluene solution were propelledby the double plunger pump (P). A solution containing 88Zr
and 175Hf was introduced into the aqueous phase byswitching the flow channel with the six-way valve (I). The
solutions were mixed by using a T-connector and introduced
into the extraction unit (EU) packed with PTFE chips(ca.1.0 × 1.0 × 0.5 mm), which were obtained by
cutting a PTFE tube into pieces of the desired dimensions.
The phases were separated by the phase separator via a
PTFE membrane filter (pore size: 0.8 m). Pressure
regulators (PR) were newly installed downstream of boththe phases in order to achieve efficient phase separation.
After the separation, the aqueous and organic effluents wereseparately collected in polyethylene tubes and analyzed by
-ray spectrometry.
The extraction percentage E was calculated by using thefollowing equation:

Extraction percentage / %Chemical investigation of superheavy elements (SHEs,
atomic numbers Z ≥ 104) is of considerable interest
because their chemical properties are strongly influenced byrelativistic effects.1) The solvent extraction method iscommonly used to investigate the chemical properties ofSHEs, especially the complexation equilibrium constants,
which are indicative of the chemical-bonding nature, so thatthese relativistic effects can be well understood. However,since SHEs have short half-lives and very low production
rates, ordinary solvent extraction methods should be
improved on a one-atom-at-a-time basis. Flow-injection
analysis (FIA) makes it possible to perform a series ofanalytical operations in a continuous flow, such as
pretreatment, separation, and detection. FIA is a suitable
candidate for a solvent extraction system that facilitates
rapid reactions for the SHE chemistry. Itabashi et al.2)
succeeded in developing an FIA system for accelerating theextraction process, by using a polytetrafluoroethylene(PTFE) tube packed with PTFE chips as an extraction coil;the PTFE chips help increasing the specific interfacial areaand shortening the diffusion length. In this paper, we report
the performance and applicability of this FIA system and its
applicability to the SHE chemistry.
Using this system, we examined the solvent extraction
behaviors of 88Zr and 175Hf (homologues of Rf (Z = 104)) ina test experiment performed on Rf. Radiotracers 88Zr (t1/2 =83.4 d) and 175Hf (t1/2 = 70.0 d) were produced in the 89Y (p,2n)88Zr and natLu (p, xn)175Hf reactions, respectively; thesereactions were carried out in the RIKEN K70 AVF
cyclotron. 11.5 M, 10.0 M, and 7.0 M solutions of thesetracers in HCl were prepared and stored polypropylene
containers. The HCl solutions were used as the aqueous
phase, while a toluene of tributyl phosphate (TBP; 50 wt%)
was used as the organic phase for solvent extraction. A
schematic diagram of the solvent extraction system isshown in Fig. 1.
S
Aq. ph.

80

60
40□: 88Zr (batch)○: 88Zr (FIA system)

20
0
6

7

8

9

10

11

HCl concentration / M

12

80
60
40

△: 175Hf (batch)◇: 175Hf (FIA system)

20
0
6

7

8

9

10

11

12

HCl concentration / M

Fig. 2. Difference in the extraction percentages obtained by
the batch method and the FIA system for (a) 88Zr and (b)175
Hf as a function of HCl concentration (n = 3).
References
1) M. Schädel: Angew. Chem. Int. Ed. 45, 368 (2006).
2) H. Itabashi and Y. Mesuda: J. Flow Injection Anal. 20, 193(2003).

- 273 -

RIKEN Accel. Prog. Rep. 43 (2010)

Mutual separation of short-lived lanthanides by capillaryelectrophoresis
H. Kikunaga,∗1 T. Yoshimura,∗1 T. Kuribayashi,∗1 Y. Kitamoto,∗1 N. Takahashi,∗1 H. Haba, Y. Ezaki,
S. Enomoto,∗2 T. Mitsugashira,∗3 and A. Shinohara∗1

∗1
∗2
∗3

Department of Chemistry, Graduate School of Science, Osaka University
Graduate School of Medicine, Dentistry and Pharmaceutical
Science, Okayama University
International Research Center for Nuclear Materials Science,
Institute for Materials Research, Tohoku University

from the lanthanide multitracer, except for Tb, Dy, Ho,and Er. The lanthanides moved in ascending order of
the atomic number. Figure 2 shows the electrophoretic
mobility as a function of the reciprocal ionic radius(coordination number (CN) = 8). The solid line in
Fig. 2 is the electrophoretic mobility simulated on thebasis of the stability constants for the complexes oflanthanides with 2-hydroxyisobutyrate and acetate2) .
The mobility of lanthanides is in good agreement withthe simulated value. Although there is still room for
improving the chemical yield, the present system will
can be used to study the properties of heavy actinides.
0.8
Pm Sm Eu

0.7

Tb

Er
Y
Dy
Ho

0.6

Yield

Lu
0.5

Yb

0.4

Tm

0.3
0.2
0.1
0

300

350

400

450

500

550

600

Elapsed Time / s

Fig. 1. Electrophoretogram of yttrium and trivalent lanthanides.


For studying of the chemical properties of heavy actinides with atomic numbers greater than or equal to≥ 100, rapid analysis techniques with high-resolution
are required because of the low production rates andshort lifetimes of these nuclides. We have successfully applied capillary electrophoresis to 152 Dy (T 1/2= 2.37 h) produced in the nat Ce(16 O, xn) reactions1)
for the rapid isolation of the element. In this study, we
have applied this method for the mutual separation oflanthanides with lifetimes shorter than that of 152 Dy,namely, 150m Tb (T1/2 = 5.8 min), 154 Ho (T1/2 = 11.8min), and 157 Er (T1/2 = 18.7 min).
A lanthanide-multitracer solution was prepared asfollows. Radiotracers were produced in the 197 Au(14 N,
X) reactions at the RIKEN Ring Cyclotron. The Au
target was dissolved in aqua regia and then heatedto dryness. The residue was dissolved in 2 M HCl
and passed through an anion exchange resin column(Dowex 1×8, 200-400 mesh) to eliminate the Au target material from the lanthanide fraction. The anion
exchange procedure was repeated using a fresh column.
The lanthanide fraction was heated to dryness and adjusted to pH 3.
The isotopes 150m Tb, 152 Dy, 154 Ho, and 157 Er were
produced in nuclear reactions that involved a 120 MeV
16
O beam supplied from the AVF cyclotron at the
RCNP in Osaka University. A target that was a mixture of La, Ce, Pr, and Nd was prepared by electrodeposition onto titanium backing foil. The reaction products recoiling from the targets were continuously transported to a chemistry laboratory by using a He/KCl
gas-jet transport system. The reaction products were
deposited on a polyethylene terephthalate ﬁlm and dissolved in 2 µL of the lanthanide-multitracer solution.
The solution was injected into the anode side of afused silica capillary, which was ﬁlled with an electrolyte solution (12 mM 2-hydroxyisobutyric acid, 350
mM acetic acid, and 10 mM creatinine). A voltage of+30 kV was applied across the capillary with platinum
electrodes at room temperature. The separated lanthanides were fractionated by a tailor-made apparatus
and assayed for radioactivity by γ-ray spectrometry.
Figure 1 shows electrophoretogram of yttrium andtrivalent lanthanides. These elements were derived











 






































 

Fig. 2. Electrophoretic mobility as a function of the reciprocal ionic radius (CN = 8).

References
1) T. Kuribayashi et al.: RIKEN Accel. Prog. Rep. 41,
213 (2007).
2) T. Hirokawa et al.: J. Chromatogr. 312, 11 (1984).

- 274 -

4.

Radiation Chemistry and Biology

RIKEN Accel. Prog. Rep. 43 (2010)

The effects of trichostatin A on DNA damage response after X-ray irradiation inhuman cells
M. Izumi
In eukaryotes, DNA is packaged into nucleosomesthat are in turn arranged in various high-order structures toform chromatin. The chromatin structure is regulated bychromatin-associated factors and histone modifications suchas acetylation, methylation, and phosphorylation. The
chromatin structure influences many aspects of DNA
metabolism including replication, recombination, andtranscription. However, it is not fully understood how
chromatin structure influences DNA double-strand break(DSB) repair and how chromatin structure is altered in
response to DNA damage.
The clinical trials for evaluating histone deacetylase(HDAC) inhibitors as anticancer drugs are in progress. 1)
HDAC inhibitors exhibit anticancer effects by causing theaccumulation of acetylated histones, which relaxes thechromatin structure and activates tumor suppressor genes.
In addition to their intrinsic anticancer activity, HDAC
inhibitors are synergistic with radiotherapy, 2)3) although
the mechanism by which HDAC inhibitors enhance theradiation sensitivity of human cells remains unknown.
To examine the roles of chromatin structure in DNA
repair and investigate the potential of HDAC inhibitors incombination with heavy-ion radiotherapy, I have been
investigating the damage response initiated after treatmentof cells with the HDAC inhibitor trichostatin A (TSA). In
the previous study, I have examined the effect of TSA on
the phosphorylation of histone H2AX 4). Histone H2AX isa histone variant and is rapidly phosphorylated at the sitesof DSBs by ionizing radiation. 5) I have found that the
pretreatment of normal human fibroblast NB1-RGB cellswith 0.1 µM TSA for 5 h increased the amount ofphosphorylated histone H2AX (γ-H2AX) by 2.5-fold at 1 h
after irradiation. This result suggests that the relaxed
chromatin structure facilitates the repair response byimproving damage recognition or changing thesusceptibility of DNA to radiation.
Herein, I have investigated the effect of low (0.1 µM)
and high (1 µM) concentrations of TSA in HeLa cells.
The pretreatment with TSA did not increase the γ-H2AXlevels before irradiation (data not shown). At 1 h after
irradiation, the amount of γ-H2AX was elevated by 1.8-fold
at 0.1 µM and 2.3-fold at 1 µM respectively (Fig. 1). This
result indicates that the effect of TSA was dose dependent.
Next, HeLa cells were pretreated with TSA andimmunostained with anti-γ-H2AX antibody at 1 h after
irradiation (Fig. 2). The intensity of immunofluorescenceof individual γ-H2AX foci in TSA-treated cells was muchhigher than that in the control cells. On the other hand, thenumber of foci in TSA-treated cells was similar to that in
the control cells. Therefore, the increase of γ-H2AX level
was mainly due to the facilitated damage response and not
due to the increase in DSB.

Now, I am investigating whether TSA affects themutation rate and survival of HeLa cells after irradiation.
Further, I am investigating whether TSA has the same effecton the damage response after heavy-ion irradiation.

Fig. 1 The effect of TSA at different concentrations. A,
HeLa cells were treated with 0.1 or 1 µM of TSA for 5 h
and then irradiated with 10 Gy of X-ray using Radioflex.
Whole cell extracts were prepared at the indicated time
points after irradiation and subjected to immunoblotting.
Glyceloadehyde-3-phospho dehydrogenase (GAPDH) was
detected as the loading control. B, the intensity of eachband was measured using luminoimage analyzer LAS3000(Fuji Film) and normalized against the amount of GAPDH.
Bar graphs represent mean ± SD of 4 independent
experiments.
0 µM

1 µM

Fig. 2 The pretreatment with TSA increased the intensityof immunofluorescence of γ-H2AX foci. HeLa cells weretreated with 1 µM TSA for 5 h and then irradiated with 5
Gy of X-ray. After 1 h, the cells were fixed withethanol/acetic acid, and γ-H2AX was detected by indirect
fluorescent staining.
References
1) R. L. Piekarz et al.: Blood 103, 4636 (2004).
2) Y. Zhang, et al.: Radiat. Res. 161, 667 (2004).
3) K. Camphausen et al.: Clin. Cancer Res. 10, 6066 (2004).
4) M. Izumi: RIKEN Accel. Prog. Rep. 42, 249 (2009).
5) C. Thiriet and J. J. Hayes: Mol. Cell 18, 617 (2005).

- 275 -

RIKEN Accel. Prog. Rep. 43 (2010)

Cell-killing eﬀect of low dose of high-LET heavy ions (III)M. Tomita,∗1 T. Tsukada, and M. Izumi
The radiation-induced bystander response is deﬁned
as a response in cells that have not been directly targeted by radiation but that are in the neighborhoodof cells that have been directly exposed.1) In space,astronauts are exposed to low ﬂuencies of high-LET(linear energy transfer) radiation. In heavy-ion cancer therapy, normal cells surrounding a tumor are also
exposed to heavy ions. Therefore, the bystander responses induced by low doses of high-LET radiation
are an important problem in radiation biology. In ourstudy, we aim to clarify the molecular mechanisms andbiological implications of bystander responses induced
by low doses of high-LET radiation. Previously, we
had reported that normal human ﬁbroblasts that were
irradiated with low doses of high-LET Fe ions showed
low-dose hyper-radiosensitivity (HRS), suggesting that
bystander cell killing was induced.2,3) In order to enable a functioning bystander response, at least two
signaling pathways should be functional: one pathway is through direct physical interaction between cells
such as in the case of gap-junction intercellular communication (GJIC), and the other is through the interaction between the cells and the culture medium.4)
In addition, it was suggested that reactive nitrogenspecies (RNS) and reactive oxygen species (ROS) aremolecules that play an important role in bystander signaling.4) Recently, we reported that the bystander cellkilling induced by synchrotron X-ray microbeam irradiation was mainly mediated by nitric oxide (NO).5)
Now, we are studying the role of NO in the HRS induced by low doses of high-LET Fe ions.
Figure 1 shows the clonogenic survival curveof normal human lung embryonic ﬁbroblast WI38 cells irradiated with 90 MeV/u Fe ions at
1000 keV/µm.
WI-38 cells were plated in a
25-cm2 cell-culture ﬂask for one week before irradiation in order to form conﬂuent monolayers. Carboxy-PTIO (c-PTIO；(2-(4-Carboxyphenyl)4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide))6) is ascavenger of NO. The c-PTIO solution was diluted before the start of the experiments in order to obtain thedesired culture medium with a ﬁnal c-PTIO concentration of 20 µM 2 h before irradiation. The surviving
fraction was determined by a colony formation assay.
As previously reported,2,3) HRS was observed in thecells irradiated with low doses of Fe ions. The surviving
fractions of the cells that were pretreated with c-PTIO
at doses of over 1 Gy were not signiﬁcantly diﬀerent
from those of the cells that were not pretreated with cPTIO. The decrease in the cell survival at low doses ofunder 1 Gy was partly suppressed by the pretreatment∗1

Central Research Institute of Electric Power Industry

with c-PTIO. These results suggest that NO-mediatedbystander responses are involved in the process of HRS
induced by low doses of Fe ions. The incomplete suppression of the HRS by c-PTIO indicates that othermolecules are involved in bystander signaling. Next,
we will examine the eﬀect of the inhibitor of GJIS andthe scavenger of ROS on the HRS induced by low dosesof high-LET Fe ions.

Fig. 1. Cell-survival curves of WI-38 cells. Conﬂuent
monolayers of WI-38 cells were irradiated with 90
MeV/u Fe ions (1000 keV/µm) and were pretreatedwith c-PTIO with a concentration of 20 µM or not pretreated. The cells were harvested and plated 24 h after
irradiation. Surviving fractions (SFs) were normalized
to those for non-irradiated controls. Panel A shows all
SFs obtained in this study. Panel B shows SFs for doses
under 0.5 Gy. The error bars of the SFs represent thestandard errors of the means (SEMs).

References
1) K. M. Prise et al.: Radiat. Prot. Dosimetry 99, 223(2002).
2) M. Tomita et al.: RIKEN Accel. Prog. Rep. 41, 220(2008).
3) M. Tomita et al.: RIKEN Accel. Prog. Rep. 42, 276(2009).
4) H. Matsumoto et al.: J. Radiat. Res. 50, A67 (2009).
5) M. Tomita et al.: Radiat.Res., in press.
6) T. Akaike et al.: Biochemistry 32, 827 (1993).

- 276 -

RIKEN Accel. Prog. Rep. 43 (2010)

Comparison of mutations of Neurospora crassa DSB
repair-deficient mutants induced by carbon-ion beam
L. Q. Ma,* S. Tanaka,* H. Inoue,* Y. Kazama, K. Nishihara, T. Hirano, T. Abe, and S. Hatakeyama*

Ion beams are known to cause severe damages tovarious cellular components. In particular, exposure
to ion beams can cause DNA double-strand breaks(DSBs). DSBs are generally repaired by either of thefollowing two DSB repair systems: nonhomologous
end-joining (NHEJ) or homologous recombination(HR).
If DSBs are allowed to persist or are
improperly repaired, mutations will occur. In thisstudy, we determined the types of mutations inducedin carbon-ion irradiated wild-type strains and DSB
repair-deficient mutant strains.
A carbon-ion beam (12C6+; energy: 135
MeV/u, LET: 30 keV/µ m) was used to irradiate theconidia of the filamentous fungus Neurospora crassa
at a dose of 25 to 200 Gy. For our experiments, weused the mus-52 (YKU80 homologue, NHEJ deficient)and mei-3 (RAD51 homologue, HR deficient) mutant
strains, as well as 74OR-28a, which was a wild-type
control strain. The forward-mutation frequency wasdetermined by calculating the occurrence of genetic
alteration at the ad-3 loci (ad-3A or ad-3B), whichcauses the accumulation of a purple metabolic
intermediate of the adenine biochemical pathway andthus results in purple colonies. At a dose of 100 Gy,
the mutation frequency of the mus-52 strain wasapproximately 2.8 times lower than that of thewild-type strain (3.3 x 10-5/conidia). Conversely, thefrequency of mutation of the mei-3 strain was about
3.0 times that of the wild-type.
Single colony isolates obtained from purple
colonies arising in jug cultures were subjected togenetic complementation tests to determine whether
mutations had been introduced in ad-3A (924 bp) or
ad-3B (2501 bp) genes. Sequence analysis of DNA
fragments obtained by PCR amplification of the ad-3A(or ad-3B) gene from genomic DNA isolated fromeach mutant was then carried out. The types ofmutations observed in the ad-3A and ad-3B genes ofeach strain are shown in Fig. 1 and Fig. 2, respectively.
In three independent experiments using the mus-52
mutant, we observed no mutations in the ad-3A gene
and a total of 16 mutations in the ad-3B gene; thisindicates that mus-52 has a relatively low mutation
frequency. It was observed that deletions were themost common type of mutation in the wild-type strain
and in mei-3, while transversions were predominant inmus-52.
According to the mutational analysis performed by
Y. Matuo, single base substitutions, especially GC
TA transversions, are most commonly induced by the
carbon-ion
beam
irradiationofwild-type
Saccharomyces cerevisiae (Y. Matuo et al., Mutat.

Res. 2006, 602: 7-13). This is similar to the trendthat was observed in the mus-52 mutant of N. crassa,
which is deficient in NHEJ and therefore, must use
HR. Since S. cerevisiae has an extremely highfrequency of HR compared to other eukaryoticorganisms, one could speculate that in cells where HR
is highly active, single base substitutions are more
likely to occur. Additionally, as is the case in N.
crassa, the occurrence of HR is also low in plants, andthus, it is possible that mutational analyses conducted
for N. crassa can also be used in plant-breedingstudies that involve ion-beam irradiation.
We could not determine whether the mutation
occurred in the ad-3A or the ad-3B gene in some of
the ad-3 mutants generated in this study. It is
possible that in addition to the ad-3 mutation, thesestrains are deficient in an essential gene. In this case,we suspect that some of these strains carry a large
deletion mutation that removes ad-3A and/or ad-3B as
well as a neighboring essential gene. To confirm thishypothesis, we are developing tester strains that may
help us identify such large deletions.
*Laboratory of Genetics, Saitama University- 277 -

RIKEN Accel. Prog. Rep. 43 (2010).

Chronic effects of ion-beam irradiation on protonemal cells in the moss

Funaria hygrometrica

Growth rate (%)

100

C
Ne
Fe
Ar

75
50
25
0
0

200

Fig. 1. Changes in growth
rates of protonemal cells at
10 days after inoculation.
Bars show standard error(n=30). Arrows show a pointwith strong induction of andleafy
gametophytes
development.

400

Dose (Gy)

RIKEN, Plant Science Center＊2
DOWA ECO-SYSTEM CO., LTD., Environmental Protection Lab.
＊1

(a)

Ｃ
Ｎｅ
Ｆｅ
Ar

30
20
10

6
Length of shoot (mm)

40

C
Ne
Fe
Ar

4

(b)

2

0

0
0

200

400

0

Dose (Gy)1020

Numbe r of leaf

Fig. 2. Chronic effects of heavy-ion irradiation on leafy
gametophytes development form protonemal cells. (a) Dose
response changes in mean number of leafy gametophytes
per colony at 24 days after inoculation. Bars show standard
deviation (n=30). (b) Relationship between leaf number andshoot length at 40 days. Bars show standard error (n=30).

150Gy

25Gy

100Gy

100Gy 150Gy
50Gy

50Gy

25Gy

12.5Gy12.5Gycontrol

control

Ash-tolerance moss Funaria hygrometrica Hedw. grows
on waste area (e.g. final landfill, smelter) in field. It alsoprefers burned areas or campfire sites, where the fire has
released large amounts of nutrients. In our previous works,
we obtained the cultured cells from the plant growing on awaste area (Omuta city, Fukuoka Pref., Japan) and we
demonstrated that the Funaria cells have very large
capacities with an adsorption of lead from water1). We are
now developing on the bio-sorption systems of watercontaminated with heavy- and/or rare-metals using a novel
mutant cells which created by ion-beam irradiation
technology. In this report, we describe the effects ofion-beam irradiation on protonemal cells in this moss.
Protonemal cells were cultured on agar plate seated withcellophane. Their cells were irradiated by 12C6+(LET 23
keV/μm), 20Ne10+(LET 63 keV/μm), 40Ar17+(LET 280
keV/μm) and 56Fe24+(LET 640 keV/μm) with a dose rangeof 0 to 400Gy. Each ion was accelerated to 135, 135, 95 and90 MeV/nucleon by RRC. Then, their cells were collectedwith cellophane to inoculate on a new agar plate and eachplate was incubated under a same condition for 40 days. We
checked the growth rate of protonemal cells at 10 days after
inoculation and counted the number of leafy gametophytes
per a colony at 24 days after inoculation. Length of shootand number of leaf in 30 samples of leafy gametophytes
were also examined at 40 days after inoculation.
Changes in growth rate were caused by ion-beamirradiation (Fig.1). Leaf gametophytes development was
induced at lower dose irradiation with high growth rate
(Fig.1, 2). For example, Fe-ions obviously induced leafy
gametophytes development (Fig.3). Fe-ion treatment with
150Gy achieved the peak value, suggesting that higher
mutagenic potential may occur at 150Gy (Fig.2, 3).
Similarly, each specific peak value for C, Ne, and Ar was
also observed (i.e. 200-225Gy for C, 200Gy for Ne, 75Gy
for Ar) (Fig.3). These results show that specific peak values

Numbe r of leafy gametophyte / colony

M. Itouga*1, Y. Komatsu-Kato*1, S. Kawakami*2, Y. Kazama, H. Ichida, Y. Hayashi, T. Abe, and H. Sakakibara*1

Fig. 3. Effect of 56Fe ion irradiation on protonemal cells.
Typical colony and leafy gametophytes are shown as opticalimages. Bar = 2.0 mm.
for heavy-ions are our optimum condition for Funaria
mutation breeding, however these chronic effects areassociated to several biological changes by stress responsesuch as accumulation of reactive oxygen species (ROS) to
heavy ion irradiation2).
In our future works, we should confirm these effects are
not depended on transient responses to heavy ions.
References

1) M. Itouga et al. PCT/JP2008/053142.
2) L. Zhang et al.: Nuclear Science and Techniques 19, 138(2008).

- 278 -

RIKEN Accel. Prog. Rep. 43 (2010)

Seed hypoplasia induced by heavy-ion beam irradiation of pollen grains
in dioecious plant Silene latifolia
K. Ishii＊1, W. Aonuma＊1, C. Torii＊1, N. Fujita＊1, Y. Kazama, T. Abe, and S. Kawano＊1
We have previously conducted carbon-ion-beamirradiation of dry seeds of the dioecious plant Silene
latifolia and obtained sex-reversal mutants.1) However, themutant derived from the irradiated seeds exhibited chimericphenotypes. Fixation of the mutant gene was quite difficult.
Therefore, to obtain mutants without chimeric mutations,carbon-ion irradiation of the pollen grains was performed,
and this was followed by artificial pollination. Further, weinvestigated the hypoplasia that was observed in the seeds
derived from pollen grains irradiated with the heavy-ion
beam.
Mature anthers of an inbred line (K line) of S. latifolia
were irradiated with a 12C6+ beam (135 MeV/nucleon) at adose of 0–200 Gy; the LET of the ions was 23 keV/µm. The
ratio of the number of pollen grains that showed pollen-tube
growth without any rupture to the total number of pollen
grains was calculated at 24 h after sowing in thegermination medium (Fig. 1A). In the case of the pollen
grains irradiated at doses of up to 10 Gy, the germination
rate of the pollen grains was 100%. On the other hand, atdoses of over 20 Gy, the number of of pollen grains
showing pollen-tube growth gradually decreased as theabsorbed dose increased.
The irradiated pollen grains were used to fertilize female
plants of the K line. After one month, seeds were collected
and sown in pots. The germination rates were measured
three weeks after sowing (Fig. 1B). The germination rate of
the seeds derived from 5-Gy-irradiated pollen grains was
55% and that of the seeds derived from 60-Gy-irradiatedpollen grains was 0%. The 50% inhibitory dose (I50) for theirradiated seeds and that for the seeds derived from theirradiated pollen grains were approximately 150 Gy and 30
Gy, respectively.
Two types of seeds were derived from the irradiatedpollen grains. Seeds of type A showed normal morphology,
and their short axes were more than 1 mm in length (Fig.
2A). Seeds of type B exhibited aberrant morphology andtheir short axes were less than 1 mm in length (Fig. 2B).
These two types of seeds coexisted in the same capsule. The
ratio of the number of type-A seeds to the total number ofseeds decreased as the absorbed dose increased (Fig. 3A,
black circles). The germination rates of both types of seeds
were measured three weeks after sowing (Fig. 3B). The
germination rate of type-A seeds derived from the
40-Gy-irradiated pollen grains was 81%, while that of thetype-A seeds derived from the 60-Gy-irradiated pollen
grains was 0%. On the other hand, the germination rate of
type-B seeds derived from the pollen grains irradiated atdoses of up to 20 Gy was 17%, while that of the type-B
seeds derived from the 40-Gy-irradiated pollen grains was＊1

Department of Integrated Biosciences, Graduate School of Frontier
Sciences, The University of Tokyo

0%. Thus, we can obtain plants in which abnormality
during embryogenesis would not be observed, by sowing
only type-A seeds.

Fig. 1. Effects of carbon-ion-beam irradiation. (A) Survival
rate of irradiated pollen grains. (B) Germination rate ofseeds derived from the irradiated pollen grains. The relative
rates for 0-Gy-irradiation are defined as a survival rate or agermination rate of 100%.

Fig. 2. Seeds obtained from irradiated pollen grains. (A)Type-A seeds. (B) Type-B seeds. Bars = 1 mm.

Fig. 3. Difference between the two types of seeds. (A)Ratios of the number of type-A seeds (black circles) and thenumber of type-B seeds (white circles) to the total numberof seeds in each capsule. (B) Germination rates of type-A(white bars) and type-B (gray bars) seeds. The relative rate
for 0-Gy irradiation is defined as a germination rate of100%.
References- 279 -

1) K. Ishii et al.: RIKEN Accel. Prog. Rep. 41, 226 (2008).

RIKEN Accel. Prog. Rep. 43 (2010)- 280 -

 RIKEN Accel. Prog. Rep. 43 (2010)
Characterizatio n of te mperatur e-sensitive chloro tic mutant
induced by ion beam irradiatio n
M. Nakagawa, H. Takehisa,1 Y. Hayashi, H. Tokairin, T. Sato,2 and T. Abe

Mutants have a very important role in the breeding anddevelopment of new cultivars. Heavy-ion beam irradiation
is an effective technique used in mutation breeding to
produce new cultivars. Rice is an important staple food anda model monocot plant, especially among cereal species. To
evaluate the effect of heavy-ion beam irradiation on
mutation induction in rice (Oryza sativa L. cv. Nipponbare),we have examined the frequency of chlorophyll-deficientmutants. Line 22-4Y was one of the chlorotic mutants withsemi-dwarf phenptype isolated from M2 populations thatwere irradiated with a C-ion beam (LET:22.5 keV/mm; 20
Gy).1) In the early seedling stages, the 22-4Y mutant plants
produced chrolotic leaves only the first four leaves andduring the later stages in a paddy field, the plant produced
mostly gren leaves. In addition, when the 22-4Y plants weregrown at 25℃, chlorophyll deficiency was observed, but
the plants produced green leaves when grown at 30℃.
These plants exhibiting conditional chlorosis are called“virescent.” The previously reported virescent rice mutants,
virescent-1, virescent-2, and virescent-3, also have thetemperature-dependent chrolosis phenotype. 2)
To characterize the temperature-dependent chlorosis
phenotype, we analyzed temperature-shift experiments. In
the experiment with a temperature shift from the restrictive
temperature (25℃) to the permissive temperature (30℃)
after imbibition in darkness for four days, the 22-4Y plants
were almost green, and chlorophyll deficiency wasobserved only on the toward edge of the second leaf, which
had emerged before the temperature shift. In the experimentwith a temperature shift from 30℃ to 25℃, the 22-4Y
produced chlorotic leaves, no chlorosis was obserbed onedge of the blade and sheath of the second leaf. These
results indicate that the virescent phenotype of 22-4Y isirreversibly determined by the temperature at thedevelopmental stage of the leaf.

Fig. 1. Comparison of the phenotype of 22-4Y plants grownunder different temperature conditions five days after
germination.
1
2

NIAS, Genome Resource Center
Graduate School of Life Science, Tohoku University

To determine the number of genes controlling chlorosis
in 22-4Y, F2 plants that were obtained by crossing the
22-4Y and wild-type strains were subjected to genetic
analysis. Seventy mutants and 295 wild-type individuals in
the F2 populations had a segregation ratio of 3:1 ((χ2 =0.01 ) < (χ20.05 = 3.84)). From the results of the genetic
analysis, it was inferred that 22-4Y was a single recessive
mutant.
Genetic mapping of the mutation locus of 22-4Y was
performed using F2 plants that were obtained by crossing
22-4Y mutant (var. japonica) and Kasalath (var. indica).
Using 36 STS markers and 4 CAPS markers, the 22-4Y
locus was located between 75 cM and 80.4 cM on
chromosome 5. Furthermore, thirteen SSR markers wereselected to generate a fine physical map. 22-4Y wasmapped within the 422-kb region between the STS marker
E10886 and the SSR marker RM18690 on the long arm ofchromosome 5 (Fig. 2).
A classical phenotypic marker, virescent-10, has been
mapped previously in this region, but the gene responsible
for the virescent phenotype has not been isolated. 2) Wesuggest that the mutation in 22-4Y is caused by the samegenes that cause mutation in virescent-10.

Fig. 2. Genetic mapping of 22-4Y on chromosome 5.
The figure on the left shows the genetic linkage map whilethat on the right shows the physical map. The black box
indicates the candidate region for the 22-4Y locus.
References
1) Y. Hayashi, et al.: Proc. 18th Int. Conf. Cyclotrons andTheir Applications (Cyclotrons 2007), 2008, p.#237.
2) A. Yoshimura et al.: Plant Mol. Biol. 35, 49 (1997).

- 281 -

RIKEN Accel. Prog. Rep. 43 (2010)

Identification of mutated gene induced by heavy ion beam irradiation in rice
Y. Hayashi, H. Takehisa＊1, Y. Kazama, S. Ohbu, N. Fukunishi, H. Tokairin, T. Sato＊2, and T. Abe
Heavy-ion beams have been recognized as an effective
mutagen. We have investigated the effect of heavy-ion
beam irradiation on mutation induction in rice. The higheffectiveness of ion-beams was indicated by the highfrequency of chlorophyll-deficient mutants in M2
progenies with low dose of irradiation1). This is one of
the characteristic features of mutation induction by
heavy-ion beam irradiation. Accelerated particles of ionswith high linear energy transfer (LET) are thought to becapable of causing local DNA damage. As a result, it ispossible to obtain mutants without involving undesirable
characters. In previous studies, we isolated various
mutants such as dwarf, salt tolerant, necrosis, bronzing
and staygreen (Table 1). Most of these mutants were
fixed in the M2 or M3 generation, and this is anotherfeature of mutation induction by heavy-ion beamirradiation. Furthermore, it is possible to clarify thecharacteristics of mutation induced by heavy-ion beams
by identifying the mutation sites of these mutants. In thispaper, we report the identification of the mutated regionof a dwarf mutant induced by heavy-ion beam irradiationin rice.
We obtained the dwarf mutant (6-66) by irradiating
imbibed seeds of rice (Oryza sa tiva L. cv. Nipponbare)with Ne-ion beam (15 Gy, 63 keV/μm). 6-66 showed thetypical phenotype of rice gibberellin (GA) related
mutants, severe dwarf with wide leaf blades and darkgreen leaves (Fig.1). In addition, 6-66 showed no
response to GA3 treatment. In the GA signaling pathway,
GID1 is a receptor for GA2) and GID2 is a positive
regulator of GA3). Both these proteins are necessary for
GA action. PCR analyses of mutant and wild type were
performed using specific primers to GI D1 and GID2
genes. Sequence analysis revealed that 6-66 contained
4-bps deletion in GID2, which caused flameshift
mutation (Fig.2). No mutation was detected in GID1.
It is necessary to detect more mutated regions of ricemutants and characterize the mutations induced byheavy-ion beam irradiation. Furthermore, detection of

mutated genes may lead to the discovery of unknown
genes or new functions of known genes in rice. Analysesof mutations in some other mutants of rice shown in
Table1 are in progress.
Table 1.

Isolated mutants by heavy-ion beam irradiation

Line

Ion

6-99L
19-74
7-3B
11-29
22-70
40-S
22-4Y
11-26
5-106
3-58
6-66

C
C
Ne
C
C
C
C
C
C
C
Ne

A

Dose

LET

(Gy)

(keV/μm)

40
20
10
20
20
40
20
20
20
15
15

23
23
63
23
60
23
23
23
30
50
63

Phenotype
Salt tolerant
Salt tolerant
Bronzing
Bronzing
Necrosis
Crinkled dwarf
Chlorosis
Staygreen
Waxy
Semi-dwarf
Dwarf

B

Fig. 1. Gross morphology of 6-66
plants.
(A) Five-weeks-old seedlings.
(B) Higher magnification of a6-66 plant. Bar=5cm.
Reference
1) Y. Hayashi et al.: RIKEN Accel. Prog. Rep. 42, 285(2009).
2) M. Ueguchi-Tanaka et al.: Nature 437, 693 (2005).
3) A. Sakai et al.: Science 299, 1896 (2003).

Fig. 2. Comparison of amino acidsequences of GID2 between wild
type and dwarf mutant (6-66). The
GID2 gene consists of one exon.
Identical amino acids are represented
by white-on-black letters.

*1 National Institute of Agrobiological Sciences*2 Graduate School of Life Sciences, Tohoku University- 282 -

RIKEN Accel. Prog. Rep. 43 (2010)

Identification of heavy-ion-beam induced DNA mutation by genetic mappingin Arabidopsis mutant
Y. Kazama, S. Ohbu, Y. Hayashi and T. Abe
Heavy-ion-beam irradiation can efficiently induce
mutations. We are studying the type of mutation induced byheavy-ion beam irradiation. Previously, we had reported a
985-bp deletion in an Arabidopsis mutant and a deletion of
more than 3 kb in a tobacco mutant, both of which werecaused by 12C6+-ion irradiation.1), 2) In this study, we
determined two mutations occurring in Arabidopsis mutants
to gain further insight into mutations induced by heavy-ion
beam.
Two mutants, C-48-as1 and Ar-28-pg1, were isolated byscreening the M2 generation obtained by irradiation of
wild-type dry seeds (col-0) with 12C6+ ions (250 Gy, 22.5
keV/μm) and 40Ar17+ ions (50 Gy, 290 keV/μm),
respectively. Phenotypes of these mutants are shown in Fig.
1. Ar-28-pg1 developed yellow-green leaves (Fig. 1). In amature Ar-28-pg1 plant, a strong chlorosis was observed in
the leaves (data not shown). C-48-as1 showed increased
leaf growth and an altered pattern of leaf emergence (Fig. 1).
The number of leaves observed in C-48-as1 20 days aftersowing was about twice that in the wild-type plant. Pollens
from these mutants were used to pollinate a wild-type(col-0). All of their progenies showed wild-type like leaves,indicating that both mutants have a recessive mutation.
The method for identifying the responsible mutation ineach mutant is summarized in Table 1. To determine theresponsible loci of the mutants, genetic mapping was
carried out as described previously.3) A total of 151 and 114
homozygous F2 plants were used for mapping of C-48-as1
and Ar-28-pg1, respectively. Rough mapping results
showed that the responsible loci of the C-48-as1 andAr-28-pg1 mutants are located in a 2.6-Mb region near thetelomere of chromosome 3 and a 3-Mb region near thecentromere of chromosome 5.
From the results of phenotype analysis and genetic
mapping, their responsible genes were predicted. Databasesearch (TAIR, http://www.arabidopsis.org/) indicated thatthe putative responsible genes for C-48-as1 and Ar-28-pg1
were ALTERD MERISTEM PROGRAM (AMP) 1 andETHYLENE-DEPENDENT GRAVITROPISM-DEFICIENT
AND YELLOW-GREEN (EGY) 1, respectively.4),5) AMP1
encodes a putative glutamate carboxypeptase,

Fig. 1 Phenotypes of isolated mutants. Bars = 2 mm.
passively involved in peptide signaling.6) EGY1 encodes a
Genomic
membrane-associatedmetalloprotease.4)
fragments containing AMP1 and EGY1 in C-48-as1 andAr-28-pg1, respectively, were sequenced. In C-48-as1, a
single A-to-T transversion at 2384-bp downstream of theinitiation codon was observed in AMP1. This basesubstitution caused a stop codon resulting in the productionof 3’-truncated protein. In Ar-28-pg1, a 5-bp deletion (fromnucleotide 1410-1414) with five base substitutions (onetransition and four transversions) was observed in EGY1.
The 5-bp deletion created a frameshift. It was observed thatthe phenotypes of C-48-as1 and Ar-28-pg1 are quite similar
to those of the original null mutants, respectively, indicatingthat both mutants might be null.
Accumulating of these mutation data will help us
understand the characteristics of heavy-ion-induced
mutation.
References

1) Y. Kazama et al.: Bioci. Biotech. Biochem. 71, 2864 (2007).
2) Y. Kazama et al.: RIKEN Accel. Prog. Rep. 42, 280 (2009).
3) G. Jander et al.: Plant Physiol. 129, 440 (2002).
4) G. Chen et al.: Plant J. 41, 364 (2005).
5) A. Chaudhury et al.: Plant J. 4, 907 (1993).
6) C.A. Helliwell et al.: Plant Cell 13, 2115 (2001).

Table 1 Summary of detection of mutation by genetic mapping
Analysis

Genetic mapping

technique

Database

Sequencing

searchChromosome

RegionGene

Mutation typeC-48-as1

3

2.6 Mb near telomere

AMP1

BS

Ar-28-pg1

5

3.0 Mb near centromere

EGY1

Del (5 bp) + BS

BS: Base substitution, Del: Deletion- 283 -

RIKEN Accel. Prog. Rep. 43 (2010)

LET-dependent effect of heavy-ion-beam mutagenesis on deletion size
Y. Kazama, T. Hirano, Y. Liu,＊1 K. Nishihara, S. Ohbu, Y. Hayashi and T. Abe
A heavy-ion beam is a high-Linear Energy Transfer (LET)
radiation compared with X-ray and γ-ray. Previously, we
have reported that LET affects the mutation rate and that an
LET of 30 keV/μm is most effective in inducing mutation in
dry seeds of Arabisopsis thaliana.1) Thus, LET isconsidered to important factor for mutation induction by
heavy-ion beam. In Mesorhizobium loti, irradiation by iron
ions (640 keV/m) induced lager deletions compared tothose induced by carbon ions (23 keV/m).2) From thisresult, we postulate that LET may also influence thedeletion size in the mutated genes. To date, there is no
known mutagen that can control the deletion size. In thepresent study, therefore, we aimed to develop a novel
method for deletion-size-controlled mutagenesis byheavy-ion-beam irradiation with different LETs. As the firststep toward controlling deletion size, we irradiated theseeds of A. thaliana with heavy-ion beams having four
different LETs ranging from 30.0 to 640 keV/μm andanalyzed the deletion size in mutated genes.
Dry seeds of A. thaliana (Col-0) were packed in a plastic
bag to obtain a monolayer of seeds. They were irradiatedwith 12C6+ (22.5 keV/μm, 30 keV/μm, or 290 keV/μm),
40
Ar17+(290 keV/μm), or 56Fe24+ (640 keV/μm) ions using
the E5 beam line at the RIBF. These ions were accelerated
up to 1.62, 3.80, and 5.04 GeV. The LET of 12C6+ werevaried by passing the ions through a combination ofabsorbers. The irradiation doses were selected on the basisof the results of previous research.1) The irradiated M1 seeds
were surface-sterilized and incubated on a 0.7%
agar-containing MS medium supplemented with MS
vitamins and 3% sucrose at 4°C in the dark for four days toinduce vernalization. Then, they were grown at 22°C underlong-day condition (16 h light and 8 h of darkness).
Seedlings that developed true leaves were transplanted onplastic trays (13 × 9 cm) containing soil. Eleven seedlings
were planted in each tray and cultured at 22°C underlong-day condition in a greenhouse. M2 seeds werecollected from each tray and they were considered as one
batch. From the M 2 generation, elongated hypocotyl (hy)and globrous (gl) mutants, were screened by growing theM2 seeds on an MS agar medium. DNAs of the collectedmutants were purified using DNeasy plant mini kit(QIAGEN). Then, they were subjected to PCR andsequencing by using specific primers for the putative
responsible genes (HY1, HY2, HY3, and HY4 for the hymutants; GL1, GL2, and TTG1 for the gl mutants). M3 seedsof the mutants were harvested and the phenotype of the M3
plants was analyzed to confirm whether the phenotype ofthe mutants was inherited.
In total, 89,794 of M2 plants were screened, and 36＊

1

Institute of Modern Physics, Chinese Academy of Sciencemutants were collected (Table 1). The highest mutation rate
was observed 30-keV/μm irradiation; this observation was
in agreement with a previous result according to which the
30-keV/μm irradiation is most effective in inducing albino
mutants.1) Since the mutants isolated from the same batch
were considered to have originated from the same M1 plants,
mutants of the same batch that exhibited the same
phenotype were characterized as a single mutation event.
After determining the DNA mutation, all of the mutantsfrom the same having the same phenotype were analyzed by
PCR and sequencing.
Twenty-one mutations were identified in the genes of themutants (Table 2). The mutations included fifteen deletions,
two translocations with a deletion, two base substitutions,
one insertion, and one translocation. This result indicatesthat the heavy-ion-beam irradiation predominantly induces
deletion mutation. Base substitution was observed only inthe case of 22.5-keV/μm irradiation. When the sizes of thedeletions induced by radiations with different LETs werecompared, smaller deletions were observed in the case oflower-LET irradiation. In contrast, with 290-and
640-keV/μm irradiations, large deletions of over 1,000 bp
were detected.
Table 1. Screening results for hy and gl mutants.
LET(keV/m)Ion
speciesDose(Gy)

No. of
M1

No. of
M2

12 6+
122.5
C
250
2,024 11,662
12 6+
122.5
C
450
1,710 16,103
12 6+
130.0
C
400
1,419 13,485
12 6+
290.0
C
50
1,452 15,140
40
17+
290.0
Ar
50
1,100 17,229
56
640.0
Fe24+
50
2,893 26,175*Total number of isolated hy and gl mutants.

No. ofmutants*
15
17
14
11
14
15

Table 2. Classification of mutations induced by heavy-ion
beams with different LETs.
Deletion
LET
Base
10
1000 1000 Others(keV/m) substitution
bp≧ bp≧
bp<
122.5
2
3
2
0
0
130.0
0
4
1
0
1
290.0
0
1
2
1
0
640.0
0
1
0
2
1
References

1) Y. Kazama et al.: Plant Biotech. 25, 115 (2008).
2) H. Ichida et al.: Mutation Res. 639, 101 (2008).

- 284 -

RIKEN Accel. Prog. Rep. 43 (2010).

C-ion-induced DNA mutations in variegated mutant Arabidopsis
K. Nishihara, Y. Kazama, M. Nakagawa, T. Hirano, S. Ohbu, S. Kawano,* and T. Abe

Since high Linear-Energy-Transfer (LET) heavy-ion
beams effectively induce DNA double-strand-breaks1), they
induce high-frequency mutations. LET affects mutation rate
when dry Arabidopsis seeds are irradiated with heavy-ion
beams2). To study LET-dependency of DNA mutations, westudied DNA mutations induced by irradiation withheavy-ion beams. We report two DNA mutations inducedby C-ion irradiation with LET of 50 keV/µm in Arabidopsis
thaliana.
We focused on variegated mutants, some of which were
well characterized, and identified the genes that had
mutations causing the variegated phenotype. The var1
(yellow variegated 1) mutant had normal cotyledons andgreen- and white-sectored rosette leaves3). The var2 mutant
had normal cotyledons and white/yellow sectors in thenormally green parts of the plant3). The var3 mutant hadgreen cotyledons and yellow variegated rosette leaves4). The
cotyledons of the immutans (im) mutant appeared white
under high-intensity light, and im had green- andwhite-sectored leaves5). The thylakoid formation 1 (thf1)
mutant had plastids in the white/yellow sectors, the plastids
were composed of accumulated vesicles and lackedorganized lamellar structures6). DNA mutations weredetected by screening variegated mutants and sequencing
the genes responsible for the mutations.
Dry Arabidopsis seeds were irradiated with C-ions (135
MeV/nucleon) at a dose of 200 Gy with LET of 50 keV/µm.
The irradiated M1 seeds were incubated on 1/2 Murashige
and Skoog agar medium for 3 days at 4°C in the dark forvernalization and then at 23°C under 16-h light/8-h dark
conditions for germination. Three weeks after germination,
484 well-grown plants were selected for transplantation into
pots. Eleven seedlings were transplanted into each pot. M2
seeds were collected from 476 M1 plants. Thirteen days
after germination, the variegated mutants were screened
from among 19,124 M2 seedlings.
We found three variegated mutants (C-11-var1,
C-11-var2, and C-35-var1) (Fig. 1). Among them,WT

C-11-var1

C-35-var1

C-11-var1 and C-11-var2 were obtained from the same pot.
The phenotypes of C-11-var1 and C-35-var1 were similar to
those of im and var2 mutants, respectively. However, we
could not determine the genes responsible for these
phenotypes only by phenotypic characterization. Therefore,
we sequenced all genes in these mutants (Table 1).
Sequencing analysis revealed that the C-11-var1 mutant
had a 2-bp deletion in the IM gene sequence (Fig. 2). The
deletion was located in the first exon of the IM gene, andcaused a frameshift mutation. Sequencing of the IM gene in
the C-11-var2 mutant revealed that this mutant had the same
deletion as C-11-var1, thereby indicating that these twomutants may have originated from a single M1 plant. The
C-35-var1 mutant had a 46-bp deletion in the VAR2 gene(Fig. 2). This deletion occurred at the last 4 bp of the firstexon and the first 42 bp of the following intron. Therefore,
this deletion may have caused a shift in the splice site.
Gathering data on mutations induced by C-ion irradiation
will help us to understand the mutagenesis ability of C-ion
irradiation.
Table 1. Sequencing results for genes responsible formutations in variegated mutants
Gene name
VAR1
VAR2
VAR3
IM
THF1

Fig. 1. Photographs of variegated Arabidopsis thaliana with
mutations induced by C-ion irradiation with LET of 50
keV/µm. Bar = 1 cm.
Graduate School of Frontier Sciences, The University of Tokyo.

C-35-var1
No mutation
46-bp deletion
No mutation-

Fig. 2. Deletions detected in variegated mutants. The
numbers indicate the nucleotide position from the initiation
codon.
References＊

C-11-var1
No mutation
No mutation
No mutation
2-bp deletion
No mutation

1) D. T. Goodhead: Int. J. Radiat. Biol. 65, 7 (1994).
2) Y. Kazama et al.: Plant Biotech. 25, 113 (2008).
3) J. M. Martínez-Zapater et al.: J. Hered. 84, 138 (1993).
4) H. Næsted et al.: J. Cell Sci. 117, 4807 (2004).
5) C. M. Wetzel et al.: Plant J. 6, 161 (1994).
6) Q. Wang et al.: Plant Physiol. 136, 3594 (2004).

- 285 -

RIKEN Accel. Prog. Rep. 43 (2010).

Early-flowering mutants developed by heavy-ion-beam irradiation in soybean
H. Kuribara＊1, Y. Sadamura＊1, H. Watanuki＊1, T. Hirano, Y. Hayashi, T. Abe

The soybean cultivar ‘Oojirodaizu’ is known as a local foodthat tastes good; it is cultivated in Katashina-mura, Gunma
prefecture. In order to increase the demand for‘Oojirodaizu’, its use as green soybean has been proposed.
However, the flowering time of ‘Oojirodaizu’ is too late toproduce green soybean during summer in order to increasedemand. Therefore, in the present study, we attempted todevelop early-flowering mutants by heavy-ion-beamirradiation in ‘Oojirodaizu’, as a step toward efficient usageof local germplasm.
Seeds of soybean (Glycine max (L.) Merr. ‘Oojirodaizu’)
were irradiated with a C-ion beam (22.5 keV/μm) at doses
between 10 and 200 Gy. The irradiated seeds were sowed in
the field for raising seedlings, and then, their germinationand survival rates were measured. The seedlings thatsurvived were transplanted to the field, and a yield survey
was carried out. For screening of the early-floweringmutants in the M2 generation, the flowering time and seed
pod maturity were measured from July to August and in
October, respectively. Then, progeny tests were performedin each line of early-flowering mutants.
The germination rate of M1 seeds did not decrease
relative to that of the untreated control (0 Gy), irrespectiveof the dose range (Fig. 1). In contrast, the survival rate of
the seeds decreased from 92% at 100 Gy to 10% at 200 Gy.
The results of the yield survey showed a similar trend in thesurvival rate, and the total number and weight of seeds perplant started to decrease at 100 Gy. These results suggestthat the effective dose for mutant screening is not greaterthan 100 Gy.

When early-flowering mutants were screened from M2plants, we obtained two lines (C-10-47 and C-10-55; Fig. 2)
derived from seeds irradiated at 10 Gy and one line
(C-100-32) derived from seeds irradiated at 100 Gy. In theprogeny test, it was confirmed that the flowering times of
C-10-47 and C-10-55 were about 20 and 15 days earlier
than that of the wild type, respectively. However, the seedyields of the two lines were lower than that of the wild type,
and C-10-47 showed a marked decrease in the seed yield(Table 1). Therefore, it is thought that the mutant line of
C-10-55, which did not show a severe decrease in seedyield, can be used as a breeding parent.

Fig. 2 Phenotype of early-flowering mutant developed byirradiation with a C-ion beam. Photographs were taken on
the same date (August 26th) for the wild type (a) and themutant line of C-10-47 (b).
Table 1 Comparison of seed yield in early-floweringmutants.
Line

Fig. 1 Germination and survival of soybean seeds rate
after irradiation with a C-ion beam. These data wereobtained in a single experiment.
＊1

Number of

Number ofSingle-seed

seed pods

seeds

weight (g)Wild type

99.8

159.7

0.38

C-10-47

6.0

9.0

0.33

C-10-55

53.0

93.0

0.38

These data are the values averaged over the values for
all plants.

Gunma Pref., Seta-Norin High school.

- 286 -

RIKEN Accel. Prog. Rep. 43 (2010)

Induction of high-formaldehyde-absorption mutant by heavy-ion-beamirradiation in Murraya paniculata
T. Hirano, R. Mukai＊1, S. Yoshida, Y. Hayashi, T. Abe
Phytoremediation, or the use of plants for removing
pollutants, is an attractive method for the control of air,water, and soil pollution; this is because this method is
inexpensive and environment friendly. Formaldehyde is oneof the volatile toxic substances that cause the sick house
syndrome and is a suspected carcinogen. The aim of thisstudy is to develop an ornamental foliage plant with novel
functions.
We
attempted
toenhancetheformaldehyde-absorption ability of Orange jasmine(Murraya paniculata), which is an ornamental shrub with
dense foliage and fragrant flowers, by heavy-ion-beamirradiation.
The linear energy transfer of the C ion beam used in thisstudy was 22.5 keV/μm. Dry and imbibed seeds of M.
paniculata were irradiated with the C ion beam at a dose of
10–40 Gy and 5–30 Gy, respectively. The survival rate of
the M1 plants obtained from the irradiated dry seeds did notdecrease, irrespective of the used dose range. On the other
hand, in the case of the plants obtained from the irradiatedimbibed seeds, the survival rate decreased from 78% to
49% when the irradiation dose was increased from 5 Gy to
10 Gy. We also used cuttings for mutation induction; thecuttings were irradiated by a C ion beam at a dose of 5–100
Gy. The survival rate of the axillary buds in the irradiatedcuttings decreased drastically from 85% to 33% when thedose was increased from 50 Gy to 60 Gy.
The mutation rate in the M2 generation derived from theirradiated seeds was calculated on the basis ofmorphological mutations such as leaf variegation, leaf
serration, flower shape mutation, and weeping. The highest
mutation rate was 1.7% in dry seeds irradiated at 30 Gy and9.4% in the imbibed seeds irradiated at 10 Gy. In theregenerated plants obtained from the irradiated axillarybuds, the mutation rate was high (5.1–6.7%) when the dose
was varied between 40 Gy and 50 Gy.
We analyzed the formaldehyde-absorption ability of theM2 plants derived from irradiated seeds and that of theplants regenerated from irradiated the axillary buds. The
experiments were carried out in a 210-L chamber. After
placing the plant in the chamber, 5 μl of 4% formaldehyde
solution was injected into the filter in the fan unit andevaporated in the chamber. After the plants were exposed toformaldehyde for 30 min, the concentration offormaldehyde in the chamber (C: ppm) and the temperaturein the chamber (t: ºC) were measured. Then, the total leaf
area (S: dm2) of each plant used in the experiment was alsomeasured. The residual volume of formaldehyde in the*1

Environmental Affairs Dept., Tokyo Gas

chamber (Q: μg) is calculated by using eq. (1). The velocity
of formaldehyde absorption per unit leaf area (V: μg/dm2/h)
is calculated using eq. (2), and it is assumed that the entire
amount of injected formaldehyde is evaporated in thechamber.
Q=V=

7.68×104×C(1)

273.15＋t
2×(200－Q)(2)

S

For the wild type, the average and maximum values of V
were 31.5 and 97.0 μg/dm2/h, respectively (Table 1). The
maximum value obtained for the wild type was used as thecriterion value for the screening of high-ability mutants.
The plants derived from the irradiated materials werescreened; 58 plants were selected as candidates withenhanced formaldehyde-absorbing ability (Table 1). The
highest value of V was 183.0 μg/dm2/h for the plants
obtained from the irradiated imbibed seeds and 237.0
μg/dm2/h for the plants obtained from the irradiated axillarybuds; the ability of the candidates was 1.9 –2.4 times higher
than the criterion value. These results demonstrate that
mutation breeding by heavy-ion-beam irradiation is apromising method for the development of suitable plantsthat can used in phytoremediation.
Table 1 Evaluation of velocity of formaldehyde absorptionin M2 plants derived from irradiated seeds and plants
derived from axillary buds after ion beam irradiation.
Max value
No. ofIrradiated Dose
No. ofof V
mutantmaterial(Gy)plants(μg/dm2/h) candidates*
Wild type

0

236

97.0

-

Dry seed

30

160

139.0

23

Imbibed
seed

5
10

80
49

131.4
183.0

12
5

Axillary
bud

30
40
50

25
74
45

237.0
131.0
136.5

5
6
7

*Mutants showed V values of more than 97.0 μg/dm2/h.

- 287 -

RIKEN Accel. Prog. Rep. 43 (2010)

Development of early-flowering mutant ofstrawberry cultivar "Satsumaotome" by C-ion irradiation
Y. Takenoshita,* T. Nagatani,* M. Ooe,* H. Saito and T. Abe
In Japan, the demand for strawberries increases at the endof the year. Although the strawberry cultivar"Satsumaotome" developed in Kagoshima prefecture islarge and has fruits of good quality, it is classified as alate-harvesting cultivar and is not suitable for harvesting inseasons during which prices are high. Therefore, we aimed
to develop early-flowering mutants derived from
"Satsumaotome" by ion beam breeding. We estimatedsuitable doses of C-ion beams for irradiation of multiple
shoot cultures1), and we selected an early-flowering mutant
line B05182). In this study, we found genetic uniformity andstability in early-flowering characteristics of B0518, and we
also found that the quality of B0518 is as good as that of theoriginal cultivar.
To examine the uniformity and stability of the earlyflowering, we formed seven lines (B0518-1to7) by clone
propagation from seven individual stocks, which were
propagated from the original B0518 stock. Each line wasplanted in a plastic greenhouse on September 26, 2008, andthe cultivation was carried out by using the standard method
for "Satsumaotome" in Kagoshima prefecture.
The date of flower bud initiation of B0518 was eight days
earlier than that of "Satsumaotome" (Table 1). Because
strawberries were planted in the field just after the flower
bud initiation, this result shows that B0518 can be planted
and harvested than "Satsumaotome". The terminal
inflorescence of B0518 flowered on November 2 andNovember 3, and the primary axillary inflorescenceflowered from Decemmber 24 to 29 (Table 1). The range offlowering dates of the seven lines was very small. The
harvest date of the terminal inflorescence of B0518 was
December 1 which is 14 days earlier than that of"Satsumaotome" (Table 1). On the basis oh these results,
we concluded that there is genetic uniformity and stability
in the early-flowering of B0518.
In terms of the shape of the fruit, color of the peel, andcolor of the flesh, B0518 was identical to "Satsumaotome"(data not shown). These results indicate that the unexpectedchange in fruit quality was negligible in the case of B0518.
As for the harvest until December 31, 2008, the numberof fruits of B0518 was about 2.2 times that of"Satsumaotome", and the fruit yield was about 1.7 times theyield of "Satsumaotome" (Table 2).
From the results of this study, we confirmed that B0518
was a fixed and early-flowering line whose fruits retain the
excellent characteristics of the fruits of "Satsumaotome".
We also confirmed that B0518 was a high-yielding line
compared to the original cultivar "Satsumaotome". We are*planning to further investigate the characteristics of B0518
for commercial production.

Table 1 Flowering and harvest of B0518 in 2008Line
Cultivar
B0518-1
B0518-2
B0518-3
B0518-4
B0518-5
B0518-6
B0518-7
B0518（average）
Satsumaotome

Flowerbud

Terminal
inflorescencePrimary axillary
inflorescence

Initiation
date

Flowering Harvest
date
date
Nov.3
Dec.4
Nov.2
Dec.1
Nov.2
Dec.1
Nov.2
Dec.4
Nov.2
Dec.1
Nov.2
Dec.4
Nov.2
Dec.8
Nov.2
Dec.1
Nov.12
Dec.15

Floweringdate
Dec.29Dec.25
Dec.24
Dec.28Dec.24
Dec.24
Dec.25
Dec.26
Jan.12

Sep.18Sep.26

Table 2 Total number of fruits and fruit yield for B0518.
The fruits were harvested until December 31, 2008Line
Cultivar

Number of
fruits

Fruit
yield

B0518-1
B0518-2
B0518-3
B0518-4
B0518-5
B0518-6
B0518-7

3,446
3,877
4,156
3,752
4,002
3,573
3,797

(fruits/a)(kg/a)

B0518（average）
Satsumaotome

3,800
1,734

77
46

References

73
80
83
73
80
76
74

1) M.Ooe et al.:RIKEN Accel.Prog.Rep.42, 286 (2009)2) Y.Takenoshita et al.:RIKEN Accel.Prog.Rep.42, 287 (2009)

Kagoshima Biotechnology Institute- 288 -

IV. OPERATION RECORDS

1. Operation of RIBF

RIKEN Accel. Prog. Rep. 43 (2010)

Operations of RIBF ring cyclotrons
M. Kase, N. Fukunishi, E. Ikezawa, T. Nakagawa, H. Okuno, N. Sakamoto, M. Fujimaki, H. Hasebe, Y. Higurashi,
T. Kageyama, M. Kidera, M. Kobayashi-Komiyama, H. Kuboki, K. Kumagai, T. Maie, M. Nagase, J. Ohnishi,
Y. Ohshiro,*1 K. Suda, T. Watanabe, K. Yamada, S. Yokouchi, T. Ohki,* 2 N. Tsukiori,*2 T. Aihara,*2 S. Fukuzawa,*2
M. Hamanaka,*2 S. Ishikawa,*2 K. Kobayashi,*2 Y. Kotaka,*2 R. Koyama,*2 M. Nishimura,*2 T. Nakamura,*2
M. Nishida,*2 K. Oyamada,*2 J. Shibata,*2 M. Tamura,*2 A. Uchiyama,*2 K. Yadomi,*2 H. Yamauchi,*2
A. Goto, O. Kamigaito, and Y. Yano
*1
Center for Nuclear Study, the University of Tokyo*2
SHI Accelerator Service Ltd.
In 2009, the operation of four ring cyclotrons (RRC, fRC,
IRC, and SRC) along with two injectors (AVF and RILAC)
in the RIBF accelerator complex was satisfactory.
Although there are various acceleration modes(corresponding to the combinations of these ring cyclotrons),
the RRC works as the first booster ring cyclotron in every
acceleration mode. The annual operation time of the RRC
reached 5140 h in 2009, which was by 30% more than thatin 2008. The operation statistics of RIBF accelerators are
summarized in Table 1.
In 2009, the range of ion mass in the beam in the RIBF
accelerators extended toward lighter masses; on the otherhands in 2007 and 2008 the heavy ion beams such as 48Ca
and 238U beams were used. In March, the new acceleration
mode of AVF-RRC-SRC was tesed for the first time. In
order to skip the IRC, the recently completed bypass beamline was used. A 14N beam with an energy of 250 MeV/u
was successfully accelerated in the new mode, and it wasused for the commissioning of the SHARAQ (the newly
completed spectrometer that is promoted by CNS, theUniversity of Tokyo).

In April, a polarized deuteron beam with an energy of
250 MeV/u was accelerated in the same acceleration mode.
After each cyclotron was tuned precisely in order to achieve
single turn extractions, the polarized deuteron beam could
be supplied to the experiments for three days. In early
May, a 14N beam with an energy of 250 MeV/u was
accelerated again and used for carrying out the further
performance test on the SHARAQ, a beam optics research,and for a preliminary testing of the Kappa magnet.
Experiments involving the use ofαbeam with an energyof 320 MeV/u were scheduled in autumn. Initially, we
intended to produce this beam in the AVF-RRC-SRC mode
as well by changing the acceleration frequency. However,during the frequency tuning of the SRC amplifiers, we met
with the difficulties in using the new frequency (around 32
MHz) in the SRC, as the result of which a vacuum tube in
the final stage amplifier for one of the SRC resonators(RES1) was damaged. Therefore the other mode of
RILAC-RRC-IRC-SRC was chosen in order to avoid using
this frequency. From October to early November, 320
MeV α beam was accelerated successfully and used for- 289 -

the first SHARAQ experiment after it were converged into a
triton beam in the BigRIPS.
At the end of 2009 between November and December,the campaign of heavy-ion beam time was arranged. 238U
and 48Ca beams with an energy of 345 MeV/u wereaccelerated as well as in 2008.
In order to produce 238U+35 ions, a new superconducting
ECR ion source was used in November 2009, which had
been designed for a new injector (RILAC2) and installed on
the 100kV stage for a test to be performed since summer
2009. The beam from the ECR ion source was accelerated
by a dc voltage of 100 kV and transported to the first cavity
of RILAC via a temporary beam line (MEBT) bypassing
the commonly used RFQ linac. Although the 238U35+ beamat the ion source was much more intense than before, theobtained 238U beam at the exit of SRC was 0.7 pnA at
maximum, being around two times.
The matching
between the ring cyclotrons was probably poor.
In December, the 48Ca beam with 345 MeV/n was
accelerated by using the ordinary 18GHz ECR and the RFQ
linac. Just before the beam tuning, a serious vacuum leak
was detected in the main tuner of the SRC resonator (RES2),and the operation was performed with acceleration without
RES2 and with other three cavities in the SRC. In the final
stage of the beam tuning, there was significant instability inthe extracted beam of the SRC, which was later attributed toa poor connection of high voltage line of the SRC deflector(EDC). The 48Ca beam sent to the BigRIPS was limited toaround several tens of pnA.
About half the RRC operation time was devoted toordinary experiments in the Nishina Building, as listed inTable 2. A total of 1070 h were spent on eight kinds of
RIPS experiments, including those on the development of
ion-trapping technology. The experiments related to the
biological research were so extensive that a total of 113 h
were devoted to them; in these experiments the four kindsof beams, namely, 12C, 14N, 40Ar and 56Fe ions were used,
25 iterations were carried out on a regular basis in the E5
target room. In the E3 target room, the RI productions for
multi-tracer was carried out using an intense 14N-135MeV/nbeam, and the simulation of single event in electronic
devices against irradiation of cosmic ray was performed,
using the low energy Kr beam.
In June and July 2009, during the summer shutdown
period, cooling water leaked into the vacuum chamber of
the SRC, because a water pipe of the beam buffer burst;
the buffer was located at the entrance of thesuperconducting magnet (SBM) in the central region of the
SRC. Since the leakage was not noticed for two months, alarge amount of water estimated at more than 20 tons
flowed into the SRC beam chamber. It took around twomonths to repair the SRC; recovery was performed byreplacing the damaged vacuum components and cleaning
the interior of the vacuum chamber.

- 290 -

RIKEN Accel. Prog. Rep. 43 (2010)

RILAC operation
Eiji Ikezawa, Ohki Tomonori,* Kase Masayuki, Takahide Nakagawa, Naruhiko Sakamoto,
Hiroki Okuno, Nobuhisa Fukunishi, Masaki Fujimaki, Makoto Nagase, Tadashi Kageyama, Shigeru Yokouchi,
Misaki Kobayashi-Komiyama, Masanori Kidera, Yoshihide Higurashi, Tamaki Watanabe, Kazunari Yamada,Takeshi Maie, Hiroo Hasebe, Hironori Kuboki, Kenji Suda, Yutaka Watanabe, Toshimitsu Aihara,*
Hiromoto Yamauchi,* Akito Uchiyama,* Kazuyuki Oyamada,* Masashi Tamura,*
Akira Goto, Osamu Kamigaito, and Yasushige Yano＊SHI Accelerator Service Ltd.

The RIKEN heavy-ion linac (RILAC) has been in steady
operation throughout the reporting period and has supplied
various ion beams in various experiments, in beam
acceleration tests, and in beam commissioning. Somestatistics on the RILAC operation from January 1 to
December 31, 2009 are summarized in Table 1. The total
beam service time of the RILAC accounted for 87.0% of
the operation time of the RILAC. The percentages of thestand-alone RILAC and the injection into the RIKEN Ring
Cyclotron (RRC) were 44.2% and 55.8% of the total beamservice time of the RILAC, respectively.
For the beam commissioning and experiments of the RI
238
U,
Beam
Factory(RIBF),
0.67-MeV/nucleon
136
48
Xe, 2.68-MeV/nucleon Ca, and0.67-MeV/nucleon
2.66-MeV/nucleon 4He ion beams accelerated by the
RILAC were injected into the RRC seven times between
February and December 2009.
For installation, as described below, the regular RILAC
Table 1. Statistics on RILAC operation from January 1 to
December 31, 2009.

Operation time of RILAC
Mechanical trouble

4152.0 h
63.0 hStand-alone RILAC
Injection into RRC
Total beam service time of RILAC

1596.5 h2017.5 h3614.0 h

operation was put on hold between March 12 and March 27,
2009, and between April 13 and June 5, 2009.
The beam time schedule was affected by problems in thewater-cooling circuit of an electrical motor and of a valve,as described below. Other machine troubles did not affectthe beam time schedule significantly.
Table 2 summarizes the beam service time of thestand-alone RILAC allotted to each beam course in the
RILAC target rooms in 2009. The e3 beam course in target
room No. 1 was used in the research experiments on theheaviest elements and in the study of the physical andchemical properties of these elements using a gas-filled
recoil isotope separator (GARIS). The e2 beam course intarget room No. 1 and the e6 beam course in target room No.
2 were used in the study of radiation chemistry and in the
study of accelerator mass spectrometry, respectively.
This year, research experiments on the heaviest elements
were carried out for 57 days in January and February, 4days in June, and 4 days in July.
Table 3. Operation statistics on two ion sources(18G-ECRIS and 28G-SCECRIS) in 2009; thestatistics include preliminary work time. The durations
for which the 28G-SCECRIS was in operation are
indicated in parentheses.

Ion

Mass

He

4

1

440.0

( 0.0 )

O

16

2

61.5

( 0.0 )

O

18

5

109.5

( 0.0 )

Ne

22

6

129.5

( 0.0 )

Na

23

71454.0( 0.0 )

Ar

40

11

244.0

( 0.0 )

%

Ca

48

10

340.0

( 0.0 )

Fe

58

13

365.0

( 0.0 )

Xe

136

20, 27, (20)388.0 ( 56.0 )U

23835, (35)

404.5 ( 711.0 )3936.0 ( 767.0 )Table 2. Beam service time of the stand-alone RILAC
allotted to each beam course in target rooms No. 1
and No. 2 of RILAC in 2009.
Beam course

Total time (h)

e2

59.5

3.7

e3

1520.0

95.2

e6

17.0

1.1

Total

1596.5100.0- 291 -

Charge state

Total

Total time (h)Statistics on the operation times for the year 2009 of an
18-GHz ECR ion source (18G-ECRIS) and a new 28-GHz
superconducting ECR ion source (28G-SCECRIS) that use
an existing 18-GHz microwave power source are listed inTable 3. The ion beams of 10 elements were used in various
experiments, in beam acceleration tests, and in beamcommissioning.
In order to increase in the intensity of the 238U ion beam
for the RIBF, we carried out the following installation tasks
and beam tests during this reporting period:1) The 28G-SCECRIS on the high-voltage terminal of
the Cockcroft-Walton pre-injector (HV-Terminal)
was incorporated in all devices. In May 2009, theplasma of the 28G-SCECRIS was successfully
generated using an existing 18-GHz microwave
power source.
2) The low-energy beam transport (LEBT) line on the
HV-Terminal and the medium-energy beam transport(MEBT) line were installed. These beam transportlines are connected to a new acceleration tube. The
ion beam extracted from the 28G-SCECRIS can bedirectly injected to the RILAC through the LEBT
and MEBT lines. The installation of these lines was
successfully completed in July 2009.
3) The beam acceleration test at RILAC was started inJuly 2009. At first, we used the 136Xe20+ beam, which
was extracted from the 28G-SCECRIS.
4) Tests on the production of Au ions and U ions at the
28G-SCECRIS were carried out from October toNovember 2009.
5) As a result, we started supplying the 238U35+ beam forexperiments at the RIBF from November 2009.
We carried out the following improvements and overhauls
during this reporting period:1) In the rf system for rf power amplifiers No. 1, No. 3,
and No. 4, rf pickup probes of the cavities and auto
gain controllers, were improved.
2) In the rf systems, power supplies at the final stages
and the intermediate stages were subjected to annual
inspection. In addition, major components ofmechanical parts were subjected to a simple
inspection.
3) The installation of new power supplies for dipole
magnets (DMe1, DMe3, DMe4, and DMe5) wascompleted in March 2009. The power supplies for
DMe3, DMe4, and DMe5 were replaced with new
ones. We are temporarily using the power supply forDMe1 to excite an analyzing dipole magnet on the
HV-Terminal.
4) A turbomolecular pump of the RILAC cavity No. 2
was replaced with cryogenic pumps. The othervacuum pumps were subjected to annual inspection.
5) All the water pumps of each water-cooling systemwere subjected to a simple inspection. Two heatexchangers for the ordinary water-cooling circuitand the deionized water-cooling circuit for RILAC
were overhauled. All cooling towers were subjected
to a monthly inspection and annual cleaning.

A decelerator of the Charge-State Multiplier system(CSM-D1) was removed from the beam transportline in target room No. 2 in May 2009 and wasconverted to the drift tube linac No. 3 (DTL3) cavity
of a new injector linac (RILAC2). The empty section
was connected by an aluminum tube for vacuum
plumbing.
7) In the e2 beam course, magnets of a new gas-filled
recoil isotope separator were installed in May 2009.
Therefore, the existing experimental devices
belonging to two users were removed. The
experimental devices belonging to one of the users
were reinstalled in the e6 beam course in June 2009.
The devices belonging to the other user will bereinstalled in a different beam course.
We experienced the following mechanical problems
during this reporting period:
1) Water splashed on a magnet power supply for themillercoil for the 18G-ECRIS because of leakage
from a drain valve of the magnets on an upper floor;
we repaired the valve.
2) Water splashed on a high-voltage DC power supply
for the 28G-SCECRIS because of leakage from awater joint for the sputtering electrode; we repaired
the joint.
3) A re-buncher was damaged in an accident during
the installation of the MEBT line. Fortunately, thedamage was rectified.
4) Water splashed on an rf power amplifier system of
the FC-RFQ because of leakage from a water jointof the cryogenic pump on an upper floor; werepaired the joint.
5) There were problems in the rf power amplifiersystems, DC power supplies, low-level controllers,
wide-band amplifiers, and a programmable logic
controller; we replaced each component with sparecomponents.
6) The bellows and pipe of a vacuum chamber in target
room No. 1 were damaged in an accident during thereinstallation of the dipole magnet (DMe2); we
repaired these components.
7) An electrical motor of the ordinary water pump for
the RILAC cavities and magnets broke downbecause of the insulation failure in a coil phase. It
was replaced immediately with an inactive electrical
motor of the other water circuit, in accordance withspecifications.
8) A thermostatically controlled valve of the deionizedwater circuit for the CSM suffered from a problem
caused by the deterioration failure of the gasket
material; we repaired the valve.
9) An air-cooling fan of the cooling tower circuit for
RILAC suffered from a problem caused by thebreakage of the bearing assembly; we repaired thefan.

- 292 -

6)

RIKEN Accel. Prog. Rep. 43 (2010)

AVF cyclotron operation
M. Kase, T. Kageyama, N. Tsukiori,*2 Y. Ohshiro,*1 N. Fukunishi, T. Nakagawa, H. Okuno, N. Sakamoto,
M. Fujimaki, M. Kidera, M. Komiyama, Y. Higurashi, M. Nagase, S. Yokouchi, K. Yamada,
H. Hasebe, K. Suda, H. Kuboki, T. Maie, K. Kobayashi,*2 M. Nishida,*2 Y. Kotaka,*2 S. Fukuzawa,*2
T. Nakamura,*2 R. Koyama,*2 K. Yadomi,*2 S. Ishikawa,*2 M. Hamanaka,*2 M. Nishimura,*2 J. Shibata,*2
A. Goto, O. Kamigaito, and Y. Yano*1
CNS: Center of Nuclear Study, Graduate School of Science, the University of Tokyo*2
SHI Accelerator Service Ltd.
Table 1 shows the operation statistics of the RIKEN

were not delivered due to certain problems with the RF

K70-MeV AVF cyclotron (hereafter denoted as AVF) for

transmitter of the Hyper-ECR ion source. In December

2009 together with those for the preceding years.

The

2009, a cooling water leakage occurred at AVF RF amplifier

total operation time of 3870 h in 2009 is greater than that in#1, and the CRIB experiment by the Korean group could

2008 by 8% and is equal to that in 2006, when regular RIBF

not be performed well.

operation had not started.

As an annual university curriculum, four sets of one-day

In 2009, RIBF experiments involving the use ofexperiments were conducted by students belonging to therelatively light ion beams were performed for the first time.

University of Tokyo in autumn 2009. Elastic scattering

For these experiments, the AVF was operated as an injector

experiments involving the use of 6MeV/u α-beam were

and the acceleration mode of AVF-RRC-SRC was operated

performed in the vacuum chamber on the way of the CRIB

for 550 h. In spring 2009, a nitrogen beam and a polarizedcourse in E7.

deuteron beam were accelerated and injected into the

The E7b beam line was used frequently in 2009 for

RRC-SRC-BigRIPS; the final energy of the beam was

general purposes. Experiments on the electrochemistry of

250MeV/u.

seaborgium and on α fine structure spectroscopy were

In April, the polarized deuteron beam wasproduced in the PIS after a long time and accelerated by the

conducted frequently.

AVF. A single-turn extraction for the deuteron beam could

single-bunch Ar beam with an energy of 4 MeV/u was used

be done well, which is significant for the experiment.

to the Mossbauer experiment. The parallel-plate chopper

In September, a well-defined

The AVF injection mode for the RIPS experiments which

was used in an ion-source beam line with a voltage of 1 kV

requires high-intensity beams of solid ions were changed toand a repetition rate of 1 MHz; the resultant beam intensity

the RILAC injection mode in order to examine the ion

is approximately 10 pnA. Mixing of adjacent bunch to thesource performance.

single bunch was reduced to less than 0.1%.

Eventually, the operation time of

AVF-RRC decreased by 33% compared to that in theprevious year.

It is third year since the RI productions for charged
distribution began in 2007. The C03 target station has

In standalone operations of the AVF, a total of 817 h was

been used frequently for this purpose. Radio-nuclides ofdedicated in 2009 to the CRIB experiments, which has been65

Zn and 109Cd were produced using a 14-MeV proton beam

managed by CNS, the University of Tokyo. This value isand delivered to facilities outside RIKEN by the Japan

smaller than that in 2008 by 30%. This decrease is partly

Radioisotope Association.

due to the fact that the CRIB experiments have been

In summer 2009, a new hot laboratory was completed inefficiently performed in the previous years and the number

the ion-source room just above the C03 target station. Itsof experiments on the backlog list is small.

location permits a quick transportation of RI product the

However,some of the CRIB experiments involving the use of Li ion

target.

beam were cancelled in 2009. Intense and stable beams

expected in the new hot laboratory. In order to make a- 293 -The efficient treatments of the RI product arespace for the new laboratory, the old 10-GHz ECR ion

Tsukuba University, began to produce ions in spring 2009; itsource, which is relatively large, was replaced by themainly produces the gaseous ions. The alternate use of thesuper-conducting ECR ion source in 2008.

two ion sources, the Hyper ECR ion source and the super

The new

SCECRIS, which is jointly operated by RIKEN, CNS andconducting ECR source, became possible.

- 294 -

RIKEN Accel. Prog. Rep. 43 (2010).

Beam time statistics for user experiments
T. Suda, M. Kase, and T. Fujinawa

The operation of the RIBF for FY2009 was planed
according to the approved budget for the fiscal year, plans
for machine commissioning and construction, andbeam-time requests from experimenters who have the PAC
approved experimental proposals.
In this report, beam-time related statistics are presented.
Figure 1 shows the number of experiments anddevelopments performed and their duration in 2009. The
experiments are categorized on the basis ofaccelerator-operation
modes,
namely,experiments
involving the stand-alone operation of the AVF cyclotron,
the stand-alone operation of RILAC, the use of the RRC,
and the use of new accelerator complex named RIBF.
Figure 2 shows the total electric consumption profile forfacility operation of Nishina Center for FY2009 categorized
into those from TEPCO (Tokyo Electric Power Company)
and those generated using our CGS (Co-generation system).
Fig. 1 Statistics of the number of experiments anddevelopments performed and their duration in the year 2009.

Fig. 2 The total electric consumption profile for facility operation of Nishina Center.

- 295 -

 RIKEN Accel. Prog. Rep. 43 (2010)


PA C Meetings for Nucle ar Physics, and Material and Life Scienc eT. Suda, K. Ishida, and Y. Kobayashi
Two Program Advisory Committees (PACs) areresponsible for reviewing submitted proposals in the fields
of nuclear physics (NP) and material and life science (ML).
Each PAC holds meetings twice a year and reviews the
proposals.
The NP-PAC is co-organized by RIKEN Nishina Centerand CNS, Univ. of Tokyo.
The ML-PAC reviews
experimental programs at RAL and RIBF.
NP-PACThe NP-PAC meetings were held on June 18-19 and on
Dec. 2-4 this year1). The statics of the meetings are shownin Table 1.
ML-PACThis year, the ML-PAC meeting was held only once on
September 3-42). Due to the long shutdown period of RAL
in the latter half of FY2009, the 6th PAC meeting has been
postponed to FY2010. The statics of the meeting are shownin Table 2.

PAC members
NP-PAC : W. F. Henning (ANL, the chair), M. Huyse(K.U.Leuven), M. Lewitowicz (GANIL), K. Langanke (GSI),
R. Tribble ( Texas A&M ), T. Glasmacher ( MSU ), W. Liu(CIAE), A. A. Ogloblin (Kurchatov), B. Fulton (Univ. ofYork), A. Ono (Tohoku Univ.), K. Yabana (Univ. of
Tsukuba), I. Hamamoto (Lund Univ.), T. Kishimoto (RCNP),
T. Noro (Kyushu Univ.), T. Nakamura (Tokyo Inst. Of
Technology), T. Shimoda (Osaka Univ.), H. Sakai (Univ. ofTokyo)
ML-PAC : J. M. Poutissou (TRIUMF, the chair), A.
Amato (PSI), B. A. Beer (Univ. of Victoria), F. Hanaoka(Gakushuuin Univ.), R. Kato (RIKEN), K. Komaki (National
Center for Univ. Entrance Exam.), K. Kubo (ICU), D. E.
MacLaughlin (UC, Riverside), S. Maekawa (Tohoku Univ.),
K. Nagamine (UC, Riverside), N. Nishida (Tokyo Inst. Of
Technology), K. Nishiyama (KEK), F. L. Pratt (RAL), I.
Yamaguchi (Food Angri. Mat. Inspection), J. Zmeskal(Stefan Meyer Inst.)

Table 1. Statistics of the NP-PAC meetings held this year.

Table 2. Statistics of the ML-PAC meeting held this year.

References
1) http://www.nishina.riken.jp/UsersGuide/NP-PAC
2) http://www.nishina.riken.jp/UsersGuide/ML-PAC/- 296 -

RIKEN Accel. Prog. Rep. 43 (2010)

Radiation Safety Management at RIBF
Y. Uwamino, H. Sakamoto, R. Hirunuma Higurashi, H. Mukai*1, A. Akashio, H. Fukuda, S. Fujita, T. Yamaki, K. Igarashi, K.
Nakano and S. Iizuka

Table 1. Dose rates measured along beam lines in 2009.
Points 1−32 indicate the measurement locations shown in
Fig. 2.
Point

2008

Year

2006

1

2004

10

above a bending magnet that guides the beam from the RRC
vault to the distribution corridor. The neutron dose was
5.3±3.3 Sv/y, and the gamma dose was below thedetection limit of 4 Sv/y. The annual neutron dose in thecomputer room since 1999 is shown in Fig. 3.
The water from the closed cooling systems at BigRIPS
was sampled after the operation by using a 320-MeV/u 4He
beam, which had an intensity of approximately 1 pA, in
November 2009, and radionuclide concentrations were
measured by using a liquid-scintillation counter and a Ge
detector. The results are shown in Table 2. The radionuclide
concentration was highest in the cooling water at theside-wall beam dump, but the sum of ratios of theconcentrations to the legal limits for the drain water over all
the radionuclides was still considerably lower than unity.
The range of the 4He beam was long, and the cooling water
was directly irradiated by the primary beam. This 4He beamincreased the 3H concentration in the cooling water at theside-wall beam dump from 0.36 Bq/cm3 to 1.0 Bq/cm3.

AVF
RRC
SRC
2002

2

2000

10

1998

3

1996

10

1994

4

1992

10

1990

5

1988

10

1986

Dose rate (Sv/h)Residual radioactivity in cyclotron deflectors wasmeasured, and variations in the dose rates since 1986 areshown in Fig. 1. Since 2006, intense beam has been used at
AVF cyclotron for radioisotope production; this has beenaccompanied by a high of the residual radiation. RRC wasoperated with a 0.4-pA 135-MeV/u 14N beam until twodays before the measurement in 2009, and the dose rate wasfound to be extremely high, 100 mSv/h. The dose rate of theresidual radiation in the deflector of SRC was firstmeasured 28 days after the operation with a 50-pnA
250-MeV/u 14N beam.
The residual radioactivity was measured along beamlines after almost every experiment. Spots 1–32, marked
with solid circles in Fig. 2, are the points where high dose
rates were observed. Table 1 shows these dose rates alongwith the measurement dates, beam conditions, and decay
periods after the end of the operation. The maximum dose
rate was found to be 2.0 mSv/h at point 25, which is thesurface of the G01 Faraday cup placed after SRC.
We continuously monitor the radiation in and around the
RIBF facility by using neutron and gamma-ray area
monitors. Measurement of dose rates outside the radiationcontrolled area is difficult due to the presence of naturalradiation. No accelerator was operated between August 11
and September 4 in 2009, and the dose rates during thisperiod were assumed to be the natural background dose rate.
The net accumulated dose, i.e., the dose obtained after
subtracting the background dose, at the site boundary was
lower than the detection limit, which was assumed to be 9
Sv/y for gamma-rays and 2 Sv/y for neutrons. In any
case, the annual dose at the site boundary was considerably
lower than the legally permissible limit (1 mSv/y).
Three monitors are placed at the boundary of theradiation-controlled area. One is in the computer room of
the Nishina building and two are on the roofs of the IRC
and BigRIPS vaults. The highest value was observed in thecomputer room, which is on the ground floor immediately

Fig. 1. Dose rate at the deflectors of RRC, AVF, and SRC
since 1986. .
＊1

Japan Environment Research Corp.

- 297 -

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32

Dose
rate
(μSv/h)

400
1000
400
1000
35
38
20
35
35
23
160
1700
1600
1000
130
55
85
33
400
45
10
58
14
100
2000
16
50
35
12
180
110
900

Date Particle Energy Intensity Decay
period(M/D)(MeV/u) (pnA)
(h)

8/17
8/17
8/17
8/17
8/17
5/22
5/22
8/17
8/17
5/22
8/17
8/17
8/17
8/17
5/22
8/17
6/25
6/25
6/25
6/25
5/22
5/22
5/22
3/31
3/31
5/22
5/22
5/22
5/22
5/22
5/22
2/26

40

Ar
Ar
40
Ar
13
C
13
C
84
Kr
84
Kr
13
C
13
C
84
Kr
13
C
13
C
13
C
13
C
84
Kr
13
C
14
N
14
N
14
N
14
N
14
N
14
N
14
N
14
N
14
N
14
N
14
N
14
N
14
N
14
N
14
N
48
Ca
40

3.97
3.97
3.97
100
100
70
70
100
100
70
100
100
100
100
70
100
135
135
135
135
109
109
250
250
250
250
250
250
250
250
250
345

12
12
12
550
550
20
20
550
550
20
550
550
550
550
20
550
429
429
429
429
100
100
1
50
50
1
1
1
1
1
1
160

130
130
130
176
176
97
97
176
176
98
176
176
176
176
98
176
314
314
314
314
169
169
243
20
20
243
243
243
246
246
246
1620

Fig. 2. Layout of beam lines at RIBF. Locations where a high dose rate was observed are indicated by solid circles, 1−32.
10Annual dose (Sv/y)

8

6

4

2

0

1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009Year

Fig. 3. Annual dose of the leakage radiation in the computerroom of Nishina building since 1999.
Table 2. Radionuclide concentration in the cooling water of
BigRIPS on November 16, 2009, the legally permissible
limits for radionuclides concentration in the drain water,
and the ratio of the concentration to the limit.
cooling water
nuclide concentration 3 limit ratio tolimit(Bq/cm )3
F0 targetH
4.1e-21)60
6.8e-4
3
Exit beam dump
H
1.0e-160
1.7e-3
3
1.04
60
1.7e-2
H
Side-wall beam
7Be
2.0e-130
6.7e-3dump
sum 2.4e-2
1) read as 4.1×10-2
The radiation safety interlock system of Nishina building
was replaced in February 2009. A conceptual block diagramof the new system is shown in Fig. 4. The main
programmable logic controller (PLC) reads the status of theshield doors, safety keys, emergency stop buttons, andradiation monitors. On the basis of the status and the control
commands given by the accelerator operators or theradiation safety staffs, the main PLC controls the beam
stoppers, radiation shutters, electric power to the shielddoors, exhaust dampers, warning sirens, and beam statusindicators. The control commands are entered on the control
PCs, and the commands are transferred to the PLC by the
database server.
The access-control system is a part of the safety system.
It consists of access controllers at the boundaries of theradiation-controlled area and at the entrances of theaccelerator rooms and experimental rooms, and personal
contamination monitors.
The access controller reads the barcode on the personal
dosimeters, and records the entry of people into theradiation-controlled area and rooms. When the system
recognizes the existence of persons in a room, it inhibits
beam transport to the room. The system does not permit aperson to leave the area, until the personal contamination
monitor confirms the absence of contamination.
To avoid interruption of the accelerator operation by
problems in the database server or the LAN, a switch box isavailable. It is connected to the main PLC, and an
accelerator operator can directly control the main PLC
through the key box to continue the experiment. The safety
interlock system has shown good reliability since February
2009.

Fig. 4. Conceptual block diagram of the new radiationsafety interlock system of Nishina building.

- 298 -

RIKEN Accel.
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)
RIKEN

Fee-based distribution of radioisotopes produced at AVF cyclotron
T. Kambara, H. Haba, Y. Ezaki, K. Takahashi, and H. Miyamoto
Since October 2007, RIKEN Nishina Center has
been involved with fee-based distribution of radioisotopes (RIs) 65 Zn (T1/2 = 244 days) and 109 Cd (T1/2 =463 days) among the general public in collaboration
with the Japan Radioisotope Association1) (JRIA),
which is an organization of RI users and research workers and regulates the process from supply to disposalof RIs in Japan. According to a Material Transfer
Agreement (MTA) between JRIA and RIKEN,2) JRIA
receives orders from users, sends them to RIKEN, anddistributes the produced RIs from RIKEN to the users.
In 2009, we accepted four orders for 109 Cd and distributed total radioactivity of 30 MBq; and we also
accepted twelve orders for 65 Zn and distributed total
radioactivity of 51.1 MBq. Compared with 2008 when
we distributed 33 MBq of 109 Cd and 34.7 MBq of 65 Zn,
the distribution of 109 Cd showed a decrease of about
9% and that of 65 Zn showed an increase of about 47%.
These RIs were supplied to universities and research
institutes in Japan.
The 65 Zn and 109 Cd are produced by the65
Cu(p,n)65 Zn and 109 Ag(p,n)109 Cd reaction respectively with a 14-MeV proton beam from the AVF cyclotron at the C03 beam line dedicated to RI production. After irradiation, the RIs are separated by anion-exchange method to obtain 65 Zn and by precipitation and ion-exchange methods to obtain 109 Cd.
Recently, we have established techniques for the production and separation of a nuclide 88 Y (T1/2 = 107days), and it is now ready to join the list of RIs available for fee-based distribution. 88 Y was produced by
the 88 Sr(p,n)88 Y reaction. The target was a pellet ofstrontium oxide (SrO) with a diameter of 10 mm and a
thickness of 200 mg/cm2 , and SrO was prepared from
SrCO3 with a chemical purity of 99.99% and a natural
isotopic composition of 82.6% 88 Sr. A proton beamfrom the AVF cyclotron having a maximum intensityof 4.9 µA irradiated the target for 0.55 hours during
which the target placed on a target holder was cooled
by He gas and water. After the irradiation, 1.61 MBq
of 88 Y was separated using Eichrom Ln resin. The
chemical yield was 99.4%. We estimated the specificactivity of 88 Y to be 1.09 MBq/ng using ICP-MS.
In December 2009, the MTA was amended to add
the 88 Y to the list of nuclides available for distribution. Those who order the 88 Y can select its chemical
form among solutions in hydrochloric acid, acetic acid,and nitric acid with a concentration of 0.1 mol/L or 1
mol/L. The maximum radioactivity of one package is
1 MBq. Details can be found on the on-line orderingsystem J-RAM3) of JRIA.
Orders for RIs can be sent from any place inJapan to JRIA by Fax (03-5395-8055) or E-mail (gyomu1@jrias.or.jp). Normally, the RIs are delivered
within 16 days from the acceptance of the order.
References
1) http://www.jrias.or.jp/index.cfm/1,html (Japanese),
http://www.jrias.or.jp/index.cfm/11,html (English).
2) T. Kambara, H. Haba, Y. Ezaki, K. Takahashi, and H.
Miyamoto: RIKEN Accel. Prog. Rep. 42, 295 (2009).
3) https://www.j-ram.net/jram/DispatchTopPage.do (Japanese).

- 299 -

1

RIKEN Accel.
RIKEN
Accel. Prog.
Prog. Rep.
Rep. 43
43 (2010)(2010)

Operation of SRC cryogenic system
H. Okuno, T. Dantsuka, M. Kase, Y. Mori,∗1 , I. Tajima,∗1 , M. Ohshima,∗1 , K. Iwasaki,∗1 , T. Suzuki,∗1 , K.
Yamamoto,∗1 and S. Watanabe∗1[Superconducting ring cyclotron, cryogenic, helium refrigerator]

㻝㻢㻜

6

100
90

Pressure (Pa)

5

80
70

4

60
3

50
40

2

30

Temperature (K)The SRC cryogenic system, which consists of threecompressors, a He refrigerator, and four He buffertanks, was operated for around 9 months in 2009, witha 3-month maintenance shutdown in summer (June–
August). The most serious problem encountered during the operation was water leakage, in addition toother minor issues. These problems indicated that safe
long-term operation of the cryogenics system was difficult.
The long-term operation lasted from October 2008
to June 4, 2009, as shown in Fig. 1. The total operation period was around 230 days, during which period
oil contamination in the He refrigerator, which was amajor problem in 2008, was solved.
The first step in the shutdown of the cryogenic system was the recovery of 5000 L of liquid He from thesuperconducting magnets to the buffer tanks. In therecovery process, the TMP (Turbo Molecular Pump)sfor thermal insulation vacuum had to be switched on toevacuate the outgas from the cold mass whose temperature arise. Unfortunately, the above mentioned process however was delayed by 1-2 days owing to humanerror. Figure 2 shows the trend in the thermal insulation vacuum and cold-mass temperature. This deterioration caused cooling of the beam duct surroundedby the vacuum. The cooled beam duct caused the water in the copper pipe attached to the beam duct tofreeze and this led to rupture of the copper pipe, as
shown in Fig. 3. Asa a consequence, water entered thevacuum for until we could detect the leak. However,

20

1

10
0
㻢㻛㻠㻌㻜㻦㻜㻜

0㻢㻛㻠㻌㻠㻦㻠㻤

㻢㻛㻠㻌㻥㻦㻟㻢

㻢㻛㻠㻌㻝㻠㻦㻞㻠㻢㻛㻠㻌㻝㻥㻦㻝㻞㻢㻛㻡㻌㻜㻦㻜㻜

㻢㻛㻡㻌㻠㻦㻠㻤

Date and Time

Fig. 2. Trend in the vacuum for thermal insulation andtemperature for SBM cold mass after recovery wasstarted.

by this time, almost 30 tons of water had entered the
SRC. It was very difficult to remove the water and dry
the vacuum chamber and rf cavity. Nevertheless, we
successfully overcame this problem by autumn. Improvements had to be made the operation manual andalarm system in order to prevent the above mentioned
problem from recurring.
Operation of the compressors was started on August 29, 2009, after regular maintenance. The cryogenic system was maintained in the normal operation

Operations in 2008 - 2009㻲㼘㼛㼣㼞㼍㼠㼑㻌㻔㼓㻛㼟㻕

㻝㻡㻜
㻝㻠㻜

Operations in 2006 - 2007

㻝㻟㻜
㻝㻞㻜
㻝㻝㻜
㻝㻜㻜

㻜

㻡㻜
㻜㻡㻜㻢㻙㻜㻞

㻝㻜㻜㻝㻡㻜㻰㼍㼥㼟㻌㼒㼞㼛㼙㻌㼟㼠㼍㼞㼠㻌㼛㼒㻌㼟㼠㼑㼍㼐㼥㻌㼛㼜㼑㼞㼍㼠㼕㼛㼚㻌㻔㼐㼍㼥㻕㻜㻢㻜㻣㻙㻜㻝

㻜㻢㻜㻣㻙㻜㻞

㻜㻢㻜㻣㻙㻜㻟

㻜㻢㻜㻣㻙㻜㻠

㻜㻢㻜㻣㻙㻜㻡

㻞㻜㻜㻜㻡㻜㻢㻙㻜㻝

㻞㻡㻜㻜㻤㻝㻜㻙㻜㻝

Fig. 1. Flow-rate trend in the He refrigerator during the
2008–2009 operation and that during the 2006–2007 operation, which lasted for approximately 60 days.
∗1

Nippon Kucho Service Co., Ltd

Fig. 3. Broken copper pipe attached to the beam duct in
the SBM.

- 300 -

1

Return from Mag.
(2009/09)㪊㪇㪇㪫㪼㫄㫇䋨㪢䋩

Suppy to Mag.
(2005/09)

㪉㪇㪇

Return from Mag.
(2005/09)

㪈㪌㪇
㪈㪇㪇
㪌㪇
㪇

㪇

㪋㪏

㪐㪍

㪈㪋㪋

㪈㪐㪉

㪉㪋㪇

㪉㪏㪏

㪊㪊㪍

㪊㪏㪋

㪋㪊㪉

㪋㪏㪇

㪌㪉㪏

㪌㪎㪍

㪍㪉㪋

㪫㫀㫄㪼㩷㩿㪿㪀

100
90
80
70
60
50
40
30
20
10
0

102
100
98
96
94

Slide Valve (%)

㪉㪌㪇

Load ^Unload valve (%)

㪊㪌㪇

92
90
㻠㻦㻠㻤

㻣㻦㻝㻞

㻥㻦㻟㻢

㻝㻞㻦㻜㻜

㻝㻠㻦㻞㻠

㻝㻢㻦㻠㻤

Time

Fig. 4. Trend observed in the temperature of the supply
and return gas to/from the magnet in September 2009.
Trend observed in 2005 is also shown.

mode from October 12, 2009 to January 6, 2010; thefollowing minor problems were encountered during thisperiod. A purification process had to be carried out for
stable long-term operation before the superconducting
magnets were cooled. The compressors stopped working suddenly during the purification process because of
the failure of the 24-V power supply that was necessary
for the DI/DO VME board. Although the compressor
could be restarted after replacing the old power supply
with a new one, we learnt from this experience that adual power supply should be used for such importantdevices.
After purification, we started the cooldown operation. Figure 4 shows the trend in the temperature of
the supply and return gas used for the He refrigerator;
previously recorded data are also shown for comparison. The temperature of the supply gas never decreased below 12 K at the final stage of the cooldown
process. We found that the main supply valve ofCV5190 did not open even when the control display
showed its status as ”OPEN”; this was because thevalve for supplying compressed air to the pneumatic
control of CV5190 was closed. We realized that theoperator had forgotten to open the valve after the regular maintenance.
After cooldown, the vessels for the superconducting
magnets were filled with 5000 L of liquid He on October 19, 2009. We maintained the operation steady
until January 6, 2010. During the steady operation,
we encountered a new problem. At 9:59 AM on October 11, 2009, the slide valve in compressor A started toclose by few 5 %. The trend observed for the pressure
control valve suggested that operation was not stable
and that there was a very high risk of the operation
being interrupted, as shown in Fig. 5. We discussed
this unusual phenomenon with our colleagues. We decided that control of the slide valve is very importantfor protection against external factors. However, we

2- 301 -

Fig. 5. Trend in CV values observed for the slide valve incompressor A and valves used to control the suction andoutput pressure of the compressor.

could not identify the reason for automatic closing of
the control. We speculated that this was due to thefailure of the PLC programs and stopped the automated control of the slide valve.

RIKEN Accel. Prog. Rep. 43 (2010)

Present status of the BigRIPS cryogenic plant
K. Kusaka, M. Ohtake, T. Kubo, K. Yoshida, A. Yoshida, T. Ohnishi, Y. Yanagisawa, N. Fukuda, Y. Yano,
M. Nobutoki,＊1 H. Ito,＊2 T. Sasaki,＊2 N. Kakutani,＊2 T. Tsuchihasi,＊2 and K. Sato＊2
The
five
superconducting
tripletquadrupoles(STQ1–STQ5) in the first stage of the BigRIPS separator
are cooled by a large liquid-helium cryogenic plant, whose
main components are a Linde-TCF50S refrigerator (coldbox) and a Mayekawa 315-kW compressor unit.1) The
whole cryogenic system, including the STQs, wasfabricated by Toshiba Corporation and Taiyo Nippon Sanso
Corporation and installed in the RIBF building in early
2004.
Regular operation of the BigRIPS cryogenic plant started
in October 2006 after test operation was preformed fromMarch 2004 to June 2006.2,3) The cryogenic plant typicallyoperates according to the following thermal cycle:
purification of helium gas, precooling of the magnets,liquefaction, steady-state operation in the refrigerator mode,
and warm-up. Until July 2007, we repeated four thermal
cycles in which the periods of the steady-state operation in
the refrigerator mode were 53, 59, 39, and 34 days. The
cooling capacity decreased gradually in each operation
cycle, and we had to warm the cold box to recover thecooling capacity.
In February 2008, when the cryogenic valve at theentrance of the 80-K adsorber (ADS) was removed formaintenance, a small amount of oil was found on the valve
sheet. The oil contamination in the cold box wasinvestigated, and it was found that the heat exchangers andinternal high-pressure lines in the cold box were
contaminated. We concluded that the oil contamination in
the heat exchangers caused the decrease in the cooling
capacity. The oil-removal module of the compressor unit
was then improved, and the heat exchangers of the cold box
and the contaminated high-pressure lines were cleaned from
April to August 2008.4)
Our main compressor is a two-stage oil-flooded
screw-type with a flow rate of 73.5 g/s and a dischargepressure of 1.60 MPaG.
The improved five-stage
oil-removal module comprises an oil vessel with a demister
as a bulk oil separator (1SP), three coalescer vessels (2SP,
3SP, and 3.5SP), and two adsorbent vessels (4SP and 5SP)that contain activated charcoal and molecular sieves. The
design of the improved compressor unit is schematicallyshown in Fig. 1. The newly introduced third coalescer
vessel (3.5SP) is identical to the two original coalescer
vessels (2SP and 3SP), and the design of the final charcoal
vessel (5SP) is based on the oil-removal unit in the
RIKEN-RAL Muon facility. The compressor lubricant
injected in the screws is separated from the discharged
helium gas by using the five-stage oil-removal module, andthe oil contamination is expected to be 0.008–0.02 ppm.
＊1
＊2

Taiyo Nippon Sanso Corporation
Toshiba Corporation

Fig. 1. Schematic diagram of the improved compressor unit.
Continuous operation of the BigRIPS cryogenic plant
started on September 11, 2008. After one week ofcarrying out the purification operation, STQ1–STQ5 werecooled from room temperature to 4 K in 18 days, andcryostats were filled with liquid helium in 3 days.
Steady-state operation in the refrigerator mode started on
October 7, 2008, and ended on July 1, 2009. The plant
was operated in the steady state in the refrigerator mode for237 days, and the total operation time of the compressor
after the improvement was approximately 6500 h.

Fig. 2. T2 turbine flow rate and heater power in the periodof steady-state operation.
Figure 2 shows the flow rate of the T2 turbine and theheater power during the steady-state operation in the
refrigerator mode. From October 7 to early December,
we manually increased the inlet pressure of turbines tooptimize the cooling capacity so as to increase the T2 flow
rate. After December 6, we set the inlet pressure of
turbines at a constant value (1.23 MPaG) so as to maintain aconstant T2 flow rate. In the operations before July 2007,
the T2 flow rate decreased gradually even though the inlet
pressure was increased due to the oil contaminations.
The power of the magnet heater, shown in Fig. 2, is thesum of the heater power of the cryostats containing
STQ1– STQ5. The heater power of each cryostat is
automatically controlled such that the liquid helium level inthe cryostat remains constant. The power of the heater
installed in the phase separator (PS) in the cold box is also
shown in Fig. 2. The sum of the two curves of heater
power indicates that the excess cooling capacity of thecryogenic system is approximately 300 W at 4 K; this- 302 -

observation is consistent with the results of the test
operation in 2005. 2,3)

Fig. 3. Pressures at the exits of the compressor unit and thelast adsorbent vessel (5SP) and the supply pressure to the
80-K shield. The pressure drop across the heat exchanger
EX1 is also shown.
Figure 3 shows the variation in pressure in the highpressure part of the system. The discharge pressure of thecompressor unit is measured by a pressure transducer, andthe load and unload valves are operated such that thedischarge pressure is constant. When we cleaned the coldbox in 2008, we introduced differential pressuretransmitters in the cold box; these transmitters measure thepressure drop across the high-pressure line of the first heatexchanger (EX1). After we fixed the inlet pressure of
turbines on December 6, the measured differential pressure
was constant (~10 kPa), as shown in Fig. 3. We conclude
that the heat exchanger was not contaminated.
Figure 3 shows that the pressure at the exit of the 5SP,
which is measured by a Bourdon gauge, and the supply
pressure of the 80-K shield line as functions of the pressure
drop. Unlike the discharge pressure of the compressor unit,
the 5SP pressure and shield pressure decrease between
October 2008 and February 2009 and subsequently increase.
However, the difference between the 5SP pressure andshield pressure is almost constant; hence, we consider thatthe decrease in the 5SP pressure and shield pressure is notcaused by the contamination of the high-pressure line.
The temperature-drift of the pressure transducer may be thecause of the decrease in pressure.
In addition to the cold-box data, we adopted different
methods to study the oil contamination of the discharge
helium gas. The typical value of oil contamination
measured downstream of the coalescer vessels is 0.75–50
weight ppm. An “oil check kit” is used to measure thislevel of oil contamination. A fixed volume of gas issprayed through a controlled orifice onto a treated slide, andthe size of the oil spot on the slide is compared with that ofspots on a standard slide. We repeatedly measure the oil
contamination at the exit of the coalescer vessels by using
the oil check kit. Figure 4 shows the measurement at theexit of the 3SP, as an example of the results obtained using
the kit. An estimate of the oil drain from the 3.5SP is also
shown in Fig. 4. In our compressor unit, after sensing theoil level in the vessel, the drain oil in the coalescer vessels
is exhausted to the compressor via a drain line with solenoid
valves. By counting the number of times the solenoid

valve is operated or by manually measuring the amount of
the drain oil, we can estimate the level of oil contamination.
Both plots in Fig. 4 show gradual increase in the oil
contamination.
To measure oil contamination in the range 0.008–0.15
weight ppm, which is expected to be contamination level atthe exit of the adsorbent vessels, we used two different
methods. One method involves the use of an apparatus
called the pyrolyzer with multicomponent detector based on
optical emission spectrometry. We used Linde’s apparatus
and measured the oil contamination at the exit of 5SP for
two weeks in December 2008 and for three weeks in March
2009. The results for both periods indicate an oil
contamination of 0 ppb.
Another method to measure oil contamination in therange 0.008–0.15 weight ppm is a trap method in which
helium gas passes through a stainless steel sampler tube
containing glass beads and contaminant (oil) sticks on thesurface of the beads and/or the sampler tube. The
contaminant trapped in the sampler tube is then extractedusing a solvent, and the amount of the oil contaminant ismeasured by Fourier transform infrared (FTIR)
spectroscopy analysis. By introducing the sampler tube ina liquid-nitrogen Dewar, the trapping efficiency isimproved; we call this method as the “cold trap” (CT)method.
The CT method was applied to measure the oil
contamination at the exits of 5SP, 4SP, and 3.5SP. In all
three cases, results indicate that the oil contamination is
below the limits of 10, 41, and, 10 weight ppb, respectively.
The room-temperature trap method was also applied tomeasure the oil contamination at the exit of 3.5SP, and theoil contamination was evaluated to be less than 40 weightppb.
After the maintenance in summer 2009, continuous
operation of the cryogenic plant started on September 17,
2009. Steady-state operation in the refrigerator mode
started on October 9, 2009, and we are planning to carry out
the continuous operation till the end of June 2010.

Fig. 4. Oil contamination at the exit of the second coalescer
vessel (3SP)
References

1) T. Kubo et al.: RIKEN Accel. Prog. Rep. 36, 316 (2003).
2) T. Kubo et al.: RIKEN Accel. Prog. Rep. 38, 289 (2005).
3) K. Kusaka et al.: RIKEN Accel. Prog. Rep. 41, 244 (2008).
4) K. Kusaka et al.: RIKEN Accel. Prog. Rep. 42, 309 (2009).

- 303 -

RIKEN Accel. Prog. Rep. 43 (2010)

Present Status of Liquid-Helium Supply and Recovery System
T. Dantsuka, H. Okuno, Y. Odashima, M. Nakamura, T. Maie, K. Kato, K. Ikegami, M. Kase

M. Ohshima*, I. Tajima*, R. Ise* Nippon Air Conditioning Service K.K*
The liquid-helium supply and recovery system1), which cangenerate liquid helium at a rate of 200 L/h from pure helium
gas, has been stably operated since the beginning of April
2001. The volumes of liquid helium that were supplied eachyear are listed in Table 1 and also shown in Fig. 2. The
volume of liquid helium supplied has gradually increased
since the supply was started. The Exploratory Materials
Team began using liquid-helium for the first time in March
2008, the while the Laboratory for Human Brain Dynamics
at the Brain Science Institute (BSI) stopped using
liquid-helium by the end of September 2008.
We extended the recovery pipe at two places. First, at theend of January 2010, a new recovery pipe was connectedfrom the south side of the Laser Science Laboratory to therecovery station behind the building on the east at theBSI.
Next, new recovery pipes will be connected to the existing
pipe in the Nishina Memorial Building from E6 and J8; thiswill be done by the middle of August.
The control system of the compressor for liquefying heliumgas tripped several times between December 2009 andFebruary 2010. The cause for this is unknown and iscurrently being investigated.
The purity of the helium gas recovered from laboratories
improved gradually once the construction of the system wascompleted. The volume of the helium gas recovered fromeach building in the Wako campus and transported to theliquid-helium supply and recovery system was measured.
The recovery efficiency, which is defined as the ratio of therecovered helium gas to the supplied liquid helium, wasFiscal Year

2001

2002

Laboratory & institutecalculated. The recovery efficiency for the building on thesouth side of the Wako campus-such as the Cooperation
Center building of the Advanced Device Laboratory, theChemistry and Material Physics building, and the
Nanoscience Joint Laboratory building-increased to over
90%. Recovery efficiencies of the main research building
and the Laser Science Laboratory were 7.8%. The average
recovery efficiency from January 2008 to December 2009 isshown in Fig. 1. It has increased to over 90%..

References
1) K. Ikegami et al.: RIKEN Accel. Prog. Rep. 34, 349(2001).

Fig1. Average recovery efficiency measured fromJanuary 2008 to December 2009

2003

2004

2005

2006

2007

2008

Amount of supplied liquid helium (ℓ)

Magnetic materials laboratory

3392

7024

7713

11829

15672

16512

23282

20899

Low-temperature physics laboratory

1270

3090

6966

9515

34713

29520

39855

48756

Advanced device laboratory

9977

10849

9726

7401

11264

15017

14733

12554.5

1939

1615

3079

5353

5912

7772

5331

5459.5

Surface chemistry laboratory

1146

1676

4533

5007

5370

5486

3636

4080.5Brain science institute

6277

8144

5055

6292

7285

6956

6480

3226

624.5

9853.5Condensed molecular materials
laboratory

Exploratory materials team
Other laboratories
Total

3535

7730

14476

9487

15717

14767

14628.5

9862.5

27536

40182

51530

54884

95933

96030

109194114691.5- 304 -

Fig2. Volumes of liquid helium supplied to laboratories per year from fiscal 2001 to 2008

- 305 -

RIKEN Accel. Prog. Rep. 43 (2010)

Improvement made to couplers used for liquid-helium supply andrecovery lines (1)Y. Odashima, H. Okuno, M. Kase, T. Dantsuka, I. Tajima,∗1 , M. Ohshima,∗1 , R. Ise,∗1 and K. Kato[liquid helium, cryogenic system]
Workers at the liquid-helium plant transfer liquid
helium from a 7000-L Dewar to containers (100 L, 250
L) through a supply pipe. The users use this helium intheir laboratories for various experiments, connecting
the containers with recovery lines to the liquid helium
plant. We believe that it is important to establish aliquid-helium-handling system that can be safely handled by users and suppliers. For this purpose, we are in
the process of developing the process of new couplers
for liquid-helium supply and recovery lines, by taking
into account the suggestions given by the suppliers andusers. These couplers are expected to help overcome
the difficulties faced when handling liquid helium.
First, we describe the improvements made to thecoupler used for the liquid-helium-supplying line. Previously, the users employed Wilson seals for transferring helium to the experimental devices in the laboratory; on the other hand, a simple dynamic seal wasused when liquid helium was transferred to the container in the liquid-helium plant, as shown in Fig. 1.
The workers in the plant had to remove the Wilson
seal before pouring helium and then remove the frozen
Teflon tube to re-attach the Wilson seal. This process
was time-consuming, and there was a risk of losing theparts of the Wilson seal. Hence, we asked the users
to replace the Wilson seal with the dynamical-seal sothat the aforementioned process could be avoid. Fig.
2 shows the structure of a Teflon dynamic seal for theusers. A ditch was fabricated on the O-ring to preventthe leakage of helium.
Next, we describe the improvements made to thecoupler used for the helium-recovery lines. Before theimprovement, a conventional rubber hose was used.
The disadvantage of the rubber hose is the possible
leakage of helium; further, the hose may become rigid
when used for liquid-helium transfer and may have to
be warmed with a heat gun fro easy detachments. We
developed a cryogenic coupler by adding a check valve
to a conventional coupler. We replaced the O-ring andthin Teflon plate with a thick packing, as shown in
Fig. 3. In this case, no leakage was observed ever at
low temperatures such as around 30K, and the pipe forrecovery from the container could be easily detached atlower temperatures when the pressure in the container
decreased to 0 bar. Figure 4 shows a photograph ofthe coupler connecting the container the recovery line.

∗1

6TCPUHGTVWDG&[PCOKEUGCN

9KNUQPUGCN

6GHNQPTWDDGT
VWDGKPVJGJGNKWORNCPVKPVJGWUGTUNCDQTCVQT[

Fig. 1. The sealing structure when a transfer tube is added
to a port of the container in the helium plant and thein the user’s laboratory.

Ditch for O-ring

Fig. 2. A drawing of the dynamic seal newly developed forthe users.

Nippon Kucho Service Co., Ltd- 306 -

Fig. 3. Modified coupler with a thick packing developed forthe recovery line.

Fig. 4. The container is connected to the recovery line using
the newly developed cryogenic coupler.

2- 307 -

V. RECORDS OF LABORATORIES,GROUPS, AND TEAMS(Activities and Members)

Events of Nishina Center & CNS from Jan. 2009 to Mar. 20102009
13-14,Jan. ML-PAC
15-17,Jan. Nishina Center Advisory Council (NCAC)
Dec.-Mar.

266

Bh production experimentMar. SHARAQ(Spectroscopy of Hadronic Systems with Radioactive QuantumBeam) Commissioning
17,Mar. Laboratory assessment (periodical review) for Radiation Laboratory
24,Mar. Laboratory assessment for Heavy Ion Nuclear Physics Laboratory
18,Apr.

RIKEN Wako Institute Open Campus Day
18,May Joint ISIS/RIKEN Muon Facility Development Symposium at Abingdon,
Oxford, England
2,Jun. RBRC Management and Steering Committee on videoconference
18-19,Jun. NP-PAC
30,Jun SHARAQ Ceremony of its completion
3,Jul. Scientific Policy Committee of Nishina Center
7,Jul. The signing ceremony of the Memorandum of Understanding promoting
research collaboration between Nishina Center and TRIUMF
15,Jul. Press Release "Strongest beam in the world enables scientists to explore laws
governing all matter in the universe"
26,Aug.-2,Sep. CNS-EFES Summer School CNS-EFES09
3-4,Sep. ML-PAC
29,Sep.-8,Oct. Nishina School
3-4,Dec. NP-PAC
22,Dec. Press Release "Neon isotope reveals new type of neutron halo"
24,Dec. The microtron for the SCRIT facility has successfully produced electron beamof 150MeV
Dec. Application for trademark registration of breeds for "Nishina Otome" toMinistry of Agriculture, Forestry and Fishery of Japan2010
14,Jan. Press Release "New cherry blossom tree blooms in all four seasons"20-21,Jan. RIKEN Symposium "Muon Science at the RIKEN-RAL Muon Facility 2009"15,Feb.

Press Release "'Perfect' Liquid Hot Enough to be Quark Soup"---Protons,
neutrons melt to produce ‘quark-gluon plasma’ at RHIC---- 309 -

㪫㪿㪼㫆㫉㪼㫋㫀㪺㪸㫃㩷㪩㪼㫊㪼㪸㫉㪺㪿㩷㪛㫀㫍㫀㫊㫀㫆㫅㩷㪫㪿㪼㫆㫉㪼㫋㫀㪺㪸㫃㩷㪧㪿㫐㫊㫀㪺㫊㩷㪣㪸㪹㫆㫉㪸㫋㫆㫉㫐㩷
1. Abstract
The aim of this laboratory is to reveal the laws of nature ranging from elementary particles to theuniverse. More precisely, the following three issues are pursued with their mutual relations
emphasized:(1) Understanding the microscopic fundamental law of nature. In particular, trying togive a consistent definition of superstring and derive all the fundamental laws from one principle.
(2) Understanding many-body systems. Both of the following two aspects are considered. One is
the universal laws such as thermodynamics and the universality of spin systems, and the other is
specific properties of individual systems such as hadrons, condensed matter, and the universe. (3)Computational science. Besides numerical analyses as an important tool for the above mentioned(1) and (2), aspects of fundamental mathematics are also pursued.
2. Major Research Subjects(1) Constructive Definition of String Theory as Fundamental law of Physics(2) Fundamental aspects of Quantum Field Theory and its applications(3) High precision inspection of experimental and observational data
3. Summary of Research Activity
The ability to understand nature at its most profound level is a basic human desire. Science isfounded on accumulated and tremendous efforts driven by that aspiration. The objective of ourlaboratory is to participate in the endeavor to better understand nature by adding our contributions
to theoretical physics. The present seems to be a particularly exciting time for this as many
developments appear to be about to converge and allow formation of the ultimate theory of
everything.
We organize our research activities into three segments: the pursuit of the microscopic
fundamental laws of physics, the study of many-body systems, and the science and technology ofcomputation. These three aspects have an inseparable interrelation and are investigated in an
integrated manner throughout the research conducted within this laboratory.
(1) Understanding the fundamental law of nature through string theory.
1)Scale transformation and AdS/CFT correspondence
A scale transformation in the world sheet description of D3-branes in Type IIB theory was studied.
It was shown that this transformation is a real stringy symmetry in a region near D3-branes. By
using this symmetry, Wilson loops in N = 4 supersymmetric Yang-Mills theory are explicitly
related to minimal surfaces in the AdS space, and the AdS/CFT correspondence follows naturally
as a consequence of this symmetry. This argument was generalized to the correspondence for highenergy scattering amplitudes of N = 4 super-Yang-Mills theory and to the AdS/CFT
correspondence at finite temperature. It turned out that various forms of the AdS/CFT
correspondence can be understood in a unified manner as a consequence of this stringy scaletransformation.
2) Matrix models and curved space-time
Incorporating curved space time into matrix models is pursued. In particular, a method in whichlarger additional degrees of freedom is introduced to represent space-time symmetry, is proposed.

- 310 -

3)Domain Wall in string theory
We investigate a global structure of the moduli space of the BPS domain wall system. I particular,
we are interested in the case where the dimensions of the moduli space is greater than those
expected from the index theorem. We also study the T-duality between the vortices and domain
walls from a string theoretical point of view. We explicitly construct a vortex solution in the Higgs
phase of supersymmetric gauge theory and find an exact correspondence between the solution andD-brane configuration in the domain wall side.
4)Non BPS branes and supergravity
We investigate the correspondences between a class of classical solutions of Type II supergravity(the three-parameter solution) and D-branes in the superstring theory. In addition to the mass, theRR-charge, the solution also carries the so-called dilaton charge, whose physical meaning was
unclear. We find that the appearance of the dilaton charge is a consequence of deformations of theboundary condition from that of the boundary state for BPS D-branes. We also show that suchdeformed boundary states are realized as tachyonic and/or massive excitations of the open strings
on D-brane systems.
5) Application of string theory to Nuclear physics
Holographic QCD, which is the application of the AdS/CFT correspondence to QCD, turns out tobe a very fruitful arena of research in string theory. Using holographic QCD technique, various
quantities which are difficult to calculate by perturbative QCD, lattice QCD and conventional
nuclear physics approach are investigated. For example, the decay rate of f0(1500) is calculatedsuggesting its connection to much sought glueballs.
(2) Quantum field theory and physics of many body systems
1)Lattice formulation of supersymmetric gauge theory
We proposed a lattice formulation of low dimensional supersymmetric gauge theories, aiming atpractical implementation for numerical simulations.
2) Lattice formulation of fermions coupled to gravity
We formulated lattice Dirac operator of the overlap-type that describes the propagation of a Diracfermion in a gravitational field. We also analyzed global gauge anomalies associated withMajorana fermions in 8k and 8k+1 dimensions.
3)Mathematical aspects of 2-dimensional gauge theories and string.
We investigate a non-perturbative correction to the N=2 supersymmetric Yang-Mills theory fromthe discrete matrix model point of view. We utilize the D-brane picture in superstring theory andlocalization theorem in order to derive the discrete matrix model from 2-dimensional Yang-Mills
theory on a compact 2-cycles in the ALE space. We also find the relationship to the
Dijkgraaf-Vafa theory in the continuum limit.

4)Quantum field theory over the deformed commutation relation
A quantum theory of free scalar field based on the deformed Heisenberg algebra which is thecorrection of stringy physics is constructed.

- 311 -

(3) High precision calculation of field theory and computational science
1)High precision calculation of QED
We have announced the final result of our calculation of the electron anomalous magnetic
moment. It contains up to the eighth-order of the perturbation theory of QED. The very reliable
result was obtained by using high precision calculation on RIKEN’s supercomputer system(RSCC).
We also succeeded in automating the calculation of the tenth-order of the perturbation theory,
particularly in constructing the ultra-violet subtraction terms. This is an important step toaccelerate our calculation of the entire tenth-order contribution.
The dominant contribution from the tenth order to the muon anomalous magnetic moment wasalso announced by us. In contrast to the electron, some specific Feynman diagrams give rise to thelarge contributions to the muon anomaly. We explicitly evaluated about 2000 Feynman diagrams
which are possible to give the leading and next-to-leading contributions.
2)Improved perturbation method and its applications
We apply improved perturbation method which is one of the variational schemes to Ising model in
two-dimensions. It enables us to evaluate free energy and magnetization at strong couplingregions from weak coupling expansion even in the presence of the phase transition.
We determine approximated transition point in this scheme. In the presence of external magnetic
field we can see not only stable physical states but metastable one. This reserach motivated byavailability of this method to IIB matrix model which is expected to show a phase transition from
10-dimensional universe to 4-dimensional universe.

Head
Hikaru KAWAI
Members
Hiroshi SUZUKI
Koji HASHIMOTO
Tsukasa TADA
Postdoctoral Researchers
Isao KISHIMOTO
Daisuke KADOH
Ta-sheng TAI
Koichi MURAKAMI
Yutaka SAKAMURA
Yutaka BABA
Minoru ETO
Yasuyuki HATSUDA- 312 -

Contract Researchers
Makiko MATSUKAWA
Visiting Scientists
Hajime AOKI (Fac. of Sci. and Eng., Saga Univ.)
Jiro ARAFUNE (National Inst. for Academic Degrees and Univ. Evaluation)
ZyunF. EZAWA (Grad. Sch. of Sci., Tohoku Univ.)
Kazuo FUJIKAWA (College of Sci. and Tech., Nihon Univ.)
Masashi HAYAKAWA (Grad. Sch. of Sci., Nagoya Univ.)
Takeo INAMI (Fac. of Sci. and Eng., Chuo Univ.)
Nobuyuki ISHIBASI (Grad. Sch. of Pure and Applied Sci., Univ. of Tsukuba,)
Satoshi ISO (High Energy Accelerator Res. Organization)
Hiroshi ITOYAMA (Grad. Sch. of Sci., Osaka City Univ.)
Toichiro KINOSHITA (Cornell Univ., USA)
Yoshihisa KITAZAWA (High Energy Accelerator Res. Organization)
Ivan KOSTOV (Service de Physique Theorique, CNRS, FRANCE)
Didina SERBAN (Service de Physique Theorique, CE-Saclay, FRANCE)
Dhar AVINASH (Tata Institute of Fundamental Research)
Jnanadeva MAHARANA (Inst. of Phys., INDIA)
Jun NISHIMURA (High Energy Accelerator Res. Organization)
Fumihiko SUGINO (Okayama Inst. for Quantum Phys.)Asato TSUCHIYA (Fac. Of Sci., Shizuoka Univ.)
Tatsumi AOYAMA (High Energy Accelerator Res. Organization)
Shoichi MIDORIKAWA (Aomori Univ.)
Masanori HANADA (Weizmann Inst.)
Issaku KANAMORI (Univ. of Torino)
Yuuichirou SHIBUSA (Nagasaki Institute of Applied Science)
Kazutoshi OHTA (Meiji Gakuin Univ.)
Muneto NITTA (Keio Univ.)
Norisuke Sakai (Tokyo Woman’s Christian University)
Research Consultants
Keiji IGI
Hironari MIYAZAWA
Yoshio YAMAGUCHI
Masao NINOMIYA
Junior Research Associate
Secretary
Yumi KURAMITSU
Yoko SAGIYA- 313 -

����������� �������� ��������
����������� ������� ������� ����������
1. Abstract
Nuclei are finite many-particle systems composed of protons and neutrons. They are self-boundin femto-scale (10-15m) by the strong interaction (nuclear force) whose study was pioneered by
Hideki Yukawa. Uncommon properties of the nuclear force (repulsive core, spin-isospin
dependence, tensor force, etc.) prevent complete microscopic studies of nuclear structure. Thereexist number of unsolved problems even at present. In addition, radioactive beam facilities
reveal novel aspects of unstable nuclei. We are tackling these old problems and new issues intheoretical nuclear physics, developing new models and pursuing large-scale calculations ofquantum many-body systems. We are also strongly involved in research on other quantum
many-body systems, to resolve mysteries in the quantum physics
2. Major Research Subjects(1) Nuclear structure and quantum reaction theories(2) First-principle calculations with the density functional theory for many Fermion systems(3) Computational nuclear physics
3. Summary of Research Activity(1) Finite amplitude method for nuclear response calculations
We are performing a systematic calculation of nuclear photoabsorption cross section for lightnuclei. The calculation is fully self-consistent and is based on the time-dependent
density-functional theory with the Skyrme functional. This is achieved using the finite
amplitude method we have recently developed. The key feature of the method is to obtain thematrix elements of the random-phase approximation (RPA) in a simple way avoiding explicit
calculation of induced residual fields. The method is called “Finite amplitude method” (FAM).
So far, even-even nuclei up to mass number A=100 have been studied.
We have also been developing a new theoretical tool to apply the finite amplitude method tonuclei with superfluidity. Then, we have been involved in the implementation of the FAM on an
existing spherically symmetric Hartree-Fock-Bogoliubov code (HFBRAD) which is currently
being turned into a quasi-particle-random-phase approximation (QRPA) code.
(2) Many-body green's function approaches to nuclear structure
Green's functions theory using modern realistic nuclear interactions was applied to study 56Ni
and 48Ca. This allowed us to investigate the role of different types of correlations on the problemof quenching of the spectroscopic factors. Based on this success, the dependence of nuclear
correlations on proton-neutron asymmetry is being investigated. The "state of the art" Green's
function theory was also benchmarked on the ground state energy of 4He, where accuracies of100-200 keV or less were found. This shows the feasibility of ab-initio studies with this method.
Analogous calculations have been performed for electronic systems (atoms) to aid indevelopments of density functional theory.
(3) Low-lying collective modes in deformed neutron-rich nuclei- 314 -

Low-frequency negative-parity excitations in deformed neutron-rich nuclei have been studied
with the self-consistent Hartree-Fock-Bogoliubov and the QRPA. The Skyrme energy density
functional together with the pairing energy density functional is adopted. We found a significant
coupling effect between the dipole and the octupole excitations for the pygmy resonance inneutron-rich Mg isotopes.
(4) Spectroscopic study of odd-mass nuclei
The quasi-particle-vibration-coupling Hamiltonian has been derived in a framework of thenuclear density functional method to describe the low-lying properties of odd-mass nuclei in a
microscopic way. We applied it to the electric-quadrupole moments of neutron-rich Al isotopes
around N=20, and showed an important role of neutron pairing correlations implying aweakening of the N=20 shell gap. The results show a reasonable agreement with recent
experimental data.
(5) Linear response calculation using the canonical-basis TDHFB with a schematic pairing
functional
Aiming at constructing a theoretical framework that is able to analyze and predict properties of
unknown nuclei, we proposed the Canonical-basis time-dependent Hartree-Fock-Bogoliubov(Cb-TDHFB) approach in the three-dimensional coordinate-space representation. In thisapproach, we assume that the time evolution can be described by the time-dependent canonicalbasis with the time-dependent (u,v) factors. We have shown that this can be achieved only when
we use a special pairing functional. The computer program with the Skyrme functional has beendeveloped and applied to E1 and E2 nuclear response.
(6) Microscopic description of large-amplitude quadrupole collective dynamics in low-lying
statesWe have proposed a microscopic method to calculate the vibrational and rotational inertial
functions, which includes the time-odd contribution of the mean-field, in the Bohr-Mottelsoncollective Hamiltonian for large-amplitude quadrupole collective dynamics. The method iscomposed of constrained HFB and the local QRPA equations, which are derived from theadiabatic self-consistent collective coordinate method. The method is applied to shapecoexistence and anharmonic vibrations in Se isotopes, and we have shown that the time-odd
mean field increases the collective inertial functions and lowers the excitation energies.
(7) Phenomenological analysis of the oblate-prolate symmetry breaking in triaxial deformation
dynamics
In this study, we have analyzed the effects of the oblate-prolate symmetry breaking on dynamics
of triaxial deformation in oblate-prolate shape coexistence phenomena using a simple model
based on the well-known quadruploe collective Hamiltonian. We have obtained a number ofinteresting suggestions through the numerical solutions of this model: (i) The relative energy ofthe excited 0+ state can be a signature of the potential shape along the γ direction. (ii) SpecificE2 transition probabilities are sensitive to the breaking of the oblate-prolate symmetry. (iii)
Nuclear rotation may induce the localization of collective wave
functions in the quadrupole deformation space if the oblate-prolate symmetry in the moments
of inertia is broken.

- 315 -

(8) Structures of superdeformed states in 28Si and 40Ar
Structures in 28Si and 40Ar have been studied using the antisymmetrized molecular dynamics(AMD) method. The oblate-prolate shape coexistence is reproduced and existence ofsuperdeformed (SD) band is predicted for 28Si. The SD states contain alpha-24Mg cluster
structure components. For 40Ar, the SD band is reproduced, which were experimentally
identified very recently. The calculation suggests that the SD states form triaxial shapes, and theKπ = 2+ side band exists.
(9) Nuclear “pasta” in supernova
We aim to bridge between astrophysics and nuclear and atomic physics by solving astrophysicalproblems using nuclear/atomic physics and by providing interesting nuclear/atomic physics
problems in astrophysical systems. This year, we have solved a long-standing problem about theformation of rod-like and slab-like nuclei referred to as "pasta" nuclei in collapsing supernova
cores. In the field of cold atom physics, we have studied the critical velocity of unitary Fermi
superfluids flowing in a periodic potential. Unitary Fermi gases resemble the low density
dripped neutron gases in neutron stars and this work also provides useful information to study
neutron star crusts and the related phenomena.
(10) Study of vortex lattices in cold Fermi gases
We are developing a theoretical framework to describe both the vortex structure in rotatingcondensates and the band-structure of Fermi superfluids in a periodic potential. This year, wehave developed a new efficient scheme to create a Schroedinger cat-like maximally entangledstate in a two-state Bose system.
(11) Phenomenological formulae for nuclear reaction cross sections
We examine the mass-number dependence of the cross section formula based on theblack-sphere picture of nucleus. We find analytically that, in contrast to other formulae, ourformula includes A1/6-dependence in addition to A2/3-dependence. The A1/6-dependence, whichcomes from the optical depth of target nucleus, is one of the characteristic features of ourformula.
We study the scaling properties of proton-nucleus total reaction cross sections for stable nuclei,
2 / 3 total
and propose an approximate expression just in proportion to Z 2 / 3σ total
σ pn . Based on
pp + N
this expression, we can derive a relation that enables us to predict a total reaction cross section
for any stable nucleus within at most 10% uncertainty, using the empirical value of the total
reaction cross section of a given nucleus.

Head
Takashi NAKATSUKASA
Members
Akihisa KOHAMA- 316 -

Special Postdoctoral Researchers
Yasutaka TANIGUCHI
Nobuo HINOHARA
Kenichi YOSHIDA
Gentaro WATANABE
Foreign Postdoctoral Researcher
Carlo BARBIERI
Contract Researcher
Paolo AVOGADORO
Senior Visiting Scientist
Kenichi MATSUYANAGI
Research Consultants
Kiyomi IKEDA
Syuhei YAMAJI
Kosai TANABE
Visiting Scientists
Yasuhisa ABE (RCNP)
Anatolijs AFANASJEVS (Mississippi State Univ.)
Shigeyoshi AOYAMA (Niigata Univ.)
Yoshihiro ARITOMO (JINR)
Simone BARONI (Univ. of Washington)
Carlos BERTULIANI (Texas A&M Univ.)
Satoshi CHIBA (Japan Atomic Energy Agency.)
TiebKhoa DAO (Inst. Nucl. Scie. Tech.)Elisabeth ELSTER (Ohio Univ.)
Yoshiko ENYO (Yukawa Inst. Theoretical Phys.)
Hubert FLOCARD (INP-Orsay)
Yasuro FNAKI (Univ. Tsukuba)
Koichi HAGINO (Tohoku Univ.)
Ikuko HAMAMOTO (Lund Univ.)
Koji HIGASHIYAMA (Chiba Institute of Technology)
Nobuo HINOHARA (Yukawa Inst. Theoretical Phys.)
Michio HONMA (Aizu Univ.)
Takatoshi HORIBATA (Aomori Univ.)
Munetake ICHIMURA (The Open Univ of Japan)
Kei IIDA (Kochi Univ.)
Akitsu IKEDA (Shizuoka Inst. Scie. Tech.)
Tsunenori INAKURA (Grad. Sch. of Pure and Applied Sci., Univ. Tsukuba)- 317 -Naoyuki ITAGAKI (Univ of Tokyo)
Akira IWAMOTO (Japan Atomic Energy Agency)
Meng JIE (Peking Univ.)
Kiyoshi KATO (Hokkaido Univ.)
Toshitaka KAZINO (NAOJ)
Masaaki KIMURA (Hokkaido Univ.)
Wenhui LONG (Peking Univ.)
Masayuki MATSUO (Tohoku Univ.)
Takuma MATSUMOTO (Hokkaido Univ.)
Bradley MEYER (Clemson Univ.)
Kazuo MUTO (Tokyo Institute of Technology)
Takayuki MYO (Osaka Univ.)
Kazusuke OGATA (Kyushu Univ.)
Makito OI (Univ of Surrey.)
Akira ONO (Tohoku Univ.)
Masahisa OTA (Konan Univ.)
Kazuhiro OYAMATSU (Aichi Shukutoku Univ.)
Hiroyuki SAGAWA (Aizu Univ.)
Badawy SARHAN (Cairo Univ.)
Ryoichi SEKI (California Univ.)
Noritaka SHIMIZU (Univ of Tokyo)
Yoshihumi SHIMIZU (Kyushu Univ.)
Kosuke SUMIYOSHI (Numazu National College of Technology)
Akihiro SUZUKI (Suzuki Corporation)
Yasuyuki SUZUKI (Niigata Univ.)
Toshio SUZUKI (Fukui Univ.)
Naoki TAJIMA (Univ of Fukui)
Masatoshi TAKANO (Waseda Univ.)
Masaaki TAKASHINA (RCNP)
Kazuo TAKAYANAGI (Sophia Univ.)
Noboru TAKIGAWA (Tohoku Univ.)
Kazuko TANABE (Otsuma Women's Univ.)
Jun TERASAKI (Univ. North Carolina)
Yutaka UTSUNO (Japan Atomic Energy Agency.)
Takahiro WADA (Kansai Univ.)
Kazuhiro YABANA (Grad. Sch. of Pure and Applied Sci., Univ. Tsukuba)
Taiichi YAMADA (Kanto Gakuin Univ.)
Masayuki YAMAGAMI (Aizu Univ.)
Naotaka YOSHINAGA (Saitama Univ.)
Yumin ZHAO (Shanghai Jiao Tong Univ.)
Students
Junior Research Associates- 318 -

Shuichiro EBATA (Grad. Sch. of Pure and Applied Sci., Univ. Tsukuba)
Koichi SATO (Dept. Phys., Kyoto Univ.)
InternFabien LAINE (Pari-Sud 11 Univ.)
Hakim TAKLANTI (Pari-Sud 12 Univ.)
Student Trainees
Wataru HORIUCHI (Niigata Univ.)
Secretary
Shinko ODAI

- 319 -

㪫㪿㪼㫆㫉㪼㫋㫀㪺㪸㫃㩷㪩㪼㫊㪼㪸㫉㪺㪿㩷㪛㫀㫍㫀㫊㫀㫆㫅㩷㪪㫋㫉㪸㫅㪾㪼㫅㪼㫊㫊㩷㪥㫌㪺㫃㪼㪸㫉㩷㪧㪿㫐㫊㫀㪺㫊㩷㪣㪸㪹㫆㫉㪸㫋㫆㫉㫐㩷
1. Abstract
We proposed accurate few-body calculational method called “Infinitesimally shifted Gaussian
lobe method”. Recently, we developed this method to four-body systems and five-bodysystems. This method is applicable for various three- and four-body systems. For example, weapplied it to hypernuclear physics and clarified what is important and impressed. In fact, weapplied this method to three kinds of hypernuclear experiments (KEK-E419, BNL-E930, and–E929) in the past, and we contributed to these experiments by discussing withexperimentalists, analyzing the data, and interpreting the data.
2. Major Research Subjects(1) Hypernuclear structure from the view point of few-body problem(2) Structure of exotic hadron system(3) Baryon-baryon interaction based on lattice QCD(4) Neutron-rich Λ hypernuclei from shell model approach
3. Summary of Research Activity(1) The structure of the T=1 isotriplet hypernuclei, 7HeΛ, 7LiΛ, 7BeΛ within the framework of an
α+Λ+N+N four-body cluster model is studied. The Λ binding energy of the ground state in7
HeΛ which is under analysis at JLAB by (e,e’K+ ) reaction is predicted to be 5.16 (5.36) MeV
with (without) the CSB interaction.
(2) A theoretical approach based on the shell model is presented to calculate effective charge ofelectric quadrupole transitions. The shell-model calculation with single-particle 2h-barω
excitations in the first order perturbation qualitatively reproduces existing B(E2) values forcarbon isotopes with neutron number 5≼ N ≼16 and shows a sudden change of the isovector
effective charge beyond N=8.

Head
Emiko HIYAMA
Contract Researchers
Atsushi UMEYA
Visiting Scientists
Yasuo YAMAMOTO (Tsuru University)
Taiichi YAMADA (Kanto Gakuin University)
Tetsuo HYODO (Tokyo Institute of Technology)
Makoto OKA (Tokyo Institute of Technology)
Tomokazu FUKUDA (Osaka Electro-Communication University)
Daisuke JIDO (YITP, Kyoto University)
Yoichi IKEDA (University of Tokyo)- 320 -

Hidekatsu NEMURA (Tohoku University)
Soichi ISHIKAWA (Hosei University)
Takenori FURUMOTO (Osaka City University)
Atsushi HOSAKA (RCNP, Osaka University)
Shoji SHINMURA (Gifu University)
Akinobu DOTE (HIGH ENERGY ACCELERATOR RESEARCH ORGANIZATION,
KEK)
Thomas RIJKEN (Radboud University Nijmegen)
Kazuma NAKAZAWA (Gifu University)
Research Consultants
Masayasu KAMIMURA
Kiyomi IKEDA
Student Trainees
Kaori HORII (RCNP, Osaka University)
JRA
Hitomi NODA (Tokyo Institute of Technology)
Secretary
Makiko OHISHI- 321 -

��� ������� ������ �������� ��������
��������� ����������
1. Abstract
Nucleons, such as protons and neutrons, are a bound state of constituent quarks glued together withgluons. The detail structure of nucleons, however, is not well understood yet. Especially themechanism to build up the spin of proton, which is 1/2, is a major problem in physics of the strong
force. The research goal of Radiation Laboratory is to solve this fundamental question using the firstpolarized-proton collider, realized at RHIC, Brookhaven National Laboratory (BNL) in USA. RHIC
stands for Relativistic Heavy Ion Collider, aiming also to create Quark Gluon Plasma, the state of
Universe just after the Big Bang. RIKEN-BNL Research Center (RBRC) directed by N. Samios
carries our core team at BNL for those exciting researches. Recent data analysis has shown that the
proton spin carried by gluons is indeed small, which is a very striking finding beyond our
expectations. We have been doing other pioneering researches at the domestic accelerators at
SPring-8 and High Energy Accelerator Research Organization (KEK) which is now preceded to the
new experiment at J-PARC. We are also performing technical developments such as novel ion sources,
fine pitch pixel detectors and neutron optical devices.
2. Major Research subjects
1) Spin physics with relativistic polarized-proton collisions at RHIC
2) Study of nuclear matter at high temperature and/or at high density
3) Technical developments on radiation detectors and accelerators
3. Summary of Research Activity（1） Experimental study of spin structure of proton using RHIC polarized proton collider[See: RIKEN-BNL Research Center Experimental Group]（2） Experimental study of quark-gluon plasma using RHIC heavy ion collider[See: RIKEN-BNL Research Center Experimental Group]（3） Study of properties of mesons and exotic hadrons with domestic accelerators
Hadrons with more than three quarks are of great interest and have been looked for over the past 30
years. The Θ+ is a genuine exotic baryon with the minimum quark configuration of u, u, d, d andanti-s. After the first report on the evidence of the Θ+ at SPring-8/LEPS in 2002, evidence andcounterevidence have been reported from all over the world, but its existence is not conclusive yet.
We have made effort to establish the Θ+ since our first report. In 2009, we reported again theobservation of the Θ+ with clean and high statistics data at SPring-8/LEPS [Phys.Rev.C 79,
025210 (2009)].
In addition, we are searching for Θ+ with three times higher statistics. The results will be open soon.
The spin and parity of Θ+ is quite important to understand the internal structure of Θ+ . The
mechanism of Θ+ production with vector meson, K*(890), is sensitive to parity of Θ+ . The
analysis aiming for the measurement of ( Θ+ , K*(890)) production is underway. In order toestablish the Θ+ and explore the world of multiquark hadrons, R & D work is underway to construct
LEPS-II, which is a new beam line and detectors at SPring-8.
Preparation of the experiment E16 at J-PARC 50-GeV PS is ongoing to obtain the full approval by
PAC. The experiment aims to perform the systematic study of the mass modification of low-mass
vector mesons in nuclei to explore the chiral symmetry in nuclear matter. GEM tracker andhadron-blind Cherenkov counter (HBD) are being developed for the experiment. In the beam tests,- 322 -

incident-angle dependence of the position resolution was studied for the tracker . At the same time,several photoelectrons were successfully observed by the HBD and improvement the prototype
detector is underway.
（4） Detector development for PHENIX experiment
We have been developing the silicon vertex tracker (VTX) in order to enhance physics capability of
the PHENIX detector at RHIC. It consists of two inner layers of pixel detectors and two outer layersof strip detectors. Radiation Laboratory group is responsible for the ladder fabrication of the pixel
detector. The production of the ladder has been started. Seven of the ladders are assembled and tested
with production version of readout electronics.
We also have been developing the momentum-sensitive trigger system for the PHENIX muon arms
under the collaboration with KEK, Kyoto and Rikkyo University. All additional electronics which
generate fast trigger signal were installed on the muon arm and has been commissioned.
（5） Neutron optics
Cold or thermal neutron beam is a high-sensitivity probe to study not only the structure ofcondensed matter, but also nuclear and particle physics. However, its realistic applications are still
limited since the numbers of available neutron sources are small and their intensities are low. This
project aims to enhance the efficiency in using those precious neutron beams by improving theneutron beam optics, in order to maximize scientific outputs within a short period of time. Base on
the developed technologies, devices are fabricated and distributed to other laboratories anduniversities by “Riken Venture Company”, Japan Neutron Optics Inc.
We stay with the fundamental physics research in a new beam line at 1MW Pulse Spallation
Neutron Source in J-PARC. This beam line was designed by applying our knowledge and techniqueof neutron optics. We also succeed to observe interference signals of cold neutrons using the Si
crystal interferometer at JRR-3M. There, we are developing a new type of instrument forphase-difference imaging with use of the gratings developed by us. We are also planning to study
neutron Electron Dipole Moment using a perfect crystal at the J-PARC beam line.
The fact that permeability of the neutron beam for metals whose atomic number is large and thickcement attracts attention to various engineering fields.
This year the vision to develop so small neutron source that in some day we use it outside as aportable neutron source instruments is becoming more and more a reality.
In this project, the various ways of imaging using neutron beam are trial survey and under thedevelopment, including not only neutron radiography but phase differential imaging, CT-imaging
using special technique which is founded in VCAD project in RIKEN. We are now collaborating with
VCAD project program team to realize small neutron source.
（6） Theoretical study of hadron physics
Nuclear matter at finite temperature and density has been studied in lattice simulations of quantum
chromodynamics (QCD) which is the first principle to describe the interactions of quarks and gluons.
Several properties of QCD phase transition from hadronic matter to quark-gluon plasma have been
investigated with calculations of Polyakov-loop correlations and quark number susceptibilities. A
new approach to calculate the equation of state have also been derived and developed in the full-QCD
simulations which include dynamical quarks of up, down and strange flavors. Study of hadron andchiral properties in finite temperature and density is going on.
In continuation of the studies on the fragmentation functions based on the Nambu-Jona-Lasiniomodel, the effect of pion multiple production processes is taken into account in a modified version of
the quark-jet model originally proposed by Field and Feynman. The effect is found to be crucial andthe calculated fragmentation function for the pion qualitatively reproduces the experimental one.

- 323 -

In connection with the Unruh effect, the hydrogen-like system in a uniformly accelerated frame isstudied using the analogy with the Stark effect. The energy shift as well as the decay width iscalculated by the WKB method.
The tetraquark is studied in quenched lattice QCD simulation to see whether the state exists or notfrom the first principle calculation of QCD. By performing the diagonalization, the energy
eigenvalues are obtained for isospin zero and JP=1± channels. The volume dependence of the energy
eigenvalues are checked to distinguish between bound or resonance state and scattering state. As aresult, no evidence of existence of the tetraquark is obtained within our calculation.

Head
Hideto EN’YO
Members
Yasuyuki AKIBA
Yuji GOTO
Itaru NAKAGAWA
Yoshie OTAKE
Atsushi TAKETANI
Yasushi WATANABE
Satoshi YOKKAICHISpecial Postdoctoral Researchers
Masayuki NIIYAMA
Kazuya AOKITomohiro NISHITANI
Foreign Postdoctoral Researcher
Stephen BAUMGART
Contract Researchers
Yoshinori FUKAO
Hideaki IIDA
Maki KUROSAWA
Kenichi NAKANO
Tomoaki NAKAMURA
Yu MAESAWA
Contract Technical Scientist
Yohei NAKATSUGAWA
Research Consultant
Katsuya HIROTA- 324 -

Senior Visiting Scientists
Ken-ichi IMAI (Grad. Sch. of Sci., Kyoto Univ.)
Toshiaki SHIBATA (Grad. Sch. of Sci. and Eng., Tokyo Inst. of Tech. Sch. of Sci.)
Hirohiko SHIMIZU (Inst. of Materials Structure Sci., KEK)
Ken-ichi AOKI (Grad. Sch. of Sci., Kanazawa Univ.)
Koichi YAZAKI (Tokyo Woman’s Christian Univ.)
Takashi NAKANO (RCNP, Osaka Univ.)
Visiting Scientists
Tomohiro ADACHI (DAI-ICHI KIDEN CO.,LTD)
ChristineA. AIDALA (Univ. Massachusetts, Amherst, USA)
Alexander BAZILEVSKY (BNL, USA)
Wolfgang BENTZ (Tokai Univ.)
Mickey CHIU (Univ. of Illinois at Urbana, USA)
Ondrej CHVALA (Univ. of California at Riverside)
Takumi DOI (University of Kentucky)
Dipanwita DUTTA (Nuclear Physics Division, Bhabha Atomic Research Centre)
Hirotsugu FUJII (Grad. Sch. /College of Arts and Sciences, Univ. of Tokyo)
Kenji FUKUSHIMA (YITP, Kyoto Univ.)
Haruhiko FUNAHASHI (Grad. Sch. of Sci., Kyoto Univ.)
Takashi HACHIYA (Private Company)
Yuji HASEGAWA (Wien Inst. Tech.)
Tetsuo HATSUDA (Grad. Sch. of Sci., Univ. of Tokyo)
Toshiyuki HATTORI (Res. Lab. for Nuclear Reactors, Tokyo Inst. of Tech. Sch. of Sci.)
Masanori HIRAI (Grad. Sch. of Sci. and Eng., Tokyo Inst. of Tech.)
Kensuke HONMA (Grad. Sch. of Sci., Hiroshima Univ.)
Takuma HORAGUCHI (Grad. Sch. of Sci., Hiroshima Univ.)
Ryo ICHIMIYA (KEK)
Katsuya ISHIGURO (Grad. Sch. of Natural Sci. & Tech., Kanazawa Univ.)
Noriyoshi ISHII (Grad. Sch. of Pure and Applied Sci., Univ. of Tsukuba)
Hirokazu ISHINO (Tokyo Inst.Tech.)
Robert JAMESON (Goethe Universitat Frankfurt, Germany)Takeshi KANESUE (Kyushu Univ.)
Hirotsugu KASHIWAGI (Takasaki Advanced Radiation Res. Inst., JAEA)
Hiroyuki KAWAMURA (The Univ.of Liverpool)
Akio KIYOMICHI (KEK)
Yuji KOIKE (Grad. Sch. of Sci. & Tech., Niigata Univ.)
Yoshiaki KOMA (Numazu National College of Technology )Kotaro KONDO (Grad. Sch. of Sci. and Eng., Tokyo Inst. of Tech.)Dmitiri KOTCHETKOV (Univ. New Mexico, USA)
Shunzo KUMANO (Inst. of Particle and Nuclear Studies, KEK)
Teiji KUNIHIRO (Yukawa Inst. for Theoretical Phys., Kyoto Univ.)
Han LIU (Phys. Dept., New Mexico State Univ.)
Yoshikazu MAEDA (RCNP, Osaka Univ.)- 325 -

Yajun MAO (Peking Univ., China)
Tsutomu MIBE (KEK)
Liu MING (LANL)
Kenji MISHIMA (KEK)Yoshiyuki MIYACHI (Tokyo Inst. Tech.)
Yoshihiro MORI (Grad. Sch. of Sci., Kanazawa Univ.)
Norihito MURAMATSU (RCNP, Osaka Univ.)
Ryotaro MUTO (KEK)
Katsuro NAKAMURA (Grad. Sch. of Sci., Kyoto Univ.)
Yoshifumi NAKAMURA (DESY, Germany)
Atsushi NAKAMURA (Information Media Center, Hiroshima Univ.)
Megumi NARUKI (KEK)
Munehisa OHTANI (Inst. fuer Theoretische Physik, Universitact Regensburg, Germany)
Hiromi OKADA (KEK)
Masahiro OKAMURA (BNL, USA)
Kyoichiro OZAWA (Grad. Sch. of Sci., Univ. of Tokyo)
Petra RIEDLER (CERN, Switzerland)
Naohito SAITO (J-PARC, KEK)
Murad SARSOUR (Georgia State University )Shoichi SASAKI (Grad. Sch. of Sci., Univ. of Tokyo)
Shin-ya SAWADA (Inst. of Particle and Nuclear Studies, KEK)
Michiko SEKIMOTO (Inst. of Particle and Nuclear Studies, KEK)
Kenta SHIGAKI (Grad. Sch. of Sci., Hiroshima Univ.)
Prashant SHUKLA (Nuclear Physics Division, Bhabha Atomic Research Centre)
Kazutaka SUDO (Inst. of Particle and Nuclear Studies, KEK)
Toru SUGITATE (Grad. Sch. of Sci., Hiroshima Univ.)
Mizuki SUMIHAMA (RCNP , Osaka Univ.)
Kazutaka SUMISAWA ( KEK)
Tsuneo SUZUKI (Grad. Sch. of Sci., Kanazawa Univ.)
Taneja SWADHIN (SUNY at Stony Brook)
Junpei TAKANO (KEK)
Kiyoshi TANIDA (Grad. Sch. of Sci., Kyoto Univ.)
Hisayuki TORII (Grad. Sch. of Sci., Hiroshima Univ.)
Xiaorong WANG (New Mexico State University)
Shizui WATANABE (Tokyo Metropolitan College of Aeronautical Engineering)
Imuran YOUNUS (Univ. of New Mexico, USA)
Visiting Researcher
Yoshichika SEKI (Fac. of Sci., Kyoto Univ.)
Students
Junior Research Associate
Yoki ARAMAKI (CNS, Univ. Tokyo)
Kimiaki HASHIMOTO (Fac. of Sci., Rikkyo Univ.)- 326 -

Kenichi KARATSU (Fac. of Sci., Kyoto Univ.)
Miki KASAI (Fac. of Sci., Rikkyo Univ.)
Misaki OUCHIDA (Facul. Science, Facul. Sci. Hiroshima Univ.)
Dosatsu SAKATA (Univ. Tsukuba)
Satoshi SANO (CNS , Univ.Tokyo)
Jun TAMURA (Grad. Sch. at Nagatsuta, Tokyo Inst.Technol.)
Yorito YAMAGUCHI (CNS, Univ. Tokyo)
International Program Associate
Ryu Sunyoung (RCNP, Osaka Univ.)

InternKohei SHOJI (Grad. Sch. of Sci., Kyoto Univ.)
Seishi DAIRAKU (Grad. Sch. of Sci., Kyoto Univ.)
Rei SAMESHIMA (Faculty of Science , Kyoto University)
Yudai ICHIKAWA (Faculty of Science , Kyoto University)
Shinichi MASUMOTO (Fac. Sci. , Univ. Tokyo)
Yusuke KOMATSU (Fac. Sci. , Univ. Tokyo)
Yosuke WATANABE (Fac. Sci. , Univ. Tokyo)
Kazuki UTSUNOMIYA (Fac. Sci. , Univ. Tokyo)

Student Trainees
Satoshi ADACHI (Faculty of Science , Kyoto University)
Hidemitsu ASANO (Grad. Sch. of Sci. & Eng., Saitama Univ.)
Yosuke HAKI (Fac. of Sci., Rikkyo Univ.)
Masayasu HASEGAWA (Grad. Sch. of Sci., Kanazawa Univ.)
Taku HUShouyang (China Inst. Atom. Energy)
Yuki IKEDA (Coll.Sci. , Rikkyo Univ.)
Yuuji KATOU (RCNP , Osaka Univ.)
Kotaro KIJIMA (Grad. Sch. of Sci., Hiroshima Univ.)
Toshiya KIMURA (SOKENDAI)Paul KLINE (Dept. of Physics , SUNY at Stony Brook)
Yuki KOBAYASHI (Tokyo Inst.Technol.)Andrew MANION (Dept. of Physics , SUNY at Stony Brook)Shunsuke MASUIKE (Tokyo Inst.Technol.)
Nathan MEANS (Dept. of Physics, SUNY at Stony Brook)
Shinji MOTOKI (Grad. Sch. of Biosphere Sci., Hiroshima Univ.)
Keiko MURANO (Inst. Phys. , Univ.Tsukuba)
Yoshihide NAKAMIYA (Grad. Sch. of Sci., Hiroshima Univ.)
Masaya NIHASHI (Facul. Science , Facul. Sci. Hiroshima Univ.)
Atsushi OKAMURA (Facul.Sci. , Kyoto Univ.)
Yuta SADA (Facul.Sci. , Kyoto Univ.)- 327 -

Tamotsu SATO (Fac. Sci. , Univ. Tokyo)
Takahiro SAWADA (RCNP, Osaka Univ.)
Satoru UEDA (Grad. Sch. of Pure and Applied Sciences, Univ. of Tsukuba)
Technical Staff
Junpei KANAYA
Secretaries
Noriko KIYAMA
Yoko SAKUMA- 328 -

㪪㫌㪹㩷㪥㫌㪺㫃㪼㪸㫉㩷㪪㫐㫊㫋㪼㫄㩷㪩㪼㫊㪼㪸㫉㪺㪿㩷㪛㫀㫍㫀㫊㫀㫆㫅㩷㪘㪻㫍㪸㫅㪺㪼㪻㩷㪤㪼㫊㫆㫅㩷㪪㪺㫀㪼㫅㪺㪼㩷㪣㪸㪹㫆㫉㪸㫋㫆㫉㫐㩷
1. Abstract
Particles like muons, pions, and kaons have finite life times, so they do not exist in natural
nuclei or matters. Implanting these particles into nuclei/matters, exotic phenomena invarieties of objects can be studied from a new point of view.
Kaon is the second lightest meson which has strange-quark as a constituent quark. It is
expected that if one embed a kaon into nuclei, the sizes of the nuclei become smaller and forms
a high density object beyond the normal nuclear density. Study of this object could lead tobetter understanding of the origin of the mass of the matter, and may reveal the quark degree of
freedom beyond the quark-confinement. Those properties can be studied by precise heavy
pionic atom research in different angle. The other example is the weak interaction in nuclear
matter. It can only be studied by the weak decay of hypernuclei, which have Lambda particle
in the nuclei,
Muon provides even wider variety of study from nuclear reaction to magnetism in matter.
For instance, stopping positively charged muon in a material, we obtain information on themagnetic properties or the local field at the trapped site. Injecting negatively charged muon
to mixture of deuterium and tritium, muon attracts surrounding atoms and is known to cause
d-t fusions.
As is already clear, in our research we introduce different kind of impurities into nuclei/matters,
and study new states of matter, new phenomena, or the object properties.
2. Major Research Subjects(1) Study of meson property and interaction in nuclei(2) Origin of matter mass / quark degree of freedom in nuclei(3) Condensed matter and material studies with muon(4) Nuclear and particle physics studies via muon catalyzed fusion and ultra cold muon beam(5) Materials science using Mössbauer spectroscopy
3. Summary of Research Activity
Hadron physics at J-PARC and RIKEN-RIBF
Kaon and pion will shed a new insight to the nuclear physics. The recent discovery of deeply
bound pionic atom enables us to investigate the properties of mesons in nuclear matter. At
RIKEN-RIBF, we are preparing precise experimental study of the pionic atom. We areintensively preparing another next generation kaon experiments (E15 and E17) at J-PARC as
day-one experiments. In these experiments, we are aiming at precise determination of the KN
interaction, and clarify the nature of kaon in nuclei. By these experiments, we aim to be aworld-leading scientific research group using these light meta-stable particles.
1) Deeply bound kaonic nuclei
We have performed experimental exploration of theoretically predicted deeply boundkaonic nuclear states in 3He nucleus K-ppn and K-pnn. Akaishi and Yamazaki first- 329 -

calculated large binding energy and narrow width for the K-ppn state. One of the mostinteresting features of the kaonic nucleus is that the strong attraction of the kaon is
expected to contract the surrounding nucleons resulting in extremely high density ofseveral times larger than normal nuclear density. Measurement of the kaon properties atsuch high energy density will provide precious information on the origin of hadron masses
and the chiral symmetry breaking and its partial restoration.
The experimental principle adopted uses stopped K- on suprefluid helium target, and we
focus on emitted nucleon momenta measurement by Time-of-Flight (TOF) method. The
last orbit of kaonic 4He atom is 2p and the branching ratio from the last orbit to the nuclear
kaon bound state accompanied with a nucleon emission was estimated to be 1 % at
minimum.
The exploration was performed from 2002/September till 2005/December as series ofexperiments at the KEK-PS (E471, E549, E570) with almost common experimental setup.
The obtained spectral shape was rather smooth and elaborate analysis showed uppper limitof the kaonic nucleus formation for both K-ppn and K-pnn states.
After the completion of above series of experiments, the KEK-PS was shut down to switch
to a new facility J-PARC. Presently, we are preparing for an experiment to search for K-pp
nuclear system at the K1.8BR beamline of the J-PARC.
2) Deeply bound pionic atoms
We have made precision spectroscopy of pionic lead and tin atoms, and extracted
information on the in-medium interaction between pion and nucleus, which leads to the
exclusive quantitative evaluation of the chiral symmetry restoration in the nuclear matter.
Our collaboration which mainly consists of the RIKEN and the University of Tokyo groupconducted throughout the experiments starting from R&D of pionic atom formation in
nuclear reactions to its application to the precision spectroscopy.
The experiment was carried out in GSI, Darmstadt. Our first discovery was pionic 2p statein the lead 207 nucleus where the negative pion is accommodated in a delicate balance
between the Coulomb attraction and the strong repulsion.
Following the discovery, we have performed experiments to measure 1s pionic lead 205
and tin 115, 119, and 123 isotopes.
We have analyzed the experimental spectra elaborately and extracted in-medium isovector
interaction between pion and nucleus. In combination with experimental information on
the pionic hydrogen and deuterium which gives the interaction in vacuum, we haveaccomplished evalution of the in-medium interaction modification. The modification isoriginating in the partial restoration of the chiral symmetry in the nucleus, and we havequantitatively evaluated for the first time the reduction of the chiral order parameter in the
nuclear matter to be 33 %, which is consistent with theoretical prediction of 30 %.
Presently, we have been preparing for a sophisticated experimental setup of the pionic
atom spectroscopy at the RIBF in the RIKEN. We expect about twice better experimental
resolution with much smaller systematic errors.
3) Precision X-ray measurement of kaonic atom
Simultaneously with the above experiment (1), we have performed an X-ray spectroscopy
of atomic 3d→2p transition of negatively charged K mesons captured by helium atoms.
Many Kaonic atoms are known to be measured with various elements, however, there are- 330 -

very large deviations in the measured energy levels for the helium (and the oxygen) fromthe systematic expectations. The deviation originates in technical issues in old experiments,
and new and high precision data have been long awaited for. Also, wave functions of theKaonic atoms are expected to reflect the information on the existence of the inner structure,
namely deeply bound Kaonic states. As a result of the experiment, we have succeeded inperforming the spectroscopy and achieved the shift of 2+-2(stat.) +-2(syst.) eV. The
obtained results reject older data beyond any doubt, and the above deviation is dissolved.
Presently, aiming at the determination of the level width and yield, we are analyzing thedata. To clarify the KN interaction strength, we are preparing another x-ray measurementof the kaonic helium-3 atom, which is another day-one experiment at J-PARC.
Muon science at RIKEN-RAL branch
The research area ranges over particle physics to condensed matter studies and life science.
Our core activities are based on the RIKEN-RAL Muon Facility located at the Rutherford
Appleton Laboratory (UK), which provides the most intense pulsed muon beam. We havevariety of important research activities such as muon-catalyzed fusion (μCF) and condensed
matter physics by muon spin rotation / relaxation / resonance (μSR).
(A) Condensed matter/materials studies with μSR
The world-first gas pressurized μSR setup has been established and its applications formaterial sciences have been started. The maximum pressure of the system is 6.4 kbar and thetemperature range is from 2 K to 300 K. The strong advantage of the system is to achieve thehomogeneous pressure in all temperature range and the pressure can be changed quickly
without removing samples from the spectrometer.
A new spectrometer named CHRONUS has been installed in Port-4 and commissioning works
are going on in order to optimize the performance of the new spectrometer. The spectrometerhas more than 600 detectors to minimize the counting loss and maximize the performance tomeasure tiny samples less than 20 mg. A platform of the Port-4 area is now being designed andthe installation will be done within 2010. After the completion of the Port-4 area, parallel
experiment at both Port-2 and Port-4 will be planned.
There are three topics of material sciences studied by the muon-spin relaxation method at
the RIKEN-RAL Muon facility in 2009.
1) The Li-diffusion behavior in Li-based batteries has been investigated. On the basis ofsome assumptions concerning the hopping behavior of the Li atom in batteries, thediffusion constant of the Li atom has been obtained. This value seems to be closer to therealistic value rather than those previously obtained by other experimental techniques.
2) A co-existing relationship between a magnetically ordered state and the superconducting
state in a newly found Fe-based superconducting oxide has been clarified. A competing
relationship between the magnetically ordered state of Fe spins and the superconducting
state has been suggested.
3) A three-dimensional coherent magnetic ordered state of radical spins in a
one-dimensional Co(II) molecular magnet has been detected. This is the second example
which show a long-range magnetic ordered state of radical spins in the family of the
one-dimensional molecular magnet. An important role of the magnetic interaction between
one-dimensional magnetic chains to the magnetism of the one-dimensional magnetic chain
has been suggested.

- 331 -

(B) Nuclear and particle physics studies via muon catalyzed fusion and ultra cold muon beam1) Muon catalyzed fusion (μCF)
We are studying the muon catalyzed fusion (μCF) processes in a wide range of hydrogentarget conditions such as isotope mixtures and temperatures. This year we constructed a
test high pressure target, which will enable us to keep D2 target in solid state up to 30 K,
thus we will be able to study μCF in high density and high temperature solid target, wherethe μCF is expected to occur much faster than in liquid.
2) Generation of ultra slow positive muon beam
Low energy muon beam, whose kinetic energy is variable from a few keV to a few tensof keV, will extend the scope of μSR technique from a bulk material to surfaces andmulti-layered materials. It is also expected that a very sharp beam of low energy muon
may enable a new way of precision measurement of muon's anomalous gyro-magnetic
ratio (g-2). Following the successful generation of slow muon beam by laser ionization ofthermally emitted muonium in vacuum, we plan to increase the slow muon beam intensity
by more than 100 times. For this purpose, we have started works such as construction of a
new intense laser system, search of materials for efficient muonium emission at room
temperature, and design of new slow muon microscope optics. The first part of the newlaser system was manufactured. We are preparing for a precise measurement of themuonium emission from material surface such as silica powder and silica aerogel incollaboration with TRIUMF.
Mössbauer spectroscopy at RIKEN-RIBF, HIMAC and CERN-ISOLDE
57
Fe Mössbauer spectroscopy following ion implantation of radioactive 57Mn (T1/2 = 1.45 min)has been applied to investigate the atomic jump processes of Fe impurity in Si semiconductor
in RIKEN-RIBF. 57Mn is one of the useful nuclear probes to study the dynamic behavior andchemical states of dilute Fe atoms in solid. Iron impurities are known to degrade seriously
electronic properties of silicon-based devices as well as solar cells. Generally, Fe atoms arethought to occupy only on interstitial sites in Si leading to a fast diffusion. In addition,
substitutional Fe atoms were not found experimentally by standard evaluation techniques. Ourinvestigation is to clarify the impurity diffusion of Fe atoms and the formation processes of“substitutional Fe atoms” in Si at high temperatures.
57
Mn implantation Mössbauer spectra from 800 K to 1200 K can be analyzed only by a broad
singlet. The area intensities decreased with increasing temperatures, as explained by Debye
model. The intensities suddenly decreased at 1000 K, but recovered again at 1100 K.
The relaxation behaviors observed in the present experiment can be interpreted in terms of adiffusion-reaction process of interstitial Fe atoms with vacancies within the time scale of 100
ns, leading to the formation of substitutional Fe atoms in the Si matrix. The process must be
related to the recovery processes from non-equilibrium to the equilibrium states of the Si
lattice around the 57Fe nuclear probes.
57
Mn implantation Mössbauer studies were performed to study the defect formations induced
by Fe/Mn implantation in ZnO, Al2O3, and MgO. These are attracting attention as dilute
magnetic oxides. In the case of ZnO, the formation of Fe3+–vacancy complexes is found todepend strongly on the implanted dose and to be faster and more efficient at higher
temperatures. The results at these temperatures suggest the mobility of the Zn vacancy,- 332 -

together with vacancy trapping at the substitutional Mn/Fe impurities are responsible for theformation of Fe–VZn complexes. These experiments were carried out at CERN-ISOLDE and
HIMAC.
The detection system for 57Mn implantation Mössbauer studies was improved by using ananticoincidence method where a thin plastic scintillation counter was set between the detector
and a sample in order to reject the β-rays from 57Mn. The Mössbauer spectrum with sufficientsignal-to-noise (S/N) ratio that is about 20 times higher than that in previous measurements
was successfully obtained.

Head
Masahiko IWASAKIMembers
Katsuhiko ISHIDA
Kenta ITAHASHI
Yoshio KOBAYASHI
Teiichiro MATSUZAKI
Hiroaki OHNISHI
Haruhiko OUTA
Fuminori SAKUMA
Isao WATANABE
Special Postdoctoral Researchers
Masami IIO
Kazuki OHISHI
Foreign Postdoctoral Researcher
Risdiana
Special Contract Researchers
Kyo TSUKADA
Contract Researchers
Yasuyuki ISHII
Takayuki KAWAMATA
Takahisa KOIKE
Katsuya MIZUNO
Takao SUZUKI
Dai TOMONO
Koji YOKOYAMA- 333 -

Visiting Scientists
Tadashi ADACHI (Grad. Sch. Eng., Tohoku Univ.)
Jun AKIMITSU (Coll. Sci. Eng., Aoyama Gakuin Univ.)
Shingo ARAKI (Grad. Sch. Sci., Osaka Univ.)
Kunio AWAGA (Grad. Sch. Sci., Nagoya Univ.)
Pavel BAKULE (RAL, UK)
George BEER (Univ. of Victoria, Canada)HyoungChan BHANG (Seoul National Univ., Korea)
N. Ludmila BOGDANOVA (ITEP, Russia)
Catalina CURCEANU (INFN, Italy)
Prasad Tara DAS (SUNY Albany, USA)
Irwan DHARMAWAN (UNPAD, Indonesia)
Truong DUAN (Grad. Sch. Sci., Osaka Univ.)
Yasuaki EINAGA (Fac. Sci & Tech., Keio. Univ.)
Donald FLEMING (Univ. of British Columbia/TRIUMF)
Masaya ENOMOTO (Grad. Sch. Arts and Sci., Univ. of Tokyo)
Mark FAYFMAN (Kurchatov Inst., Russia)
Yutaka FUJII (Fac. Eng., Fukui Univ.)
Hiroyuki FUJIOKA (Grad. Sch. Sci., Kyoto Univ.)
Masaki FUJITA (IMR, Tohoku Univ.)
Hideto FUKAZAWA (Grad. Sch. Sci., Chiba Univ.)
Takayuki GOTO (Fac. Sci. & Tech., Sophia Univ.)
Makoto HAGIWARA (Fac. Eng. Design, Kyoto Inst. Tech.)Kazuo HAYAKAWA (Fac of Sci. & Tech., Shizuoka Inst. Sci. & Tech.)
Ryugo S. HAYANO (Grad. Sch. Sci., Univ. of Tokyo)
Wataru HIGEMOTO (Advanced Sci. Res. Center, JAEA)
Masahiro HIRANO (JST)
Kazuto HIRATA (NIMS)
Satoru HIRENZAKI (Fac. Sci., Nara Women’s Univ.)
Masahiko HIROI (Fac. Sci., Kagoshima Univ.)
Susumu IKEDA (IMSS, KEK)
Yutaka IKEDO (IMSS, KEK)
Rintaro INOUE (ICR, Kyoto Univ.)
Takayuki ISHIDA (Fac. Elect. Commu., Univ. Elect. Commu.)
Fumihiro ISHIKAWA (Grad. Sch. Sci. & Tech., Niigata Univ.)
Shigeru ISHIMOTO (IPNS, KEK)
Tomoichi ISHIWATARI (SMI, Austria)
Ryosuke KADONO (IMSS, KEK)
Yoichi KAMIHARA (JST)Toshiji KANAYA (ICR, Kyoto Univ.)
Motomi KATADA (Grad. Sch. Sci. & Eng., Tokyo Met. Univ.)- 334 -

Mineo KATO (IMSS, KEK)
Roland KAWAKAMI (UC Riverside, USA)
Naritoshi KAWAMURA (IMSS, KEK)
Seiko KAWAMURA (J-PARC, JAEA)
Hikomitsu KIKUCHI (Grad. Sch. Eng., Univ. of Fukui)
Jungho KIM (KRISS, Korea)
Yasushi KINO (Fac. Sci., Tohoku Univ.)
Akihiro KODA (IMSS, KEK)
Yoh KOHORI (Fac. Sci., Chiba Univ.)
Yoji KOIKE (Grad. Sch. Eng., Tohoku Univ.)
Norimichi KOJIMA (Grad. Sch. Arts and Sci., Univ of Tokyo)
Kenya KUBO (Coll. Liberal Arts, ICU)
Yoshitaka KUNO (Grad. Sch. Sci., Osaka Univ.)
Takuya KURAHASHI (IMS)
Haruhiko KUROE (Fac. Sci. & Tech., Sophia Univ.)
Guido LANGOUCHE (Univ. of Leuven, Belgium)
Chow LEE (UCF, USA)
Shunsuke MAKIMURA (IMSS, KEK)
Goro MARUTA (Grad. Sch. Sci., Hokkaido Univ.)
Yasuyuki MTSUDA (Grad. Sch. Arts and Sci., Univ of Tokyo)
Satoru MATSUISHI (FCRC, Tokyo Tech.)
Yasuhiro MIYAKE (IMSS, KEK)
Hitoshi MIYASAKA (Grad. Sch. Sci., Tohoku Univ.)
Jun MIYAZAKI (Fac. Sci. Div., Nihon Univ.)
Soichiro MIZUSAKI (Coll.Sci. & Eng., Aoyama Gakuin Univ.)
Tomoyuki MOCHIDA (Grad. Sch. Sci., Kobe Univ.)
Kazuhiko MUKAI (Toyota Central R&D Labs.)
Yujiro NAGATA (Coll. Sci. Eng., Aoyama Gakuin Univ.)
Takashi NAGATOMO (Coll. Liberal Arts, ICU)
Hiroyuki NAKAMURA (Grad. Sch. Eng., Kyoto Univ.)
Jin NAKAMURA (Fac. Elect. Commu., Univ. Elect. Commu.)
Kazutaka NAKAHARA (Univ. of Maryland. USA)
Satoshi NAKAMURA (Grad. Sch. Sci., Tohoku Univ.)
Takashi NAKAMURA (Grad. Sch. Sci. & Eng., Tokyo Tech.)Takayoshi NAKAMURA (RIES, Hokkaido Univ.)
Takehito NAKANO (Grad. Sch. Sci., Osaka Univ.)
Saburou NASU (Grad, Sch. Eng. & Sci., Osaka Univ.)
Kazuhiko NINOMIYA (Advanced Sci. Res. Center, JAEA)
Nobuhiko NISHIDA (Fac. Sci., Tokyo Tech.)
Yoichi NISHIWAKI (Sch. Medi., TWMU)
Kusuo NISHIYAMA (IMSS, KEK)

- 335 -

Hiroshi NOZAKI (Toyota Central R&D Labs.)
Yasuo NOZUE (Grad. Sch. Sci., Osaka Univ.)
Agung NUGROHO (ITB, Indonesia)
Masaaki OHBA (Grad. Sch. Eng., Kyoto Univ.)
Yoshitaka OHKUBO (KURRI, Kyoto Univ.)
Susumu OHYA (Fac. Sci., Niigata Univ.)
Shinji OKADA (INFN, Italy)
Vassili PEREVOZCHIKO (VNIEF, Russia)
Leonid PONOMAREV (Kurchatov Institute, Russia)
Francis PRATT (RAL, UK)
Shin-ichi SAKAMOTO (J-PARC, JAEA)
Naohito SAITO (IPNS, KEK)
Kazuhiko SATO (Grad. Sch. Sci. & Eng., Saitama Univ.)
Masaharu SATO (Grad. Sch. Sci., Univ.of Tokyo)
Ralph SCHEICHER (Michigan Tech. Univ., USA)
Ryoichi SEKI (California State Univ. , Northridge, USA)
Kouichirou SHIMOMURA (IMSS, KEK)
Ichiro SHIRAKI (Grad. Sch. Medi. & Eng. Sci., Univ. of Yamanashi)
Vyacheslav STORCHAK (VNIIEF, Russia)
Patrick STRASSER (IMSS, KEK)
Hiroyuki SUGAI (Advanced Sci. Res. Center, JAEA)
Jun SUGIYAMA (Toyota Central R&D Labs.)
Ken SUZUKI (SMI, Austria)
Haruhiko SUZUKI (Grad. Sch. Nat. Sic. & Tech., Kanazawa Univ.)
Hiroyuki SUZUKI (NIMS)
Soh SUZUKI (CRC, KEK)
Takatoshi SUZUKI (Grad. Sch. Sci., Univ.of Tokyo)
Yoshikazu TABATA (Grad, Sch. Eng. & Sci., Kyoto Univ.)
Shigeru TAKAGI (Grad, Sch. Sci., Tohoku Univ.)
Kazuyuki TAKAI (Grad. Sch. Sci. & Eng., Tokyo Tech.)
Keiji TAKEDA (ISSP, Univ. of Tokyo)
Nao TAKESHITA (NeRI, AIST)
Hiroyuki TAKEYA (NIMS)
Yoichi TANABE (WPI, Tohoku Univ.)
Manobu TANAKA (IPNS, KEK)
Akihiro TANIGUCHI (KURRI, Kyoto Univ.)
Harry TOM (UC Riverside, USA)
Eiko TORIKAI (Grad. Sch. Medi. & Eng. Sci., Univ. of Yamanashi)
Akihisa TOYODA (IPNS, KEK)
Satoshi TSUTSUI (JASRI)
Kazuo UEDA (ISSP, Univ. of Tokyo)- 336 -

Yun XUE (Grad. Sch. Nat. Sic. & Tech., Kanazawa Univ.)
Eiichi YAGI (Fac. Sci. & Eng., Waseda Univ.)
Kazuyoshi YAMADA (IMR, Tohoku Univ.)
Yasuhiro YAMADA (Fac. Sci., Tokyo Univ. of Sci.)
Yutaka YOSHIDA (Fac of Sci. & Tech., Shizuoka Inst. Sci. & Tech.)
Arkady YUKHINCHUK (VNIIEF, Russia)
Johann ZMESKAL (SMI, Austria)
Visiting Technician
Shinji KAI (Tanaka Kikinzoku Kogyo K.K.)
Kunihiro SHIMA (Tanaka Kikinzoku Kogyo K.K.)
Research Consultants
Yoshinori AKAISHI
Masayasu KAMIMURA
Atsuko ITO
Toshimitsu YAMAZAKI
Students
Junior Reserch Associates
Yuya FUJIWARA (Grad. Sch. Sci., Univ. of Tokyo)
Toshihiko HIRAIWA (Grad. Sch. Sci., Kyoto Univ.)
Satoshi ITOH (Grad. Sch. Sci., Univ. of Tokyo)
InternMakoto TOKUDA (Grad. Sch. Sci. & Eng., Tokyo Tech.)Student Trainees
Takashi AKAHORI (Grad. Sch.Sci. & Eng., Shizuoka Inst. Sci. & Tech.)
Yuki AKIYAMA (Grad. Sch.Sci. & Eng., Shizuoka Inst. Sci. & Tech.)
Mika DOIZOE (Grad. Sch. Sci., Tokyo Univ. Sci.)
Shun ENOMOTO (Grad, Sch. Sci., Osaka Univ.)
Jafar ESMAILI (Isfahan Univ. Tech., Iran)
Yusuke GOTO (Fac. Sci., Univ. of Tokyo)
Ryuta HANAZAWA (Grad. Sch. Sci. & Eng., Shizuoka Inst. Sci. & Tech.)
Masatoshi HIRAISHI (Sch. High Enegy Acce. Sci.,Sokendai)
Toru HISAMATSU (Grad. Sch. Sci. & Eng., Kagoshima Univ.)
Tadashi HASHIMOTO (Grad. Sch. Sci., Univ. of Tokyo)
Masahiro ICHINO (Grad. Sch.Sci. & Eng., Shizuoka Inst. Sci. & Tech.)
Naho IINUMA (Grad. Sch. Sci., Tokyo Univ. Sci.)
Asae ITO (Fac. Sci., Tokyo Univ. Sci.)- 337 -Naoki KASE (Grad. Sch. Sci.& Eng., Aoyama Gakuin Univ.)
Yu KAWAHARA (Grad. Sch. Sci., Tokyo Univ. Sci.)
Takumi KOBAYASHI (Grad. Sch. Sci., Univ. of Tokyo)
Naoyuki KONNO (Grad. Sch. Sci., Tokyo Univ. Sci.)
Hiroshi KOU (Grad. Sch. Sci. & Eng., Tokyo Tech.)
Hiroto KUMABE (Grad. Sch.Sci. & Eng., Shizuoka Inst. Sci. & Tech.)
Yoko MANABE (Grad. Sch. Sci. & Eng., Saitama Univ.)
Masanori MIYAZAKI (Sch. Phys. Sci.,Sokendai)
Kiichi MIYAZAWA (Grad. Sch. Indus. Sci. & Tech., Tokyo Univ. Sci.)
Saori NAKAJIMA (Grad. Sch. Sci. & Tech., Sophia Univ.)
Takahiro NISHI (Fac. Sci., Univ. of Tokyo)
Kumiko OKAMURA (Fac. Sci., Tokyo Univ. Sci.)
ROGER PINK (SUNY at Albany, USA)
Manami SATAKE (Grad. Sch. Sci. & Eng., Tokyo Tech.)
Ryuichi SUEHIRO (Grad. Sch. Sci., Osaka Univ.)
Kensuke SUZUKI (Grad. Sch. Eng., Tohoku Univ.)
Tomonori TAKAHASHI (Grad. Sch. Sci., Univ. of Tokyo)
Arisa TANIGUCHI (Grad. Sch. Sci. & Eng., Saitama Univ.)
Hideyuki TATSUNO (Grad. Sch. Sci., Univ. of Tokyo)
Koichi TODOROKI (Grad. Sch. Sci., Univ. of Tokyo)
Maai UCHIKAWA (Grad. Sch. Sci., Univ. of Tokyo)
Shin UEGAKI (Grad. Sch. Sci., Tokyo Univ. Sci.)
Ryo USUI (Fac. Sci., Tokyo Univ. Sci.)
Heejoong YIM (Seoul National Univ., Korea)
Secretaries
Yoko FUJITA
Junko SATO

- 338 -

㪪㫌㪹㩷㪥㫌㪺㫃㪼㪸㫉㩷㪪㫐㫊㫋㪼㫄㩷㪩㪼㫊㪼㪸㫉㪺㪿㩷㪛㫀㫍㫀㫊㫀㫆㫅㩷㪩㪠㪢㪜㪥㪄㪙㪥㪣㩷㪩㪼㫊㪼㪸㫉㪺㪿㩷㪚㪼㫅㫋㪼㫉㩷 㩷 㩷 㩷㪫㪿㪼㫆㫉㫐㩷㪞㫉㫆㫌㫇㩷
1. Abstract
The RIKEN BNL Research Center (RBRC) was established in April 1997 at Brookhaven
National Laboratory in New York, USA. The Center is dedicated to study of strong interactions,
including hard QCD/spin physics, lattice QCD and RHIC physics through nurturing of a newgeneration of young physicists. The Theory Group activities are closely and intimately related tothose of the Nuclear Theory, High Energy Theory and Lattice Gauge Theory Groups at BNL.
The RBRC theory group carries out research in three areas: numerical lattice QCD, perturbative
QCD and phenomenological QCD. It pioneered the use of the domain-wall fermion method inlattice QCD and has investigated various aspects of hadron physics including the calculation ofneutral Kaon CP-violations that is relevant for checking the Cabibbo-Kobayashi-Maskawa theory.
The perturbative QCD effort has developed various new methods required for studying hadronstructures, especially in spin physics research. The group has pioneered phenomenological QCD
researches of color superconductivity, isospin density, and small-x phenomena in extreme hadronicmatters.
2. Major Research Subjects(1) Perturbative QCD(2) Lattice QCD numerical research(3) Phenomenological QCD
3. Summary of Research Activity
The RIKENBNL Research Center (RBRC) was established in 1997 to support the RIKEN
activities at RHIC in BNL, and also to promote theoretical studies related to RHIC, i.e. theories ofstrong interaction. The center’s first director was T. D. Lee (Columbia University), and in October
2003, the former director of BNL, N. P. Samios, succeeded to the post of director. H. En'yo, Chief
scientist of RIKEN in Wako, is also associate director of RBRC. The center consists of a theory
group lead by L. Mclerran (BNL) and an experimental group lead by Y. Akiba of RIKEN,
currently resident at BNL.
Research in the RBRC theory group focuses on a wide variety of phenomena caused by thestrong interaction, one of the four fundamental interactions in nature. The strong interaction is
described theoretically by Quantum Chromodynamics (QCD), and the research projects in the
RBRC theory group aim to elucidate various phenomena brought about by the strong interaction
from the principles of QCD. Major subjects of our research include studies (a) based on lattice
QCD, (b) on spin physics based on perturbative QCD, and (c) on QCD in extreme conditions suchas high temperature, high density or high energy. RBRC offers RHIC Physics Fellowships,
allowing joint appointments with universities. These Fellowships enable a talented researcher tomaintain a tenure track position at his/her university as well as a Fellow position at RBRC for acertain period of time. This system was established in order to increase the research potential of
RBRC and to disseminate its research activities and results. At present, RBRC has cooperative
agreements with Arizona State University, the City University of New York, Iowa State University,- 339 -

Purdue University, Pennsylvania State University, the State University of New York at Stony
Brook, Texas A&M University, the University of Tsukuba, as well as with BNL and with
Lawrence Berkeley National Laboratory.
(1) Lattice QCDQCDOC (QCD on chip), a second-generation lattice-QCD computer, was developed in thecollaboration amongst the RBRC group, Columbia University and IBM. Three units of such amachine with 10 teraflops computing power are in operation since 2005; two in BNL (RBRC andDOE) and one in Edinburgh (UK-QCD), and formed a world-wide strong collaboration for thelattice QCD studies. Such computing power enables us to perform precise calculations with 3
quark flavors with proper handling on the chiral symmetry breaking. Several projects are ongoing:flavor physics for Kaon and B-meson, electro-magnetic properties of hadrons, proton decay, thenuclear force, nucleon form factors which relates to the proton spin problem, and QCD
thermodynamics in finite temperature/density systems as is produced in RHIC heavy-ion collisions.
R and D for a next generation RBRC lattice supercomputer, QCDCQ is finalized. The initial 1/2
rack QCDCQ will be installed in fall 2010, and larger volume machines are under considerationof installation in 2011.
(2) Perturbative QCD and spin physics
The ongoing RHIC spin experiments have motivated much of the parallel theoreticaldevelopments at RBRC. In the area of transverse spin physics, novel predictions have beenobtained for the single transverse-spin asymmetry in open charm production in pp collisions at
RHIC. This asymmetry probes three gluon correlations in polarized proton. In addition, radiative
QCD corrections to single-spin observables were investigated, providing the relevant evolution
equations. Further work focused on hyperon production at RHIC, and on azimuthal asymmetries
in the Drell-Yan process.
(3) Phenomenological QCD -- QCD under extreme conditions -To establish a detailed picture of relativistic heavy ion collisions, QCD-based theoretical
approaches are in progress. Especially the idea of “color glass condensation (CGC)” can be a key
to understand the initial condition of the heavy ion collision. Other phenomenologicalapproaches are in progress to understand the characteristics of strongly interacting quark gluon
plasma. A recent effort has been initiated to understand heavy ion elliptic flow in term s of viscoushydrodynamics. A new finite temperature effective field theory is being developed for thestrongly interacting quark gluon plasma to explain the suppression of sheer viscosity in theregion of the phase transition.

Group Leader
Larry McLERRAN
Deputy Group Leader
AnthonyJ. BALTZ- 340 -

Members
Yasumichi AOKI *1
Denes MOLNAR *2
Kirill TUCHIN *2
Rainer FRIES *2
Tomomi ISHIKAWA *3
Feng YUAN *2
Toru KOJO *4
Peter PETRECZKY *2
Taku IZUBUCHI *1
Sinya AOKI *5
Derek TEANEY *2
Adrian DUMITRU *2
Cecilia LUNARDINI *2
Anna STASTO *2
Zhongbo Kang *3
Visiting Members
Miklos GYULASSY (Columbia Univ., USA)
RobertL. JAFFE (Massachusetts Inst. Technol., USA)
Robert MAWHINNEY (Columbia Univ., USA)
Edward SHURYAK (State Univ. New York, Stony Brook, USA)
Testufumi HIRANO (U. Tokyo)
Shigemi OHTA (KEK)
Secretarial Staff
Doris RUEGER (Secretary to Director N. P. Samios)
Pamela ESPOSITO (Theory Group Secretary)
Taeko ITO (Assistant to Account Manager for Administration)
Susan FOSTER (Experimental Group Secretary)
Administrative Staff / RIKEN Japan
Minoru Fujiki, Deputy Director, Nishina Center Research Promotion Office
Emiko ADACHI (RBRC Account Manager for Administration)
Keiko SUSUKI (Japan)*1 RIKEN BNL Fellow *2 RHIC Physics Fellow,*3 Research Associate, *4 Special Postdoctoral Researcher,*5 RHIC visiting Fellow- 341 -

㪪㫌㪹㩷㪥㫌㪺㫃㪼㪸㫉㩷㪪㫐㫊㫋㪼㫄㩷㪩㪼㫊㪼㪸㫉㪺㪿㩷㪛㫀㫍㫀㫊㫀㫆㫅㩷㪩㪠㪢㪜㪥㪄㪙㪥㪣㩷㪩㪼㫊㪼㪸㫉㪺㪿㩷㪚㪼㫅㫋㪼㫉㩷 㩷㪜㫏㫇㪼㫉㫀㫄㪼㫅㫋㪸㫃㩷㪞㫉㫆㫌㫇㩷

1. Abstract
RIKEN BNL Research Center (RBRC) Experimental Group studies the strong interactions(QCD) using RHIC accelerator at Brookhaven National Laboratory, the world first heavy ion
collider and polarized p+p collider. We have three major activities: Spin Physics at RHIC,
Heavy ion physics at RHIC, and detector upgrades of PHENIX experiment at RHIC. We study
the spin structure of the proton using the polarized proton-proton collisions at RHIC. This
program has been promoted by RIKEN’s leadership. The first focus of the research is tomeasure the gluon spin contribution to the proton spin. Our recent data analysis has shown thatthe proton spin carried by the gluons is small, which is a very striking finding beyond our
expectations. The aim of Heavy ion physics at RHIC is to re-create Quark Gluon Plasma(QGP), the state of Universe just after the Big Bang. Two important discoveries, jet quenchingeffect and strong elliptic flows, have established that new state of dense matter is indeed
produced in heavy ion collisions at RHIC. We are proceeding to understand the nature of thematter. Recently, we have measured direct photons in Au+Au collisions for 1<pT<3 GeV/c ,where thermal radiation from hot QGP is expected to dominate. The comparison between thedata and theory calculations indicates that the initial temperature of 300 MeV to 600 MeV isachieved. These values are well above the transition temperature to QGP, which is calculated tobe approximately 170 MeV by lattice QCD calculations.
We has major roles in detector upgrades of PHENIX experiment, namely, the silicon vertex
tracker (VTX) and muon trigger upgrades.
2. Major Research Subjects(1) Experimental Studies of the Spin Structure of the Nucleon(2) Study of Quark-Gluon Plasma at RHIC
(3) PHENIX detector upgrades
3. Summary of Research Activity
The RIKEN-BNL Research Center was established in 1997 to support the RIKEN activities
at RHIC in BNL, and also to promote theoretical studies related to RHIC, i.e. theories of strong
interaction. The center’s first director was T. D. Lee (Columbia University), and in October
2003, the former director of BNL, N.P. Samios, succeeded to the post of the director. The
center consists of a theory group lead by L. Mclerran (BNL) and an experimental group leadby Y. Akiba, a vice chief scientist of RIKEN in Wako.
We study the strong interactions (QCD) using the RHIC accelerator at Brookhaven National
Laboratory, the world first heavy ion collider and polarized p+p collider. We have three major
activities: Spin Physics at RHIC, Heavy ion physics at RHIC, and detector upgrades of
PHENIX experiment.
(1) Experimental study of spin structure of proton using RHIC polarized proton collider
How is the spin of proton formed with 3 quarks and gluons? This is a very fundamental
question in Quantum Chromodynamics (QCD), the theory of the strong nuclear forces. The- 342 -

RHIC Spin Project has been established as an international collaboration between RIKEN and
Brookhaven National Laboratory (BNL) to solve this problem by colliding two polarized
protons for the first time in history. This project also has extended the physics capabilities of
RHIC.
The first goal of the RHIC spin physics program is to elucidate a contribution of the gluon
spin in the proton spin. We have measured double-helicity asymmetries of neutral pions tostudy gluon polarization in proton. The most recent data from 2006 run have shown that thegluon polarization in the proton is small, and only about half of proton spin can be accounted
by gluon spin in the measured region of gluon momentum in proton. The remaining part must
be carried by gluons in lower momentum region where the measurement is not sensitive,
and/or reside in the orbital-angular momentum of quarks and gluons.
To finalize the smallness of the gluon-spin contribution, we need to measure double helicitiyasymmetry in direct photon production. This process is dominated by a single and the simplest
process, gluon Compton scattering, in perturbative QCD, and is the golden channel todetermine the gluon density and the gluon polarization in the proton. We published a paper on
direct photon cross section in p+p collisions at RHIC. Preliminary results on double-helicity
asymmetry of direct photon from the 2006 run have been obtained.
We have also accumulating transversely-polarized proton collision data to measure single
transverse-spin asymmetries of processes which are predicted to be sensitive to theorbital-angular momentum of quarks and gluons. In 2006 and 2008, PHENIX recorded 2.7/pb
and 4.5/pb, respectively, of transversely-polarized proton collisions data at 200 GeV toinvestigate single transverse-spin asymmetries. Several transverse spin analysis of these highstatistics data are on going.
The 2009 run of RHIC is a major spin run. We had the first 500 GeV p+p run and a long
p+p run at 200 GeV. The main purpose of the 500 GeV run is to measure anit-quark
polarization from the single longitudinal asymmetry A_L in the W boson production. The 500
GeV part of RUN9 is an engineering run. The polarization is lower (~40%) than the 200 GeV
run and the luminosity in the 5 weeks of data taking period is rather limited, at about 14/pb
recorded in PHENIX. Yet we have observed the first signal of W->e decays in p+p collisions
in PHENIX central arm. The group is working on the cross section analysis and the A_L
measurement analysis. In the 200 GeV part of RUN9, PHENIX recorded approximately twice
as much longitudinal polarized p+p data as the 2006 RUN.
In addition to the study of polarized p+p collisions at RHIC, we study quark fragmentation
function. With collaboration with the BELLE experiment at High Energy Accelerator Research
Organization (KEK), we discovered that the spin direction of a quark can be determined fromits hadronic fragments. Precise data of the quark fragmentation function can be used tounderstand the cross sections and the spin dependences of particle production in polarized p+p
collisions at RHIC. We continue the study of the quark fragmentation function at BELLE.
(2) Experimental study of Quark-Gluon Plasma using RHIC heavy-ion collider
The goal of high energy heavy ion physics at RHIC is study of QCD in extreme conditions
i.e. at very high temperature and at very high energy density. Experimental results from RHIC
have established that dense partonic matter is formed in Au+Au collisions at RHIC. The matteris very dense and opaque, and it has almost no viscosity and behaves like a perfect fluid. These
conclusions are primarily based on the following two discoveries:• Strong suppression of high transverse momentum hadrons in central Au+Au collisions- 343 -

(jet quenching)• Strong elliptic flow
The focus of the research in heavy ion physics at RHIC is now to investigate the propertiesof the matter. RBRC have played the leading roles in some of the most important results fromPHENIX in the study of the matter properties. These include (1) measurements of heavy quark
production from the single electrons from heavy flavor decay (2) measurements of J/Psi
production (3) measurements of di-electron continuum and (4) measurements of direct
photons.
The most important recent result is the measurement of direct photons for 1<pT<5 GeV/c in
p+p and Au+Au through their internal conversion to e+e- pairs.If the dense partonic matter
formed at RHIC is thermalized, it should emit thermal photons. Observation of thermal photon
is direct evidence of early thermalization, and we can determine the initial temperature of thematter. It is predicted that thermal photons from QGP phase is the dominant source of direct
photons for 1<pT<3 GeV/c at the RHIC energy. We measured the direct photon in this pT
region from measurements of quasi-real virtual photons that decays into low-mass e+e- pairs.
Strong enhancement of direct photon yield in Au+Au over the scaled p+p data has been
observed. Several hydrodynamical models can reproduce the central Au+A data within a factorof two. These models assume formation of a hot system with initial temperature of Tinit = 300
MeV to 600 MeV. This is the first measurement of initial temperature of quark gluon plasma
formed at RHIC.
(3) PHENIX detector upgrade
The group has major roles in several PHENIX detector upgrades, namely, the silicon vertex
tracker (VTX) and muon trigger upgrades.
VTX is 4 layers of silicon tracker, jointly funded by RIKEN and the US DOE. The inner twolayers are silicon pixel detectors and the outer two layers are silicon strip detectors. The
detector will be completed in 2010.
Muon trigger upgrades are needed for WÆ mu measurement at 500 GeV. New trigger
electronics (Muon Trigger FEE) have been installed in one of muon arms and they will becommissioned in the 2009 run. After the 2009 run, the rest of the Muon Trigger FEE will be
installed in PHENIX. Prototype o muon trigger detectors using MRPC technology have been
installed for test during the 2009 run.

Group Leader
Yasuyuki AKIBA

Deputy Group Leader
Abhay DESHPANDE

Members
Yuji GOTO
Itaru NAKAGAWA
Takashi ICHIHARA- 344 -

Atsushi TAKETANI
Yasushi WATANABE
Satoru YOKKAICHI
Kensuke OKADA *1
Ralf-Christian SEIDL *1
Stefan BATHE *1
David KAWALL *2
Kieran BOYLE *3
Manabu Togawa *4
Jun TAMURA (T.I.Tech)*5
Yorito YAMAGUCHI (CNS-U-Tokyo)*5
Misaki OUCHIDA (Hiroshima Univ)*5
Kenichi KARATSU (Kyoto Univ)*5
Yoki ARAMAKI (CNS-U-Tokyo)*5
Akihisa TAKAHARA (CNS-U-Tokyo)*5
Miki KASAI (Rikkyo)*5

Visiting Members
Naohito SAITO (KEK)
Zheng LEE (BNL)
Kiyoshi TANIDA (Kyoto Univ.)
Akio OGAWA (BNL)
Masahiro OKAMURA (BNL)
Rachid NOUICER (BNL)
Kotaro KONDO (T.I.Tech)*8
Kohei SHOJI (Kyoto Univ.)*7
Seishi DAIRAKU (Kyoto Univ.)*7
Katsuro NAKAMURA (Kyoto Univ.)*6
Takeshi KANESUE (Kyusyu Univ.)*7*1RIKEN BNL Fellow, *2 RHIC Physics Fellow,*3 Research Associate, *4 Special Postdoctoral Researcher,*5 Junior Research Associate, *6 JSPS Student, *7 Student trainee*8 JSPS Postdoc- 345 -

㪩㪠㪙㪝㩷㪩㪼㫊㪼㪸㫉㪺㪿㩷㪛㫀㫍㫀㫊㫀㫆㫅㩷㪟㪼㪸㫍㫐㩷㪠㫆㫅㩷㪥㫌㪺㫃㪼㪸㫉㩷㪧㪿㫐㫊㫀㪺㫊㩷㪣㪸㪹㫆㫉㪸㫋㫆㫉㫐㩷
1 Abstract
With fast RI beams provided by the RIBF cyclotron complex and the in-flight RI separators RIPS
and BigRIPS, we study exotic behavior of nuclei far from the stability line, explosive nuclear
burning in stars and early universe, and nuclear reactions related to solar neutrino production. For
that purpose, we develop various experimental methods utilizing intermediate-energy inelastic
scattering including Coulomb excitation, Coulomb dissociation, transfer- andfragmentation-reactions coupled with gamma- and particle-decay measurements. We perform
also study of the three-nucleon forces by precise measurements of elastic scattering and breakup
reactions of few-nucleon systems. A new laser-spectroscopy technique for exotic nuclei is also
developed. Technical developments of radiation measurements such as semiconductor detectors
and scintillation detectors, data processing methods, and construction of experimental equipment
are also made. Theoretical studies on nuclear structure and nuclear reaction are performed.
2 Major Research Subjects(1) Spectroscopy of unstable nuclei with direct reactions(2) Study of astrophysical nuclear reactions with fast beams of unstable nuclei(3) Three nucleon forces studied by intermediate-energy p+d scattering(4) Development of high performance radiation detector systems(5) Development of laser spectroscopy for studying unstable nuclei(6) Theoretical studies on nuclear structure and nuclear reactions
3 Summary of Research Activity
3.1. Spectroscopy using direct reactions with γ-ray measurements
The evolution of shell structure, development of collectivity, and possible decoupling of
proton- and neutron-motion in neutron- and proton-rich nuclei are studied by direct reactions with
γ-ray measurements. In order to extract different quantities, various reactions were used such as
proton inelastic scattering, Coulomb excitation, nucleon removal reactions.
(1) 32Ne, 32Mg, 34Si – in island of inversion around N=20
In order to clarify the nature of the “islands of inversion” around N=20, the structures of low-lying
levels in 32Mg and 34Si were studied through the proton inelastic scattering. The 4+ state as well as
several other excited states were found in 32Mg. The location of the 3- state indicatesdisappearance of the sd-pf shell gap in 32Mg. The anomalously hindered B(E2) value for the 0+-2+transition in 34Si was compared with the neutron-transition quadrupole matrix element extracted
from the 34Si(p,p’) result. The very neutron rich nucleus 32Ne was studied by the Coulomb
excitation at the new facility of RIBF. The result indicates that this nucleus is in the island of
inversion.
(2) 17,18C – new method with transverse momentum measurement
The spins and parities of the low-lying levels in 17C and 18C were determined by the transverse
momentum distributions of fragments produced in the one neutron removal reactions of 18C and19
C beams with a hydrogen target. The final states were identified by detecting their de-excitation
γ-rays. The result indicates the usefulness of the transverse-momentum associated with proton
induced nucleon removal processes for the spin-assignment with the help of new approach for thereaction process, i.e. CDCC.
(3) 62,64Cr – behavior of neutron-rich nuclei around N=40
The development of deformation in 62Cr was observed by the large deformation length and the- 346 -

4+-2+ energy ratio obtained in the proton inelastic scattering experiment performed at RIPS. Thisconfirms the new region of deformation emerging in the neutron-rich N~40 region despite of thefact that N=40 is a magic number for the harmonic oscillator potential(4) 20Mg – role of four protons around the 16O core
The collectivity of the proton-rich nucleus 20Mg was studied by the Coulomb excitation. The
B(E2) value for the 2+ excitation was compared with that for the mirror nucleus 20O. The large
ratio between the neutron- and proton-matrix elements is consistent with the known corepolarization effect induced by the valence nucleons, showing that the anomalous decoupling
phenomena observed in 16O is not observed in 20O and 20Mg.
3.2. Spectroscopy of unbound states using breakup and other reactions(1) Halo structure of 31Ne
The structure of the very neutron-rich nucleus 31Ne was studied at RIBF via Coulomb breakup
reaction. The obtained inclusive cross section shows an abnormal enhancement, which indicatesthe neutron halo structure in this nucleus.
(1) Invariant mass spectroscopy of nuclei in the vicinity of the neutron drip line(a) Study of unbound states in 13Be and 14Be
The first 2+ state of 14Be at Ex=1.55 MeV was measured in the proton inelastic scattering. Fromthe cross section, deformation length was obtained, which shows a small value as compared withthat of 12Be. The unbound states in 13Be were identified at around Exx =0.5 MeV and 2 MeV in theinvariant mass spectrum observed in the one-neutron removal reaction. The former has a d-wave
property, while the latter is of p-wave nature which indicates obliteration of he N=8 shell gap.
(b) Invariant mass spectra were obtained by the breakup and inelastic scattering of 6He, 17C, and19
C on proton targets. New peaks were found for neutron-rich carbon isotopes.
(2)Invariant mass spectroscopy of proton-rich nuclei
Coulomb dissociation of proton-rich nuclei 23Al, 27P, and 31Cl on 208Pb were measured to obtain
the radiative proton capture cross section of 22Mg, 26Si, and 30S. These reactions are relevant in
the explosive nucleosynthesis in novae and X-ray bursts and thus their cross sections areindispensable for the astrophysical network calculation.
(3) Missing mass spectroscopy of very neutron-rich light nuclei
Experimental search for the 7H system with largest N/Z ratio ever known was performed in thed(8He,3He)7H reaction using missing mass method. The excitation spectrum shows the peculiarity
at ~ 2 MeV that can not be reproduced by a reasonable phase space distributions and might
indicate the existence of the 7H state at low excitation energy. Simultaneously, the strong peaks
that corresponds to 7He and 11Li ground states were observed in the d(8He,t) and d(12Be,3He)
reaction channels.
3.3. Experimental studies on the three nucleon forces(1) Necessity of the three-nucleon-force is shown to reproduce the deuteron-proton elastic
scattering cross section. To further investigate the three-nucleon-force, spin transfer coefficientsfor deuteron-proton breakup reactions were measured. The study has been extended using the
new RIBF facility to higher energies at 250MeV/nucleon, where the effect of thethree-nucleon-force is expected to be more pronounced.
(2) We tested Bell’s inequality in the proton-neutron system by measuring the spin-correlation
between the proton-neutron pair in 1S0-state which was produced by the 2H(d,pn) reaction.
- 347 -

Among many other experiments performed thus far, this is the first case using the proton andneutron pair.
3.4. “OROCHI” (Optical RI atom Observation in Condensed Helium as Ion-catcher)development
A novel nuclear laser spectroscopy technique for exotic nuclei trapped in superfluid helium,
named as OROCHI (Optical RI-atom Observation in Condensed Helium as Ion-catcher), is being
developed. We have carried out high precision measurement of Zeeman and hyperfine splittingof 85,87Rb and 133Cs atoms in superfluid helium, and successfully demonstrated that the nuclear
spins and moments of unknown nuclei can be deduced by comparing their Zeeman and hyperfine
splitting energies with those of known nuclei. We have also succeeded in optical pumping of
non-alkali atoms such as Ag, which opens the door to the versatility of the OROCHI method. We
are now ready to measure unknown spins and moments of exotic nuclei.
3.5. SCRIT development
SCRIT (Self-Confining RI Target) is a novel experimental scheme to enable the study of theinternal structure of exotic nuclei by electron scattering. We have shown the feasibility of thisscheme by using a prototype installed at the electron storage ring, KSR, of Kyoto University.
Aiming at the future experiment using SCRIT with unstable nuclear beams, the construction of
the SR2 (SCRIT-equipped RIKEN Storage RING) has been started at RIBF. We have achieved
the accumulation of the electron beam with the energy of 700MeV.
3.6. SAMURAISAMURAI (Superconducting Analyzer for Multi-particle from Radio Isotope Beams) is alarge-acceptance multi-particle spectrometer we will construct at RIBF. Its major part is of alarge-gap superconducting magnet with 7 Tm of bending power. SAMURAI enables momentum
analysis of heavy projectile fragments and projectile-rapidity protons with large angular andmomentum acceptance. SAMURAI also affords projectile-rapidity neutron measurements withlarge angular acceptance in coincidence with heavy projectile fragments.
The construction budget has been approved, and is funded in four years from fiscal year 2008.
The budget covers the superconducting dipole magnet and most part of detectors for heavy ions,
neutrons, and protons. Our lab is, in particular, in charge of silicon strip detectors for protons andheavy ions and readout circuits requiring capability of broad dynamic range and high density
signal processing. Our lab also partly takes care of the total arrangements of the SAMURAI
collaboration group constituted by members from several institutes, each of which has unique
physics interest.
Detailed design of the superconducting dipole magnet has been almost complete. The magnet
construction in RIBF will start in the summer of 2010, and will complete early in 2011. The
detectors are constructed in parallel. It is planned that the first SAMURAI experiment isperformed in summer 2011.
3.7. Theoretical studies of nuclear physics
Studies on nuclear structure at finite temperature are in progress: A self-consistent formulation ofquasiparticle RPA including the effects of quantal and thermal fluctuations to study the propertiesof finite systems with pairing at finite temperature and angular momentum.

- 348 -

Head
Tohru MOTOBAYASHIMemberYukari MATSUO
Yoshiyuki YANAGISAWA
Nori AOI
Ken-ichiro YONEDA
Yasushi WATANABE
Toshimi SUDA
Akihisa KOHAMA

Contract Researchers
NguyenDinh DANG
Kimiko SEKIGUCHI(SAKAGUCHI)

Senior Visiting Scientists
Kengo OGAWA (Yamazaki Lab. In Riken)
Wolfgang MITTIG (GANIL)
Hisashi HORIUCHI (Osaka Univ.Nuclear Physics Center)
Hiroyuki SAKURAGI (Grad. Sch. of Sci., Osaka City Univ.)

Research Consultants
Yasuo AOKI (univ. of Tsukuba)
Hiroyuki MURAKAMI (Rikkyo Univ.)
Toshimitsu YAMAZAKI (Nishina Foundation)

Special Postdoctoral Researchers
Yasuhiro TOGANO (Rikkyo Univ.)

Junior Research Associates
Kenjiro MIKI (Univ. of Tokyo)
Masafumi MATSUSHITA (Rikkyo Univ.)

Nishina Fellow Ship
NguyenQuang HUNG (Hanoi Univ. of science)

International Program Associates
He WANG (Peking Univ., China)

Visiting Scientists
Mototsugu MIHARA (Osaka Univ.)- 349 -

Takuji IZUMIKAWA (Niigata Univ.)
Tomotsugu WAKASA (Kyushu Univ.)
Kyoichiro OZAWA (Univ. of Tokyo)
Didier BEAUMEL (Pris-XI Univ.)
Shinichiro FUJII (Kyushu Univ.)
Yasuo MIAKE (Tsukuba Univ.)
Mitsuo SAKAI (Univ. of Tokyo)
Peter MOLLER (Los Alamos)
Nasser KALANTAR (Univ. of Groningen)
Michael FAMIANO (Michigan State Univ.)
Kikuo KIMURA (Nagasaki Institute of Applied Science)
Kensaku MATSUTA (Osaka Univ.)
Yasuo WAKABAYASHI (Univ. of Tokyo)
Yosuke KONDO (Tokyo Institute of Technology)
Zoltan ELEKES (ATOMKI)
Gabor KALINKA (ATOMKI)
Takashi OHTSUBO (Niigata Univ.)
Jianjun HE (Chinese Academy of Science)
Takahiro KAWABATA (Kyoto Univ.)
Ben MOTTELSON (NORDITA)
Kazushige MAEDA (Tohoku Univ.)
Hiroshi SUZUKI (Tsukuba Univ.)
KevinInsik HAHN (Ewha Woman's Univ)
PeterVon BRENTANO (Univ. of Cologne)
Atsushi HATAKEYAMA (Tokyo Univ. of Agriculture and Technology )Yanlin YE (Peking Univ.)
Julien GIBELIN (CEAN)
Dorottya SOHLER (ATOMKI)
JunYoung MOON (Chung-Ang Univ.)
Yorick BLUMENFELD (Paris-XI Univ.)
Bo CEDERWALL (Royal Institute of Technology)
Takashi KIKUCHI (Nagaoka Univ. of Technology)
Tetsuro KOMATSUBARA (Tsukuba Univ.)
Hironobu ISIYAMA (KEK)
Rubens LICHTENTHALER (The Univ. of Sao Paulo)
Valdir GUIMARAES (The Univ. of Sao Paulo)
Jingbin LU
Johannes MESSCHENDORP
Akos HORVATH (Budapest)
Takeshi KOIKE (Tohoku Univ.)
Kimikazu SASA (Tsukuba Univ.)
Xiangzhou CAI (SINAP)
Alessandra GUGLIELMETTI (Univ. of Milano)- 350 -

Marco MAZZOCCO (Univ. of Padova)
Mauro ROMOLI (INFN)
Sunchan JEONG (KEK)
Betty TSANG (Michigan State Univ.)
Franck DELAUNAY (CEAN)
Andreas STOLZ (Michigan State Univ.)
Zhihong LI (China Institute of Atomic Energy)
Shoji SUZUKI (KEK)
Silvio CHERUBINI (Univ. of Catania)
MarcoLa COGNATA (Univ. of Catania)
Gianluca PIZZONE (Univ. of Catania)
YoungKwan KWON (Chung-Ang Univ.)
Ken-Ichi FUSHIMI (Tokushima Univ.)
Ichiro ARAI (Tsukuba Univ.)
Tadaaki TAMAE (Tohoku Univ.)
Jonathan PEARSON
Alan CHEN (McMaster Univ.)
Masatoshi ITOH (Tohoku Univ.)
Daniel BEMMERER
Adam KISS (Eotvos Lorand Univ.)
Georg BERG (Univ. of Notre Dame)
Henning ESBENSEN (Argonne National Laboratory)
Weiping LIU (China Institute of Atomic Energy)
Wei GUO
Patricia ROUSSEL-CHOMAZ (GANIL)
Chen LI (Inst. of Modern Physics, Chinese Academy of Sciences (IMP, CAS) )David HINDE (Australian National University)
Renju THOMAS
Mahananda DASGUPTA
Stefano ROMANO (Univ. of Catania)
Wendong TIAN (Chinese Academy of Science)
Tomokazu SUZUKI (Osaka Univ.)
Richard BOYD (Ohaio State Univ.)
Yang SUN (Shanghai Jiao Tong University)
NicolasDe SEREVILLE (IPN-Orsay )Alian COC (C.N.R.S)
David DEAN (Oak Ridge National Univ.)
Thomas PAPENBROCK (Univ. of Tennessee)
Alinka LEPINE (The Univ. of Sao Paulo)
Zhendong WU (China Institute of Atomic Energy)
Chengjian LIN (China Institute of Atomic Energy)
Takashi ABE (Univ. of Tokyo)
MarcoLa COMMARA (Univ. of Napoli)- 351 -

Claudio SPITALERI (Catania Univ.)
Livius TRACHE (Texas A&M Univ.)
Aurora TUMINO (Catania Univ.)
Alexander MURPHY (Univ. of Edinburgh)
Fairouz HAMMACHE (IPN-Orsay)
Philip WOODS (Univ. of Edinburgh)
Jiansong WANG (Inst. of Modern Physics, Chinese Academy of Sciences (IMP,
CAS) )
Hongwei WANG (SINAP)
Rudrajyoti PALIT (Tata Institute of Fundamental Research)
Bing GUO (China Institute of Atomic Energy)
Youbao WANG (China Institute of Atomic Energy)
Zhengguo HU (Chinese Academy of Science)
Meng WANG (Chinese Academy of Science)
Jingen CHEN (Chinese Academy of Science)
Nigel ORR (CEAN)
Roman GERNHAUSER (Technische Universität München、TUM)
Shengquan YAN (China Institute of Atomic Energy)
MarquesMiguel MORENO (CEAN)
Changbum MOON (Hoseo Univ.)
Remco ZEGERS (Michigan State Univ.)
Se-Hwan PARK (KAERI)David JENKINS (The Univ. of York)
Setepane GREVY (GANIL)
Lucia CACERES (GANIL)
F.A. BECK
Alexey KORSHENINNIKOV (Kurchatov Instutute)Masahiro NOTANI
Kazuyoshi KURITA (Rikkyo Univ.)
Naohito IWASA (Tohoku Univ.)
Yoshiteru SATO (Seoul National Univ.)
Takayuki YAMAGUCHI (Saitama Univ.)
Yutaka WATANABE (KEK)
Chongcheoul YUN (Jyungang Univ.)
Tadanori MINAMISONO (Fukui University of Tech.)
Yasuki NAGAI (JAEA)
Hiroyuki OKAMURA (RCNP Osaka Univ.)
Kichiji HATANAKA (Osaka Univ.)
Yoshiro TAGISHI
Hideyuki SAKAI (Tokyo Univ.)
Yoshitaka FUJITA (Osaka Univ.)
Hiroari MIYATAKE (KEK)
Zsolt FULOP (Hangarian Academy of Science)- 352 -

Sadao MOMOTA (Kouchi Univ. of Technology)
Takeshi SUZUKI (Saitama Univ.)
Jun HASEGAWA (Tokyo Institute of Technology)
Tadayuki TAKAHASHI
Yoshihide FUCHI (KEK)
Kazuo IEKI (Rikkyo Univ.)
Shintaro NAKAYAMA (Tokushima Univ.)
Tsuneyasu MORIKAWA (Kyusyu Univ.)
Harutaka SAKAGUCHI (Miyazaki Univ.)
Seigo KATO (Yamagata Univ.)
Mitsunori FUKUDA (Osaka Univ.)
Masahiko TANAKA (KEK)
Takashi NAKAMURA (Tokyo Institute of Techology)
Atsuko ODAHARA (Osaka Univ.)
Alberto MENGONI (JAXA)
Atsushi TAMII (Osaka Univ.)
Takashi TERANISHI (Kyusyu Univ.)
Tetsuro ISHII (JAEA)
Dombradi DOMBRADI (ATOMKI)
Takashi MIYASHI
Takao SAKAGUCHI (Brookhaven National Laboratory)
HongKhiem HONG (VAST)
Evgueni KUZMIN (Kurchatov Instutute)
Evgueni NIKOLSKI (Kurchatov Instutute)Alexey OGLOBLIN (Kurchatov Instutute)
GurgenTer AKOPYAN (Joint Institute for Nuclear Research)
Shigeru ISHIMOTO (KEK)
Dimitra PIERROUTSAKOU (INFN)
Shuwei XU
Cosimo SIGNORINI (Padova Univ.)
Takashi WAKUI (Tohoku Univ.)
Tomoko MIYAGISHI (National Cencer Center)
Nobuaki IMAI (KEK)
Yukie MAEDA (Miyazaki Univ.)
Kentaro YAKO (Tokyo Univ.)
Tao ZHENG (Peking Univ.)

Student Trainees
Keisuke ITOH (Saitama Univ.)
Ryohei MATSUMIYA (Osaka Univ.)
Kim ARAM (Ewaha Woman's Univ.)
Syumpei NOJI (Tokyo Univ.)
Tomomi KAWAHARA (Toho Univ.)- 353 -

Livio LAMIA (Univ. of Catania)
Maria SERGI (Univ. of Catania)
Vincenzo CRUCILLA (Univ. of Catania)
Chen JUN (Mc Master Univ.)
Kunihiko TAJIRI (Osaka Univ.)
Hyo-Soon JUNG (Chung-Ang Univ.)
Kiana SETOODEHN (Mc Master Univ.)
Yoshiaki NAKAYAMA (Tokyo Institute of Technology)
Daiki NISHIMURA (Osaka Univ.)
Ayako SASAKI (Tohoku Univ.)
Kana TANAKA (Tokyo Institute of Technology)
Nobuyuki KOBAYASHI (Tokyo Institute of Technology)
Kousuki NAMIHIRA (Saitama Univ.)
Isao HACHIUMA (Saitama Univ.)
Sebastiana PUGLIA (Univ. of Catania)
Gabor KISS (University of Debrecen & ATOMIKI)
Takashige HONDA (Rikkyo Univ.)
Masayuki KAZATO (Osaka Univ.)
Mi-Hee NAN (Ewaha Woman's Univ.)
Nam-Hee LEE (Ewaha Woman's Univ.)
Anna TAKASHIMA (Osaka Univ.)
Masaki SUGA (Osaka Univ.)
Yosuke KAWADA (Tokyo Institute of Technology)
Naoki TANAKA (Tokyo Institute of Technology)
Shigeki DEGUCHI (Tokyo Institute of Technology)
Naoto KUME (Tohoku Univ.)
Yuta HARA (Rikkyo Univ.)
Yuichi MATSUURA (Meiji Univ.)
Sayaka IZUMI (Tohoku Univ.)
Hiroyuki OUCHI (Tohoku Univ.)
Tomonori SUZUKI (Tohoku Univ.)
Kensuke UCHIDA (Tohoku Univ.)
Yuichi NAMIKI (Niigata Univ.)
Yuki OHKUMA (Niigata Univ.)
Shinji SUZUKI (Niigata Univ.)
Ngyuen THO (Graduate School, OP, VAST)
Kyoko YAMAGUCHI (Osaka Univ.)
Kanako YAMAGUCHI (Tsukuba Univ.)
Toru SAITO (Miyazaki Univ.)
Yosuki ITO (Osaka Univ.)
Yo KENMOKU (Osaka Univ.)
Masaaki TACHI (Rikkyo Univ.)
Kensuki TANAKA (Rikkyo Univ.)- 354 -

Anna SHIBUYA (Toho Univ.)
Sotaro OSHIMA
Yunju LI (Institute of Modern Pysics)
Jun SU (Institute of Modern Pysics)
Shiwei XU (Institute of Modern Pysics)
Jun HU (Institute of Modern Pysics)
Masayuki NAGASHIMA (Niigata Univ.)
Yuta MIURA (Tohoku Univ.)
Yuki KATO (Meiji Univ.)
Koutaro TAKAHASHI (Tokyo Institute of Technology)
Takayuki SAKO (Tokyo Institute of Technology)
Riyato KAMBAYASHI (Rikkyo Univ.)
Takahiro NISHIGUTI (Aoyama Gakuin Univ.)
Yudai ICHIKAWA (Kyoto Univ.)John CAPPINO (Mc Master Univ.)
Duy NGUYEN (Vietnamese Academy of Science and Technology)
Keishun YAMAMURA (Fukui Univ. of Technology)

Visiting Technician
HenriPatrice GANGNANT
PatriceJean-Francois LIBIN
VincentCharles SPITAELS

Secretary
Emiko ISOGAI- 355 -

㪩㪠㪙㪝㩷㪩㪼㫊㪼㪸㫉㪺㪿㩷㪛㫀㫍㫀㫊㫀㫆㫅㩷㪩㪸㪻㫀㫆㪸㪺㫋㫀㫍㪼㩷㪠㫊㫆㫋㫆㫇㪼㩷㪧㪿㫐㫊㫀㪺㫊㩷㪣㪸㪹㫆㫉㪸㫋㫆㫉㫐㩷
1. Abstract
This laboratory explores exotic nuclear structures and dynamics in exotic nuclei that havenever been investigated before, such as those with largely imbalanced proton and neutron
numbers. Our aim is to develop new experimental techniques utilizing fast RI beams todiscover new phenomena and properties in exotic nuclei. Another important subject is theequation-of-state in asymmetric nuclear matter, and its association with the origin of elements
and with neutron stars. For instance, we are making attempts to the better understandunderlyning mechanism for exotic stability-enhancements of very neutron-rich fluorine
isotopes, the large deformation of the nucleus 34Mg with N=22 in spite of its vicinity to the
N=20 magic neutron number and anomalous collectivity in 16C. We are further extending thesestudies to medium- and heavy-mass regions by developing facilities, detectors and uniquemethods at RIBF, thereby leading on the challenging task to find new exotic phenomena. We
also perform numerical simulations of nucleosynthesis under the environment of core-collapse
supernovae, and moreover quest for footprints of supernovae and solar activities in the past,embedded in Antarctic ice core.
2. Major Research Subjects(1) Study of structure and dynamics of exotic nuclei through developments of new tools interms of reaction- and technique-based methodology(2) Research on EOS in asymmetric nuclear matter via heavy-ion induced reactions(3) Promotion of nuclear astrophysics in an interdisciplinary organization(4) Detector developments for spectroscopy and reaction studies
3. Summary of Research Activity(1) Missing mass method
Missing mass technique is promising for future radioactive isotope programs at RIBF.
Detection of recoil particles from target is essential in excitation energy determination ofparticle unbound states without any assumption of particle- and gamma-decay processes, andalso giving us transfer angular momentum from the angular distribution measurement. We
have developed a solid hydrogen target as well as a detector system called ESPRI for
proton-(in)elastic scattering. In 2009, the ESPRI system was exported to GSI to perform anexperiment. In addition, we prepared a first missing mass experiment at RIBF, where thestart-of-art detector MUST2 will be invited from France. A result obtained from spectroscopyon 12O with MUST2 at GANIL was published in PRL.
(2) In-beam gamma spectroscopy
In the medium and heavy mass region explored at RIBF, collective natures of nuclei are one ofimportant subjects, which are obtained through production and observation of high excited andhigh spin states. To populate such states, heavy-ion induced reactions such as fragmentation,
fission are useful. So far, we have developed two-step fragmentation method as an efficientmethod to identify and populate excited states, and lifetime measurements to deduce transition
strength. At the end of 2008, the first spectroscopy on nuclei island-of-inversion region was
performed and the result on the first excited state in 32Ne was published in PRL in 2009. At theend of 2009, the second campaign of in-beam gamma spectroscopy was organized and- 356 -

backgrounds originating from atomic processes in heavy target were investigated.
(3) Decay spectroscopy
Beta- and isomer-spectroscopy is an efficient method for studying nuclear structure, especiallyfor non-yrast levels. We had accumulated experimental techniques at the RIPS facility toinvestigate nuclear structure in light mass region via beta-gamma and beta-p coincidence.
Concerning the medium and heavy mass region available at RIBF, we have developed two
position-sensitive active-stoppers to achieve low-background via position correlation;
strip-silicon detectors and a cylindrical active stopper called CAITEN. At the end of 2009, thefirst decay spectroscopy on neutron-rich nuclei with A~100 was performed at the new facilityof RIBF. At the same time, the CAITEN detector was successfully tested with fragments
produced with a 48Ca beam.
(4) Equation-of-state via heavy-ion central collisions
Equation-of-state in asymmetric nuclear matter is one of major subjects in physics of exotic
nuclei. Concerning RIBF programs, a detector for pions produced in heavy-ion collisions isbeing tested at the HIMAC. In addition, a TPC for the SAMURAI spectrometer is being
designed.
(5) Interdisciplinary study for nuclear astrophysics
To understand the origin of elements beyond ion, interdisciplinary works are important inlinking data from nuclear physics program. We are promoting simulation of nucleosynthesis in
the r-process path, and investigation of Antarctic ice core to search for footprints of supernovae
as well as solar activity in the past via mass spectrometer, to link data obtained from nuclear
physics program.

Head
Hiroyoshi SAKURAI
Members
Takashi ICHIHARA
Takashi KISHIDA
Yoichi NAKAI
Shunji NISHIMURA
Hideaki OTSUHeiko SCHEIT
Nishina Center Researcher
Yuko MOTIZUKI
Research Associate
Hiroshi WATANABE
Satoshi TAKEUCHI
Mizuki NISHIMURA- 357 -

Special Postdoctoral Researcher
Maya TAKECHI
Satoshi SAKAGUCHI
Foreign Postdoctoral Researcher
David STEPPENBECK
Zhihuan LI
Senior Visiting Scientist
Wolfgang MITTIG (Michigan State University, USA)
Visiting Scientists
Sachiko AMARI (Washington Univ.,USA)
Koichiro ASAHI (Tokyo Institute of Technology)
Sudhee BANERJEE (Variable Energy Cyclotron Center, India)
Xiangzhou CAI (Shanghai Inst. Applied Physics, China)
Junsei CHIBA (Tokyo University of Science)
Alfred DEWALD (Univ. Cologna Insti. Nucl. Phys.)
Deqing FANG (Shanghai Inst. Applied Physics, China)
Adrian GELBERG (Univ. zu KoelnInst. Fur Kern Physik, Germany)
Wei GUO (Shanghai Inst. Applied Physics, China)
Kaoru HARA (University of Tsukuba)
Steven KARATAGLIDIS (Rhodes Univ.,South Africa)
Hiroyuki KOURA (JAEA)
Yugang MA (Shanghai Inst. Applied Physics, China)
Hideki MADOKORO (Mitsubishi Heavy Industries, Ltd)
Masayuki MATSUO (Grad. Sch. of Sci. and Tech., Niigata Univ, )Tetsuya MURAKAMI (Kyoto Univ.)
Jiro MURATA (Rikkyo Univ.)
Tetsuo NORO (Kyusyu Univ. Fac. of Sci.)
Akira ONO (Tohoku Univ.)
Naohiko OTSUKA (International Atomic Energy Agency, Austria)
YURI PENIONZHKEVICH (Flerov Lab. Nucl. Reactions, JINR, Russia)
Simona SCHEIT (Univ. of Tokyo)
Toshiyuki SUMIKAMA (Tokyo University of Science)
Takahiro TACHIBANA (Waseda High Sch., Waseda Univ.)
Kohji TAKAHASHI (Universite Libre de Bruxelles, Belgium)
Noboru TAKIGAWA (Fac. of Sci., Tohoku Univ.)
Oleg TARASOV (MSU, NSCL, USA)
Ryouichi WADA (Texas A&M Univ., USA)
Juzo ZENIHIRO (Grad. Sch. of Sci., Kyoto Univ.)
Shuangquan ZHANG (Peking Univ., China)
Yumin ZHAO (Shanghai Jiao Tong Univ.)- 358 -

Contract Researcher
Yasuyuki GONO
Students
Junior Research Associate
Takamasa KUBOKI
Student Trainees
Shoichiro EBESU (Kyoto Univ.)
Yuhei HASHIZUME (Tsukuba Univ.)
Maki HATA (Rikkyo Univ.)
Chihiro ISHII (Tokyo University of Science)
Yoshihiko IWAO (Kyoto Univ.)
Hiroaki MATSUMOTO (Kyoto Univ.)
Minori NIITA (Rikkyo Univ.)
Ken-ichiro OGAWA (Tsukuba Univ.)
Kensuke OKADA (Rikkyo Univ.)
Akio SHIRAKI (Tokyo Univ.)
Daisuke SUZUKI (Tokyo Univ.)
Hirotake TAKAHASHI (Shinsyu Univ.)
Nobuya UEMATSU (Tokyo University of Science)
Hideakira YOSHII (Tokyo University of Science)
Kenta YOSHINAGA (Tokyo University of Science)
IPA
Kuoang LI (Peking Univ., China)
Visiting Rsearcher
Pieter DOORNENBAL (JSPS Fellow)
Mattias LANTZ (JSPS Fellow)
Secretary
Tomoko FUJII (Temporary staff)- 359 -

���� �������� ��������
���������� ������� ����������
1 Abstract
The elements with their atomic number Z>103 are called as trans-actinide or superheavy
elements. The chemical properties of those elements have not yet been studied in detail.
Those elements does not exist in nature therefore, they must be produced artificially for
scientific studies. In our laboratory, we have been studying the physical and chemical
properties of the superheavy elements utilizing the accelerators in RIKEN and various
methods of efficient production for the superheavy elements.
2 Major Research Subjects(1) Search for new superheavy elements(2) Decay spectroscopy of the heaviest nuclei(3) Study of the chemical properties of the heaviest elements(4) Study of the reaction mechanism of the fusion process (theory)
3 Summary of Research Activity(1) Searching for new elements
To expand the periodic table of elements and the nuclear chart, we will search for new
elements.
(2)Spectroscopic study of the nucleus of heavy elements
Using the high sensitivity system for detecting the heaviest element, we plan toperform a spectroscopic study of nuclei of the heavy elements.
(3) Chemistry of superheavy elements
Study of chemistry of the trans-actinide (superheavy element) has just started
world-wide, making it a new frontier in the field of chemistry. Relativistic effects inchemical property are predicted by many theoretical studies. We will try to develop
this new field.
(4) Study of a reaction mechanism for fusion process
Superheavy elements have been produced by complete fusion reaction of two heavy
nuclei. However, the reaction mechanism of the fusion process is still not wellunderstood theoretically. When we design an experiment to synthesize nuclei of thesuperheavy elements, we need to determine a beam-target combination and the mostappropriate reaction energy. This is when the theory becomes important. We will try
to develop a reaction theory useful in designing an experiment by collaborating with thetheorists.

Head
Kosuke MORITA

Members
Hiromitsu HABA
Kouji MORIMOTO- 360 -

Nishina Center Researcher
Daiya KAJI

Research Associate
Yoshitaka KASAMATU

Special Postdoctoral Researcher
Kazutaka OZEKI
Yuki KUDOU

Contract Technical Scientist
Akira YONEDA

Visiting Scientists
Kazuhiko AKIYAMA (Tokyo Metropolitan Univ.)
Masato ASAI (Japan Atomic Energy Agency)
Shin-ichi GOTO (Niigata Univ.)
Kouichi HAGINO (Tohoku Univ.)
Kentaro HIROSE (Tohoku Univ.)
Hidetoshi KIKUNAGA (Osaka Univ.)
Hisaaki KUDO (Fac. Sci., Niigata Univ.)
Yuichiro NAGAME (Japan Atomic Energy Agency)
Tetsuya MURAKAMI (Grad. Sch. Sci., Kyoto Univ.)
Minoru SAKAMA (Tokushima Univ.)
Tsutomu Ohtsuki (Tohoku Univ.)
Atsushi SHINOHARA (Osaka Univ.)
Nozomi SATO (Japan Atomic Energy Agency)
Tetsuya SATO (Japan Atomic Energy Agency)
Keisuke SUEKI (Grad. Sch. Pure Appl. Sci., Univ. Tsukuba)
Fuyuki TOKANAI (Dept. Phys., Yamagata Univ.)
Atsushi TOYOSHIMA (Japan Atomic Energy Agency)
Kazuaki TSUKADA (Japan Atomic Energy Agency)
Akihiko YOKOYAMA (Dept. Chemi., Kanazawa Univ.)
Takashi YOSHIMURA (Osaka Univ.)

Research Consultants
Takashi INAMURA
Kenji KATORI
Toru NOMURA

Students
Junior Research Associate- 361 -

Student Trainees
Takayuki SUMITA (Tokyo Univ. of Science)
Mikio ARAKI (Dept. Chem., Kanazawa Univ.)
Kazuhiro OOE (Osaka Univ.)
Yukiko KOMORI (Osaka Univ.)
Ai KURIYAMA (Osaka Univ.)
Yuki KIKUTANI (Osaka Univ.)
Hideki KAIYA (Kanazawa Univ.)
Yuki TAKEDA (Kanazawa Univ.)
Reona TAKAYAMA (Osaka Univ.)
Hiroyuki FUJISAWA (Osaka Univ.)
Ryutaro SAKAI (Saitama Univ.)
Keita MAYAMA (Yamagata Univ.)
Mirei TAKEYAMA (Yamagata Univ.)
Saori NAMAI (Yamagata Univ.)- 362 -

�I�� �esearc� Di�isio�Acce�erator Group （Group Director ： Osamu KAMIGAITO）
Acce�erator ��D Team
1. Abstract
We are developing the key hardware in upgrading the RIBF accelerator complex. Firstly we aredeveloping the challenging superconducting coils for the new 28 GHz ECR ion source which is
being developed in order to increase the intensity of uranium beam. We are designing LEBT
(Low Energy Beam Transport) which transport the high power beam from the ion source to thenext injector linac. Correct estimations of neutralization of space charge forces are hard task.
Finally we are developling long-lived charge stripper foils which are installed to breed the ion
charges for reduction of their magnetic rigidities. We are also developing gas or windlow-lessliquid lithium strippers.
2. Major Research Subjects(1) Development of superconducting technology in acceleration system.
(2) Development of the LEBT(Low Energy Beam Transport) and the new injector for the highpower beams.
(3) Development of charge strippers for high power beams (foil, gas, liquid)
3. Summary of Research Activity(1) Development of superconducting technology in acceleration system.
Ohnishi, J.
We are developing the challenging superconducting magnets for the 28GHz ECR ion source.
We just started to study the possibility of the superconducting cavity in the RIBF accelerator
complex.
(2) Development of the LEBT (Low Energy Beam Transport) and the new injector for the highpower beams.
Sato, Y., Okuno, H.,
We are developing the LEBT for the ion beams from the new 28GHz ion source. We are also
studying space charge effects in the new injector for the RIBF accelerator complex.
(3)Development of charge strippers for high power beams (foil, gas, liquid)
Hasebe, H., Kuboki, H., Yokouchi, S., Okuno, H.,
We are developing the long lived charge stripper for high power ion beams. Foils, gas and liquid
for the strippers are being studied in parallel.

Team Leader
Hiroki OKUNO
Members
Jun-ichi OHNISHI- 363 -

Nishina center engineer
Hiroo HASEBE
Contract Researcher
Hironori KUBOKI
Yoichi SATO
Visiting Scientists
Noriyosu HAYASHIZAKI (Tokyo Institute of Technology)
Mitsuhiro FUKUDA (RCNP, Osaka Univ.)
Andreas ADELMANN (PSI, Switzerland)
Research Consultants
Yoshiaki CHIBA
Hiroshi FUJISAWA
Shigeru YOKOUCHI
Students
Student trainees
Hiroaki MATSUBARA (Grad Sch. Sci., Osaka Univ.)- 364 -

�I�� �esearc� Di�isio�Acce�erator Group （Group Director ： Osamu KAMIGAITO）
Io� �ource Team
1. Abstract
Our aim is to operate and develop the ECR ion sources for the accelerator-complex system of
the RI Beam Factory. We focus on further upgrading the performance of the RI Beam Factorythrough the design and fabrication of a superconducting ECR heavy-ion source for productionof high-intensity uranium ions.
2. Major Research Subjects(1) Operation and development of the ECR ion sources(2) Development of a superconducting ECR heavy-ion source for production of high-intensity
uranium ions
3. Summary of Research Activity(1) Operation and development of ECR ion sources
T. Nakagawa, M. Kidera, Y. Higurashi, H. Haba, T. Kageyama and A. Goto
We routinely produce and supply various kinds of heavy ions such as zinc and neon ions forthe super-heavy element serach experiment as well as uranium ions for RIBF experiments. We
also perform R&D’s to meet the requirements for stable supply of high-intensity heavy ion
beams.
(2) Development of a superconducting ECR ion source for use in production of a high-intensity
uranium beam
T. Nakagawa, J. Ohnishi, M. Kidera, Y. Higurashi, H. Haba and A. Goto
The RIBF is required to supply uranium beams with very high intensity so as to produce RI’s.
We have designed and are fabricating an ECR ion source with high magnetic field and highmicrowave-frequency, since the existing ECR ion sources have their limits in beam intensity.
The coils of this ion source are designed to be superconducting for the production of highmagnetic field. We are also designing the low-energy beam transport line of thesuperconducting ECR ion source.

Team Leader
Takahide Nakagawa
Members
Hiromitsu HABA
Tadashi KAGEYAMA

Contract Researcher
Yoshihide HIGURASHI
Masanori KIDERA
Visiting Scientists
Takehiro MATSUSE (Fac. Text. Sci. Technol., Shinshu Univ.）- 365 -

�I�� �esearc� Di�isio�Acce�erator Group （Group Director ： Osamu KAMIGAITO）
�I�A� Team
1. Abstract
The operation and maintenance of the RIKEN Heavy-ion Linac (RILAC) have been carried out.
There are the two modes, the standalone mode, in which the beam is delivered directly to thelow-energy beam user in the RILAC, and the injection mode, in which the RILAC beam is
injected to the RIKEN Ring Cyclotron (RRC). The RILAC is composed of two ion sources,
the frequency-variable RFQ linac, six frequency-variable cavities, and six energy booster
cavities (CSM). The maintenance of these devices is important to keep the log-term stabilityof RILAC beams.
2. Major Research Subjects(1) The long term stability of the RILAC operation.
(2) Improvement of efficiency of the RILAC operation.
3. Summary of Research Activity
The RIKEN Heavy-ion Linac (RILAC) is a frequency-tunable linac. The RILAC is
composed of two Heavy-ion ECR ion sources, RFQ linac, six main cavities, and six energy
booster cavities. Thousands hours are spent in a year for delivering many kinds of heavy-ion
beams to various experiments.
The RILAC has two operation modes: the stand-alone operation delivering low-energy beams
directly to experiments and the injection mode operation supplying beams into the RIKEN
Ring Cyclotron (RRC). In the first mode, the RILAC supplies very important beam to the
nuclear physics experiment of “the research of super heavy elements”. In the second mode,
the RILAC plays very important role as upstream end of the RIBF accelerators.
The maintenance is very important in order to keep the high quality performance of the RILAC.
Improvements are always carried out for the purpose of more efficient operation.

Team Leader
Eiji IKEZAWA
MemberYutaka WATANABE
Shigeaki ARAI
Research Consultants
Toshiya CHIBA
Masatake HEMMI
Yoshitoshi MIYAZAWA- 366 -

�I�� �esearc� Di�isio�Acce�erator Group （Group Director ： Osamu KAMIGAITO）
��c�otro� Team
1. Abstract
Together with other teams of Nishina Center accelerator division, maintaining and improving
the RIBF cyclotron complex. The accelerator provides high intensity heavy ions. Our mission
is to have stable operation of cyclotrons for high power beam operation. Recently stabilizationof the rf system is a key issue to provide 10 kW heavy ion beam.
2. Major Research Subjects(1) RF technology for Cyclotrons(2) Beam-RF correlation analysis(4) Maintenance and improvement of RIBF cyclotrons and linacs.
(5) Design and construction of new injector linac.
(6) Single turn operation for polarized deuteron beams.
3. Summary of Research Activity
Development of the rf system for a stable operation.
Improvement and maitainance of rf devices.
Correlation analysis between rf and beam.

Team Leader
Naruhiko SAKAMOTO
Members

Research Associate
Kenji SUDA

- 367 -

�I�� �esearc� Di�isio�Acce�erator Group （Group Director ： Osamu KAMIGAITO）
�eam D��amics a�� Dia��ostics Team
1. Abstract
In order to realize stable and efficient operations of RIBF accelerator complex, various
improvements including beam diagnosis, computer control, power supplies have been
performed. Our final goal is to establish simulation-based operation of RIBF accelerator
complex.
2. Major Research Subjects(1) Improvement on the beam transmission along the multi-stage accelerator system.
(2) Development of beam diagnosis.
(3) Development of computer control.
(4) Establishment of long-term stabilities of magnet and magnet power supplies.
3. Summary of Research Activity(1) Development of the beam diagnostic technology
We have improved existing beam intensity monitors (Faraday cup) for precise measurementsof heavy ions like uranium. In addition, non-destructive beam intensity monitor using SQUID
have been developed. These modifications resulted in a great improvement of beamtransmission efficiency.
(2) Development of the computer control system of accelerator
EPICS-based control system and a home-made beam interlock system have been stably
operated. We also applied embedded EPICS system on F3RP61-2L to our new injector system
RILAC2.
(3) Stability tests of old power supplies
We tested long-term stabilities of old power supplies used for more than twenty years torealize stable operation of accelerator complex.
(4) New injector system RILAC2Team Leader
Nobuhisa FUKUNISHI
Members
Masaki FUJIMAKI
Sachiko ITO
Keiko KUMAGAI
Tamaki WATANABE
Contract Technical Scientist
Misaki KOBAYASHI-KOMIYAMA
Kazunari YAMADA
Hiroshi WATANABE
Makoto NAGASE- 368 -

Visiting Scientists
Hiromichi RYUTO (Photonics and Electronics Science and Engineering Center,
Kyoto Univ.)
Jun-ichi ODAGIRIYuichiro SASAKI
Research Consultants
Jiro FUJITA- 369 -

�I�� �esearc� Di�isio�Acce�erator Group （Group Director ： Osamu KAMIGAITO）
�r�o�e�ic Tec��o�o�� Team
1. Abstract
We are operating the cryogenic system for the superconducting ring cyclotron in RIBF. We areoperating the helium cryogenic system in the south area of RIKEN Wako campus anddelivering the liquid helium to users in RIKEN. We are trying to collect efficiently gas
helium after usage of liquid helium.
2. Major Research Subjects(1) Operation of the cryogenic system for the superconducting ring cyclotron in RIBF
(2) Operation of the helium cryogenic plant in the south area of Wako campus and delivering
the liquid helium to users in Wako campus.
3. Summary of Research Activity(1) Operation of the cryogenic system for the superconducting ring cyclotron in RIBF
Okuno, H., Dantsuka, T., Maie, T.
(2) Operation of the helium cryogenic plant in the south area of Wako campus and delivering
the liquid helium to users in Wako campus.
Dantsuka, T., Odashima, Y., Nakamura, M., Maie, T., Ikegami, K., Okuno., H.

Team Leader
Hiroki OKUNO
Members
Masato NAKAMURA
Nishina Center Engineer
Takeshi MAIE
Technical Staff-I
Tomoyuki DANTSUKA
Research Consultant
Kumio IKEGAMI
Yutaka ODAJIMA
Ken-ici KATO

- 370 -

�I�� �esearc� Di�ision
Instru�entation De�e�op�ent Group （Group Director ： Ｍasanori WAKASUGI）
S��W�I �ea�
1. Abstract
A next-generation slow radioactive nuclear ion beam facility (SLOWRI) which provides slow,
high-purity and small emittance ion beams of all elements is being build as one of the principal
facilities at the RIKEN RI-beam factory (RIBF). High energy radioactive ion beams from the
projectile fragment separator BigRIPS are thermalized in a large gas catcher cell. The
thermalized ions in the gas cell are guided and extracted to a vacuum environment by a
combination of dc electric fields and inhomogeneous rf fields (rf carpet ion guide). From there
the slow ion beam is delivered via a mass separator and a switchyard to various devices: such as
an ion trap, a collinear fast beam apparatus, and a multi-reflection time of flight mass
spectrometer. In the R&D works at the present RIKEN facility, an overall efficiency of 5% for a
100A MeV 8Li ion beam from the present projectile fragment separator RIPS was achieved andthe dependence of the efficiency on the ion beam intensity was investigated.
First spectroscopy experiment at the prototype SLOWI was performed on Be isotopes.
Energetic ions of 7,10,11Be from the RIPS were trapped and laser cooled in a linear rf trap andprecision spectroscopy was performed. The evaluated ion temperature of <10 mK demonstrates
that a reduction of more than 15 orders of magnitude for the kinetic energy of radioactive Be
was achieved online. Precise investigation of the hyperfine structure will confirm the anomalous
mean radius of the valence neutron of the so called neutron halo nucleus.
Other spectroscopy experiments using the slow RI-beams are also under progress in off-line
setups. A collinear fast beam apparatus for nuclear charge radii measurements was build andtested with stable Ar+ ion beams. A multi-reflection time-of-flight mass spectrograph was buildfor precise and fast measurements of short-lived radioactive nuclei. A high mass resolving
power of 200,000 has been achieved with a 5 ms measurement period.
An advanced SLOWRI facility is also proposed. The expected number of nuclides which canbe investigated at SLOWRI is more than 3000, however, the realistic beam time for eachexperiment would be very limited. The advanced facility will parasitically provide slow
RI-beams everyday as long as the fragment separator BigRIPS is operated. The parasitic beam
can be produced from those nuclei dumped at the first focal plane slits of BigRIPS by placing acompact gas catcher cell. The thermalized and neutralized RI in the cell can be re-ionized at theexit of the cell by resonance laser ionization. Development the new scheme, named PALIS, isunderway.
2. Major Research Subjects(1) Development and construction of the next-generation slow RI-beam facility(2) Precision hyperfine spectroscopy of trapped ions for magnetization distribution in a halo
nucleus(3) Nuclear charge radii measurements using ion trap and collinear fast beam apparatus(4) Precision mass measurements of short-lived nuclei using a multi-reflection TOF mass
spectrograph(5) Development of deceleration and cooling devices for energetic beams using gas cell and rf
fields.

- 371 -

(6)Atomic physics and fundamental symmetry research investigating nuclear decay of an
isolated atom
(7) Development of parasitic slow RI-beam production method using resonance laser
ionization.

3. Summary of Research Activity(1) Development of universal slow RI-beam facility
WADA, Michiharu, TAKAMINE, Aiko, SCHURY Peter, SONODA, Tetsu, OKADA,
Kunihiro, KANAI, Yasuyuki, YOSHIDA, Atsushi, KUBO, Toshiyuki, YAMAZAKI,
Yasunori, WOLLNIK, Hermann, SCHUESSLER, Hans, NODA, Koji, OHTANI, Shunsuke,
KATAYAMA Ichiro
A next-generation slow radioactive nuclear ion beam facility (SLOWRI) which provides slow,
high-purity and small emittance ion beams of all elements is being build as one of the principal
facilities at the RIKEN RI-beam factory (RIBF). High energy radioactive ion beams from the
projectile fragment separator BigRIPS are thermalized in a large gas catcher cell. The
thermalized ions in the gas cell are guided and extracted to a vacuum environment by a
combination of dc electric fields and inhomogeneous rf fields (rf carpet ion guide). From there
the slow ion beam is delivered via a mass separator and a switchyard to various devices: such as
an ion trap, a collinear fast beam apparatus, and a multi-reflection time of flight mass
spectrometer. In the R&D works at the present RIKEN facility, an overall efficiency of 5% for a
100A MeV 8Li ion beam from the present projectile fragment separator RIPS was achieved andthe dependence of the efficiency on the ion beam intensity was investigated. An advanced gas
cell with cryogenic cooler and an additional rf carpet at the wall of the cell is underdevelopment.
(2) Laser spectroscopy of trapped radioactive beryllium isotope ions
WADA, Michiharu, TAKAMINE, Aiko, SCHURY Peter, SONODA Tetsu, OKADA,
Kunihiro, KANAI, Yasuyuki, YOSHIDA, Atsushi, KUBO, Toshiyuki, YAMAZAKI,
Yasunori, WOLLNIK, Hermann, SCHUESSLER, Hans, NODA, Koji, OHTANI, Shunsuke,
KATAYAMA Ichiro
As a first application of the prototype SLOWRI setup, we are applying hyperfine structure
spectroscopy to the beryllium isotopes to determine in particular the anomalous radius of thevalence neutron of the neutron halo nucleus 11Be, and to determine the charge radii of theseberyllium isotopes through laser-laser double resonance spectroscopy of laser-cooled ions. Lasercooling is an essential prerequisite for these planned experiments. However, the exact resonancefrequencies of the cooling transitions for radioactive beryllium isotopes are not known. In suchlight elements, the isotope shifts in the atomic transitions are larger than several 10 GHz andtheir dominant parts are due to complicated multi-electron correlations. Some theoretical works
on the isotope shifts of the beryllium ion exist, however the values contradict each other at thelevel of accuracy needed.
The first laser spectroscopy experiments for beryllium isotopes were performed to measure theresonance frequencies of 2s 2S1/2 - 2p 2P3/2 transition of 7Be+, 9Be+, 10Be+ and 10Be+ ions and thenuclear charge radii of these Be isotopes were determined. The hyperfine structure of 11Be+ and7
Be+ ions using the laser-microwave double resonance spectroscopy were also performed and- 372 -

A(7Be+) = -742.7723(4) MHz and A(11Be+) = -2677.308(2) MHz were determined for the firsttime. Precision measurements of the nuclear magnetic moments of these Be isotopes are underpreparation.
(3) Development of a multi-reflection TOF mass spectrograph
WADA, Michiharu, SCHURY Peter, TAKAMINE, Aiko, SONODA Tetsu, OKADA,
Kunihiro, WOLLNIK, Hermann,
The atomic mass is one of the most important quantity of a nucleus and has been studied invarious methods since the early days of physics. Among many methods we chose amulti-reflection time-of-flight (MR-TOF) mass spectrometer. Slow RI beams extracted from the
RF ion-guide are bunch injected into the spectrometer with a repetition rate of ~500 Hz. The
spectrometer consists of two electrostatic mirrors between which the ions travel back and forth
repeatedly. These mirrors are designed such that energy-isochrononicity in the flight time isguaranteed during the multiple reflections while the flight time varies with the masses of ions.
A mass-resolving power of >200,000 has been obtained with about 500 reflections in a 30 cm
length spectrometer. This mass-resolving power should allow us to determine ion masses withan accuracy of 10-7. The advantages of the MR-TOF spectrometer are: 1) short measurement
periods, typically 2 ms, which allows all neutron rich nuclei to be investigated, 2) the device iscompact and its operation is simple, especially, it is independent from the all upstream devices,
accelerators and fragment separators, 3) ions of more than isobars can be measured
simultaneously, so that mass reference can easily be established in the mass spectra. In total,
the number of measurable nuclides within a limited beam time would be larger than that can beachieved by other methods. It should be noted here also that this method can be used evenduring a low-duty parasite beam time. An on-line MR-TOF mass spectrograph with 80 cm
length having an expected mass resolving power of 1,000,000 is under fabrication.
(4) Development of collinear fast beam apparatus for nuclear charge radii measurements
WADA, Michiharu, SCHUESSLER, Hans, IIMURA, Hideki, SONODA, Tetsu, SCHURY,Peter, TAKAMINE, Aiko, OKADA, Kunihiro, WOLLNIK, Hermann,
The root-mean-square charge radii of unstable nuclei have been determined exclusively by
isotope shift measurements of the optical transitions of singly-charged ions or neutral atoms bylaser spectroscopy. Many isotopes of alkaline, alkaline-earth, noble-gases and several otherelements have been measured by collinear laser spectroscopy since these ions have all good
optical transitions and are available at conventional ISOL facilities. However, isotopes of otherelements especially refractory and short-lived ones have not been investigated so far.
In SLOWRI, isotopes of all atomic elements will be provided as well collimated mono-energetic
beams. This should expand the range of applicable nuclides of laser spectroscopy. In the firstyears of the RIBF project, Ni and its vicinities, such as Ni, Co, Fe, Cr, Cu, Ga, Ge are planned
to be investigated. They all have possible optical transitions in the ground states of neutral
atoms with presently available laser systems. Some of them have so called recycle transitions
which enhance the detection probabilities noticeably. Also the multistep resonance ionization(RIS) method can be applied to the isotopes of Ni as well as those of some other elements. The
required minimum intensity for this method can be as low as 10 atoms per second.
We have built an off-line mass separator and a collinear fast beam apparatus with a large- 373 -

solid-angle fluorescence detector. A 617 nm transition of the metastable Ar+ ion at 20 keV
was measured with both collinear and anti-collinear geometry that allowed us to determine theabsolute resonant frequency of the transition at rest with more than 10 -8 accuracy. Such highaccuracy measurements for Ti and Ni isotopes are in progress.
(5) Development of parasitic slow RI-beam production scheme using resonance laser ionization
WADA, Michiharu, SONODA Tetsu, TAKAMINE, Aiko, OKADA, Kunihiro, MATSUO
Yukari, FURUKAWA, Takeshi, KOBAYASHI T., MIYATAKE Hiroari, JEONG Sun Chan,
ISHIYAMA, H., IMAI, N., HIRAYAMA Y., KATAYAMA I., TOMITA, H., IIMURA, H.,
SHINOZUKA T., WAKUI, T., HUYSE, M., VAN DUPPEN, P., KUDRYAVTSEV, Yu.,
SCHUESSLER, H., WOLLNIK, H.
More than 99.9% of RI ions produced in projectile fission or fragmentation are simply dumped
in the first dipole magnet and the slits. A new scheme, named PALIS, to rescue such dumped
precious RI using a compact gas catcher cell and resonance laser ionization was proposed. The
thermalized RI ions in a cell filled with Ar gas can be quickly neutralized and transported to theexit of the cell by gas flow. Irradiation of resonance lasers at the exit ionizes neutral RI atoms
efficiently and selectively. The ionized RI ions can be further selected by a magnetic mass
separator and transported to SLOWRI experimental area for spectroscopy experiment. The
resonance ionization scheme itself can also be a useful method to perform precision optical
spectroscopy of RI of many elements.
An off-line setup for resonance ionization in gas cell is under construction. Several pulsed dyelasers pumped by two excimer lasers are prepared. A gas cell test bench is also under design.

Head
Michiharu WADA

Members
Aiko TAKAMINE
Tetsu SONODA
Peter SCHURY
Kunihiro OKADA
Ichou KATAYAMA
Hideki IIMURA
Hans SCHUESSLER
Hermann WOLLNIK- 374 -

�I�� �esearc� Di�ision
Instru�entation De�e�op�ent Group （Group Director ： Ｍasanori WAKASUGI）
�o�ari�e� �I �ea� �ea�
1. Abstract
The team conducts the research and development on the production of spin-oriented
radioactive-isotope beams (RIBs), and applies it to the research on nuclear physics, fundamental
physics, and material science. The microscopic investigation of physical and chemical processes
is performed based on nuclear techniques which takes the advantage of intrinsic nuclear
properties and phenomena (spins, electromagnetic moments, decay modes etc.). In particular,
the precession/resonance of a polarized/aligned nuclear spin under an external field is observed
through a change in the angular distribution of radiation, for the study of nuclear structures via
nuclear moments. The experimental methods and devices for fundamental physics research withpolarized nuclei have been also developed. The same method, as well as the Möessbauer
technique, are used for the investigation of condensed matter such as semiconductor,
ferromagnets, fullerenes, systems with dilute magnetic impurities etc. by capitalizing
radioactive nuclei as microscopic probes into them. All these research activities are to beextended to wide variety of unstable nuclei which RI Beam Factory (RIBF) provides. A method
to produce beams of highly polarized radioactive nuclei, taking full advantage of RIBF, is being
developed.
2. Major Research Subjects(1) Nuclear-moment measurements of unstable nuclei(2) RIPS upgrade and the development of highly polarized slow RI beams(3) Fundamental physics: Study of symmetry(4) Condensed matter studies using radioactive nuclear probes
3. Summary of Research Activity(1) Nuclear-moment measurements of unstable nuclei
It has been revealed in our earlier work that spin-oriented RIBs can be obtained as a function of
their outgoing momentum in the projectile-fragmentation reaction. With the obtained
spin-polarized nuclei, ground- and excited-state nuclear moments can be determined by meansof the β-NMR and TDPAD methods, respectively. Based on these technique, we have recently
been conducted the nuclear-moments measurement of neutron-rich sd-shell around the neutron
magic number N=20. It has been proposed in this region that an inversion of amplitudes
between the sd normal and the pf intruder configurations would lead to deformation of theground states. Thus, the region of nuclei is called the island of inversion. The measured nuclear
moments are expected to provide microscopic properties for those nuclei of interest. The
sub-themes are the following:z Studies of shell evolution through nuclear-moment measurements of neutron-rich nuclei.
The targets are:
¾ the neutron-rich aluminum isotopes 30-34Al for the study of the island of inversion
phenomena around N=20,¾ neutron-rich S, P, and Si isotopes for the magicity of N=28, and¾ N∼40 nuclei 54mNi and 69mCu for the study of isospin symmetry and the magicity.
z Development of a new method to produce highly spin-aligned RIBs through the two-step- 375 -

fragmentation reaction and its application to the isomeric-state magnetic-momentmeasurements.
z The ground-state electric quadrupole moment measurement of 23Al for the study of the
T=3/2 mirror symmetry.
(2) RIPS upgrade and the development of highly polarized slow RI beams
The upgrade of RIPS has been proposed in the phase-II programs. In the cyclotron-cascade
acceleration scheme, beams are accelerated up to the energy of E = 115 A MeV with IRC. In
this upgrade, the former fragment separator RIPS is equipped with a new beam line that delivers
beams of 115 A MeV heavy ions from the IRC cyclotron. RI beams produced by the primarybeams at such an intermediate energy are high enough to produce RIBs via
projectile-fragmentation reactions and suitably low in energy to be stopped in a sample materialof limited thicknesses. Compared with the production yield of RIBs in the present AVF-RRC
acceleration scheme, they are drastically increased. The design study of the upgrade program isin progress in our team. We noted that RIBs produced at E = 115 A MeV can be spin-oriented
so that the nuclear-moment measurements will be further conducted. Also, combining a new
atomic-beam resonance method to combine with fragmentation-based RI beams, which is underdevelopment, to this program, highly spin-polarized RI beams will be produced in a low
beam-energy region. Then, they could be useful not only for nuclear-moment measurements but
also for spin-related subjects in nuclear physics, fundamental physics, and material sciences.
(3) Fundamental physics: Study of symmetry
Nuclear spins of stable and unstable isotopes sometimes play important roles in fundamental
physics research. New experimental methods and devices have been developed for studies on
the violation of time reversal symmetry (T-violation) using spin-polarized nuclei. Theseexperiments aim detection of small frequency shift of the spin precession or measurement of the
T-odd angular correlation in β-decay as T-violating signals arising from new mechanisms
beyond the “Standard Model”. Sub-themes are the following:z Precision measurement of spin-precession frequency with a new type of the nuclear spinmaser for atomic EDM (Electric Dipole Moment) search.
z Development of a new Mott polarimeter for T-violation experiment using β-decay ofpolarized unstable nuclei.
(4) Condensed matter studies using radioactive nuclear probes
Utilizing RI beams as a probe, online Mössbauer spectroscopy and online perturbed angularcorrelation experiments have been carried out through the γ-ray measurements. The microscopic
structures, dynamics in ferromagnets, and properties of semiconductors have been investigatedfrom the deduced internal local fields and the spin relaxation of the probe in materials. The
β-NMR/NQR method is also utilized for these condensed matter studies. The methods andapparatus have been developed. Also, basic studies on the probe nuclei have been carried out.
Sub-themes are the following:z Study of “exotic” chemical states and the fast atomic-jump processes in solid with theonline Mössbauer spectroscopy of implanted 57Fez Development of the on-line perturbed angular-correlation method with 19O beams as a
new probez Study of the diffusion and segregation of Fe impurity atoms in Si through in-beam- 376 -

Mössbauer experiment with a Coulomb excited, recoil implanted 57Fe nuclei.
z Study of the fast diffusion of Cu impurity atoms in Si through β-NMR/NQR withimplanted 58Cu.

Team Leader
Hideki UENO
Members
Akihiro YOSHIMI
Yuichi ICHIKAWA
Yoshio KOBAYASHI- 377 -

�I�� �esearc� Di�ision
Instru�entation De�e�op�ent Group （Group Director ： Ｍasanori WAKASUGI）
�are �I�rin� �ea�
1. Abstract
We are developing the isochronous storage ring to measure the mass for rare radioactive
isotopes (Rare RI ring). It is assumed that uranium is synthesized by neutron capture process
after the supernovae explosion (r-process). To prove r-process, mass measurements for the rare
RI are indispensable. To deduce the mass, we measure the circulation time (cyclotron
frequency) for the rare RI inside the ring. RI beams produce in RIBF have some energy spread.
To compensate the spread, isochronicity inside the ring is indispensable (isochronous storagering). We will inject the rare RI one by one to the ring (individual injection) to identify the RI
event-by-event.
2. Major Research Subjects
Developments of isochronous storage ring to measure mass of rare RI.
3. Summary of Research Activity
Developments of isochronous storage ring to measure mass of rare RI.
The conceptual design for an isochronous storage ring has been finalized in this year. To
minimize construction cost, we plan to use the SHARAQ beam line as an injection beamtransport line for the isochronous ring and re-use TARN-II bending magnets, which have been
moved from KEK, as main components of the ring. R&D study of quick activated kicker
magnet system required for one by one injection has been started, and the feasibility will bedemonstrated in next year. Another important item in the ring is schottoki beam monitor, whichobserves single ion circulating the ring. It is now under designing, and it will be manufactured
in next year and installed in the HIMAC for test experiment.

Team Leader
Masanori WAKASUGI

Research Associate
Yoshitaka YAMAGUCHIJRA
Shinpei NAKAJIMA (Saitama University)
Tetsuaki MORIGUCHI (University of Tsukuba)

Visiting Scientists
Akira OZAWA (Inst. Phys., Univ. of Tsukuba)
Yusuke YASUDA (Inst. Phys., Univ. of Tsukuba)
Ichiro ARAI (Inst. Phys., Univ. of Tsukuba)
Takeshi SUZUKI (Saitama University)- 378 -

Takayuki YAMAGUCHI (Saitama University)
Takashi KIKUCHI (Nagaoka University of Technology)
Daisuke NAGAE (Inst. Phys., Univ. of Tsukuba)- 379 -

�I�� �esearc� Di�ision
Instru�entation De�e�op�ent Group （Group Director ： Ｍasanori WAKASUGI）
S��I� �ea�
1. Abstract
We aim at the investigation of internal nuclear structure of short-lived radioactive nuclei (RI) by
means of electron scattering. Electron scattering for RI's has never been performed duo toinability to make target of these nuclei. An electron-RI collider system, which requires a hugeaccelerator complex, has so far been unique solution to overcome the difficulty. We havedeveloped a novel internal target system named SCRIT (Self-Confining RI Ion Target) in anelectron storage ring to make the experiment easier with much compact experimental system.
An electron accelerator system required in this experiment has been constructed in this year, and
it is under commissioning. The SCRIT device, which will be installed in the accelerator, hasalso been manufactures.
2. Major Research Subjects
Development of the SCRIT technology and electron scattering for unstable nuclei.
3. Summary of Research Activity
Development of a novel internal target of unstable nuclei (SCRIT) in an electron storage ringfor electron scattering experiment.
(Wakasugi, Miyashita, Kurita, Suda, Tamae, Hori, Hara)
We have constructed an electron accelerator system, which consists of an injector microtron(RTM) and a storage ring (SR2). The commissioning and machine study is now in progress. The
SCRIT (Self-Confining Radioactive Ion Target) device was manufactured in this year and weare now making the preparation for installing to the SR2. In this electron scattering facility, we
will construct the U photo-fission ion source for RI production and an ISOL system for RI
injection into the SCRIT device. They are now under designing. Detector system for scatteredelectrons from the SCRIT is also under designing and it will be manufactured in next year. We
plan to start the electron scattering experiment for unstable nuclei from the beginning of 2012.

Team Leader
Masanori WAKASUGIMembers
Takashi EMOTO
Special Postdoctoral Researcher
Yuji MIYASHITA
Research Consultant
Shin-ichi ICHIKAWA
Masahiro HARA
Toshitada HORI

- 380 -

Visiting Scientists
Toshimi SUDA (Research Center of Electron Photon Science, Tohoku Univ.)
Tadaaki TAMAE (Research Center of Electron Photon Science, Tohoku Univ.)
Kazuyoshi KURITA (Inst. Phys., Rikkyo Univ.)- 381 -

��B� �ese�rch Di�isio��ese�rch ��stru�e�ts Group （Group Director ： Ｔoshiyuki KUBO）
G���� �e��
1 Abstract
Development and maintenance of devices related to study of the superheavy elements.
2 Major Research Subjects(1) Maintenance and development of recoil separators GARIS and GARIS-II.
(2) Maintenance and development of a focal-plane detector system and rapid chemistry devices.
3 Summary of Research Activity(1) Maintenance and development of recoil separator
A gas-filled recoil separator has been used as a main experimental device for the study ofsuperheavy elements. We will develop and maintain the related devices. We will also offeruser-support if a researcher wishes to use the devices for his/her own research program.
(3) Maintenance and development of focal-plane detectors and devices for fast chemistry
We will develop and maintain the focal-plane detector system for the study of the superheavy
elements. We do research and development of devices for fast chemistry of superheavy elements.
We also offer user‐support for potential users.

Team Leader
Kouji MORIMOTO
Special Postdoctoral Researcher
Daiya KAJI
Contract Technical Scientist
Akira YONEDA- 382 -

��B� �ese�rch Di�isio��ese�rch ��stru�e�ts Group （Group Director ： Ｔoshiyuki KUBO）
Bi����� �e��
1. Abstract
This team is in charge of design, construction, development and operation of BigRIPS in-flight
separator and its related research instruments at RI beam factory (RIBF). They are employed not
only for the production of RI beams but also the experimental studies using RI beams.
2. Major Research Subjects
Design, construction, development and operation of BigRIPS in-flight separator, RI-beamtransport lines, and their related research instruments
3. Summary of Research Activity
This team is in charge of design, construction, development and operation of BigRIPS in-flight
separator, RI-beam transport lines, and their related research instruments such as ZeroDegree
spectrometer at RI beam factory (RIBF). They are employed not only for the production of RI
beams but also various kinds of experimental studies using RI beams.
The research subjects may be summarized as follows:(1) General studies on RI-beam production using in-flight scheme.
(2) Studies on ion-optics of in-flight separators, including particle identification of RI beams(3) Simulation and optimization of RI-beam production.
(4) Development of beam-line detectors and their data acquisition system.
(5) Experimental studies on production reactions and unstable nuclei.
(6) Experimental studies of the limits of nuclear binding.
(7) Development of superconducting magnets and their helium cryogenic systems.
(8) Development of a high-power production target system.
(9) Development of a high-power beam dump system.
(10) Development of a remote maintenance and remote handling systems.
(11) Operation, maintenance and improvement of BigRIPS separator system, RI-beam transportlines, and their related research instruments such as Zero Degree spectrometer and so on.
(12) Experimental research using RI beams.

Team Leader
Toshiyuki KUBO
Members
Naohito INABE
Atsushi YOSHIDA
Koichi YOSHIDA
Masao OHTAKE
Yoshiyuki YANAGISAWA- 383 -

Contract Researchers
Kensuke KUSAKA
Tetsuya OHNISHI
Naoki FUKUDA
Hiroyuki TAKEDA
Research Associates
Daisuke KAMEDA
Kanenobu TANAKA
Part-time Staff
Hidekazu KUMAGAI
Visiting Scientist
Bradly SHERRILL (NSCL, Michigan State Univ., USA)
Daniel BAZIN (NSCL, Michigan State Univ., USA)
Anthony NETTLETON (NSCL, Michigan State Univ., USA)
Hans GEISSEL (GSI, Germany)
Martin WINKLER (GSI, Germany)
Michael FAMIANO (Western Michigan Univ., USA)
Shashikant MANIKONDA (Argonne National Lab., USA)
Yutaka MIZOI (Osaka Electro-Commnication Univ.)
Khiem LEHONG (IOP, Vietnamese Academy for Science and Technology)
Cuong PHANVIET (IOP, Vietnamese Academy for Science and Technology)- 384 -

��B� �ese�rch Di�isio��ese�rch ��stru�e�ts Group （Group Director ： Ｔoshiyuki KUBO）
���U��� �e��
1. Abstract
This team is in charge of design, development and construction of the SAMURAI spectrometerthat will be used for reaction experiments using RI beams at RI Beam Factory. SAMURAI
consists of a large superconducting dipole magnet and a variety of detectors to detect charged
particles and neutrons.
2. Major Research Subjects
Design, development and construction of the SAMURAI spectrometer at RI Beam Factory andits related research instruments.
3. Summary of Research Activity
This team is in charge of design, development and construction of the SAMURAI spectrometer
at RI Beam Factory. Consisting of a large superconducting dipole magnet and a variety ofdetectors to detect charged particles and neutrons, SAMURAI will be used for various reaction
studies with RI beams.
The research subjects may be summarized as follows:(1) Design, development and construction of a large superconducting dipole magnet that will be
the main component of the SAMURAI spectrometer.
(2) Design, development and construction of various detectors that are used for nuclear reaction
experiments using the SAMURAI spectrometer.

Team Leader
Toshiyuki KUBO

Members
Hiromi SATO
Ken-ichiro YONEDA
Yohei SIMIZU

Senior Visiting Scientist
Toshio KOBAYASHI (Tohoku University)- 385 -

��B� �ese�rch Di�isio��ese�rch ��stru�e�ts Group （Group Director ： Ｔoshiyuki KUBO）
�o�puti�� ��� �et�ork �e��
1. Abstract
The Computing and Network team is in charge of the development, management, and operationof the computing and networking environment, mail and information servers, and dataacquisition system; the team is also responsible for information security management at RIKEN
Nishina Center.
2. Major Research Subjects(1) Development, management, and operation of general computing servers(2) Development, management, and operation of mail and information servers(3) Development, management, and operation of the data acquisition system(4) Development, management, and operation of the network environment(5) Information security management
3. Summary of Research Activity
This team is in charge of the development, management, and operation of the computing andnetworking environment, mail and information servers, and data acquisition system; further, theteam is responsible for information security management. Details of the research activities will
be provided later in this progress report.
(1) Development, management, and operation of general computing servers
We are operating the Linux/Unix NIS/NFS cluster system for analysis of the experimental
data and general computing. This cluster system consists of eight computing servers with 28
CPU cores and a 20 TB RAID comprising highly reliable fiber channels (HDD). Approximately
500 user accounts are registered on this cluster system. We have adopted Scientific Linux,
which has been developed at Fermi National Laboratory, as the primary operating system.
Scientific Linux is widely used by the nuclear physics and high-energy physics communities, aswell as in accelerator research facilities worldwide.
The SSH login server is RIBF00.RIKEN.JP. Public-key authentication is used for SSH login to
improve information security.
(2) Development, management, and operation of mail and information servers
We are operating the RIBF.RIKEN.JP mail server. Postfix is used as the mail transport
software, and Dovecot is used for IMAP and POP services. These software packages enablesecure and reliable mail delivery. Front-end mail servers (RIBFSMTP1/RIBFSMTP2) are used
for tagging spam mails and isolating virus-infected mails. Sophos Email Security and Control(PMX) was installed on these servers in March 2008, and since then, it has been functioning
satisfactorily and serving the intended purposes. Almost 99% of the spam mails are identified
by PMX.
We are operating several information servers such as WWW servers, Wiki servers, indico
server, twitter server, Groupware servers, Windows Media streaming servers, and QuickTime
streaming servers.

- 386 -

An anonymous ftp server, FTP.RIKEN.JP, is managed and operated at RIKEN Nishina Center.
This server has a speed of 10 Gbps and is connected to the Local Area Network (LAN) via adual-port 10GbE NIC with a PCI Express interface. This server has an average network transfer
rate of approximately 50 MBps, and it is one of the most heavily loaded servers at RIKEN. A 26
TB SATA RAID system with a quad-port 8-Gbps fiber channel interface has been added to thisserver. Major Linux distributions, which include Scientific Linux, CentOS, Ubuntu, Fedora,
Debian, OpenSUSE, Mandrake, Slackware, and Vine, are mirrored daily at the ftp server for
facilitating high-speed access by the users. The archived data on the server can be accessed byusing anonymous ftp, http, and rsync protocols.
(3) Development, management, and operation of the data acquisition system
We are developing a data acquisition system for the RIBF. The functions of this system are
network-distributed data processing, hierarchical event building, and parallel readout, which areachieved using the newly developed software and commodity hardware. This system is bothversatile and scalable and hence meets the various requirements for RIBF experiments. The
system has a maximum data processing capability of around 40 MB/s. We are also developing atime-stamping system with a precision of 10 ns for the RIBF experiments.
(4) Development, management, and operation of the network environment
We have been managing the network environment in collaboration with Advanced Center for
Computing and Communications (ACCC). All the Ethernet ports of the information wall
sockets are capable achieving Gigabit Ethernet connection (10/100/1000BT). Many
(approximately 60) wireless LAN access points have been installed to cover almost the entire
area of Nishina Center.
(5) Information security management
It is essential to adopt proper information security measures for information assets. The mostimportant safety measures include (1) protection of information from virus attacks, (2) detectionof virus attacks, and (3) recovering information in the event of a virus attack. We are currently
involved in information security management at Nishina Center, in collaboration with ACCC.

Team Leader
Takashi ICHIHARA

MemberYasushi WATANABE
Hidetada BABA

- 387 -

��B� �ese�rch Di�isio��ese�rch ��stru�e�ts Group （Group Director ： Ｔoshiyuki KUBO）
Detector �e��
1. Abstract
This team is in charge of development, fabrication, and operation of various detector for
nuclear physics experiment in RIKEN Nishina center. Also the team organizes collaboration
work for detector technology among related research groups in order to improve mutual share ofknowledge and experience with both in the RIKEN and outside RIKEN.
2. Major Research Subjects(1) Development of silicon pixel detector.
(2). Development of high dynamic range preamplifier for silicon strip detector(3) Development of readout electronics for time projection chamber(4) Muon detector development for high energy hadron reaction experiment.
3. Summary of Research Activity
This team is presently focusing on developments of detectors for RHIC PHENIX experiments
and RIBF nuclear experiments.
(1) Development of silicon pixel detector.
RIKEN, Rikkyo, Kyoto, CNS and KEK group is responsible for the pixel ladder fabrications for
the RHIC PHENIX detector upgrade. The ladder is a module which is composed of pixel sensor
modules, support frame, and readout bus. These ladders will be installed in 2010 fall and will
generate physics data with 100 micron meter resolution for heavy flavor decay vertex
identification.
(2) Development of high dynamic range preamplifier
Coulomb break up experiment at RIBF needs high dynamic range silicon strip detector in order
to identify the charged particle from proton to Sn. We propose to use both high gain and low
gain preamplifiers. Dual hybrid preamplifiers with discrete devices were developed andproofed the principal. Then an application specific integrated circuit was designed andfabricated by collaboration with KEK and CNS. Also We collaborate Washington University forreadout.

(3) Development of readout electronics for time projection chamber
A time projection chamber will be used for SAMURAI spectrometer. RIKEN and Kyoto groupis in charge of the readout electronics. We started the conceptual design.
(4) Development of the detector with high position resolution and high counting rate
RIBF experiment must have high rate capability to explore low cross section events. We would
like to develop such detector by using MICROMEGAS or GEM technology.
(5) Muon detector development for high energy hadron reaction experiment- 388 -

Muon detector at the RHIC PHENIX experiments has been upgrading to detecting weak bosonin order to explore spin structure of the proton. KEK, RIKEN and Kyoto group is in charge ofthe electronics for the fast trigger electronics to pick up high momentum muon from W decay
and optical alignment system for geometrical alignment.

Team Leader
Toshiyuki KUBO (until June 2009)
Atsushi Taketani (since July 2009)
Members
Ken-ichiro YONEDA
Contract Researcher
Meiko UESAKAInternship
Yoshiyuki Aoki (Tokyo Metropolitan college of Aeronautical Engineering)
Masataka Masuyama (Tokyo Metropolitan college of Aeronautical Engineering)- 389 -

R�B� Research Di�isio�Acce�erator App�icatio�s Research Group （Group Director ： Ｔadashi KAMBARA）
Radiatio� Bio�o�� �ea�
1. Abstract
Radiation biology team studies various biological effects of fast heavy ions. It also develops
new technique to breed plants by heavy-ion irradiations. Fast heavy ions can produce dense andlocalized ionizations in matters along their tracks, in contrast to photons (X rays and gammarays) which produce randomly distributed isolated ionizations. These localized and dense
ionization can cause double-strand breaks of DNA in cells which are not easily repaired andresult in mutation more effectively than single-strand breaks. A unique feature of ourexperimental facility at the RIKEN Ring Cyclotron (RRC) is that we can irradiate living bodies
in atmosphere or in bottles since the delivered heavy-ion beams have energies high enough topenetrate deep in matter. This team utilizes a dedicated beam line (E5B) of the RRC to irradiate
cultivated cells, plants and animals with beams ranging from carbon to iron. Its researchsubjects cover physiological study of DNA repair, genome analyses of mutation, anddevelopment of mutation breeding of plants by heavy-ion irradiation. Some new cultivars havealready been brought to the market.
2. Major Research Subjects(1) Study on the biological effects by heavy-ion irradiation(2) Studies on ion-beam breeding and genome analysis(3) New medical application of heavy-ion beams
3. Summary of Research Activity
We study biological effects of fast heavy ions from the RIKEN Ring Cyclotron using 135
MeV/N C, N, Ne ions, 95 MeV/N Ar ions and 90 MeV/N Fe ions. We also develop breeding
technology of plants. Main subjects are:(1) Study and application of heavy-ion induced plant mutation
In contrast to X rays and gamma rays, fast heavy ions are found to be useful for plant breeding
since they only cause localized damage on DNA and can induce mutations more effectively withlower dosage. Our team utilizes beams of fast heavy ions from the RIKEN Ring Cyclotron todevelop heavy-ion breeding techniques. Genome analyses are performed to reveal the relation
between genotype and phenotype.
(2) Study of heavy ion-induced damage of DNA and its repair processes
We study the double-strand break of DNA induced by heavy-ion irradiation and its repair
processes. DNA double strand break (DSB) is characteristic to heavy-ion irradiation andconsidered to be the characteristic lesion responsible for its biological effects. Cells have twopathways to repair DSB, non-homologous end-joining(NHEJ) and homologous recombination (HR), and it is unknown how the two pathways are
involved in repairing the damage caused by heavy-ion irradiation. To elucidate it, we irradiatehigher vertebrate cells lacking DNA repair proteins with C, Ar, or Fe ions and analyze themwith colony formation assay and molecular biology methods.

Team Leader
Tomoko ABE- 390 -

Members
Tomonari HIRANO
Masako IZUMIYusuke KAZAMA
Mayu NAKAGAWA
Teruyo TSUKADA

Part-time Staff I
Hideo TOKAIRIN

Technical Staff I
Yoriko HAYASHITechnical Staff II
Sumie OHBU
Tomiko SHIBUKAWA

Visiting Scientists
Ryutaro AIDA (Natl. Inst. Floricult. Sci.)
Mari AMINO (Tokai University Hospital)
Chang-Hyu BAE (Sunchon Natl. Univ., Korea)
Yasuhiro CHIMI (JAEA)
Hiroyuki DAIMON (Osaka Pref. Univ.)
Ali FERJANI (Tokyo Gakugei Univ.)
Makoto FUJIWARA (Grad. Sch., Col. Arts Sci., Univ. of Tokyo)
Eitaro FUKATSU (Forest tree beeding Cet.)
Koji FURUKAWA (Mukoyama Orchids Co., Ltd.)
Yoshiya FURUSAWA (Natl. Inst. Radiol. Sci.)
Toshinari GODO (Botanic Gardens Toyama)
Misako HAMATANI (Hiroshima City Agric. Forest. Promot. Cen.)
Yasuhide HARA (Kanagawa Inst. Agric. Sci.)
Masanori HATASHITA (Wakasa Wan Energy Res. Cen.)
Atsushi HIGASHITANI (Grad. Sch. Life Sci., Tohoku Univ.)
Ryoichi HIRAYAMA (Natl. Inst. Radiol. Sci.)
Akiko HOKURA (Tokyo Denki Univ.)
Ichiro HONDA (Natl. Agric. Res. Cen.)
Mitsugu HORITA (Hokuren Agri. Res. Inst.)
Hiroyuki ICHIDA (Meiji Univ.)
Yuji ITO (Natl. Agric. Res. Cen., Hokkaido Region)
Akihiro IWASE (Grad. Sch. Engin., Osaka Pref. Univ.)
Hiroshi KAGAMI (Shizuoka Citrus Exp. Station)
Kensuke KAGEYAMA (Fac. Engin.,Saitama Univ.)
Takeshi KANAYA (Suntory Flowers, Ltd.)- 391 -

Si-Yong KANG (Dep. Rad. Plant Breed. Genet., KAERI, Korea)
Tomojirou KOIDE (Riken Vitamin Co., Ltd.)
Tsutomu KUBOYAMA (Ibaraki Univ.)
Norihiko MISHIMA (Fukuda Denshi Co., Ltd.)
Yutaka MIYAZAWA (Grad. Sch. Life Sci., Tohoku Univ.)
Kazumitsu MIYOSHI (Fac. Bioresour. Sci., Akita Pref. Univ.)
Toshikazu MORISHITA (Inst. Rad. Breeding, Natl. Inst. Agric. Res.)
Koji MURAI (Fukui Pref. Univ.)
Francesco MUSUMECI (Catania Univ.)
Daisuke NAKADA (Ela Medical Japan Co. Ltd.)
Koichiro NISHIKAWA (FLORSAIKA CIA. LTDA.)
Ishikawa NORITO (JAEA)
Mio OHNUMA (Inst. Mol. Cell. Biosci., Univ. Tokyo)
Norihiro OHTSUBO (Natl. Inst. Floricult. Sci.)
Fumihisa ONO (Grad. Sch. Natural Sci. & Tech., Okayama Univ.)
Tomo OOMIYA (Hokkaido Ornamental Plants Veg. Res. Cen.)
Kenji OSAWA (Nagano Agric. Res. Cen.)
Masaya SAKAI (Fukuda Denshi Co., Ltd.)
Kouichi SAKAMOTO (YUKIGUNI AGURI Co.,Ltd.)
Tadashi SATO (Grad. Sch. Life Sci., Tohoku Univ.)
Yoichi SATO (Riken Food Co., Ltd.)
Hiroaki SERIZAWA (Nagano Veg. Ornamental Crops Exp. Station)
Takiko SHIMADA (Res. Inst. Agric. Resour., Ishikawa Agric. Coll.)
Fumio SUGAWARA (Tokyo Univ. of Sci.)
Masao SUGIYAMA (Hokko Chem. Ind. Co., Ltd.)
Keita SUGIYAMA (Nat. Inst. Veg.Tea Sci.)
Ryuji SUGIYAMA (Ajinomoto, Co., INC.)
Kazunori SUZUKI (Plant Biotech. Inst. Ibaraki Agric. Cen.)
Masao SUZUKI (Natl. Inst. Radiol. Sci.)
Kenichi SUZUKI (Suntory Flowers, Ltd.)
Kunio SUZUKI (Technoflora, Co., Ltd.)
Hinako TAKEHISA (Natl. Inst. Agric. Sci.)
Sachie TANAKA (Tokai University)
Teruhiko TERAKAWA (Hokko Chem. Ind. Co., Ltd.)Ken TOKUHARA (Dogashima Orchid Cen.)
Masanori TOMITA (CRIEPI)
Hisashi TSUJIMOTO (Fac. Agri., Tottori Univ.)
Kozo TSUKADA (Nippon Veterinary and Life-sci. Univ.)
Masao WATANABE (Fac. Agri., Tohoku Univ.)
Takuji YOSHIDA (Takii Seed Co., Ltd.)
Koichiro YOSHIOKA (Tokai University Hospital)- 392 -

Research Fellows
Hideki ASAUMI (Ehime Agricultural Experiment Station)
Masataka CHAYA (Nagasaki Agr. Forest. Exp. Station)
Fumiko HIDAKA (Kagoshima Pref. Inst. for Agric. Dev.)
Hiroaki KISAKA (Ajinomoto, Co., INC.)
Tadanori MINO (Wadomari Cho Agr. Exp. Station)
Miyuki NISHI (Saga Agricultural Experiment Station)
Kyousuke NIWA (Hyogo Pref. Res. Inst.)
Tadahito OOTUBO (Wadomari Cho Agr. Exp. Station)
Eikou OOYABU (Saga Pref. Agr. Res. Cen.)
Takenori SAITO (Shizuoka Tea Exp. Station)
Tsukasa SHIRAO (Kagoshima Biotechnology Inst.)
Keiichi TAKAGI (Wakasa-wan Energy Research Center)
Kei-ichiro UENO (Kagoshima Biotechnology Inst.)
Naoji WAKITA (Wadomari Cho Agr. Exp. Station)
Yoshihide SAKITA (Wadomari Cho Agr. Exp. Station)

Consultant
Hiroyuki SAITO

Students
Junior Research Associate
Kiyoshi NISHIHARA (Grad. Sch. Frontier Sci., Univ. of Tokyo)

Student trainees
Kotaro ISHII (Grad. Sch. Frontier Sci., Univ. of Tokyo)
Liqiu MA (Grad. Sch. Sci. & Engin., Saitama Univ.)
Nobuhiro MAEDA (Grad. Sch. Eng., Osaka Pref. Univ.)
Yoshitaka MATSUMOTO (Grad. Sch. Medicine & Sch., Chiba Univ.)
Tomomi MORISHIMA (Tokyo Denki Univ.)
Saori TAKADA (Fac. Sci., Tokyo Univ. of Sci.)
Hiroki TAOKA (Fac. Sci., Tokyo Univ. of Sci.)
Wakiko YAMAOKA (Fac. Sci., Tokyo Univ. of Sci.)
Yuichi YOSHII (Fac. Sci., Tokyo Univ. of Sci.)- 393 -

R�B� Research Di�isio�Acce�erator App�icatio�s Research Group （Group Director ： Ｔadashi KAMBARA）
R� App�icatio�s �ea�
1. Abstract
RI Applications Team performs following researches at the heavy ion accelerators of RIBF: (1)With 14-MeV protons from the RIKEN AVF Cyclotron, we produce radioisotopes (RIs) for
research of chemistry, biology, medicine, pharmaceutical and environmental sciences. The
nuclides Zn-65, Cd-109 and Y-88 are delivered to Japan Radioisotope Association for charged
distribution to the general public in Japan. We also study the production and application ofshort-lived RIs. (2) We develop new technologies of mass spectrometry for the trace-element
analyses using accelerator technology and apply them to the scientific research fields, such ascosmochemistry, environmental science, archaeology and so on.
2. Major Research Subjects(1) Production of radioisotopes Zn-65, Cd-109 and Y-88 for charged distribution,(2) Research and development for new RI production at AVF cyclotron,(3) The development of trace element analysis, using the accelerator techniques, and its
application to geoscience and environmental science.
3. Summary of Research Activity
RI applications team utilizes RIBF heavy-ion accelerators for following research subjects:(1) Production of radioisotopes
Using a 14-MeV proton beam from the RIKEN AVF Cyclotron, we develop techniques of
production and application of various radio-isotopes (RIs) for research in chemistry, biology,
medicine, pharmaceutical and environmental sciences. We can produce RIs with wide range of
lifetimes as short as seconds. Long-life (> a few days) RIs are produced in a target which iscooled by water and He gas, and short-life RIs are produced at a gas-jet system where RI atoms
are recoiled out of thin foil targets, captured by KCl aerosols and transported to a hot lab by aflow of He carrier gas. These systems are in the same chamber in series and can operate
simultaneously with the same beam. Among the long-life RIs, Zn-65 (T1/2=244 days) andCd-109 (T1/2=463 days) have been delivered to Japan Radioisotope Association since October2007 for charged distribution to the general public in Japan. In addition, we started to deliver
Y-88 (T1/2=107 days) in February 2010.
(2) R/D for RI production
We work to improve production procedure of the present Zn-65, Cd-109 and Y-88 for stablesupply and better quality. We also develop production techniques for other RI species likeCe-139 (T1/2=138 days) which are demanded but lack supply sources. For the production ofshort-life RIs, the collection efficiency of gas-jet system has been optimized for Zr-89m(T1/2=4.16m), Nb-90m (T1/2=18.8s) and Nd-141m (T1/2=62s) nuclides.
(3) Trace element analyses with accelerator technologies
We have developed two new technologies of mass spectrometry for the trace-element analyses
as an application of accelerator technology to various fields such as cosmochemistry,
environmental science, archaeology and so on. On is a new type Accelerator Mass Spectrometry- 394 -

(AMS) at the RILAC equipped with an ECR ion source. This system is available for themeasurements of trace-elements (10-14-10-15level), and is expected to be especially effectible forthe measurements of low electron-affinity elements such as 26Al, 41Ca, 53Mn and so on. As apreliminary study, the ECR ion source system has been evaluated and the basic data have beenobtained for the detection and quantitative analysis of trace nuclides in archaeological samples(cinnabar) and functional metals. As another technology, we have attempted to customize amass spectrometer equipped with a stand-alone ECR ion source for analyses of elemental andisotopic abundances.

Team Leader
Tadashi KAMBARA
Members
Hiromitsu HABA
Kazuya TAKAHASHI
Shuichi ENOMOTO
Temporary Staff
Yutaka EZAKI
Visiting Scientists
Hiroshi HIDAKA (Fac. Sci., Hiroshima Univ.)
Hiroshi SHIMIZU (Fac. Sci., Hiroshima Univ.)
Miho TAKAHASHI (Tokyo Univ. Marine Sci. and Tech.)
Shigekazu YONEDA (Natl. Sci. Museum)
Tokuko WATANABE (Aoyama Gakuin Women's Junior College)
Masayoshi TODA (Tokyo Univ. Marine Sci. and Tech.)Research Consultants
Kuniko MAEDA
Part-time Staffs
Tatsuya URABE (Tokyo Univ. Marine Sci. and Tech.)Tomohiro OIKAWA (Tokyo Univ. Marine Sci. and Tech.)- 395 -

�IB� �e�e�rch Di�i�io���er �i�i�o� ��� I��u�tri�� �ooper�tio� Group （Group Director ： Ｔohru MOTOBAYASHI）
��er Support O��ice
1. Abstract
The RIKEN RI Beam Factory is the world preeminent facility providing the greatest
opportunities for scientific researches. The facility, completed its construction in 2007, hasstarted its full-scale operation in the end of the year 2008. It is our important mission to serve
for a broad range of application of a large variety of researchers so that we bring out the best
performance of the RI Beam Factory. We manage to facilitate the use of RI Beam Factory to theresearchers both inside and outside of RIKEN, to support experiments using the accelerator
complex, to exploit industrial application researches, and to promote the RI Beam Factory tointerested researchers
2. Major Research Subjects(1) Facilitation of the use of the RI Beam Factory(2) Support of experiments in the RI Beam Factory(3) Promotion of the RI Beam Factory to interested researchers
3. Summary of Research Activity
In order to facilitate the use of RI Beam Factory to the researchers both inside ad outside of
RIKEN, we have organized international Program Advisory Committee, consisting of world
leading scientists, to review proposals, purely based on their scientific merit and feasibility, inthe fields of nuclear physics (NP) and material-and-life science (ML). The NP- and ML-PAC
meetings are organized twice a year.
Another important activity is beam-time coordination of the PAC approved experiments andother development activities. The operation schedule of the RIBF accelerator complex ismanaged by our team taking into account strong demand of user’s experiments.

Team Leader
Toshimi SUDA
Members
Mieko KOGURE
Technical Staff I
Narumasa MIYAUCHI
Assistant
Tomoko IWANAMI
Yuri TSUBURAI- 396 -

�IB� �e�e�rch Di�i�io���er �i�i�o� ��� I��u�tri�� �ooper�tio� Group （Group Director ： Ｔohru MOTOBAYASHI）
I��u�tri�� �ooper�tio� Te��
1. Abstract
The scope of the industrial cooperation team includes industrial application of RIBF facility andresearch and development for industrial application of accelerator associated technologies.
2. Major Research Subjects
Distribution of radioisotopes Zn-65, Cd-109 and Y-88 produced at RIKEN AVF Cyclotron andinvestigation of novel industrial applications of the accelerator beam and its related technologies
3. Summary of Research Activity(1) Charged distribution of radioisotopes
At RIBF, various specific radioisotopes for research have been produced with the cyclotrons andused for various research projects. Since October 2007, we have distributed radioisotopes Zn-65
and Cd-109, which are produced by the RI application team at the AVF cyclotron, tononaffiliated users under a Material Transfer Agreement between Japan Radioisotope
Association and RIKEN. In 2009, we distributed total amount of 51.1MBq of Zn-65 and30MBq of Cd-109. In addition, we started distribution of Y-88 in February 2010.
(2) Feasibility study of RI-beam application in industries
To study feasibility of application of RI beam to industrial fields, research collaboration is being
arranged with a private company.

Team Leader
Tadashi KAMBARA
Members
Tomoko ABE
Hiroshige TAKEICHI
Visiting Scientists
Akira NAGANO (S. H. I. Examination & Inspection, LTD.)
Ryuji UEMOTO (S. H. I. Examination & Inspection, LTD.)
Hiroyuki UNO (S. H. I. Examination & Inspection, LTD.)- 397 -

㪩㪠㪙㪝㩷㪩㪼㫊㪼㪸㫉㪺㪿㩷㪛㫀㫍㫀㫊㫀㫆㫅㩷㪪㪸㪽㪼㫋㫐㩷㪤㪸㫅㪸㪾㪼㫄㪼㫅㫋㩷㪞㫉㫆㫌㫇㩷
1. Abstract
The Nishina Center for Accelerator-Based Science possesses one of the biggest accelerator
facilities in the world which consists of a heavy-ion linear accelerator and 5 cyclotrons.
Uranium ions are accelerated here only in Japan. Electron accelerators of microtron andsynchrotron-storage-ring also exist. Our function is to keep the radiation level in and around thefacility below the allowable limit and to control the exposure on the workers as low asreasonably achievable. We are also involved in the safety management of the Radioisotope
Center where many types of experiments are performed with sealed and unsealed radioisotopes.
2. Major Research Subjects(1)Safety management at radiation facilities of Nishina Center for Accelerator-Based Science(2)Safety management at Radioisotope Center(3)Radiation shielding design and development of accelerator safety systems
3. Summary of Research Activity
Our most important task is to keep the personnel exposure as low as reasonably achievable, andto prevent an accident. Therefore, we daily patrol the facility, measure the ambient dose rates,
maintain the survey meters, shield doors and facilities of exhaust air and wastewater, replenish
the protective supplies, and manage the radioactive waste. Advice, supervision and assistance atmajor accelerator maintenance works are also our task.
A new accelerator interlock system was installed at RIBF building for the newly built electron
machines. We extend the radiation safety interlock system (HIS) for heavy-ion accelerators tomeet the change of experiment area at RIBF building where new detectors are installed. The
suffocation-safety interlock system is working at the BigRIPS tunnel of RIBF accelerator
building where huge amount of liquid He is used for superconducting magnets. Since a new
injector linac, RILAC2, is installed in the AVF vault, the radiation safety interlock system for
Nishina building is also modified.

Head
Yoshitomo UWAMINO
Members
Hisao SAKAMOTO
Rieko HIGURASHI (HIRUNUMA)
Technical Staff I
Atsuko AKASHIO
Assistant
Tomomi OKAYASU- 398 -

Contract Officer
Hiroki MUKAI
Satoshi HASHIGUCHI
Hiroyuki FUKUDA
Special Temporary Employee
Shin FUJITA
Visiting Scientists
Koji OHISHI
Secretary
Tsutomu YAMAKI
Kazushiro NAKANO
Kimie IGARASHI
Satomi IIZUKA
Hiroko AISO

- 399 -

㪚㪼㫅㫋㪼㫉㩷㪽㫆㫉㩷㪥㫌㪺㫃㪼㪸㫉㩷㪪㫋㫌㪻㫐㪃㩷㪞㫉㪸㪻㫌㪸㫋㪼㩷㪪㪺㪿㫆㫆㫃㩷㫆㪽㩷㪪㪺㫀㪼㫅㪺㪼㪃㩷㪬㫅㫀㫍㪼㫉㫊㫀㫋㫐㩷㫆㪽㩷㪫㫆㫂㫐㫆㪅㩷
1. Abstract
The Center for Nuclear Study (CNS) aims to elucidate the nature of nuclear system byproducing the characteristic states where the Isospin, Spin and Quark degrees of freedom play
central roles. These researches in CNS lead to the understanding of the matter based on common
natures of many-body systems in various phases. We also aim at elucidating the explosion
phenomena and the evolution of the universe by the direct measurements simulating nuclear
reactions in the universe. In order to advance the nuclear science with heavy-ion reactions, wedevelop AVF upgrade, CRIB and SHARAQ facilities in the large-scale accelerators laboratories
RIBF. We promote collaboration programs at RIBF as well as RHIC-PHENIX and ALICE-LHC
with scientists in the world, and host international meetings and conferences. We also provide
educational opportunities to young scientists in the heavy-ion science through the graduate
course as a member of the department of physics in the University of Tokyo and through hosting
the international summer school.
2. Major Research Subjects(1) Accelerator Physics(2) Nuclear Astrophysics(3) Nuclear spectroscopy of exotic nuclei(4) Quark physics(5) Spin Physics(6) Nuclear Theory(7) SHARAQ project
3. Summary of Research Activity(1) Accelerator Physics
One of the Major tasks of the accelerator group is the AVF upgrade project which includes
development of ion sources, upgrading the AVF cyclotron of RIKEN and the beam line to CRIB.
A new heavy ion ECR source of CNS that use super-conducting magnet was successfully
installed to the AVF cyclotron, and has been used to provide a variety heavy ion beams. Two
CNS ECR sources now provide all the beams for the AVF cyclotron and support not only CRIB
experiments but also a large number of RIBF experiments. A charge-breeding ECR source isalso under development.
Two major works were advanced for upgrading the AVF cyclotron. One is the detailed design
study of the central region of the cyclotron, which remedies insufficiencies for the transmissionof the heavy ion beams through the cyclotron. A new central module will be made following
the design. The second is a successful acceleration of heavy ion beams up to 11 Mev/u which
was about 9.5 MeV/u before. Following the detailed simulation studies of the heavy ion beams
through the cyclotron, beam acceleration tests were successfully performed for 16O and 6Li
beams. These beams will be provided to new experimental projects at CRIB.
A non-destructive beam monitor was also successfully developed and installed just in front of
the CRIB production target. It showed a sensitivity of about a few nA. This new beam monitor
will become a powerful tool for all the RIBF facility.
(2) Nuclear Astrophysics
Major activity of the nuclear astrophysics group is to investigate experimentally nucleosynthesis- 400 -

of the universe, specifically of explosive phenomena in the universe such as novae andsupernovae. High-intensity RI beams of light nuclei from the CNS low-energy RI beam
separator CRIB provides a good opportunity to study stellar nuclear reactions under explosive
conditions both by the direct method as well as by indirect methods. The research programs
include investigations of α-induced stellar reactions on 7Li, 14O and 21Na. The beta decay of46
Cr was also studied to learn the Gamow-Teller Transitions. Some beam developments weremade for new RI beams, and an active target was also designed for studies of stellar reactions
with low-cross sections.
Some technological development for the beam line as well as for the Wienfilter of CRIB weremade in the past year.
(3) Nuclear structure of exotic nuclei
The NUSPEQ (NUclear SPectroscopy for Extreme Quantum system) group studies exotic
structures in high-isospin and/or high-spin states in nuclei. The CNS GRAPE (Gamma-Ray
detector Array with Position and Energy sensitivity) is a major apparatus for high-resolution
in-beam gamma-ray spectroscopy. In 2009, the following progress has been made.
Neutron-rich nuclei around island-of-inversion have been studied by using nucleon transfer
and inelastic scattering where the final states are identified by measuring de-excited
gamma-rays. Several candidates of cluster states in 12Be was found especially for odd-spinstates suggesting asymmetric cluster configuration.
New high-spin states in 49-51Ti populated by fusion reactions of an RI beam have been found,which gives information on the N=28 shell gap and the single particle energies in the fp-shell..
High-spin states in A〜40 mass region were studied via 18O+26Mg fusion evaporation reactions.
A superdeformed rotational band up to 12+ state was observed in 40Ar. This finding indicatesthe presences of the N=22 and Z=18 superdeformed shell structure in this region. High-spinstates of 107In was studied via 58Ni(52Cr,3p) reaction. A rotational cascade consisting ten
gamma-ray transitions was observed. The band exhibits the features typical for smoothterminating bands in A〜100 mass region.
Upgrade of the readout system of the CNS GRAPE has started, where digital pulse data taken
by sampling ADCs are analyzed by FPGAs on boards.

(4) Quark Physics
Main goal of the quark physics group is to understand the properties of hot and dense nuclear
matter created by colliding heavy nuclei at relativistic energies. The group has been involvedin the PHENIX experiment at Relativistic Heavy Ion Collider (RHIC) at Brookhaven National
Laboratory, and in the ALICE experiment at Large Hadron Collider (LHC) at CERN. In 2009,
LHC finally started making collisions.
As for PHENIX, the group has been concentrating on the physics analysis with leptons andphotons, which include direct photon yield at low transverse momentum using thevirtual-gamma method, neutral pion yield at high transverse momentum as a function of
azimuthal angle from the reaction plane in Au+Au collisions, J/ψ production in ultra-peripheral
Au+Ai collisions.
As for ALICE, the group has been committing the commissioning of the Transition Radiation
Detector (TRD), and calibration and performance study of Time Projection Chamber (TPC).
The group has been leading development of forward calorimeter for a possible future upgrade.
R&D of gas electron multiplier (GEM) and related techniques has been continuing. Time- 401 -

projection chamber, to be used as an active target at RIBF experiments, was developed.
Resistive GEM, which utilizes resistive anodes, has been developed.
(6) Nuclear Theory
The nuclear theory group has been promoting the RIKEN-CNS collaboration project onlarge-scale nuclear structure calculations since 2001 and maintaining its parallel computing
cluster. In 2009, we developed the effective interactions of various mass region based on thelarge-scale shell model calculation technique and discussed the "shell evolution" and the role oftensor force quantitatively in exotic nuclei, such as 17C, 48Ca, N=50 isotones, Sm isotopes and soon.
(7) SHARAQ project
Construction of the SHARAQ spectrometer and the dedicated high-resolution beamline arecoming to the final phase. The magnetic field distribution in dipole magnets, D1 and D2, wereprecisely measured with the search coil method. A major part of the beamline has been
constructed. Cathode readout drift chambers for tracking detectors at the SHARAQ focal plane
have been fabricated in GANIL and installed to SHARAQ in December 2008. It was also foundthat Low-pressure multiwire drift chambers (LP-MWDC) developed for beamline tracking
detectors works well under pressure as low as 10 kPa with an isobuthane gas.

Director
Takaharu OTSUKA
Scientific Staff
Susumu SHIMOURA (Professor)
Shigeru KUBONO (Professor)
Hideki HAMAGAKI (Associate Professor)
Tomohiro UESAKA (Associate Professor)
Eiji IDEGUCHI (Lecturer)
Takahiro KAWABATA (Research Associate (- Jan. 31, 2009))
Hidetoshi YAMAGUCHI (Research Associate)
Shin'ichiro MICHIMASA (Research Associate)
Taku GUNJI (Research Associate)
Shinsuke OTA (Research Associate)
Guest Scientists
Toshio SUZUKI (Guest Professor, Nihon Univ.)
Toshinori MITSUMOTO (Guest Associate Professor, Sumitomo Heavy Industries, Ltd.)Technical Staff
Yukimitsu OHSHIRONorio YAMAZAKI- 402 -

Technical Assistants
Shin-ichi WATANABE
Hiroshi KUREI
Hideaki NINOMIYA
Akira YOSHINO
Shoichi YAMAKA
Post Doctoral Associates
Shinsuke OTA (-Mar. 31, 2009)
Takashi ABE (-Mar. 31, 2009)
Yohei SHIMIZU (-Dec. 31, 2010)
Kosuke NAKANISHI (-June 30, 2009)
Takashi HASHIMOTO
Yasuo WAKABAYASHI (-Mar. 31, 2009)
Yuji TSUCHIMOTO (Mar. 25, 2009 -)Akito SAITO
Toru YOSHIDA (April 1, 2009 -)Megumi NIIKURA (-April 30, 2009 )Graduate Students
Megumi NIIKURA (-Mar. 31, 2009)
Yuhei MORINO (-Mar. 31, 2009)
Satoshi SAKAGUCHI (-Mar. 31, 2009)
Yoshiko SASAMOTO
Yorito YAMAGUCHI
Yoki ARAMAKI
Nguyen Binh DAM
Satoshi SANO
Seiya HAYAKAWADavid. M KAHL
Akihisa TAKAHARA
Yuzo KURIHARA (-Mar. 31, 2009)
Hiroyuki MIYA
Ryoji AKIMOTO
Yasuto HORI
Kenshi OKADA (-Mar. 31, 2009)
Hiroshi TOKIEDA
Tomoya TSUJI
Shintaro GO
Shoichiro KAWASE- 403 -

Administration Staff
Midori HIRANO
Ikuko YAMAMOTO
Takako ENDO
Yukino KISHI
Toshiko ITAGAKI
Yuko SOMA- 404 -

㪫㪦㪩㪠㪡㪠㪥㩷㩿㪫㫆㪻㪸㫀㪄㪩㪠㪢㪜㪥㩷㪡㫆㫀㫅㫋㩷㪠㫅㫋㪼㫉㫅㪸㫋㫀㫆㫅㪸㫃㩷㪧㫉㫆㪾㫉㪸㫄㩷㪽㫆㫉㩷㪥㫌㪺㫃㪼㪸㫉㩷㪧㪿㫐㫊㫀㪺㫊㪀㩷㪫㪼㫉㫄㩷
1. Abstract
University of Tokyo and RIKEN agreed to corporate with each other in the field of nuclear
physics and established Todai-RIKEN Joint International Program for Nuclear Physics(TORIJIN) in June 2006. The aim of this organization is to promote the international
collaborations, such as JUSTIPEN (Japan-US Theory Institute for Physics with Exotic Nuclei)
and EFES (International Research Network for Exotic Femto Systems). JUSTIPEN was
launched in June 2006 in order to facilitate collaborations between U.S. and Japanese scientists
whose main research thrust is in the area of the physics of exotic nuclei. More than 40 nuclear
scientists in U.S. have visited Japan in three years, and many collaborations are established.
EFES was selected as one of the Core-to-Core Programs of Japan Society for the Promotion of
Science (JSPS). This is the program to send Japanese nuclear scientists to U.S., Germany,
France, Italy, Norway, and Finland and to promote the international collaborations in the field of
nuclear study. Many joint workshops were held with the partner countries.
2. Main activities
Promote the international collaborations of both theoretical and experimental nuclear
physicists under JUSTIPEN and EFES programs.
3. Summary of Research Activity
Under the JUSTIPEN program, many nuclear scientists visited in this fiscal year andcollaborations are established. Under the EFES program, we have carried out four types ofactivities: initiating the collaboration projects, organizing seminars with partner courtiers,
sending researchers abroad, and sending/inviting young scientists to the summer schools.
Regarding the collaborative works, we have carried out seven projects. Many experimentalists
and theoreticians have been sent abroad. As for the joint workshops, we have organized six
workshops and all of them were quite fruitful. Also, young scientists have been sent to partnercountries for educational purpose and starting collaborations. As for the summer school,
Japanese graduate students have been sent to the summer schools in Germany, Italy, and USA,and we have invited students to CNS-EFES summer school from the partner countries.

LeaderTakaharu OTSUKA (University of Tokyo)
Vice leader
Tohru MOTOBAYASHI (RIKEN)
Members
Susumu SHIMOURA (University of Tokyo),
Hiroyoshi SAKURAI (RIKEN),
Takashi NAKATSUKASA (RIKEN),
Tomohiro UESAKA (University of Tokyo),
Naoyuki ITAGAKI (University of Tokyo)- 405 -

VI. LIST OF PUBLICATIONS& PRESENTATIONRIKEN Nishina
Center for Accelerator-Based Science (RNC)
RNC
Publications
Publications[Journal](Original Papers) *Subject to Peer Review
Adare A., Akiba Y., Aoki K., Asai J., Bazilevsky A. V.,
Bunce G. M., Deshpande A., Enyo H., Fields D. E.,
Fox B., Fujiwara K., Fukao Y., Goto Y., Gross P. M.,
Hasuko K., Heuser J. M., Horaguchi T., Ichihara T.,
Imai K., Inoue Y., Ishihara M., Jinnouchi O., KamiharaN., Kaneta M., Kanoh H., Kawall D., Kiyomichi A.,
Kobayashi H., Kurita K., Mao Y., Murata J., Nakagawa
I., Nakano K., Onishi H., Okada H., Okada K., Rykov V.
L., Saito N., Sato H., Shibata T., Shoji K., Tabaru T.,
Taketani A., Tanida K., Togawa M., Tojo J., Torii H.,
Wagner M. M., Watanabe Y., Xie W., and Yokkaichi
S.: “Cold Nuclear Matter Eﬀects on J/ψ Production as Constrained by Deuteron-Gold Measurements at√
sNN = 200 GeV”, Phys. Rev. C 77, 024912-1–02491215 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K., Fukao
Y., Goto Y., Gross P. M., Hachiya T., Hasuko K., Heuser
J. M., Horaguchi T., Ichihara T., Imai K., Inoue Y.,
Ishihara M., Jinnouchi O., Kajihara F., Kamihara N.,
Kaneta M., Kanoh H., Kawall D., Kiyomichi A., Kurita
K., Mao Y., Murata J., Nakagawa I., Nakano K., Onishi
H., Okada H., Okada K., Rykov V. L., Saito N., Sato H.,
Shibata T., Shoji K., Tabaru T., Taketani A., Tanida K.,
Togawa M., Tojo J., Torii H., Tsuchimoto Y., Wagner
M. M., Watanabe Y., Xie W., and Yokkaichi S.: “Quantitative Constraints on the Transport Properties of Hot
Partonic Matter from Semi-Inclusive Single High Transverse Momentum Pion Suppression in Au+Au Collisions√
at sNN = 200 GeV”, Phys. Rev. C 77, 064907-1–
064907-12 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K., Fukao
Y., Goto Y., Gross P. M., Hachiya T., Hasuko K., Heuser
J. M., Horaguchi T., Ichihara T., Imai K., Inoue Y.,
Ishihara M., Jinnouchi O., Kajihara F., Kamihara N.,
Kaneta M., Kanoh H., Kawall D., Kiyomichi A., Kurita
K., Mao Y., Murata J., Nakagawa I., Nakano K., Onishi
H., Okada H., Okada K., Rykov V. L., Saito N., Sato H.,
Shibata T., Shoji K., Tabaru T., Taketani A., Tanida K.,
Togawa M., Tojo J., Torii H., Tsuchimoto Y., Wagner
M. M., Watanabe Y., Xie W., and Yokkaichi S.: “Dihadron azimuthal correlations in Au+Au collisions at√
sNN = 200 GeV”, Phys. Rev. C 78, 014901-1–01490142 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bazilevsky A. V.,
Bunce G. M., Deshpande A., Enyo H., Fields D. E.,
Fox B., Fujiwara K., Fukao Y., Goto Y., Gross P. M.,
Hachiya T., Hasuko K., Heuser J. M., Horaguchi T.,
Ichihara T., Imai K., Inoue Y., Ishihara M., Jinnouchi

O., Kajihara F., Kamihara N., Kaneta M., Kanoh H.,
Kawall D., Kiyomichi A., Kobayashi H., Kurita K., Mao
Y., Murata J., Nakagawa I., Nakano K., Onishi H.,
Okada H., Okada K., Rykov V. L., Saito N., Sato H.,
Shibata T., Shoji K., Tabaru T., Taketani A., Tanida
K., Togawa M., Tojo J., Torii H., Tsuchimoto Y.,
Wagner M. M., Watanabe Y., Xie W., and Yokkaichi
S.: “Charged hadron multiplicity ﬂuctuations in Au+Au√
and Cu+Cu collisions from sNN = 22.5 to 200 GeV”,
Phys. Rev. C 78, 044902-1–044902-15 (2008).
Afanasiev S., Akiba Y., Aoki K., Bunce G. M., DeshpandeA., Enyo H., Fields D. E., Fukao Y., Goto Y., Gross P.
M., Hachiya T., Hasuko K., Heuser J. M., Horaguchi
T., Ichihara T., Imai K., Ishihara M., Jinnouchi O.,
Kajihara F., Kamihara N., Kaneta M., Kiyomichi A.,
Kurita K., Murata J., Onishi H., Okada H., Okada K.,
Rykov V. L., Saito N., Sato H., Shibata T., Shoji K.,
Tabaru T., Taketani A., Tanida K., Togawa M., TojoJ., Torii H., Tsuchimoto Y., Wagner M. M., WatanabeY., Xie W., and Yokkaichi S.: “Source breakup dynam√
ics in Au+Au Collisions at sNN =200 GeV via threedimensional two-pion source imaging”, Phys. Rev. Lett.
100, 232301-1–232301-6 (2008).
Afanasiev S., Akiba Y., Aoki K., Bunce G. M., DeshpandeA., Enyo H., Fields D. E., Fukao Y., Goto Y., Gross P.
M., Hachiya T., Hasuko K., Heuser J. M., Horaguchi
T., Ichihara T., Imai K., Ishihara M., Jinnouchi O.,
Kajihara F., Kamihara N., Kaneta M., Kiyomichi A.,
Kurita K., Murata J., Onishi H., Okada H., Okada K.,
Rykov V. L., Saito N., Sato H., Shibata T., Shoji K.,
Tabaru T., Taketani A., Tanida K., Togawa M., Tojo J.,
Torii H., Tsuchimoto Y., Wagner M. M., Watanabe Y.,
Xie W., and Yokkaichi S.: “Particle-species dependent
modiﬁcation of jet-induced correlations in Au+Au col√lisions at sNN = 200 GeV”, Phys. Rev. Lett. 101,
082301-1–082301-6 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K., Fukao
Y., Goto Y., Gross P. M., Horaguchi T., Ichihara T.,
Imai K., Inoue Y., Ishihara M., Jinnouchi O., KamiharaN., Kaneta M., Kanoh H., Kawall D., Kiyomichi A.,
Kurita K., Mao Y., Murata J., Nakagawa I., Nakano
K., Onishi H., Okada H., Okada K., Rykov V. L.,
Saito N., Shibata T., Shoji K., Tabaru T., Taketani A.,
Tanida K., Togawa M., Tojo J., Torii H., Wagner M.
M., Watanabe Y., Xie W., and Yokkaichi S.: “J/ψ Pro√
duction in sNN = 200 GeV Cu+Cu Collisions”, Phys.
Rev. Lett. 101, 122301-1–122301-6 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Dairaku S., Deshpande A., Enyo H., Fields D. E.,
Fujiwara K., Fukao Y., Goto Y., Gross P. M., Horaguchi
T., Ichihara T., Ichimiya R., Imai K., Inoue Y., Ishihara
M., Jinnouchi O., Kametani S., Kamihara N., Kaneta
M., Kanoh H., Kawall D., Kiyomichi A., Kurita K.,
Kurosawa M., Li Z., Mao Y., Murata J., Nakagawa I.,- 407 -

1

Nakano K., Onishi H., Okada H., Okada K., Onuki Y.,
Rykov V. L., Saito N., Sakashita K., Shibata T., Shoji
K., Tabaru T., Taketani A., Tanida K., Togawa M.,
Tojo J., Torii H., Wagner M. M., Watanabe Y., Xie W.,
and Yokkaichi S.: “Onset of π 0 suppression studied in√
Cu+Cu collisions at sNN = 22.4, 62.4, and 200 GeV”,
Phys. Rev. Lett. 101, 162301-1–162301-6 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K.,
Fukao Y., Goto Y., Gross P. M., Hachiya T., Hasuko K.,
Heuser J. M., Horaguchi T., Ichihara T., Imai K., Inoue
Y., Ishihara M., Jinnouchi O., Kajihara F., KamiharaN., Kaneta M., Kanoh H., Kawall D., Kiyomichi A.,
Kurita K., Mao Y., Murata J., Nakagawa I., Nakano K.,
Onishi H., Okada H., Okada K., Rykov V. L., Saito N.,
Sato H., Shibata T., Shoji K., Tabaru T., Taketani A.,
Tanida K., Togawa M., Tojo J., Torii H., Tsuchimoto Y.,
Wagner M. M., Watanabe Y., Xie W., and Yokkaichi S.:“Suppression pattern of neutral pions at high transverse√
momentum in Au+Au collisions at sNN = 200 GeV
and constraints on medium transport coeﬃcients”, Phys.
Rev. Lett. 101, 232301-1–232301-7 (2008).
Asahi K., Ueno H., Shimada K., Nagatomo T., Yoshimi
A., Nagae D., Kameda D., Uchida M., Inoue T.,
Hatakeyama N., Kagami S., Hasama Y., Suzuki K.,
Murata J., Kawamura H., Narita K., and Ishihara M.:“Nuclear Structure Studies with Polarized Radioactive
Beams”, AIP Conf. Proc. 1149, 90–99 (2009).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K., Fukao
Y., Goto Y., Gross P. M., Horaguchi T., Ichihara T.,
Imai K., Inoue Y., Ishihara M., Jinnouchi O., KamiharaN., Kaneta M., Kanoh H., Kawall D., Kiyomichi A.,
Kurita K., Mao Y., Murata J., Nakagawa I., Nakano K.,
Onishi H., Okada H., Okada K., Rykov V. L., Saito N.,
Shibata T., Shoji K., Tabaru T., Taketani A., Tanida K.,
Togawa M., Tojo J., Torii H., Wagner M. M., WatanabeY., Xie W., and Yokkaichi S.: “Dilepton mass spectra√in p+p collisions at s = 200 GeV and the contribution
from open charm”, Phys. Lett. B 670, 313–320 (2009).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Dairaku S., Deshpande A., Enyo H., Fields D. E.,
Fujiwara K., Fukao Y., Goto Y., Gross P. M., Horaguchi
T., Ichihara T., Ichimiya R., Imai K., Ishihara M.,
Kametani S., Kamihara N., Kawall D., Kurita K.,
Kurosawa M., Li Z., Mao Y., Murata J., Nakagawa I.,
Nakano K., Okada H., Okada K., Onuki Y., Rykov V. L.,
Saito N., Sakashita K., Shibata T., Shoji K., Taketani
A., Tanida K., Togawa M., Torii H., Watanabe Y., Xie
W., and Yokkaichi S.: “Inclusive cross section and double helicity asymmetry for π 0 production in p + p colli√
sions at s = 62.4 GeV”, Phys. Rev. D 79, 012003-1–
012003-11 (2009).
Suda T., Wakasugi M., Emoto T., Ito S., Kurita K., Tamae

T., Wang S., and Yano Y.: “First demonstration of electron scattering using a novel target developed for shortlived nuclei”, Phys. Rev. Lett. 102, No. 10, pp. 1025011–102501-4 (2009).
[Book • Proceedings
Proc.](Others)
Fukunishi N., Fujimaki M., Watanabe T., Kumagai K.,
Komiyama M., Watanabe H., Goto A., Hasebe H.,
Higurashi Y., Ikezawa E., Kageyama T., Kamigaito
O., Kase M., Kuboki H., Kidera M., Nagase M., Maie
T., Nakagawa T., Ohnishi J., Okuno H., SakamotoN., Sekiguchi K., Suda K., Suzuki H., Wakasugi M.,
Watanabe Y., Yokouchi S., Yano Y., and Yamada K.:“Operating experience with the RIKEN Radioactive Isotope Beam Factory”, Proceedings of the 2009 Particle
Accelerator Conference (PAC09), Vancouver, Canada,
2009–5, PAC09 Editor, Vancouver, pp. MO3GRI0-1–
MO3GRI0-5 (2009).

Oral Presentations
Oral Presentations((International) Conference etc.)
Takeuchi S., Shimoura S., Motobayashi T., Akiyoshi H.,
Ando Y., Aoi N., Fulop Z., Gomi T., Higurashi Y.,
Hirai M., Iwasa N., Iwasaki H., Iwata Y., Kobayashi H.,
Kurokawa M., Liu Z., Minemura T., Ozawa S., Sakurai
H., Serata M., Teranishi T., Yamada K., Yanagisawa
Y., and Ishihara M.: “Isobaric analog state of 14 Be”,
RIKEN-CNS RIBF International Workshop “Correlation and Condensation: New Features in Loosely Boundand Unbound Nuclear States”, Wako, Dec. (2005).
Fukunishi N., Fujimaki M., Watanabe T., Kumagai K.,
Komiyama M., Watanabe H., Goto A., Hasebe H.,
Higurashi Y., Ikezawa E., Kageyama T., Kamigaito
O., Kase M., Kuboki H., Kidera M., Nagase M., Maie
T., Nakagawa T., Ohnishi J., Okuno H., SakamotoN., Sekiguchi K., Suda K., Suzuki H., Wakasugi M.,
Watanabe Y., Yokouchi S., Yano Y., and Yamada K.:“Operating experience with the RIKEN Radioactive Isotope Beam Factory”, 23rd Particle Accelerator Conference (PAC09), Vancouver, Canada, May (2009).
Motizuki Y., Takahashi K., Nakai Y., Makishima K.,
Bamba A., Yano Y., Igarashi M., Motoyama H.,
Kamiyama K., Suzuki K., and Imamura T.: “A Dome
Fuji ice core recording both supernovae and solar cycles”, 2nd International Symposium on Dome Fuji Ice
Core and Related Topics, (National Institute of Polar
Research), Tachikawa, Nov. (2009).
((Domestic)Conference)
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
: “RI
”,
5
/ 33
,(

- 408 -

2

),
,

,
,

,
,

2009
,

,
”,

),

,
,
,
SQUID

6
,8

,8

,

,5

(2008).
,,: “”,(2009).
,
: “

,

,(
(2009).

- 409 -3

RNC
Theoretical
Physics Laboratory

Publications
Publications[Journal](Original Papers)*Subject to Peer Review
Ishida M. and Igi K.: “Test of the universal rise of hadronic
total cross sections at super-high energies”, Eur. Phys.
J. C 52, 357–362 (2007).
Takimi T.: “Relationship between various supersymmetriclattice models”, J. High Energy Phys. 0707, 010-1–01025 (2007).
Loaiza-Brito O. and Oda K.: “Eﬀects of brane-ﬂux transition on black holes in string theory”, J. High Energy
Phys. 0708, 002-1–002-22 (2007).
Hanada M. and Nishioka T.: “Cascade of GregoryLaﬂamme Transitions and U(1) Breakdown in Super
Yang-Mills”, J. High Energy Phys. 0709, 012-1–012-14(2007).
Kawamura Y., Kinami T., and Oda K.: “Orbifold family uniﬁcation”, Phys. Rev. D 76, 035001-1–035001-11(2007).
Hanada M., Nishimura J., and Takeuchi S.: “Nonlatticesimulation for supersymmetric gauge theories in one dimension”, Phys. Rev. Lett. 99, 161602-1–161602-4(2007).
Ohta K. and Takimi T.: “Lattice formulation of a twodimensional topological ﬁeld theory”, Prog. Theor.
Phys. 117, No. 2, pp. 317–345 (2007).
Damgaard P. and Fukaya H.: “Partially quenched chiralperturbation theory in the epsilon-regime”, Nucl. Phys.
B 793, 160–191 (2008).
Aoki S., Chiu T., Fukaya H., Hashimoto S., Hsieh T.,
Kaneko T., Matsufuru H., Noaki J., Ogawa K., Onogi
T., and Yamada N.: “Topological susceptibility in twoﬂavor lattice QCD with exact chiral symmetry”, Phys.
Lett. B 665, 294–297 (2008).
Hanada M., Anagnostopoulos K., Nishimura J.,
and Takeuchi S.: “Monte Carlo studies of supersymmetric matrix quantum mechanics with sixteen
supercharges at ﬁnite temperature”, Phys. Rev. Lett.
100, 021601-1–021601-4 (2008).
Baba Y., Ishibashi N., and Murakami K.: “Light-conegauge superstring ﬁeld theory and dimensional regularization”, J. High Energy Phys. 10, 035-1–035-17 (2009).
Baba Y., Ishibashi N., and Murakami K.: “Light-conegauge string ﬁeld theory in noncritical dimensions”, J.
High Energy Phys. 12, 010-1–010-24 (2009).
Gibbons G. W., Hashimoto K., and Hirano S.: “Gravitational Dual of Tachyon Condensation”, J. High Energy
Phys. 0909, 100-1–100-7 (2009).
Hashimoto K.: “Holographic Nuclei: supersymmetric examples”, J. High Energy Phys. 0912, 065-1–065-9(2009).
Kadoh D., Sugino F., and Suzuki H.: “Lattice formulationof 2D N = (2, 2) SQCD based on the B model twist”,
Nucl. Phys. B 820, No. 1-2, pp. 99–115 (2009).
Ishida M. and Igi K.: “Universal Rise of Hadronic Total
Cross Sections based on Forward pi p and anti-pp(pp)Scatterings”, Phys. Lett. B 670, 395–398 (2009).
Igi K. and Ishida M.: “Test of Universal Rise of Hadronic
Total Cross Sections based on pi p, Kp and anti-p p,pp
Scatterings”, Phys. Rev. D 79, 096003-1–096003-15(2009).
Hanada M. and Kanamori I.: “Lattice study of twodimensional N = (2, 2) super Yang-Mills theory at large
N ”, Phys. Rev. D 80, 065014-1–065014-12 (2009).
Kishimoto I. and Takahashi T.: “Numerical evaluation ofgauge invariants for a-gauge solutions in open string ﬁeld
theory”, Prog. Theor. Phys. 121, No. 4, pp. 695–710(2009).
Kishimoto I. and Takahashi T.: “Vacuum structurearound identity-based solutions”, Prog. Theor. Phys.
122, No. 2, pp. 385–399 (2009).
Hashimoto K., Sakai T., and Sugimoto S.: “Nuclear Forcefrom String Theory”, Prog. Theor. Phys. 122, No. 2,
pp. 427–476 (2009).
Baba Y., Ishibashi N., and Murakami K.: “Light-conegauge NSR strings in noncritical dimensions”, J. HighEnergy Phys. 1001, 119-1–119-19 (2010).
Kadoh D. and Suzuki H.: “SUSY WT identity in a lattice
formulation of 2D N = (2, 2) SYM”, Phys. Lett. B 682,
466–471 (2010).
Kadoh D. and Suzuki H.: “Supersymmetric nonperturbative formulation of the WZ model in lower dimensions”,
Phys. Lett. B 684, No. 2-3, pp. 167–172 (2010).
(Review)
Ezawa Z. and Tsitsishvili G.: “Quantum Hall ferromagnets”, Rep. Prog. Phys. 72, 086502-1–086502-32(2009).

Oral Presentations
Oral Presentations((International) Conference etc.)
Kishimoto I. and Takahashi T.: “Numerical evaluation ofgauge invariants for a-gauge solutions in open string ﬁeld
theory”, 2nd International Conference on String Field
Theory and Related Aspects, (Steklov Mathematical Institute), Moscow, Russia, Apr. (2009).
Kishimoto I. and Takahashi T.: “On identity based solutions in open string ﬁeld theory”, APCTP Focus Program on Current Trends in String Field Theory, Pohang,
Korea, Dec. (2009).
((Domestic)Conference): “Gravity dual of tachyon condensation”,
64,(),, 3 (2009).
,
,
:
2009
,
(
),
, 3 (2009).
,: “Numerical evaluation of gauge invariants for a-gauge solutions in open string ﬁeld theory”,
2009,, 3 (2009).
KEK- 410 -

1

,: “Vacuum structure around identity
based solutions”,,),, 7 (2009).
(
: “
”,
,(
),
, 7 (2009).
: “Holographic QCD and Nuclear Force”, KEK,,8(2009).
: “Gravity Dual of Nuclei”,
2009,, 9 (2009).
,,: “light-cone
gauge
”,
2009
,
, 9 (2009).
,,: “light-cone gauge
”,
2009
,
,
9
(2009).
,
: “
”,
2009
,
,
9
(2009).
: “
”,
,(
),
, 12 (2009).

- 411 -

2

Theoretical
RNC Nuclear Physics Laboratory
Publications
Publications[Journal](Original Papers) *Subject to Peer Review
Yabana K., Nakatsukasa T., and Ito M.: “Time-dependent
description for nuclear reaction dynamics in the continuum”, Few Body Syst. 43, 247–253 (2008).
Barbieri C. and Van Neck D.: “Ab-initio Green’s Functions Calculations of Atoms”, AIP Conf. Proc. 1120,
104–108 (2009).
Yoshida K.: “Monopole Modes of Excitation in Deformed
Neutron-rich Mg Isotopes”, AIP Conf. Proc. 1165,
162–164 (2009).
Nakatsukasa T., Inakura T., and Yabana K.: “Finite amplitude method and systematic studies of photoresponse
in eformed nuclei”, AIP Conf. Proc. 1165, 173–176(2009).
Yoshida K.: “Skyrme-QRPA calculations for low-lying excitation modes in deformed neutron-rich nuclei”, Eur.
Phys. J. A 42, No. 3, pp. 583–590 (2009).
Inakura T., Nakatsukasa T., and Yabana K.: “Systematic study of electric dipole excitations with fully selfconsisten Skyrme HF plus RPA from light to mediummass deformed nuclei”, Eur. Phys. J. A 42, 591–594(2009).
Middleton D., Annard J. R., Barbieri C., Giusti C.,
Grabmayr P., Hehl T., MacGregor I. J., Martin I.,
MacGeorge J. C., Moschini F., Pacati F. D., SchwambM., and Watts D.: “Knockout of proton-neutron pairs
from 16O with electromagnetic probes”, Eur. Phys. J.
A 43, 137–143 (2009).
Nakatsukasa T., Inakura T., and Yabana K.: “TDDFT
approach to photoabsorption in even-even nuclei”, Int.
J. Mod. Phys. A 24, 2159–2167 (2009).
Inakura T., Nakatsukasa T., and Yabana K.: “Response
functions in the continuum of deformed nuclei studied with the ime-dependent density-functional calculations”, Int. J. Mod. Phys. E 18, No. 10, pp. 2088–2092(2009).
De Rydt M., Neyens G., Asahi K., Balabanski D. L.,
Daugas J., Depuydt M., Gaudefroy L., Grevy S.,
Hasama Y., Ichikawa Y., Morel P., Nagatomo T.,
Ohtsuka T., Perrot L., Shimada K., Stoedel C., ThomasJ., Ueno H., Utsuno Y., Wannes V., Vermeulen N.,
Vingerhoets P., and Yoshimi A.: “Precision measurement of the electric quadrupole moment of 31 Al anddetermination of the eﬀective proton charge in the sdshell”, Phys. Lett. B 678, 344–349 (2009).
Long W., Nakatsukasa T., Sagawa H., Meng J., Nakada
H., and Zhang Y.: “Non-local mean ﬁeld eﬀect on nuclei
near Z = 64 sub-shell”, Phys. Lett. B 680, 428–431(2009).
Watanabe G., Dalfovo F., Piazza F., Pitaevskii L. P.,
and Stringari S.: “Critical velocity of superﬂuid ﬂow

through single-barrier and periodic potentials”, Phys.
Rev. A 80, No. 5, pp. 053602-1–053602-9 (2009).
Yoshida K.: “Core polarization for the electric quadrupole
moment of neutron rich aluminum isotopes”, Phys. Rev.
C 79, No. 5, pp. 054303-1–054303-6 (2009).
Enyo Y., Hinohara N., Suhara T., and Schuck P.: “Dineutron correlations in quasi-two-dimensional systems in a
simpliﬁed model, and possible relation to neutron-richnuclei”, Phys. Rev. C 79, No. 5, pp. 054305-1–05430514 (2009).
Takeuchi S., Aoi N., Motobayashi T., Ota S., TakeshitaE., Suzuki H., Baba H., Fukui T., Hashimoto Y., Ieki
K., Imai N., Iwasaki H., Kanno S., Kondo Y., Kubo T.,
Kurita K., Minemura T., Nakamura T., Okumura T.,
Onishi T., Sakurai H., Shimoura S., Sugou R., SuzukiD., Suzuki M., Takashina M., Tamaki M., Tanaka K.,
Togano Y., and Yamada K.: “Low-Iying States in 32Mg
studied by proton inelastic scattering”, Phys. Rev. C
79, No. 5, pp. 054319-1–054319-11 (2009).
Barbieri C. and Hiorth-Jensen M.: “Quasiparticle andquasihole states of nuclei around 56Ni”, Phys. Rev. C
79, 064313-1–064313-12 (2009).
Hinohara
N.,
Nakatsukasa
T.,MatsuoM.,
and Matuyanagi K.:“Microscopic description ofoblate-prolate shape mixing in proton-rich Se isotopes”,
Phys. Rev. C 80, No. 1, pp. 014305-1–014305-11(2009).
Taniguchi Y., Enyo Y., and Kimura M.: “Cluster structures and superdeformation in 28 Si”, Phys. Rev. C 80,
No. 4, pp. 044316-1–044316-9 (2009).
Yoshida K.: “Pygmy dipole mode in deformed neutronrich Mg isotopes close to the drip line”, Phys. Rev. C
80, No. 4, pp. 044324-1–044324-8 (2009).
Inakura T., Nakatsukasa T., and Yabana K.: “Selfconsistent calculation of nuclear photoabsorption crosssections: Finite amplitude method with Skyrme functionals in the three-dimensional real space”, Phys. Rev.
C 80, 044301-1–044301-11 (2009).
Yamagami M., Shimizu Y., and Nakatsukasa T.: “Optimal
pair density functional for description of nuclei ith large
neutron excess”, Phys. Rev. C 80, 064301-1–064301-10(2009).
Want X., Janssens R., Carpenter M. P., Zhu S.,
Wiedenhover I., Garg U., Frauendorf S., NakatsukasaT., Ahmad I., Bernstein A., Diﬀenderfer E., Freeman S.
J., Greene J. P., Khoo T., Kondev F. G., Larabee A.,
Lauritsen T., Lister C. J., Meredith B., Seweryniak D.,
Teal C., and Wilson P.: “Structure of 240 Pu: Evidence
for octupole phonon condensation?”, Phys. Rev. Lett.
102, 122501-1–122501-4 (2009).
Watanabe G., Sonoda H., Maruyama T., Katsuhiko S.,
Yasuoka K., and Ebisuzaki T.: “Formation of nuclear“pasta” in supernovae”, Phys. Rev. Lett. 103, No. 12,
pp. 121101-1–121101-4 (2009).
Barbieri C.: “Role of Long-Range Correlations in the- 412 -

1

Quenching of Spectroscopic Factors”, Phys. Rev. Lett.
103, 202502-1–202502-4 (2009).
Ogasawara H., Yoshida K., Yamagami M., Mizutori S.,
and Matuyanagi K.: “Rotational Frequency Dependence of Octupole Vibrations on Superdeformed Statesin 40 Ca”, Prog. Theor. Phys. 121, No. 2, pp. 357–374(2009).
Watanabe G.: “Eﬃcient creation of maximally entangledstates by modulation of tunneling rates”, Phys. Rev. A
81, No. 2, pp. 021604-1–021604-4 (2010).
Sato K., Hinohara N., Nakatsukasa T., Matsuo M.,
and Matuyanagi K.: “A Model Analysis of Triaxial Deformation Dynamics in Oblate-Prolate Shape Coexistence Phenomena”, Prog. Theor. Phys. 123, No. 1,
pp. 129–155 (2010).
(Review)
Yoshida K.: “Low-lying excitation modes in deformed
neutron-rich nuclei”, Int. J. Mod. Phys. E 17, No.
Supplement 1, pp. 272–285 (2008).
Barbieri C. and Dickhoﬀ W. H.: “Spectroscopic Factors in
16O and Nucleon Asymmetry”, Int. J. Mod. Phys. A
24, No. 11, pp. 2060–2068 (2009).
: “”,
53, 132–141 (2009).
(Others)
Hinohara
N.,
Nakatsukasa
T.,MatsuoM.,
and Matuyanagi K.: “Collective path and inertial
mass of large-amplitude collective dynamics: Application to shape coexistence”, AIP Conf. Proc. 1175,
49–56 (2009).
Barbieri C., Charity R. J., Dickhoﬀ W. H., and Sobotka L.
G.: “Toward a Global Dispersive Optical Model for the
Driplines”, Nucl. Phys. A 834, No. 1/4, pp. 788c–791c(2010).
[Book • Proceedings
Proc.](Review)
Barbieri C.: “Toward an Ab-initio Description of Quasiparticle Properties”, Proceedings of the 12th International Conference on Nuclear Reaction Mechanisms,
Vsrenna, Italy, 2009–6, CERN-Proceedings-2010-001,
CERN, pp. 137–144 (2010).
Enyo Y., Hinohara N., Suhara T., and Schuck P.: “Dineutron correlations in nuclear surface”, Proceedings ofthe 12th International Conference on Nuclear Reaction
Mechanisms, Varenna, Italy, 2009–6, CERN, Geneva,
pp. 291–298 (2010).

Oral Presentations
Oral Presentations((International) Conference etc.)
Yoshida K.: “Skyrme QRPA calculations for collectivemodes of excitation in deformed neutron-rich nuclei”,
3rd LACM-EFES-JUSTIPEN Workshop, Oak Ridge,
USA, Feb. (2009).
Yoshida K.: “Low-lying monopole and quadrupole modes

in deformed neutron-rich nuclei”, LIA-EFES Workshop ”Low-energy collective excitations in exotic nuclei”,
Caen, France, Mar. (2009).
Avogadro P. and Nakatsukasa T.: “Does the ﬁnite amplitude method allow to obtain easily the QRPA matrix?”, Arctic FIDIPRO-EFES Workshop, (Universityof Jyvaskyla), Saariselka, Finland, Apr. (2009).
Nakatsukasa T.: “Finite amplitude method and systematic studies of photoresponse in deformed nuclei”, Arctic
FIDIPRO-EFES Workshop, (University of Jyvaskyla),
Saariselka, Finland, Apr. (2009).
Hinohara
N.,
Nakatsukasa
T.,MatsuoM.,
and Matuyanagi K.: “Collective path and inertial
mass of large-amplitude collective dynamics: application to shape coexistence”, 4th International Workshop
on Nuclear Fission and Fission-Product Spectroscopy(FISSION
2009), (CEA), Saint-Paul-lez-Durance,
France, May (2009).
Watanabe G., Orso G., Dalfovo F., Pitaevskii L. P.,
and Stringari S.: “Properties of superﬂuid unitary Fermi
gases in an optical lattice”, Conference on Research
Frontiers in Ultra-Cold Atoms, (ICTP), Trieste, Italy,
May (2009).
Nakatsukasa T.: “Finite amplitude method and systematicstudies of photoresponse in deformed nuclei”, International Conference on Nuclear Structure and Dynamics(NSD09), (University of Zagreb), Dubrovnik, Croatia,
May (2009).
Yoshida K.: “Monopole modes of excitation in deformed
neutron-rich Mg isotopes”, International Conference on
Nuclear Structure and Dynamics (NSD09), (Universityof Zagreb), Dubrovnik, Croatia, May (2009).
Yoshida K.: “Collective modes of excitation in deformed
neutron-rich nuclei”, Workshop on Importance of continuum coupling for nuclei close to the drip-lines, (CEA
Saclay), Saclay, France, May (2009).
Hinohara N.: “Oblate-prolate shape mixing in proton-rich
Se isotopes as large-amplitude collective motion”, Workshop on Importance of continuum coupling for nuclei
close to the drip-lines, (CEA/SPhN), Saclay, France,
May (2009).
Taniguchi Y., Enyo Y., and Kimura M.: “Clustering andshape coexistence in 28 Si”, YITP International Workshop on Development of nuclear structure models fromthe viewpoint of nuclear force, (Yukawa Institute for
Theoretical Physics, Kyoto University), Kyoto, May(2009).
Barbieri C.: “Green’s Functions Calculations of Quasiparticle States”, YITP International Workshop on Development of nuclear structure models from the viewpoint of nuclear force, (Yukawa Institute for Theoretical
Physics), Kyoto, May (2009).
Nakatsukasa T.: “Recent activities in RIKEN RI Beam
Factory: Experiments and theories”, 12th International
Conference on Nuclear Reaction Mechanisms, (Univer-- 413 -

2

sity of Milano), Varenna, Italy, June (2009).
Barbieri C.: “Toward an Ab-initio Description of Quasiparticle Properties”, 12th International Conference on
Nuclear Reaction Mechanisms, Varenna, Italy, June(2009).
Yoshida K.:“Giant monopole resonance and soft
monopole mode in neutron-rich Mg isotopes”, 3rd International Conference on Collective Motion in Nuclei under Extreme Conditions (COMEX3), ( National Superconducting Cyclotron Laboratory (NSCL) at Michigan
State University), Mackinac Island, USA, June (2009).
Nakatsukasa T.: “Finite amplitude method and canonicalbasis TDHFB”, Annual UNEDF Collaboration Meetings, (University of Washington), Pack Forest, USA,
June (2009).
Watanabe G.: “Eﬃcient scheme for creating NOON state
in a double-well potential”, Cold Atoms and Molecules:
Collisions, Field-eﬀects, and Applications, (Kyoto University), Kyoto, June (2009).
Barbieri C.: “Toward an ab-initio description of singleparticle properties”, ECT International Workshop on
Confrontation and Convergence in Nuclear Theory,
Trento, Italy, July (2009).
Barbieri C.: “Applicazioni delle funzioni di green agli statidi quasiparticella in atomi e nuclei”, Seminar at the University of Pavia, (University of Pavia), Pavia, Italy, July(2009).
Barbieri C.: “Applications of many-body theory to derive accurate global optical potentials and predictions
at the driplines”, 10th International Conference on
Nucleus-Nucleus collisions (NN2009), Beijing, China,
Aug. (2009).
Watanabe G.: “Eﬃcient scheme for creating NOON
state in a double-well potential”, Telluride Workshop
on Quantum Chemistry and Quantum Computational
Physics in the Theory of Ultra-cold Gasses, Telluride,
USA, Aug. (2009).
Taniguchi Y., Enyo Y., and Kimura M.: “α clustering andsuperdeformation of 28 Si”, 19th International IUPAP
Conference on Few-Body Problems in Physics, Bonn,
Germany, Aug.–Sept. (2009).
Hinohara N.: “Large-amplitude collective dynamics inproton-rich Se isotopes”, 8th CNS-EFES International
Summer School (CNS-EFES09), Wako, Aug.–Sept.
(2009).
Watanabe G.: “Nuclear “pasta”: its formation and consequences”, Conference on Neutron stars: The crust andbeyond, (NORDITA), Stockholm, Sweden, Sept. (2009).
Watanabe G.: “Eﬃcient scheme for creating maximallyentangled state in a double-well potential”, International Conference on Quantum Information Processing and Communication (QIPC 2009), (QUROPE andthe Sapienza Universita di Roma), Rome, Italy, Sept.
(2009).
Avogadro P. and Nakatsukasa T.: “A method to compute

the QRPA”, 3rd Joint Meeting of the APS Divisionof Nuclear Physics and the Physical Society of Japan(HAW 09), (APS, JPS), Waikoloa, USA, Oct. (2009).
Kohama A., Iida K., and Oyamatsu K.: “Constructing formula for total reaction cross sections without adjustableenergy-dependent parameters”, 3rd Joint Meeting of the
Nuclear Physics Divisions of the APS and JPS (Hawaii2009), Hawaii, USA, Oct. (2009).
Barbieri C.: “Large-Scale Calculations of Single-Particle
Properties”, 3rd Joint Meeting of the Nuclear Physics
Divisions of the APS and JPS (Hawaii 2009), Hawaii,
USA, Oct. (2009).
Nakatsukasa T., Hinohara N., Sato K., Matsuo M.,
and Matuyanagi K.: “Microscopic analysis of large amplitude collective dynamics in triaxial nuclear shapes”,
3rd Joint Meeting of the Nuclear Physics Divisions of the
APS and JPS (Hawaii 2009), Hawaii, USA, Oct. (2009).
Nakatsukasa T.: “Photnuclear reactions studied with thetime-dependent density-functional theory”, 3rd Joint
Meeting of the Nuclear Physics Divisions of the APS
and JPS (Hawaii 2009), Hawaii, USA, Oct. (2009).
Hinohara N., Sato K., Nakatsukasa T., Matsuo M.,
and Matuyanagi K.: “Microscopic derivation of ﬁvedimensional collective Hamiltonian of large-amplitude
quadrupole motion: application to shape coexistence inproton-rich Se isotopes”, 7th Japan-China Joint Nuclear
Physics Symposium, (Univ. of Tsukuba), Tsukuba,
Nov. (2009).
Hinohara N., Sato K., Nakatsukasa T., Matsuo M.,
and Matuyanagi K.: “Large-amplitude quadrupole collective dynamics in Se and Kr isotopes”, Hadron and
Nuclear Physics (HNP09), (RCNP, Osaka Univ.), Suita,
Nov. (2009).
Watanabe G.: “Study of matter in ultradense and ultradilute environments: towards bridging astrophysics andcold atom physics”, Symposium on Fields of Special Interests in Theoretical Physics, (Asia Paciﬁc Center for
Theoretical Physics), Pohang, Korea, Nov. (2009).
Hinohara N., Sato K., Nakatsukasa T., Matsuo M.,
and Matuyanagi K.: “Large-amplitude quadrupole collective dynamics of shape coexistence phenomena inproton-rich Se and Kr isotopes”, Tours Symposium on
Nuclear Physics and Astrophysics VII (TOURS 2009),(Konan Univ.), Kobe, Nov. (2009).
Hinohara N.: “Five-dimensional collective Hamiltonian
with Thouless-Valatin inertial functions”, JUSTIPENEFES Workshop on Unstable Nuclei, Wako, Dec.
(2009).
Barbieri C.: “Ground states and single particle energies
from Green’s function theory”, JUSTIPEN-EFES Workshop on Unstable Nuclei, Wako, Dec. (2009).
Taniguchi Y., Kimura M., Enyo Y., Ikeda K., Horiuchi H.,
and Ideguchi E.: “Triaxial superdeformation in 40 Ar”,
JUSTIPEN-EFES Workshop on Unstable Nuclei, Wako,
Dec. (2009).

- 414 -

3

Watanabe G.: “Formation of nuclear “pasta” in supernovae”, RIKEN-TRIUMF Nuclear Theory Meeting, (TRIUMF and RIKEN), Vancouver, Canada, Dec.
(2009).
Nakatsukasa T.: “Global ﬁtting of the pairing functional”,
RIKEN-TRIUMF Nuclear Theory Meeting, Vancouver,
Canada, Dec. (2009).
Watanabe G.: “Formation of nuclear pasta in supernovae”,
Mini Symposium on Nuclear Astrophysics in “New Frontiers in QCD 2010”, (Yukawa Institute for Theoretical
Physics), Kyoto, Jan. (2010).
Hinohara N.: “Beyond mean-ﬁeld description of low-lying
states of nuclei”, ICHOR-EFES International Symposium on New Facet of Spin-Isospin Responses (SIR2010),(University of Tokyo), Tokyo, Feb. (2010).
Barbieri C.: “Pygmy dipole response of proton-rich argon nuclei in random-phase approximation and no-coreshell model”, ICHOR-EFES International Symposium
on New Facet of Spin-Isospin Responses (SIR2010),(Tokyo University/CNS), Tokyo, Feb. (2010).
Yoshida K.: “Pygmy mode in deformed neutron-rich nuclei”, ICHOR-EFES International Symposium on New
Facet of Spin-Isospin Responses (SIR2010), Tokyo, Feb.
(2010).
Barbieri C.: “Ground and Single-Particle States fromGreen’s Function Theory”, International Symposium on
Forefronts of Researches in Exotic Nuclear Structures(Niigata2010), (Niigata University), Tokamachi, Niigata
Pref., Mar. (2010).
Sato K., Hinohara N., Nakatsukasa T., Matsuo M.,
and Matuyanagi K.: “Microscopic analysis of shapemixing in low-lying states of proton-rich Kr isotopes”,
International Symposium on Forefronts of Researches in
Exotic Nuclear Structures (Niigata2010), (Niigata University), Tokamachi, Niigata Pref., Mar. (2010).
Hinohara N., Sato K., Nakatsukasa T., Matsuo M.,
and Matuyanagi K.: “Microscopic approach to adiabatic large-amplitude quadrupole collective dynamics in
Se isotopes”, International Symposium on Forefronts of
Researches in Exotic Nuclear Structures (Niigata2010),(Niigata Univ.), Tokamachi, Niigata Pref., Mar. (2010).
Sato K., Hinohara N., Nakatsukasa T., Matsuo M.,
and Matuyanagi K.: “Phenomenological analysis of
the oblate-prolate symmetry breaking in triaxial deformation dynamics”, International Symposium on Forefronts of Researches in Exotic Nuclear Structures (Niigata2010), (Niigata University), Tokamachi, Niigata
Pref., Mar. (2010).
Taniguchi Y.: “Triaxial superdeformation in 40 Ar”, International Symposium on Forefronts of Researches in
Exotic Nuclear Structures (Niigata2010), (Niigata University), Toka-machi, Niigata Pref., Mar. (2010).
Avogadro P. and Nakatsukasa T.: “Finite amplitude
method for the QRPA”, International Symposium on
Forefronts of Researches in Exotic Nuclear Structures(Niigata2010), (Niigata University), Tokamachi, Niigata
Pref., Mar.–Mar. (2010).
((Domestic)Conference)
Barbieri C.: “Green’s Functions Calculations of Spectroscopic Factors”,
64,,3(2009).
: “Low-frequency vibrational modes in neutronrich Mg isotopes close to the drip line”,
64,, 3 (2009).
,
,
: “
”,
64
,
, 3 (2009).
,
,
,
,
: “
40
Ca
RPA
”,
64
,
, 3 (2009).
: “”, NumazuWorkshop 2009,(),,3
(2009).
: “”, RIBF,, 3 (2009).
: “”, RIBF,, 3 (2009).
: “
”,
5
,(
),
, 5 (2009).
: “Purpose of this WS and the overview : how
to deduce charge densities”, RIBF
”Electron Scattering data needed for the charge-density
determination of unstable nuclei”,, 5 (2009).
: “Systematic analyses of total reaction cross ections using the black-sphere picture of nuclei”, RIBF
”One goal, diﬀerent approaches - how to, 5 (2009).
predict total reaction cross sections”,
: “
”,
2
,(
),
, 7 (2009).
Barbieri C.: “Toward an “ab-initio” Description of SingleParticle Properties”,, (Chiba university), Chiba university, 7(2009).
: “Collectivity in nuclei at around and beyond theisland of inversion”,,, 7 (2009).
: “Eﬃcient scheme for creating NOON state ina double-well potential”, Workshop on Quantum Foundations for Young Researchers: From Mathematical
Physics to Experimental Physics, (Student Chapter),, 7 (2009).
: “”, KEK,, 8 (2009).

- 415 -

4

,,
TDHF+“BCS”

,

,

),
: “

: “Skyrme”, KEK,(,8(2009).
”, KEK, (KEK),,8(2009).
: “Pygmy mode in deformed neutron-rich Mg isotopes close to the drip line”, RCNP
E1,M1
,(
),
, 8 (2009).
: “”,,, 9 (2009).
: “Eﬃcient scheme for creating NOON state
in a double-well potential: assisted higher-order co, (tunneling”,),, 9 (2009).
: “
”,
,(
),
, 11
(2009).
: “A tool to solve the QRPA probAvogadro P.,
lem fully self-consistently and with no symmetry restriction”, JUSTIPEN Workshop,, 12 (2009).
: “
”,
S2010
,(
),
, 1 (2010).
Barbieri C.: “Toward an accurate understanding of opticalmodels and single-particle states in exotic nuclei”, RIBF
, Wako, 1(2010).
: “
NOON
”,
65
,(
),
, 3 (2010).
,: “5Hamiltonian
Kr
”,
65
,
, 3 (2010).
,
,
,
,
: “
Hamiltonian
Se
”,
65
,
, 3 (2010).
,
,
,
,
: “
Skyrme-TDHF+“BCS””,
65,, 3 (2010).
: “40 Ar”,
65,
, 3 (2010).

- 416 -

5

StrangenessNuclear Physics Laboratory
RNC
Publications
Publications[Journal](Original Papers) *Subject to Peer Review
Nemura H.: “A New Three-Baryon-Force in ΛΛ Hypernuclei”, AIP Conf. Proc. 1011, 129–134 (2008).
Hatsuda T., Aoki S., Ishii N., and Nemura H.: “From Lattice QCD to Nuclear Force”, Mod. Phys. Lett. A 23,
2265–2272 (2008).
Nemura H., Ishii N., Aoki S., and Hatsuda T.: “Lattice
QCD Simulation of Hyperon-Nucleon Potential”, Mod.
Phys. Lett. A 23, 2285–2288 (2008).
Nemura H.: “ΛΛ-N Ξ-ΛΣ-ΣΣ Coupled Channel Calculations of Doubly Strange Hypernuclei”, Nucl. Phys. A
805, 191–193 (2008).
Aoki S., Balog J., Hatsuda T., Ishii N., Murano K.,
Nemura H., and Weisz P.: “Energy Dependence of
Nucleon-Nucleon Potentials”, Proceedings of Science
LATTICE 2008, No. 152, pp. 1–7 (2008).
Nemura H., Ishii N., Aoki S., and Hatsuda T.: “Lambdanucleon force from lattice QCD”, Proceedings of Science
LATTICE 2008, No. 156, pp. 1–7 (2008).
Umeya A., Kaneko G., and Muto K.: “Shell-model calculation of E2 eﬀective charges: Application to carbon
isotopes”, Nucl. Phys. A 829, 13–30 (2009).
Nemura H., Ishii N., Aoki S., and Hatsuda T.: “Hyperonnucleon force from lattice QCD”, Phys. Lett. B 673,
136–141 (2009).
Hiyama E., Yamamoto Y., Motoba T., and Kamimura M.:“Structure of A=7 Iso-Triplet Λ Hypernuclei Studied
with the Four-Body Cluster Model”, Phys. Rev. C 80,
054321-1–054321-12 (2009).
(Review)
Hiyama E. and Yamada T.: “Structure of Light Hypernuclei”, Prog. Part. Nucl. Phys. 63, No. 2, pp. 339–395(2009).

Oral Presentations
Oral Presentations((International) Conference etc.)
Nemura H., Ishii N., Aoki S., and Hatsuda T.: “Lambdanucleon force from lattice QCD”, Lattice 2008, 26th International Symposium on Lattice Field Theory, (College of Williams and Mary), Virginia, USA, July (2008).
Nemura H., Ishii N., Aoki S., and Hatsuda T.: “Hyperonnucleon force calculated from lattice QCD”, KGU Yokohama Autumn School of Nuclear Physics, (KGU), Yokohama, Oct. (2008).
Nemura H., Ishii N., Aoki S., and Hatsuda T.: “Studyof hyperon-nucleon potential from lattice QCD”, Sendai
International Symposium on Strangeness in Nuclear andHadronic Systems (SENDAI08), (Tohoku University),
Sendai, Dec. (2008).
Hiyama E.: “Structure of Three- and Four-Body Light
Hypernuclei”, International Summer School on Sub-atomic Physics / 5th course: Some New Facets in Nuclear Physics, (Peking University), Beijing, China, Aug.
(2009).
Ikeda Y., Aoki S., Hatsuda T., Ishii N., Nemura H., InoueT., Doi T., Sasaki K., and Murano K.: “Kaon-nucleon
potential from lattice QCD”, 19th International IUPAP
Conference on Few-Body Problems in Physics, (University of Bonn), Bonn, Germany, Aug.–Sept. (2009).
Hiyama E.: “Recent Progress in Hypernuclear Physics”,
19th International IUPAP Conference on Few-Body
Problems in Physics, (University of Bonn), Bonn, Germany, Aug.–Sept. (2009).
Umeya A. and Harada T.: “Sigma-admixture in neutronrich lithium Lambda hypernuclei in a microscopic shellmodel calculation”, 19th International IUPAP Conference on Few-Body Problems in Physics, (University ofBonn), Bonn, Germany, Aug.–Sept. (2009).
Hiyama E.: “Few Body Systems with S=-1,-2”, 10th International Conference on Hypernuclear and Strange Particle Physics (Hyp-X), (Kyoto university, the Global COE
Program ), Tokai-mura, Ibaraki Pref., Sept. (2009).
Ikeda Y., Sato T., and Kamano H.: “On the resonanceenergy of the KbarNN-piYN system”, 10th International Conference on Hypernuclear and Strange Particle Physics (Hyp-X), Tokai-mura, Ibaraki Pref., Sept.
(2009).
Umeya A. and Harada T.: “Shell-model study on Sigmamixing in neutron-rich lithium Lambda hypernuclei”,
10th International Conference on Hypernuclear andStrange Particle Physics (Hyp-X), (Kyoto university),
Tokai-mura, Ibaraki Pref., Sept. (2009).
Rijken T. A.: “Status of Our Understanding on the YN
Interaction”, 10th International Conference on Hypernuclear and Strange Particle Physics (Hyp-X), (Kyoto university, the Global COE Program ), Tokai-mura, Ibaraki
Pref., Sept. (2009).
Hiyama E., Kamimura M., and Yamamoto Y.: “FiveBody Structure of Double Λ Hypernuclei”, 3rd Joint
Meeting of the APS Division of Nuclear Physics and the
Physical Society of Japan (HAW 09), Hawaii, USA, Oct.
(2009).
Umeya A., Motoba T., and Harada T.: “Shell model studyof typical sd-shell hypernuclei”, 3rd Joint Meeting of the
Nuclear Physics Divisions of the APS and JPS (Hawaii2009), (APS Division of Nuclear Physics, The PhysicalSociety of Japan), Hawaii, USA, Oct. (2009).
Ikeda Y., Aoki S., Doi T., Hatsuda T., Inoue T., Ishii N.,
Nemura H., Sasaki K., and Murano K.: “NK potential infull QCD lattice simulation”, US-Japan Joint Workshop
on Mesnon Production Reaction at Jeﬀerson Lab and
J-PARC, Hawaii, USA, Oct. (2009).
Hiyama E.: “Light Ξ Hypernuclei in Four-Body Cluster Models”, Hadron and Nuclear Physics (HNP09),(RCNP), Osaka, Nov. (2009).
Umeya A., Motoba T., and Harada T.: “Shell-model cal-

- 417 -

1

culations for typical sd-shell hypernuclei”, Hadron and
Nuclear Physics (HNP09), (Osaka University, RCNP),
Osaka, Nov. (2009).
Rijken T. A.: “Strange and Non-Strange Baryon-Baryon
Interactions Recent Nijmegen Extended-Soft-Core Models”, Hadron and Nuclear Physics (HNP09), (RCNP),
Osaka, Nov. (2009).
Hiyama E.: “Theory of Light Hypernuclear Structure
Cluster Model Approach”, 2nd JSPS Core-to-core Seminar on Strangeness Nuclear Physics by Electron Beams,
Rome, Italy, Dec. (2009).
Ikeda Y., Aoki S., Doi T., Hatsuda T., Inoue T., Ishii N.,
Murano K., Nemura H., and Sasaki K.: “K-N potential
and Theta+ in lattice QCD”, New Frontiers in QCD
2010, (YITP), Kyoto, Jan.–Mar. (2010).
((Domestic)Conference)
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
, Beer G.
A.,, Choi S.,,, Buehler P., Hirtl
A., Cargnelli M., Kienle P., Marton J., Widmann E.,
Zmeskal J., Curceanu C. O., Guaraldo C., Iliescu M.,
Pietreanu D., Sirghi D., Sirghi F., Faso D., Busso L.,
Morra O.: “K
3
”,
2007
,
,
(2007).
3
,
,
,
: “
QCD
”,
- ,(
),
, 8 (2008).
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
, Beer G. A.,, Choi,, Buehler P., Cargnelli M., Hirtl A.,S.,
Kienle P., Marton J., Widmann E., Zmeskal J.,,
Curceanu C. O., Guaraldo C., Iliescu M., Pietreanu D.,
Sirghi D., Sirghi F., Faso D., Morra O., Busso L.: “K
3
III”,
2008
,
, 9 (2008).
: “
QCD
J-PARC”, J-PARC,, 9 (2008).
,
,
,
: “
QCD
”,

,

,

,

: “

QCD

(2009).
: “
64

QCD

: “

QCD

”,

,
,

,2

,

ΛN

,

”,
, 3 (2009).
,
,
”,

),
,

,(

A02
,
: “
),

,4

, 3 (2009).
”, RCNP,((2009).

: “”,,(2009).
,: “”, KEK
,(

),

,6

,8

(2009).
: “”,,(, 8 (2009).
: “Few-Body Structure of S=-2 Systems”,,
Workshop on Flavor Nuclear Physics in HIDA,
11 (2009).
,
: “
”,
),

,(

RCNP),, 12(2009).
: “

I
,

: “
,

,1
: “

”,
,(

, 12
4

3
”,
22
(2010).

”,(2009).

7),,3(2010).

2008,, 10 (2008).
,,,: “Hyperon Potentials from Lattice QCD”, Aizu meeting 2009 on Spin
Excitations and Exotic Degree of Freedom in Nuclei and,2(2009).
Nuclear Matter,- 418 -

2

Radiation Laboratory
RNC
Publications
Publications[Journal](Original Papers) *Subject to Peer Review
Hatsuda T., Aoki S., Ishii N., and Nemura H.: “From Lattice QCD to Nuclear Force”, Mod. Phys. Lett. A 23,
2265–2272 (2008).
Nemura H., Ishii N., Aoki S., and Hatsuda T.: “Lattice
QCD Simulation of Hyperon-Nucleon Potential”, Mod.
Phys. Lett. A 23, 2285–2288 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bazilevsky A. V.,
Bunce G. M., Deshpande A., Enyo H., Fields D. E.,
Fox B., Fujiwara K., Fukao Y., Goto Y., Gross P. M.,
Hasuko K., Heuser J. M., Horaguchi T., Ichihara T.,
Imai K., Inoue Y., Ishihara M., Jinnouchi O., KamiharaN., Kaneta M., Kanoh H., Kawall D., Kiyomichi A.,
Kobayashi H., Kurita K., Mao Y., Murata J., Nakagawa
I., Nakano K., Onishi H., Okada H., Okada K., Rykov V.
L., Saito N., Sato H., Shibata T., Shoji K., Tabaru T.,
Taketani A., Tanida K., Togawa M., Tojo J., Torii H.,
Wagner M. M., Watanabe Y., Xie W., and Yokkaichi
S.: “Cold Nuclear Matter Eﬀects on J/ψ Production as Constrained by Deuteron-Gold Measurements at√
sNN = 200 GeV”, Phys. Rev. C 77, 024912-1–02491215 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K., Fukao
Y., Goto Y., Gross P. M., Hachiya T., Hasuko K., Heuser
J. M., Horaguchi T., Ichihara T., Imai K., Inoue Y.,
Ishihara M., Jinnouchi O., Kajihara F., Kamihara N.,
Kaneta M., Kanoh H., Kawall D., Kiyomichi A., Kurita
K., Mao Y., Murata J., Nakagawa I., Nakano K., Onishi
H., Okada H., Okada K., Rykov V. L., Saito N., Sato H.,
Shibata T., Shoji K., Tabaru T., Taketani A., Tanida K.,
Togawa M., Tojo J., Torii H., Tsuchimoto Y., Wagner
M. M., Watanabe Y., Xie W., and Yokkaichi S.: “Quantitative Constraints on the Transport Properties of Hot
Partonic Matter from Semi-Inclusive Single High Transverse Momentum Pion Suppression in Au+Au Collisions√
at sNN = 200 GeV”, Phys. Rev. C 77, 064907-1–
064907-12 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K., Fukao
Y., Goto Y., Gross P. M., Hachiya T., Hasuko K., Heuser
J. M., Horaguchi T., Ichihara T., Imai K., Inoue Y.,
Ishihara M., Jinnouchi O., Kajihara F., Kamihara N.,
Kaneta M., Kanoh H., Kawall D., Kiyomichi A., Kurita
K., Mao Y., Murata J., Nakagawa I., Nakano K., Onishi
H., Okada H., Okada K., Rykov V. L., Saito N., Sato H.,
Shibata T., Shoji K., Tabaru T., Taketani A., Tanida K.,
Togawa M., Tojo J., Torii H., Tsuchimoto Y., Wagner
M. M., Watanabe Y., Xie W., and Yokkaichi S.: “Dihadron azimuthal correlations in Au+Au collisions at√
sNN = 200 GeV”, Phys. Rev. C 78, 014901-1–014901-

42 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bazilevsky A. V.,
Bunce G. M., Deshpande A., Enyo H., Fields D. E.,
Fox B., Fujiwara K., Fukao Y., Goto Y., Gross P. M.,
Hachiya T., Hasuko K., Heuser J. M., Horaguchi T.,
Ichihara T., Imai K., Inoue Y., Ishihara M., Jinnouchi
O., Kajihara F., Kamihara N., Kaneta M., Kanoh H.,
Kawall D., Kiyomichi A., Kobayashi H., Kurita K., Mao
Y., Murata J., Nakagawa I., Nakano K., Onishi H.,
Okada H., Okada K., Rykov V. L., Saito N., Sato H.,
Shibata T., Shoji K., Tabaru T., Taketani A., Tanida
K., Togawa M., Tojo J., Torii H., Tsuchimoto Y.,
Wagner M. M., Watanabe Y., Xie W., and Yokkaichi
S.: “Charged hadron multiplicity ﬂuctuations in Au+Au√
and Cu+Cu collisions from sNN = 22.5 to 200 GeV”,
Phys. Rev. C 78, 044902-1–044902-15 (2008).
Afanasiev S., Akiba Y., Aoki K., Bunce G. M., DeshpandeA., Enyo H., Fields D. E., Fukao Y., Goto Y., Gross P.
M., Hachiya T., Hasuko K., Heuser J. M., Horaguchi
T., Ichihara T., Imai K., Ishihara M., Jinnouchi O.,
Kajihara F., Kamihara N., Kaneta M., Kiyomichi A.,
Kurita K., Murata J., Onishi H., Okada H., Okada K.,
Rykov V. L., Saito N., Sato H., Shibata T., Shoji K.,
Tabaru T., Taketani A., Tanida K., Togawa M., TojoJ., Torii H., Tsuchimoto Y., Wagner M. M., WatanabeY., Xie W., and Yokkaichi S.: “Source breakup dynam√
ics in Au+Au Collisions at sNN =200 GeV via threedimensional two-pion source imaging”, Phys. Rev. Lett.
100, 232301-1–232301-6 (2008).
Afanasiev S., Akiba Y., Aoki K., Bunce G. M., DeshpandeA., Enyo H., Fields D. E., Fukao Y., Goto Y., Gross P.
M., Hachiya T., Hasuko K., Heuser J. M., Horaguchi
T., Ichihara T., Imai K., Ishihara M., Jinnouchi O.,
Kajihara F., Kamihara N., Kaneta M., Kiyomichi A.,
Kurita K., Murata J., Onishi H., Okada H., Okada K.,
Rykov V. L., Saito N., Sato H., Shibata T., Shoji K.,
Tabaru T., Taketani A., Tanida K., Togawa M., Tojo J.,
Torii H., Tsuchimoto Y., Wagner M. M., Watanabe Y.,
Xie W., and Yokkaichi S.: “Particle-species dependent
modiﬁcation of jet-induced correlations in Au+Au col√lisions at sNN = 200 GeV”, Phys. Rev. Lett. 101,
082301-1–082301-6 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K., Fukao
Y., Goto Y., Gross P. M., Horaguchi T., Ichihara T.,
Imai K., Inoue Y., Ishihara M., Jinnouchi O., KamiharaN., Kaneta M., Kanoh H., Kawall D., Kiyomichi A.,
Kurita K., Mao Y., Murata J., Nakagawa I., Nakano
K., Onishi H., Okada H., Okada K., Rykov V. L.,
Saito N., Shibata T., Shoji K., Tabaru T., Taketani A.,
Tanida K., Togawa M., Tojo J., Torii H., Wagner M.
M., Watanabe Y., Xie W., and Yokkaichi S.: “J/ψ Pro√
duction in sNN = 200 GeV Cu+Cu Collisions”, Phys.
Rev. Lett. 101, 122301-1–122301-6 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,- 419 -

1

Dairaku S., Deshpande A., Enyo H., Fields D. E.,
Fujiwara K., Fukao Y., Goto Y., Gross P. M., Horaguchi
T., Ichihara T., Ichimiya R., Imai K., Inoue Y., Ishihara
M., Jinnouchi O., Kametani S., Kamihara N., Kaneta
M., Kanoh H., Kawall D., Kiyomichi A., Kurita K.,
Kurosawa M., Li Z., Mao Y., Murata J., Nakagawa I.,
Nakano K., Onishi H., Okada H., Okada K., Onuki Y.,
Rykov V. L., Saito N., Sakashita K., Shibata T., Shoji
K., Tabaru T., Taketani A., Tanida K., Togawa M.,
Tojo J., Torii H., Wagner M. M., Watanabe Y., Xie W.,
and Yokkaichi S.: “Onset of π 0 suppression studied in√
Cu+Cu collisions at sNN = 22.4, 62.4, and 200 GeV”,
Phys. Rev. Lett. 101, 162301-1–162301-6 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K.,
Fukao Y., Goto Y., Gross P. M., Hachiya T., Hasuko K.,
Heuser J. M., Horaguchi T., Ichihara T., Imai K., Inoue
Y., Ishihara M., Jinnouchi O., Kajihara F., KamiharaN., Kaneta M., Kanoh H., Kawall D., Kiyomichi A.,
Kurita K., Mao Y., Murata J., Nakagawa I., Nakano K.,
Onishi H., Okada H., Okada K., Rykov V. L., Saito N.,
Sato H., Shibata T., Shoji K., Tabaru T., Taketani A.,
Tanida K., Togawa M., Tojo J., Torii H., Tsuchimoto Y.,
Wagner M. M., Watanabe Y., Xie W., and Yokkaichi S.:“Suppression pattern of neutral pions at high transverse√
momentum in Au+Au collisions at sNN = 200 GeV
and constraints on medium transport coeﬃcients”, Phys.
Rev. Lett. 101, 232301-1–232301-7 (2008).
Aoki S., Balog J., Hatsuda T., Ishii N., Murano K.,
Nemura H., and Weisz P.: “Energy Dependence of
Nucleon-Nucleon Potentials”, Proceedings of Science
LATTICE 2008, No. 152, pp. 1–7 (2008).
Nemura H., Ishii N., Aoki S., and Hatsuda T.: “Lambdanucleon force from lattice QCD”, Proceedings of Science
LATTICE 2008, No. 156, pp. 1–7 (2008).
Hata M., Akiyama T., Ikeda Y., Kawamura H., Narota
K., Ninomiya K., Ogawa N., Sato T., Seitaibashi E.,
Sekiguchi Y., Tsutsui R., Yazawa K., and Murata J.:“Recent results on short-range gravity experiment”, J.
Phys.: Con. Ser. 189, 012019-01–012019-10 (2009).
Ninomiya K., Akiyama T., Hata M., Ikeda Y., Kawamura
H., Narota K., Ogawa N., Sato T., Seitaibashi E.,
Sekiguchi Y., Tsutsui R., Yazawa K., and Murata J.:“New experimental technique for short-range gravity
measurement”, J. Phys.: Con. Ser. 189, 012026-1–
012026-7 (2009).
Akiba Y.: “Dilepton radiation measured in PHENIX probing the strongly interacting matter created at RHIC”,
Nucl. Phys. A 830, 567–570 (2009).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K., Fukao
Y., Goto Y., Gross P. M., Horaguchi T., Ichihara T.,
Imai K., Inoue Y., Ishihara M., Jinnouchi O., KamiharaN., Kaneta M., Kanoh H., Kawall D., Kiyomichi A.,
Kurita K., Mao Y., Murata J., Nakagawa I., Nakano K.,

Onishi H., Okada H., Okada K., Rykov V. L., Saito N.,
Shibata T., Shoji K., Tabaru T., Taketani A., Tanida K.,
Togawa M., Tojo J., Torii H., Wagner M. M., WatanabeY., Xie W., and Yokkaichi S.: “Dilepton mass spectra√in p+p collisions at s = 200 GeV and the contribution
from open charm”, Phys. Lett. B 670, 313–320 (2009).
Nemura H., Ishii N., Aoki S., and Hatsuda T.: “Hyperonnucleon force from lattice QCD”, Phys. Lett. B 673,
136–141 (2009).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Dairaku S., Deshpande A., Enyo H., Fields D. E.,
Fujiwara K., Fukao Y., Goto Y., Gross P. M., Horaguchi
T., Ichihara T., Ichimiya R., Imai K., Ishihara M.,
Kametani S., Kamihara N., Kawall D., Kurita K.,
Kurosawa M., Li Z., Mao Y., Murata J., Nakagawa I.,
Nakano K., Okada H., Okada K., Onuki Y., Rykov V. L.,
Saito N., Sakashita K., Shibata T., Shoji K., Taketani
A., Tanida K., Togawa M., Torii H., Watanabe Y., Xie
W., and Yokkaichi S.: “Inclusive cross section and double helicity asymmetry for π 0 production in p + p colli√
sions at s = 62.4 GeV”, Phys. Rev. D 79, 012003-1–
012003-11 (2009).
(Others)
Murata J., Akiyama T., Hata M., Hirayama Y., Ikeda
Y., Ishii T., Kameda D., Kawamura H., Mitsuoka
S., Miyatake H., Nagae D., Ninomiya K., Nitta M.,
Seitaibashi E., and Toyoda T.: “Test of time reversal
symmetry using polarized nuclei”, JAEA-Review 2009036, 62–63 (2009).
[Book • Proceedings
Proc.](Review)
Yokkaichi S.: “In-medium mass modiﬁcation of vector
mesons”, Particle and Nuclear Physics at J-PARC (Lecture Notes in Physics 781), Springer, Heidelberg, pp.
161–193 (2009).
Akiba Y.: “Heavy Ion Physics at RHIC”, Proceedings of
the 6th Japan-Italy symposium on Heavy-Ion Physics,
Tokai-mura, Ibaraki Pref., 2008–11, American Instituteof Physics, New York, pp. 157–162 (2009).

Oral Presentations
Oral Presentations((International) Conference etc.)
Takeuchi S., Shimoura S., Motobayashi T., Akiyoshi H.,
Ando Y., Aoi N., Fulop Z., Gomi T., Higurashi Y.,
Hirai M., Iwasa N., Iwasaki H., Iwata Y., Kobayashi H.,
Kurokawa M., Liu Z., Minemura T., Ozawa S., Sakurai
H., Serata M., Teranishi T., Yamada K., Yanagisawa
Y., and Ishihara M.: “Isobaric analog state of 14 Be”,
RIKEN-CNS RIBF International Workshop “Correlation and Condensation: New Features in Loosely Boundand Unbound Nuclear States”, Wako, Dec. (2005).
Nemura H., Ishii N., Aoki S., and Hatsuda T.: “Lambdanucleon force from lattice QCD”, Lattice 2008, 26th International Symposium on Lattice Field Theory, (Col-- 420 -

2

lege of Williams and Mary), Virginia, USA, July (2008).
Nemura H., Ishii N., Aoki S., and Hatsuda T.: “Hyperonnucleon force calculated from lattice QCD”, KGU Yokohama Autumn School of Nuclear Physics, (KGU), Yokohama, Oct. (2008).
Nemura H., Ishii N., Aoki S., and Hatsuda T.: “Studyof hyperon-nucleon potential from lattice QCD”, Sendai
International Symposium on Strangeness in Nuclear andHadronic Systems (SENDAI08), (Tohoku University),
Sendai, Dec. (2008).
Enyo H.: “RIKEN Activity at J-PARC”, International
Workshop on Physics and Upgrade of the J-PARC
Hadron Facility, (RCNP, Osaka University, RIKEN),
Tokai-mura, Ibaraki Pref., Sept. (2009).
Enyo H.: “Experimental Quest for Proton Spin Structure:
Past, Present and Future”, 3rd Joint Meeting of the
Nuclear Physics Divisions of the APS and JPS (Hawaii2009), (The Physical Society of Japan, Americal Physical Society), Hawaii, USA, Oct. (2009).
Baba H., Ichihara T., Ohnishi T., Takeuchi S., YoshidaK., Watanabe Y., Ota S., and Shimoura S.: “The New
DAQ System in RIKEN RIBF”, 3rd Joint Meeting of the
Nuclear Physics Divisions of the APS and JPS (Hawaii2009), Hawaii, USA, Oct. (2009).
Akiba Y.: “Enhanced production of direct photons in√
Au+Au collisions at sNN =200 GeV and implications
for the initial temperature”, APS April Meeting 2010,(American Physical Society), Washington DC, USA,
Feb. (2010).
()Conference)(Domestic
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
, Beer G.
A.,, Choi S.,,, Buehler P., Hirtl
A., Cargnelli M., Kienle P., Marton J., Widmann E.,
Zmeskal J., Curceanu C. O., Guaraldo C., Iliescu M.,
Pietreanu D., Sirghi D., Sirghi F., Faso D., Busso L.,
Morra O.: “K
3
”,
2007
,
,
(2007).
3
,
,
,
: “
QCD
”,
- ,(
),
, 8 (2008).
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
, Beer G. A.,, Choi,, Buehler P., Cargnelli M., Hirtl A.,S.,
Kienle P., Marton J., Widmann E., Zmeskal J.,,
Curceanu C. O., Guaraldo C., Iliescu M., Pietreanu D.,- 421 -

Sirghi D., Sirghi F., Faso D., Morra O., Busso L.: “K
3
III”,
2008
,
, 9 (2008).
,
,
,
: “
QCD
”,
2008,

, 10
(2008).
,,,: “Hyperon Potentials from Lattice QCD”, Aizu meeting 2009 on Spin
Excitations and Exotic Degree of Freedom in Nuclei and
Nuclear Matter,, 2 (2009).
,
,
,
: “
QCD
”,

,
,2
(2009).
: “Mesons in dense matter”,
64,(),, 3 (2009).
,
,
,
: “
QCD
ΛN
”,
64
,(
),
, 3 (2009).
: “Experimental study of vector-meson modiﬁcation in nuclei”, Workshop “Photons and Leptons in
Hot/Dense QCD”, (),,3(2009).
,
,
,
: “
QCD
”,
A02
,
,

,

,

”,
),
, 5 (2009).
: “J-PARC E16”,, 3 (2009).
,
: “
30keV
65
,(

“
”, (
),

,
MUSASI, 11,,(2009).
,”,

8: “JRR-3,, 12(2009).
: “
GCOE

”,
,(
),

,

,
,

,

,

,
,

8

Li
,
,
,
,
,

,2
,
,

(2010).
,
,

,

,
,
,
: “KEK-TRIAC”,, 3 (2010).
, Behr J. A.,,,, Levy P.,
,
,
,
,
,
, Pearson M.,
,

,
,

,

,
65
,
,
,
,

3

,

8

: “
”,
,

Li
6
,3

(2010).

- 422 -

4

Advanced
RNC Meson Science Laboratory
Publications
Publications[Journal](Original Papers) *Subject to Peer Review
Nagae D., Asahi K., Ueno H., Kameda D., Takemura
M., Takase T., Yoshimi A., Sugimoto T., Nagatomo T.,
Kobayashi Y., Uchida M., Shimada K., Arai T., Inoue
T., Kagami S., and Hatakeyama N.: “Measurement ofElectric Quadrupole Moments for 31Al Using Spin Polarized RI Beams”, AIP Conf. Proc. 915, 853–856(2007).
Shimada K., Nagae D., Asahi K., Arai T., Takemura
M., Inoue T., Takase T., Kagami S., HatakeyamaN., Kobayashi Y., Ueno H., Yoshimi A., Kameda D.,
Nagatomo T., Sugimoto T., Kubono S., Yamaguchi H.,
Wakabayashi Y., Amadio G., Hayakawa S., Murata J.,
and Kawamura H.: “Production of Polarized Radioactive Beams via The Inverse-kinematics Reactions andTheir Applications”, AIP Conf. Proc. 915, 857–860(2007).
Adare A., Akiba Y., Aoki K., Asai J., Bazilevsky A. V.,
Bunce G. M., Deshpande A., Enyo H., Fields D. E.,
Fox B., Fujiwara K., Fukao Y., Goto Y., Gross P. M.,
Hasuko K., Heuser J. M., Horaguchi T., Ichihara T.,
Imai K., Inoue Y., Ishihara M., Jinnouchi O., KamiharaN., Kaneta M., Kanoh H., Kawall D., Kiyomichi A.,
Kobayashi H., Kurita K., Mao Y., Murata J., Nakagawa
I., Nakano K., Onishi H., Okada H., Okada K., Rykov V.
L., Saito N., Sato H., Shibata T., Shoji K., Tabaru T.,
Taketani A., Tanida K., Togawa M., Tojo J., Torii H.,
Wagner M. M., Watanabe Y., Xie W., and Yokkaichi
S.: “Cold Nuclear Matter Eﬀects on J/ψ Production as Constrained by Deuteron-Gold Measurements at√
sNN = 200 GeV”, Phys. Rev. C 77, 024912-1–02491215 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K., Fukao
Y., Goto Y., Gross P. M., Hachiya T., Hasuko K., Heuser
J. M., Horaguchi T., Ichihara T., Imai K., Inoue Y.,
Ishihara M., Jinnouchi O., Kajihara F., Kamihara N.,
Kaneta M., Kanoh H., Kawall D., Kiyomichi A., Kurita
K., Mao Y., Murata J., Nakagawa I., Nakano K., Onishi
H., Okada H., Okada K., Rykov V. L., Saito N., Sato H.,
Shibata T., Shoji K., Tabaru T., Taketani A., Tanida K.,
Togawa M., Tojo J., Torii H., Tsuchimoto Y., Wagner
M. M., Watanabe Y., Xie W., and Yokkaichi S.: “Quantitative Constraints on the Transport Properties of Hot
Partonic Matter from Semi-Inclusive Single High Transverse Momentum Pion Suppression in Au+Au Collisions√
at sNN = 200 GeV”, Phys. Rev. C 77, 064907-1–
064907-12 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K., Fukao
Y., Goto Y., Gross P. M., Hachiya T., Hasuko K., Heuser

J. M., Horaguchi T., Ichihara T., Imai K., Inoue Y.,
Ishihara M., Jinnouchi O., Kajihara F., Kamihara N.,
Kaneta M., Kanoh H., Kawall D., Kiyomichi A., Kurita
K., Mao Y., Murata J., Nakagawa I., Nakano K., Onishi
H., Okada H., Okada K., Rykov V. L., Saito N., Sato H.,
Shibata T., Shoji K., Tabaru T., Taketani A., Tanida K.,
Togawa M., Tojo J., Torii H., Tsuchimoto Y., Wagner
M. M., Watanabe Y., Xie W., and Yokkaichi S.: “Dihadron azimuthal correlations in Au+Au collisions at√
sNN = 200 GeV”, Phys. Rev. C 78, 014901-1–01490142 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bazilevsky A. V.,
Bunce G. M., Deshpande A., Enyo H., Fields D. E.,
Fox B., Fujiwara K., Fukao Y., Goto Y., Gross P. M.,
Hachiya T., Hasuko K., Heuser J. M., Horaguchi T.,
Ichihara T., Imai K., Inoue Y., Ishihara M., Jinnouchi
O., Kajihara F., Kamihara N., Kaneta M., Kanoh H.,
Kawall D., Kiyomichi A., Kobayashi H., Kurita K., Mao
Y., Murata J., Nakagawa I., Nakano K., Onishi H.,
Okada H., Okada K., Rykov V. L., Saito N., Sato H.,
Shibata T., Shoji K., Tabaru T., Taketani A., Tanida
K., Togawa M., Tojo J., Torii H., Tsuchimoto Y.,
Wagner M. M., Watanabe Y., Xie W., and Yokkaichi
S.: “Charged hadron multiplicity ﬂuctuations in Au+Au√
and Cu+Cu collisions from sNN = 22.5 to 200 GeV”,
Phys. Rev. C 78, 044902-1–044902-15 (2008).
Afanasiev S., Akiba Y., Aoki K., Bunce G. M., DeshpandeA., Enyo H., Fields D. E., Fukao Y., Goto Y., Gross P.
M., Hachiya T., Hasuko K., Heuser J. M., Horaguchi
T., Ichihara T., Imai K., Ishihara M., Jinnouchi O.,
Kajihara F., Kamihara N., Kaneta M., Kiyomichi A.,
Kurita K., Murata J., Onishi H., Okada H., Okada K.,
Rykov V. L., Saito N., Sato H., Shibata T., Shoji K.,
Tabaru T., Taketani A., Tanida K., Togawa M., TojoJ., Torii H., Tsuchimoto Y., Wagner M. M., WatanabeY., Xie W., and Yokkaichi S.: “Source breakup dynam√
ics in Au+Au Collisions at sNN =200 GeV via threedimensional two-pion source imaging”, Phys. Rev. Lett.
100, 232301-1–232301-6 (2008).
Afanasiev S., Akiba Y., Aoki K., Bunce G. M., DeshpandeA., Enyo H., Fields D. E., Fukao Y., Goto Y., Gross P.
M., Hachiya T., Hasuko K., Heuser J. M., Horaguchi
T., Ichihara T., Imai K., Ishihara M., Jinnouchi O.,
Kajihara F., Kamihara N., Kaneta M., Kiyomichi A.,
Kurita K., Murata J., Onishi H., Okada H., Okada K.,
Rykov V. L., Saito N., Sato H., Shibata T., Shoji K.,
Tabaru T., Taketani A., Tanida K., Togawa M., Tojo J.,
Torii H., Tsuchimoto Y., Wagner M. M., Watanabe Y.,
Xie W., and Yokkaichi S.: “Particle-species dependent
modiﬁcation of jet-induced correlations in Au+Au col√lisions at sNN = 200 GeV”, Phys. Rev. Lett. 101,
082301-1–082301-6 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K., Fukao
Y., Goto Y., Gross P. M., Horaguchi T., Ichihara T.,- 423 -

1

Imai K., Inoue Y., Ishihara M., Jinnouchi O., KamiharaN., Kaneta M., Kanoh H., Kawall D., Kiyomichi A.,
Kurita K., Mao Y., Murata J., Nakagawa I., Nakano
K., Onishi H., Okada H., Okada K., Rykov V. L.,
Saito N., Shibata T., Shoji K., Tabaru T., Taketani A.,
Tanida K., Togawa M., Tojo J., Torii H., Wagner M.
M., Watanabe Y., Xie W., and Yokkaichi S.: “J/ψ Pro√
duction in sNN = 200 GeV Cu+Cu Collisions”, Phys.
Rev. Lett. 101, 122301-1–122301-6 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Dairaku S., Deshpande A., Enyo H., Fields D. E.,
Fujiwara K., Fukao Y., Goto Y., Gross P. M., Horaguchi
T., Ichihara T., Ichimiya R., Imai K., Inoue Y., Ishihara
M., Jinnouchi O., Kametani S., Kamihara N., Kaneta
M., Kanoh H., Kawall D., Kiyomichi A., Kurita K.,
Kurosawa M., Li Z., Mao Y., Murata J., Nakagawa I.,
Nakano K., Onishi H., Okada H., Okada K., Onuki Y.,
Rykov V. L., Saito N., Sakashita K., Shibata T., Shoji
K., Tabaru T., Taketani A., Tanida K., Togawa M.,
Tojo J., Torii H., Wagner M. M., Watanabe Y., Xie W.,
and Yokkaichi S.: “Onset of π 0 suppression studied in√
Cu+Cu collisions at sNN = 22.4, 62.4, and 200 GeV”,
Phys. Rev. Lett. 101, 162301-1–162301-6 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K.,
Fukao Y., Goto Y., Gross P. M., Hachiya T., Hasuko K.,
Heuser J. M., Horaguchi T., Ichihara T., Imai K., Inoue
Y., Ishihara M., Jinnouchi O., Kajihara F., KamiharaN., Kaneta M., Kanoh H., Kawall D., Kiyomichi A.,
Kurita K., Mao Y., Murata J., Nakagawa I., Nakano K.,
Onishi H., Okada H., Okada K., Rykov V. L., Saito N.,
Sato H., Shibata T., Shoji K., Tabaru T., Taketani A.,
Tanida K., Togawa M., Tojo J., Torii H., Tsuchimoto Y.,
Wagner M. M., Watanabe Y., Xie W., and Yokkaichi S.:“Suppression pattern of neutral pions at high transverse√
momentum in Au+Au collisions at sNN = 200 GeV
and constraints on medium transport coeﬃcients”, Phys.
Rev. Lett. 101, 232301-1–232301-7 (2008).
Asahi K., Ueno H., Shimada K., Nagatomo T., Yoshimi
A., Nagae D., Kameda D., Uchida M., Inoue T.,
Hatakeyama N., Kagami S., Hasama Y., Suzuki K.,
Murata J., Kawamura H., Narita K., and Ishihara M.:“Nuclear Structure Studies with Polarized Radioactive
Beams”, AIP Conf. Proc. 1149, 90–99 (2009).
Nagatomo T., Shimada K., Asahi K., Balabanski D. L.,
Daugas J., Depuydt M., De
Rydt M., Gaudefroy L.,
Grevy S., Hasama Y., Ichikawa Y., Kameda D., MorelP., Perrot L., Stodel C., Thomas J. C., VanderheijdenW., Vermeulen N., Vingerhoets P., Yoshimi A., Neyens
G., and Ueno H.: “Electric quadrupole moment of theneutron-rich 33 Al”, Eur. Phys. J. A 42, No. 3, pp.
383–385 (2009).
Imao H., Ishida K., Kawamura N., Matsuzaki T., Matsuda
Y., Toyoda A., Strasser P., Iwasaki M., and NagamineK.: “Density eﬀect in d-d muon-catalyzed fusion withortho- and para-enriched deuterium”, Hyperﬁne Interact. 193, No. 1-3, pp. 159–163 (2009).
Koike T. and Harada T.: “The K̄N → πΣ decay threshold
eﬀect in 3 He(in-ﬂight K − ,n) reaction spectrum”, Hyperﬁne Interact. 193, 221–227 (2009).
Imao H., Hassan T. A., Michishio K., Enomoto Y.,
Shimoyama T., Kanai Y., Kuroda N., Mohri A., Higaki
H., Saitoh H., Torii H., Nagata Y., Toyoda H., Matsuda
Y., Nagashima Y., and Yamazaki Y.: “ASACUSAMUSASHI: New progress with intense ultra slow antiproton beam”, Hyperﬁne Interact. 194, No. 1-3, pp.
71–76 (2009).
Koike T. and Harada T.: “FORMATION OF DEEPLYBOUND K − pp STATE IN 3 He(IN-FLIGHT K − , n) REACTION SPECTRUM”, Int. J. Mod. Phys. A 24, No.
11, pp. 2126–2133 (2009).
Kawamata T., Sugawara N., Uesaka M., Kaneko N.,
Kajiwara T., Yamane H., Koyama K., Kudo K.,
Kobayashi N., and Koike Y.: “Single-Crystal Growthof Pb2 V3 O9 and the Bose-Einstein Condensed Stateof Triplons Studied by Thermal Conductivity, Speciﬁc
Heat and Magnetization Measurements”, J. Phys.: Con.
Ser. 150, 042087-1–042087-4 (2009).
Adachi T., Haidar S. M., Kawamata T., Sugawara N.,
Kaneko N., Uesaka M., Sato H., Tanabe Y., Noji T.,
Kudo K., Kobayashi N., and Koike Y.: “Thermalconductivity study on the electronic state in the overdoped regime of La2−x Srx CuO4 : Phase separation andanomaly at x ∼ 0.21”, J. Phys.: Con. Ser. 150, 0521151–052115-4 (2009).
Oosawa A., Suzuki T., Kanada K., Kojima S.,
Goto T., and Manaka H.: “1 H-NMR Spin-Lattice
Relaxation Rate of the Quantum Spin System(CH3 )2 CHNH3 Cu(Clx Br1−x )3 with x = 0 and 0.35”, J.
Phys. Soc. Jpn. 78, No. 5, pp. 053702-1–053702-4(2009).
Yagi E., Yoshii M., Okada Y., Matsuba H., Miyahara K.,
Koike S., Sugawara T., Shishido T., and Ogiwara K.:“Site change of hydrogen in niobium on alloying withoversized Ta atoms”, J. Phys. Soc. Jpn. 78, No. 6, pp.
064601-1–064601-8 (2009).
Suzuki T., Yamada F., Watanabe I., Matsuzaki T., Goto
T., Oosawa A., and Tanaka H.: “Spin ﬂuctuationsin the ground state of doped quantum spin system
TlCu1−x Mgx Cl3 with x = 0.0047 probed by muon-spinrelaxation technique”, J. Phys. Soc. Jpn. 78, No. 7,
pp. 074705-1–074705-5 (2009).
Koike T. and Harada T.: “3 He(K − , n) REACTION
SPECTRUM NEAR THE K̄N → πΣ DECAYTHRESHOLD AND THE DEEPLY-BOUND K − pp
STATE”, Mod. Phys. Lett. A 24, No. 11/13, pp.
911–914 (2009).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K., Fukao
Y., Goto Y., Gross P. M., Horaguchi T., Ichihara T.,- 424 -

2

Imai K., Inoue Y., Ishihara M., Jinnouchi O., KamiharaN., Kaneta M., Kanoh H., Kawall D., Kiyomichi A.,
Kurita K., Mao Y., Murata J., Nakagawa I., Nakano K.,
Onishi H., Okada H., Okada K., Rykov V. L., Saito N.,
Shibata T., Shoji K., Tabaru T., Taketani A., Tanida K.,
Togawa M., Tojo J., Torii H., Wagner M. M., WatanabeY., Xie W., and Yokkaichi S.: “Dilepton mass spectra√in p+p collisions at s = 200 GeV and the contribution
from open charm”, Phys. Lett. B 670, 313–320 (2009).
De Rydt M., Neyens G., Asahi K., Balabanski D. L.,
Daugas J., Depuydt M., Gaudefroy L., Grevy S.,
Hasama Y., Ichikawa Y., Morel P., Nagatomo T.,
Ohtsuka T., Perrot L., Shimada K., Stoedel C., ThomasJ., Ueno H., Utsuno Y., Wannes V., Vermeulen N.,
Vingerhoets P., and Yoshimi A.: “Precision measurement of the electric quadrupole moment of 31 Al anddetermination of the eﬀective proton charge in the sdshell”, Phys. Lett. B 678, 344–349 (2009).
Andresen G. B., Bertsche W., Bray C. C., Butler E., Cesar
C. L., Chapman S., Charlton M., Fajans J., Fujiwara
M., Gill D. R., Hardy W. N., Hayano R., Hayden M.
E., Humphries A. J., Hydomako R., Jorgensen L. V.,
Kerrigan S. J., Keller J., Kurchaninov L., Lamb R.,
Madsen N., Nolan P., Olchansk K., Olin A., Povilus
A., Pusa P., Robicheaux F., Sarid E., Seif El Nasr
S., Silveira D. M., Storey J. W., Thompson R. I.,
van der Werf D. P., Wurtele J. S., and Yamazaki Y.:“Magnetic multipole induced zero-rotation frequency
bounce-resonant loss in a Penning-Malmberg trap used
for antihydrogen trapping”, Phys. Plasmas 16, No. 10,
pp. 100702-1–100702-4 (2009).
Suzuki T., Yamada F., Kawamata T., Watanabe I.,
Goto T., and Tanaka H.: “Quantum critical behavior in highly random system Tl1−x Kx CuCl3 probed byzero- and longitudinal-ﬁeld muon-spin-relaxation measurements”, Phys. Rev. B 79, 104409-1–104409-5(2009).
Inoue H., Tani S., Hosoya S., Inokuchi K., Fujiwara T.,
Saito T., Suzuki T., Oosawa A., Goto T., Fujisawa
M., Tanaka H., Sasaki T., Awaji S., Watanabe K.,
and Kobayashi N.: “63/65 Cu- and 35/37 Cl-NMR Studies of Triplet Localization in the Quantum Spin System NH4 CuCl3 ”, Phys. Rev. B 79, 174418-1–174418-7(2009).
Suzuki T., Watanabe I., Yamada F., Ishii Y., Ohishi
K., Risdiana ., Goto T., and Tanaka H.: “Evidence for continuous change of spin states between
impurity-induced order and pressure-induced order in
TlCu0.985 Mg0.015 Cl3 probed via muon spin rotation”,
Phys. Rev. B 80, 064407-1–064407-5 (2009).
Ohishi K., Heﬀner R. H., Ito T. U., Higemoto W., Morris
G. D., Hur H., Bauer E. D., Sarrao J. L., Thompson
J. D., MacLaughlin D. E., and Shu L.: “Developmentof the heavy-fermion state in Ce2 IrIn8 and the eﬀects

of Ce dilution in (Ce1−x Lax )2 IrIn8 ”, Phys. Rev. B 80,
125104-1–125104-7 (2009).
Koike T. and Harada T.: “Deeply bound K − pp state in
the 3 He(in-ﬂight K − ,n) spectrum, and its moving polenear the πΣN threshold”, Phys. Rev. C 80, 055208-1–
055208-14 (2009).
Ito T. U., Higemoto W., Ohishi K., Nishida N., Heﬀner
R. H., Yuji A., Amato A., Onimaru T., and Suzuki H.
S.: “Quantized Hyperﬁne Field at an Implanted µ+ in
PrPb3 : Interplay between Localized f electrons and Interstitial Charged Particle”, Phys. Rev. Lett. 102,096403-1–096403-4 (2009).
Yokoyama K., Nagamine K., Simomura K., Tom H. W.,
Roland K. K., Bakule P., Matsuda Y., Pratt F. L.,
and Torikai E.: “Muons for spintronics: photo-induced
conduction electron polarization in n-type GaAs observed by the muonium method”, Physica B 404, No.
5-7, pp. 856–858 (2009).
Satoh K., Fujita H., Katayama K., Taniguchi H.,
Ito T. U., Ohishi K., and Higemoto W.: “µSRstudy of an layered organic superconductor κ-(BEDTTTF)4 Hg2.89 Br8 ”, Physica B 404, 597–599 (2009).
Satoh K., Sato K., Yoshida T., Taniguchi H., Goko T.,
Ito T. U., Ohishi K., and Higemoto W.: “µSR studyof organic antiferromagnet β � -(BEDT-TTF)2 ICl2 underhigh pressure”, Physica B 404, 600–602 (2009).
Ohishi K., Heﬀner R. H., Spehling J., MacDougall G.
J., Ito T. U., Higemoto W., Amato A., Andreica
D., Nieuwenhuys G., Klauss H. H., Luke G. M.,
Thompson J. D., Bianchi A. D., and Fisk Z.: “Magnetism and superconductivity in heavy fermion superconductor CeCo(In0.97 Cd0.03 )5 ”, Physica B 404, 754–
756 (2009).
Yuji A., Higemoto W., Tsunashima Y., Yonezawa Y.,
Satoh K., Koda A., Ito T. U., Ohishi K., Heﬀner R.
H., Kikuchi D., and Sato H.: “Weak ferromagnetic ordering in the anomalous ﬁeld-insensitive heavy-fermion
state in SmOs4 Sb12 ”, Physica B 404, 757–760 (2009).
Ito T. U., Higemoto W., Ohishi K., Heﬀner R. H.,
Nishida N., Satoh K., Sugawara H., Yuji A., Kikuchi D.,
and Sato H.: “Possible low-energy excitations of multipoles in SmRu4 P12 probed by muon spin relaxation”,
Physica B 404, 761–764 (2009).
(Review)
,
,
: “
X
”,
44, 719–725(2009).
[Book • Proceedings
Proc.](Original Papers) *Subject to Peer Review
Ishida K., Matsuzaki T., Imao H., Matsuda Y., Iwasaki
M., Nagamine K., Kawamura N., Kato M., Sugai H.,
and Eaton G. H.: “Muon Catalyzed d-t Fusion in Nonequilibrated Mixtures of T2 with Normal, Ortho andPara-rich D2”, International Conference on Muon Cat-

- 425 -

3alyzed Fusion and Related topics Proceedings (µCF-07),
Dubna, Russia, 2007–6, Joint Institute for Nuclear Research, Dubna, pp. 99–104 (2008).

Oral Presentations
Oral Presentations((International) Conference etc.)
Inoue H., Tani S., Hosoya S., Suzuki T., Goto T., Tanaka
H., Sasaki T., and Kobayashi N.: “2 D, 35/37 Cl, 63/65 CuNMR study on quantum spin system NH4 CuCl3 ”, 24th
International Conference on Low Temperature Physics(LT24), Orlando, USA, Aug. (2005).
Tonishi J., Suzuki T., and Goto T.: “Anomalous change
of Hall coeﬃcient in overdoped La2−x Srx Cu1−y Zny O4around x = 0.2”, 24th International Conference on
Low Temperature Physics (LT24), Orlando, USA, Aug.
(2005).
Goto T., Ueda M., Sumikawa H., Suzuki T., Fujita M.,
Yamada K., Koike Y., and Adachi T.: “Backling of
the CuO2 plane in single crystals of La-based high-Tc
cuprates observed by NMR”, 24th International Conference on Low Temperature Physics (LT24), Orlando,
USA, Aug. (2005).
Kanada K., Saito T., Oosawa A., Goto T., Suzuki T.,
and Manaka H.: “Magnetic order in the solid solutionof two spin-gap systems (CH3 )2 CHNH3 Cu(Cl1−x Brx )3 ”,
ICM2006 Satellite Conference: 1st International Symposium of Quantum Beam Science Directorate of JAEA,
Advances in Neutron, Synchrotron Radiation, µSR
and NMR Researches (QuBS2006), Tokai-mura, Ibaraki
Pref., Aug. (2006).
Fujiwara T., Oosawa A., Tsunoda R., Goto T., SuzukiT., Shindo Y., Tanaka H., Sasaki T., Kobayashi N.,
Awaji S., and Watanabe K.: “Cu-NMR Study on disordered dimer system (Tl1−x Kx )CuCl3 with the Boseglass ground state”, Yamada Conference LX on Researchin High Magnetic Fields (RHMF2006), Sendai, Aug.
(2006).
Tonishi J., Ueda M., Suzuki T., Oosawa A., Goto T.,
Adachi T., Koike Y., Fujita M., and Yamada K.: “Local structure in single crystals of La-based High Tc
Cuprates”, Yamada Conference LX on Research in High
Magnetic Fields (RHMF2006), Sendai, Aug. (2006).
Oosawa A., Suzuki T., Watanabe I., Goto T.,
and Manaka H.: “µSR-detected Softmode toward a
Possible Phase Transition in disordered spin gap system (CH3 )2 CHNH3 -Cu(Clx Br1−x )3 ”, 11th International
Conference on Muon Spin Rotation, Relaxation and Resonance (µSR2008), Tsukuba, July (2008).
Yokoyama K., Nagamine K., Simomura K., Tom H.
W., Roland K. K., Bakule P., Matsuda Y., Pratt F.
L., and Torikai E.: “Muons for spintronics: Polarized conduction electrons in GaAs observed by spin
exchange scattering of muonium”, 11th International
Conference on Muon Spin Rotation, Relaxation andResonance (µSR2008), (International Society for MuSR

Spectroscopy), Tsukuba, July (2008).
Kousaka Y., Ohsumi H., Komesu T., Arima T., Sakai
S., Akita M., Inoue K., Yokobori T., Nakao Y., KayaE., and Akimitsu J.: “Crystallographic Chirality in
CsCuCl3 Investigated by Rosonant Circularly-polarized
X-ray Scattering”, 2nd International Symposium on
Anomalous Quantum Materials (ISAQM2008) and the
7th Asia-Paciﬁc Workshop, (Invention of Anomalous
Quantum Materials), Tokyo, Nov. (2008).
Ishida K.: “Ultra slow muon source for new g-2 experiment”, 11th International Workshop on Neutrino Factories, Superbeams and Beta Beams (NuFact09), (Illinois
Institute of Technology), Chicago, USA, July (2009).
Ishida K., Miller J., and Nicolo D.: “WG4 Summary”,
11th International Workshop on Neutrino Factories, Superbeams and Beta Beams (NuFact09), (Illinois Institute of Technology), Chicago, USA, July (2009).
Yamazaki Y., Enomoto Y., Kuroda N., Mohri A., Matsuda
Y., Higaki H., Kira K., Kanai Y., Imao H., ShimoyamaT., Michishio K., Torii H., Nagata Y., NagashimaY., and saitoh H.: “Developments of the cusp trap tosynthesize antihydrogen atoms for high precision spectroscopy of ground state hyperﬁne splitting”, 26th International Conference on Photonic, Electronic, andAtomic Collisions (ICPEAC 2009), (Western Michigan
University), Kalamazoo, USA, July (2009).
Nakajima S., Goto T., Suzuki T., Watanabe I.,
and Manaka H.:“µSR and NMR Study on
Quantum Critical Point in Quantum Spin Ladder(CH3 )2 CHNH3 Cu(Clx Br1−x )3 ”, International Conference on Magnetism (ICM 2009), Karlsruhe, Germany,
July (2009).
Goto T., Suzuki T., Nakajima S., Kanada K., Saito T.,
Watanabe I., Luetkens H., and Amato A.: “µSR study
on the ground state of bond-disordered spin gap system(CH3 )2 CHNH3 Cu(Cl1−x Brx )3 (x = 0.95, 0.88)”, International Conference on Magnetism (ICM 2009), Karlsruhe, Germany, July (2009).
Kawamata T., Kaneko N., Uesaka M., Sato M., and Koike
Y.: “Enhancement of Thermal Conductivity due toSpinons in the One-Dimensional Spin System SrCuO2 ”,
International Conference on Magnetism (ICM 2009),(Universitat Karlsruhe), Karlsruhe, Germany, July(2009).
Suzuki T., Watanabe I., Yamada F., Ishii Y., Ohishi K.,
Risdiana ., Goto T., and Tanaka H.: “Pressure eﬀect onmagnetic ground states in Tl(Cu1−x Mgx )Cl3 probed bymuon-spin-rotation”, International Conference on Magnetism (ICM 2009), Karlsruhe, Germany, July (2009).
Uesaka M., Kawamata T., Kaneko N., Sato M., Kudo K.,
Kobayashi N., and Koike Y.: “Quasi One-Dimensional
Spin System Thermal Conductivity of the Sr2 V3 O9 ”, International Conference on Magnetism (ICM 2009), (Universitat Karlsruhe), Karlsruhe, Germany, July (2009).
Sato M., Kawamata T., Sugawara N., Kaneko N., Uesaka- 426 -

4

M., Kudo K., Kobayashi N., and Koike Y.: “Thermal Conductivity in the Bose-Einstein Condensed Stateof Triplons in the Bond-Alternating Spin-Chain System Pb2 V3 O9 ”, International Conference on Magnetism(ICM 2009), (Universitat Karlsruhe), Karlsruhe, Germany, July (2009).
Koike T. and Harada T.: “3 He(in-ﬂight K − , n) spectrum and moving pole of a deeply-bound K − pp state incomplex energy plane”, 10th International Conference
on Hypernuclear and Strange Particle Physics (Hyp-X),(Kyoto university, the Global COE Program), Tokaimura, Ibaraki Pref., Sept. (2009).
Ohishi K., Ito T. U., Higemoto W., Uehara A., Kozawa K.,
Yamazaki T., Kimishima Y., and Uehara M.: “Quasiparticle Excitations in Newly Discovered Antiperovskite
Superconductor ZnNNi3 ”, 9th International Conference
on Materials and Mechanisms of Superconductivity(M2S-IX), Tokyo, Sept. (2009).
Sakuma F.: “Double anti-kaon production in nucleus by
Stopped Anti-proton Annihilation”, International Workshop on Physics and Upgrade of the J-PARC Hadron Facility, (RCNP), Tokai-mura, Ibaraki Pref., Sept. (2009).
Sakuma F.: “Development of the Cylindrical Detector System for an experimental search for kaonic nuclei at JPARC”, 3rd Joint Meeting of the Nuclear Physics Divisions of the APS and JPS (Hawaii 2009), Hawaii, USA,
Oct. (2009).
Ohishi K., Suzuki T., Heﬀner R. H., Ito T. U., HigemotoW., Bauer E. D., and Thompson J. D.: “Magnetism and muon Knight shift measurements in heavy
fermion compound Ce2 Rh(In,Sn)8”, Advanced Science Research Symposium 2009 (ASR2009): Positron,
Muon and other exotic particle beams for materials
and atomic/molecular sciences, (Japan Atomic Energy
Agency), Tokaimura, Nov. (2009).
Imao H., Michishio K., Kanai Y., Kuroda N., Enomoto
Y., Higaki H., Kira K., Mohri A., Torii H., Nagata Y.,
Kim C., Matsuda Y., Nagashima Y., and Yamazaki Y.:“Positron Accumulation and Manipulation for Antihydrogen Synthesis”, Advanced Science Research Symposium 2009 (ASR2009): Positron, Muon and other exotic
particle beams for materials and atomic/molecular sciences, (Japan Atomic Energy Agency), Tokaimura, Nov.
(2009).
Ishii Y., Watanabe I., Ito M., Matsuo T., Kobayashi Y.,
Matsuzaki T., and Tamao K.: “µSR studies of linear
two-coordinate iron complexes”, RIKEN Symposium on
Molecular Ensemble 2009, Wako, Dec. (2009).
Risdiana ., Fitrilawati .., Siregar R., Hidayat R., Nugroho
A. A., Tjia M., Ishii Y., and Watanabe I.: “Muonspin-relaxation study of spin dynamics in poly(3alkylthiophene)”, RIKEN Symposium on Molecular Ensemble 2009, Wako, Dec. (2009).
((Domestic)Conference), Beer G. A.,, Cargnelli M.,, Choi- 427 -

S., Curceanu C. O.,
,
,
,
,
,
,
,
,
,
, Juhasz B., Kienle P., Marton J.,,,, Schmid P.,,,,,, Widmann E.,,,
Zmeskal J.:,, 5 (2005).
,
,
,
,
,
,
,
,
,
: “F-AF(CH3 )CHNH3 CuCl3
Cl-NMR”,
2005,, 9 (2005).
,
,
,
,
,
,
: “
NMR III”,
2005,, 9 (2005).
,
,
,
,
,
,
,
: “
κ-(BEDTTTF)2 Cu(NCS)2
”,
2005
,
, 9 (2005).
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
, Bhang H., Choi S., Kim J., Yim H.,,
Widmann E., Kienle P.: “4 He(K−stopped ,N)
1 ”,
61
,(
),
,3
(2006).
, Beer G. A.,, Cargnelli M.,, Choi,,,S., Curceanu C. O.,
,
,
,
,
,
,
, Juhasz B., Kienle P., Marton J.,,,, Schmid P.,,,,,, Widmann E.,,,
Zmeskal J.: “K
3d→2p X”,
61,
, 3 (2006).
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
, Choi S.,,,
Cargnelli M., Juhasz B., Kienle P., Marton J., Widmann
E., Zmeskal J., Schmid P., Beer G. A., Curceanu C. O.:
“K
X
I”,
61
,
, 3 (2006).
,
,
,
,
,
,
,
,
: “La
”,
61
,
,3
(2006).
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
, Bhang H., Choi S., Kim J., Yim H.,,,N)
Widmann E., Kienle P.: “4 He(K−stopped
4 ”,
2006
,(
),
, 9 (2006).
,
,
,
,
,
,
,
,
: “La2−x Srx CuO4

5

”,
,
,
,
(2006).
,
“
2006
,
3

,9
,
,
”,

(2006).
,
: “

,
2006

2006
,

,
IPA-CuCl3
,
,9

,
,
,
,
IPACu(Clx Br1−x )3µSR”,,, 9 (2006).
: “K
”,
2006,

:

, 12
(2006).
, Beer G. A.,, Buehler P., Cargnelli M.,, Choi S., Curceanu C. O.,, Guaraldo C.,,, Hirtl A.,, Iliescu M.,
,
,
,
,
,
, Kienle P.,
Marton J.,,,, Pietreanu D.,,,,
Sirghi D., Sirghi F.,, Widmann E.,,, Zmeskal J.: “Precision spectroscopy of Kaonic Helium-3 3d→2p X-rays(J-PARC E17
)”,
2006,
, 12
(2006).
: “Dilepton measurement at CERN/SPS”,
2007
, (
),
,3
(2007).
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
, Bhang H., Choi S., Kim J., Yim H.,,,N)
Widmann E., Kienle P.: “4 He(K−stopped
(6)”,
2007
,(
),
, 3 (2007).
:
2007
,(
),
, 3 (2007).
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
, Beer G.
, Choi S.,,, Buehler P., Hirtl
A.,A., Cargnelli M., Kienle P., Marton J., Widmann E.,
Zmeskal J., Curceanu C. O., Guaraldo C., Iliescu M.,
Pietreanu D., Sirghi D., Sirghi F., Faso D., Busso L.,
Morra O.: “K
3
”,
2007
,
,
(2007).
3
,
,
,
,
,
,
,
,
: “NMR”,2007,, 3 (2007).
,
,
,
,
,
,
: “
IPA-Cu(Clx Br1−x )3
”,
2007
,
, 3 (2007).

- 428 -

, Beer G. A.,, Cargnelli M.,, ChoiS., Curceanu C. O.,
,
,
,
,
,
,
,
,
,
, Juhasz B., Kienle P., Marton J.,,,, Schmid P.,,,,,, Widmann E.,
,
,
62
,
, 9
Zmeskal J.:(2007).
,
,
,
,
,
,
,
: “
IPACuCl3”,62,, 9 (2007).
,
,
,
,
,
,
: “
IPACu(Cl0.35 Br0.65 )3
µSR”,
62
,
,9
(2007).
, Beer G. A.,, Buehler P., Cargnelli M.,, Choi S., Curceanu C. O.,, Guaraldo C.,,, Hirtl A.,, Iliescu M.,
,
,
,
,
,
, Kienle,,, Pietreanu
P., Marton J.,
D., Sirghi D., Sirghi F.,,,,, Widmann E.,,, Zmeskal J.: “JPARC
K
X
J-PARC E17”,
3(2007),, 11(2007).
: “

”,

,(
, 11
(2007).
: “”, RCNP
J-PARC,(),(2007).
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
, Bhang H., Choi S., Kim J., Yim H.,
K−
Widmann E., Kienle P.: “4 He
(1)”,
,3

63

,(

),

, 11
,
,
,
,

),

(2008).
,

,
,
,
,
,
: “J-PARC E15
K
veto
”,
63
,(
),
,3
(2008).
,,,,,:
IPA-Cu(Clx Br1−x )3
Cl-rich“1(x > 0.87)µSR
H-NMR”,
63,, 3 (2008).
,
,
,
,
: “
IPA-Cu(Cl0.35 Br0.65 )3
NMR”,

6

63
,

,
,

,

,

,

,

,
,

,
,

,

(2008).
,
,

,

,
,

,3
,

,

,

S/N
,

,
,

,
,

,
57

,

,
,
,
,
,
, Beer G. A.,, ChoiS.,,, Buehler P., Cargnelli M., Hirtl A.,
Kienle P., Marton J., Widmann E., Zmeskal J.,,
Curceanu C. O., Guaraldo C., Iliescu M., Pietreanu D.,
Sirghi D., Sirghi F., Faso D., Morra O., Busso L.: “K
3
III”,
2008
,
, 9 (2008).
,
,
,
,
,
,
: “
IPA-Cu(Cl ,
µSR”,
2008
Br)3
,
, 9 (2008).
: “”,
J-PARC,, 9 (2008).
,
,
,
,
,
,
,
,
,
,
,
,
: “µSR”, JST-TRIP
3
,(
),
, 12
(2008).
,,,,,:
Tl1−x Kx CuCl3 (x = 0.51, 0.60)
“
(µSR)
”,
64
,
, 3 (2009).
,,,, Saha S. R.,
,
,
,
: “
Ca2−x Nax CuO2 Cl2
II”,
64
,(
),
,
(2009).
3,,,,, Alex A.:
IPACu(Clx Br1−x )3“µSR II”,
64,, 3 (2009).
: “Nuclear astrophysics at J-PARC with asearch for deeply-bound kaonic nuclear states”, 2008
R
,(
,
),
, 3 (2009).
, Heﬀner R. H.,,, Bauer E. D., Graf
M. J., Zhu J. -., Morales L. A., Sarrao J. L., Morris G.
D., Fluss M. J., MacLaughlin D. E., Shu L.: “Muonspin rotation measurements of the superﬂuid density infresh and aged superconducting PuCoGa5 ”, Workshop
on Issues on Magnetic Penetration Depth Measurements
in Superconductors, (),, 4 (2009).
,
,
,
,
,
,
,
,
: “
57
Mn

”, 2009
,(
,
,

),
,

,9
,

: “

Mn

,

,9
,
,
57
Mn

53
(2009).
,,”, 200953(2009).
,
,

,(
,

,

),
,

,

: “

”, 200953,(),,9(2009).
Risdiana .: “µSR study of structure dependent electron
radical dynamics in polythiophene and its derivative”,
5th Program Advisory Committee Meeting for Materials
and Life Science experiments at RIKEN Nishina Center,,9(2009).
,,, Risdiana .,
,
,
,
,
: “
Tl(Cu1−x Mgx )Cl3 (x = 0.015)
”,
2009
,
, 9 (2009).
,
,
,
,
,
,
,
: “µSR
ZnNNi3
”,
2009
,(
),
, 9 (2009).
,,,,: “S = 1/2
Pb2 V3 O9
”,
2009
,
,9
(2009).
,
,
,
,
,
,
: “
Ru1.9 Fe0.1 CrSi µSR”,
2009,, 9 (2009).
,
,
,
,
,
,
,
,
: “
Pb2 V3 O9
ESR
II”,
2009
,
, 9 (2009).
,
,
,
,
,
:
Pb2 V3 O9
“
”,
2009
,
, 9 (2009).
,,,,, Alex A.:“
IPACu(Clx Br1−x )3µSR·NMR”,
2009,,9(2009).
,
,
,
,
,
,
,
,
: “
57
Mn
S/N
”,
21
II
,
, 12 (2009).
,
,
,
,
,
,
,
,
,
,
,
,
: “
X
”,
2009
,
, 12
(2009).
,
,
,
,
,
,

- 429 -

7

,

,

,
X

”,

,
: “
CsCuCl3

,

23

,
,1
(2010).
, Fleming D. G.: “Measurement of the
Bakule P.,
Chemical Reaction Rate of Muonium with StimulatedRaman-Pumped H2*(v=1) in the Gas”,-RAL
2009 ,,1(2010).
: “
µCF”,
-RAL
2009 ,, 1 (2010).
,,,, Heﬀner R. H., Bauer E.
D.: “R330,349: µSR Study around a Quantum Critical
Point in Heavy Fermion Compounds”,-RAL
2009 ,, 1 (2010).
: “
”,
-RAL
2009 ,,1(2010).
: “g-2”, RCNP
2,(),,2(2010).
,
,
,
,
,
,
,
,
,
,
: “

,
,
,
,
,
,
,
, Rizzini L. E., Venturelli
L., Zurlo N., Mascagna V.: “
”,
65
,(
),
, 3 (2010).
,
,
,
,
,
,
,
,
,
,
,
: “
”,
65
,
, 3 (2010).
,
,
,
,
,
,
57
,
,
: “
Mn
”,
11
,
, 3 (2010).

”,65, 3 (2010).
,
,
,
,
,
,
,
,
,
,
,
,
, Rizzini L. E., Venturelli L., Zurlo N.,
I
Mascagna V.: “
”,
65
,(
),
, 3 (2010).
,
,
,
,
,
,
,
,
,
,
,
,
,
,
: “
”,
65
,(
),
,3
(2010).
,,,,, Shirage,,: “µSRP. M.,
LaFeAs(O,H)
”,
65
,(
),
,3
(2010).
,
,
,
,
,
,
,
,
,
,
,
,
: “µSR(Ba,K)Fe2 As2Ba(Fe,Co)2 As2
”,
65
,(
),
, 3 (2010).
,
,
,
,
,
,
,
,
,
,
,
,
,
: “MUSASHI
”,
65
,(
),
,3
(2010).
,
,
,
,
,
,(

),

- 430 -

8

RIKEN BNL Research Center
RNC
Publications
Publications[Journal](Original Papers) *Subject to Peer Review
Adare A., Akiba Y., Aoki K., Asai J., Bazilevsky A. V.,
Bunce G. M., Deshpande A., Enyo H., Fields D. E.,
Fox B., Fujiwara K., Fukao Y., Goto Y., Gross P. M.,
Hasuko K., Heuser J. M., Horaguchi T., Ichihara T.,
Imai K., Inoue Y., Ishihara M., Jinnouchi O., KamiharaN., Kaneta M., Kanoh H., Kawall D., Kiyomichi A.,
Kobayashi H., Kurita K., Mao Y., Murata J., Nakagawa
I., Nakano K., Onishi H., Okada H., Okada K., Rykov V.
L., Saito N., Sato H., Shibata T., Shoji K., Tabaru T.,
Taketani A., Tanida K., Togawa M., Tojo J., Torii H.,
Wagner M. M., Watanabe Y., Xie W., and Yokkaichi
S.: “Cold Nuclear Matter Eﬀects on J/ψ Production as Constrained by Deuteron-Gold Measurements at√
sNN = 200 GeV”, Phys. Rev. C 77, 024912-1–02491215 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K., Fukao
Y., Goto Y., Gross P. M., Hachiya T., Hasuko K., Heuser
J. M., Horaguchi T., Ichihara T., Imai K., Inoue Y.,
Ishihara M., Jinnouchi O., Kajihara F., Kamihara N.,
Kaneta M., Kanoh H., Kawall D., Kiyomichi A., Kurita
K., Mao Y., Murata J., Nakagawa I., Nakano K., Onishi
H., Okada H., Okada K., Rykov V. L., Saito N., Sato H.,
Shibata T., Shoji K., Tabaru T., Taketani A., Tanida K.,
Togawa M., Tojo J., Torii H., Tsuchimoto Y., Wagner
M. M., Watanabe Y., Xie W., and Yokkaichi S.: “Quantitative Constraints on the Transport Properties of Hot
Partonic Matter from Semi-Inclusive Single High Transverse Momentum Pion Suppression in Au+Au Collisions√
at sNN = 200 GeV”, Phys. Rev. C 77, 064907-1–
064907-12 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K., Fukao
Y., Goto Y., Gross P. M., Hachiya T., Hasuko K., Heuser
J. M., Horaguchi T., Ichihara T., Imai K., Inoue Y.,
Ishihara M., Jinnouchi O., Kajihara F., Kamihara N.,
Kaneta M., Kanoh H., Kawall D., Kiyomichi A., Kurita
K., Mao Y., Murata J., Nakagawa I., Nakano K., Onishi
H., Okada H., Okada K., Rykov V. L., Saito N., Sato H.,
Shibata T., Shoji K., Tabaru T., Taketani A., Tanida K.,
Togawa M., Tojo J., Torii H., Tsuchimoto Y., Wagner
M. M., Watanabe Y., Xie W., and Yokkaichi S.: “Dihadron azimuthal correlations in Au+Au collisions at√
sNN = 200 GeV”, Phys. Rev. C 78, 014901-1–01490142 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bazilevsky A. V.,
Bunce G. M., Deshpande A., Enyo H., Fields D. E.,
Fox B., Fujiwara K., Fukao Y., Goto Y., Gross P. M.,
Hachiya T., Hasuko K., Heuser J. M., Horaguchi T.,
Ichihara T., Imai K., Inoue Y., Ishihara M., Jinnouchi

O., Kajihara F., Kamihara N., Kaneta M., Kanoh H.,
Kawall D., Kiyomichi A., Kobayashi H., Kurita K., Mao
Y., Murata J., Nakagawa I., Nakano K., Onishi H.,
Okada H., Okada K., Rykov V. L., Saito N., Sato H.,
Shibata T., Shoji K., Tabaru T., Taketani A., Tanida
K., Togawa M., Tojo J., Torii H., Tsuchimoto Y.,
Wagner M. M., Watanabe Y., Xie W., and Yokkaichi
S.: “Charged hadron multiplicity ﬂuctuations in Au+Au√
and Cu+Cu collisions from sNN = 22.5 to 200 GeV”,
Phys. Rev. C 78, 044902-1–044902-15 (2008).
Afanasiev S., Akiba Y., Aoki K., Bunce G. M., DeshpandeA., Enyo H., Fields D. E., Fukao Y., Goto Y., Gross P.
M., Hachiya T., Hasuko K., Heuser J. M., Horaguchi
T., Ichihara T., Imai K., Ishihara M., Jinnouchi O.,
Kajihara F., Kamihara N., Kaneta M., Kiyomichi A.,
Kurita K., Murata J., Onishi H., Okada H., Okada K.,
Rykov V. L., Saito N., Sato H., Shibata T., Shoji K.,
Tabaru T., Taketani A., Tanida K., Togawa M., TojoJ., Torii H., Tsuchimoto Y., Wagner M. M., WatanabeY., Xie W., and Yokkaichi S.: “Source breakup dynam√
ics in Au+Au Collisions at sNN =200 GeV via threedimensional two-pion source imaging”, Phys. Rev. Lett.
100, 232301-1–232301-6 (2008).
Afanasiev S., Akiba Y., Aoki K., Bunce G. M., DeshpandeA., Enyo H., Fields D. E., Fukao Y., Goto Y., Gross P.
M., Hachiya T., Hasuko K., Heuser J. M., Horaguchi
T., Ichihara T., Imai K., Ishihara M., Jinnouchi O.,
Kajihara F., Kamihara N., Kaneta M., Kiyomichi A.,
Kurita K., Murata J., Onishi H., Okada H., Okada K.,
Rykov V. L., Saito N., Sato H., Shibata T., Shoji K.,
Tabaru T., Taketani A., Tanida K., Togawa M., Tojo J.,
Torii H., Tsuchimoto Y., Wagner M. M., Watanabe Y.,
Xie W., and Yokkaichi S.: “Particle-species dependent
modiﬁcation of jet-induced correlations in Au+Au col√lisions at sNN = 200 GeV”, Phys. Rev. Lett. 101,
082301-1–082301-6 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K., Fukao
Y., Goto Y., Gross P. M., Horaguchi T., Ichihara T.,
Imai K., Inoue Y., Ishihara M., Jinnouchi O., KamiharaN., Kaneta M., Kanoh H., Kawall D., Kiyomichi A.,
Kurita K., Mao Y., Murata J., Nakagawa I., Nakano
K., Onishi H., Okada H., Okada K., Rykov V. L.,
Saito N., Shibata T., Shoji K., Tabaru T., Taketani A.,
Tanida K., Togawa M., Tojo J., Torii H., Wagner M.
M., Watanabe Y., Xie W., and Yokkaichi S.: “J/ψ Pro√
duction in sNN = 200 GeV Cu+Cu Collisions”, Phys.
Rev. Lett. 101, 122301-1–122301-6 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Dairaku S., Deshpande A., Enyo H., Fields D. E.,
Fujiwara K., Fukao Y., Goto Y., Gross P. M., Horaguchi
T., Ichihara T., Ichimiya R., Imai K., Inoue Y., Ishihara
M., Jinnouchi O., Kametani S., Kamihara N., Kaneta
M., Kanoh H., Kawall D., Kiyomichi A., Kurita K.,
Kurosawa M., Li Z., Mao Y., Murata J., Nakagawa I.,- 431 -

1

Nakano K., Onishi H., Okada H., Okada K., Onuki Y.,
Rykov V. L., Saito N., Sakashita K., Shibata T., Shoji
K., Tabaru T., Taketani A., Tanida K., Togawa M.,
Tojo J., Torii H., Wagner M. M., Watanabe Y., Xie W.,
and Yokkaichi S.: “Onset of π 0 suppression studied in√
Cu+Cu collisions at sNN = 22.4, 62.4, and 200 GeV”,
Phys. Rev. Lett. 101, 162301-1–162301-6 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K.,
Fukao Y., Goto Y., Gross P. M., Hachiya T., Hasuko K.,
Heuser J. M., Horaguchi T., Ichihara T., Imai K., Inoue
Y., Ishihara M., Jinnouchi O., Kajihara F., KamiharaN., Kaneta M., Kanoh H., Kawall D., Kiyomichi A.,
Kurita K., Mao Y., Murata J., Nakagawa I., Nakano K.,
Onishi H., Okada H., Okada K., Rykov V. L., Saito N.,
Sato H., Shibata T., Shoji K., Tabaru T., Taketani A.,
Tanida K., Togawa M., Tojo J., Torii H., Tsuchimoto Y.,
Wagner M. M., Watanabe Y., Xie W., and Yokkaichi S.:“Suppression pattern of neutral pions at high transverse√
momentum in Au+Au collisions at sNN = 200 GeV
and constraints on medium transport coeﬃcients”, Phys.
Rev. Lett. 101, 232301-1–232301-7 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K., Fukao
Y., Goto Y., Gross P. M., Horaguchi T., Ichihara T.,
Imai K., Inoue Y., Ishihara M., Jinnouchi O., KamiharaN., Kaneta M., Kanoh H., Kawall D., Kiyomichi A.,
Kurita K., Mao Y., Murata J., Nakagawa I., Nakano K.,
Onishi H., Okada H., Okada K., Rykov V. L., Saito N.,
Shibata T., Shoji K., Tabaru T., Taketani A., Tanida K.,
Togawa M., Tojo J., Torii H., Wagner M. M., WatanabeY., Xie W., and Yokkaichi S.: “Dilepton mass spectra√in p+p collisions at s = 200 GeV and the contribution
from open charm”, Phys. Lett. B 670, 313–320 (2009).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Dairaku S., Deshpande A., Enyo H., Fields D. E.,
Fujiwara K., Fukao Y., Goto Y., Gross P. M., Horaguchi
T., Ichihara T., Ichimiya R., Imai K., Ishihara M.,
Kametani S., Kamihara N., Kawall D., Kurita K.,
Kurosawa M., Li Z., Mao Y., Murata J., Nakagawa I.,
Nakano K., Okada H., Okada K., Onuki Y., Rykov V. L.,
Saito N., Sakashita K., Shibata T., Shoji K., Taketani
A., Tanida K., Togawa M., Torii H., Watanabe Y., Xie
W., and Yokkaichi S.: “Inclusive cross section and double helicity asymmetry for π 0 production in p + p colli√
sions at s = 62.4 GeV”, Phys. Rev. D 79, 012003-1–
012003-11 (2009).

- 432 -

2

RNCTheory Group

Publications
Publications[Journal](Original Papers) *Subject to Peer Review
Cheng M., Christ N. H., Jung C., Karsch F., Mawhinney
R. D., Petreczky P., and Petrov K.: “Flavor symmetry
breaking and scaling for improved staggered actions inquenched QCD”, Eur. Phys. J. C 51, No. 4, pp. 875–
881 (2007).
Cheng M., Christ N., Clark M. A., van der HeideJ., Jung C., Karsch F., Kaczmarek O., Laermann E.,
Mawhinney R. D., Miao C., Petreczky P., Petrov K.,
Schmidt C., Soeldner W., and Umeda T.: “Study of the
ﬁnite temperature transition in 3-ﬂavor QCD”, Phys.
Rev. D 75, No. 3, pp. 034506-1–034506-11 (2007).
Mocsy A. and Petreczky P.: “Quarkonium-signal of deconﬁnement”, J. Phys. G 35, No. 4, pp. 044038-1–044038-6(2008).
Datta S. and Petreczky P.: “Zero mode contribution inquarkonium correlators and in-medium properties ofheavy quarks”, J. Phys. G 35, No. 10, pp. 104114-1–104114-4 (2008).
Mocsy A. and Petreczky P.: “Quarkonium melting above
deconﬁnement”, J. Phys. G 35, No. 10, pp. 104154-1–
104154-4 (2008).
Hatsuda T., Aoki S., Ishii N., and Nemura H.: “From Lattice QCD to Nuclear Force”, Mod. Phys. Lett. A 23,
2265–2272 (2008).
Nemura H., Ishii N., Aoki S., and Hatsuda T.: “Lattice
QCD Simulation of Hyperon-Nucleon Potential”, Mod.
Phys. Lett. A 23, 2285–2288 (2008).
Cheng M., Christ N. H., Datta S., vander HeideJ., Jung C., Karsch F., Kaczmarek O., Laermann E.,
Mawhinney R. D., Miao C., Petreczky P., Petrov K.,
Schmidt C., Soeldner W., and Umeda T.: “QCD equation of state with almost physical quark masses”, Phys.
Rev. D 77, No. 1, pp. 014511-1–014511-20 (2008).
Brambilla N., Ghiglieri J., Vairo A., and Petreczky P.:“Static quark-antiquark pairs at ﬁnite temperature”,
Phys. Rev. D 78, No. 1, pp. 014017-1–014017-21(2008).
Bazavov A., Petreczky P., and Velytsky A.: “Static quarkantiquark pair in SU(2) gauge theory”, Phys. Rev. D
78, No. 11, pp. 114026-1–114026-12 (2008).
Aoki S., Balog J., Hatsuda T., Ishii N., Murano K.,
Nemura H., and Weisz P.: “Energy Dependence of
Nucleon-Nucleon Potentials”, Proceedings of Science
LATTICE 2008, No. 152, pp. 1–7 (2008).
Nemura H., Ishii N., Aoki S., and Hatsuda T.: “Lambdanucleon force from lattice QCD”, Proceedings of Science
LATTICE 2008, No. 156, pp. 1–7 (2008).
Petreczky P.: “On the temperature dependence of quarkonium correlators”, Eur. Phys. J. C, pp. 1–9 (2009).
Aoki Y., Borsanyi S., Durr S., Fodor Z., Katz S. D., Szabo

K. K., and Krieg S.: “The QCD transition temperature:
results with physical masses in the continuum limit II”,
J. High Energy Phys. 0906, 088-0–088-17 (2009).
Dumitru A.: “Quarkonium in a viscous QGP”, Nucl.
Phys. A 830, 323c–326c (2009).
Aoki Y., Borsanyi S., Durr S., Fodor Z., Katz S. D., Krieg
S., and Szabo K. K.: “QCD transition temperature: Approaching the continuum on the lattice”, Nucl. Phys. A
830, 805c–808c (2009).
Nemura H., Ishii N., Aoki S., and Hatsuda T.: “Hyperonnucleon force from lattice QCD”, Phys. Lett. B 673,
136–141 (2009).
Schenke B., Strickland M., Dumitru A., Nara Y.,
and Greiner C.: “Transverse momentum diﬀusion andcollisional jet energy loss in non-Abelian plasmas”, Phys.
Rev. C 79, 034903-1–034903-10 (2009).
Dumitru A., Guo Y., Mocsy A., and Strickland M.:“Quarkonium states in an anisotropic QCD plasma”,
Phys. Rev. D 79, 054019-1–054019-10 (2009).
Dumitru A., Guo Y., and Strickland M.: “Imaginary partof the static gluon propagator in an anisotropic (viscous)
QCD plasma”, Phys. Rev. D 79, 114003-1–114003-7(2009).
Yamazaki T., Aoki Y., Blum T., Lin H., Ohta S., Sasaki S.,
Tweedie R. J., and Zanotti J. M.: “Nucleon form factors
with 2+1 ﬂavor dynamical domain-wall fermions”, Phys.
Rev. D 79, 114505-1–114505-20 (2009).
Noronha J. and Dumitru A.: “Heavy quark potential asa function of shear viscosity at strong coupling”, Phys.
Rev. D 80, 014007-1–014007-8 (2009).
Sturm C., Aoki Y., Christ N. H., Izubuchi T., Sachrajda
C. T., and Soni A.: “Renormalization of quark bilinear operators in a momentum-subtraction scheme witha nonexceptional subtraction point”, Phys. Rev. D 80,
014501-1–014501-11 (2009).
Noronha J. and Dumitru A.: “Thermal Width of the Υat Large ’t Hooft Coupling”, Phys. Rev. Lett. 103,
152304-1–152304-4 (2009).
Ishikawa T., Aoki Y., and Izubuchi T.: “Improving chiral property of domain-wall fermions by reweighting
method”, Proceedings of Science LAT2009, No. 035,
pp. 1–7 (2010).
Ohta S.: “Nucleon structure functions from dynamical(2+1)-ﬂavor domain wall fermions”, Proceedings of Science LAT2009, No. 131, pp. 1–7 (2010).
(Review)
Petreczky P.: “Lattice QCD at ﬁnite temperature”, Nucl.
Phys. A 785, No. 1, pp. 10c–17c (2007).

Oral Presentations
Oral Presentations((International) Conference etc.)
Nemura H., Ishii N., Aoki S., and Hatsuda T.: “Lambdanucleon force from lattice QCD”, Lattice 2008, 26th International Symposium on Lattice Field Theory, (College of Williams and Mary), Virginia, USA, July (2008).

- 433 -

1

Nemura H., Ishii N., Aoki S., and Hatsuda T.: “Hyperonnucleon force calculated from lattice QCD”, KGU Yokohama Autumn School of Nuclear Physics, (KGU), Yokohama, Oct. (2008).
Nemura H., Ishii N., Aoki S., and Hatsuda T.: “Studyof hyperon-nucleon potential from lattice QCD”, Sendai
International Symposium on Strangeness in Nuclear andHadronic Systems (SENDAI08), (Tohoku University),
Sendai, Dec. (2008).
Dumitru A.: “Quarkonium states in an anisotropic (viscous) QGP”, 21st International Conference on Ultrarelativistic Nucleus-Nucleus Collisions (Quark Matter 2009),
Knoxville, USA, Mar.–Apr. (2009).
Aoki Y.: “BNL Non-perturbative renormalization”, 27th
International Symposium on Lattice Field Theory (Lattice 2009), Beijing, China, July (2009).
Ishikawa T.: “Improving chiral property of domain-wall
fermions by reweighting method”, 27th International
Symposium on Lattice Field Theory (Lattice 2009),(University of Beijing), Beijing, China, July (2009).
Aoki Y.: “Hadronic matrix elements of proton decay fromlattice QCD”, 2009 Workshop on Lepton and Baryon
Number Violation (LBV09), (University of WisconsinMadison), Madison, USA, Sept. (2009).
Aoki Y.: “Nucleon properties from chirally symmetric lattice QCD”, 3rd Joint Meeting of the Nuclear Physics
Divisions of the APS and JPS (Hawaii 2009), Hawaii,
USA, Oct. (2009).
Aoki Y.: “Lattice QCD Perspective”, RBRC Symposium,
Upton, USA, Dec. (2009).
Dumitru A.: “Snapshot of the Glasma from RHIC: theRidge”, RBRC Symposium, Upton, USA, Dec. (2009).
((Domestic )Conference)
,
,
,
: “
QCD
”,
- ,(
),
, 8 (2008).
,
,
,
: “
QCD
”,

A02
,
,

: “
, 12

QCD
(2009).

,3”,(2009).
QCD

2008,, 10 (2008).
,,,: “Hyperon Potentials from Lattice QCD”, Aizu meeting 2009 on Spin
Excitations and Exotic Degree of Freedom in Nuclei and
Nuclear Matter,,2(2009).
,
,
,
: “
QCD
”,

,
,

,

ΛN
),
,

,2
,

”,
, 3 (2009).
,,”,(2009).
: “
64

QCD

: “

QCD

,(

- 434 -

2

Experimental Group
RNC
Publications
Publications[]
Journal(Original Papers) *Subject to Peer Review
Adare A., Akiba Y., Aoki K., Asai J., Bazilevsky A. V.,
Bunce G. M., Deshpande A., Enyo H., Fields D. E.,
Fox B., Fujiwara K., Fukao Y., Goto Y., Gross P. M.,
Hasuko K., Heuser J. M., Horaguchi T., Ichihara T.,
Imai K., Inoue Y., Ishihara M., Jinnouchi O., KamiharaN., Kaneta M., Kanoh H., Kawall D., Kiyomichi A.,
Kobayashi H., Kurita K., Mao Y., Murata J., Nakagawa
I., Nakano K., Onishi H., Okada H., Okada K., Rykov V.
L., Saito N., Sato H., Shibata T., Shoji K., Tabaru T.,
Taketani A., Tanida K., Togawa M., Tojo J., Torii H.,
Wagner M. M., Watanabe Y., Xie W., and Yokkaichi
S.: “Cold Nuclear Matter Eﬀects on J/ψ Production as Constrained by Deuteron-Gold Measurements at√
sNN = 200 GeV”, Phys. Rev. C 77, 024912-1–02491215 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K., Fukao
Y., Goto Y., Gross P. M., Hachiya T., Hasuko K., Heuser
J. M., Horaguchi T., Ichihara T., Imai K., Inoue Y.,
Ishihara M., Jinnouchi O., Kajihara F., Kamihara N.,
Kaneta M., Kanoh H., Kawall D., Kiyomichi A., Kurita
K., Mao Y., Murata J., Nakagawa I., Nakano K., Onishi
H., Okada H., Okada K., Rykov V. L., Saito N., Sato H.,
Shibata T., Shoji K., Tabaru T., Taketani A., Tanida K.,
Togawa M., Tojo J., Torii H., Tsuchimoto Y., Wagner
M. M., Watanabe Y., Xie W., and Yokkaichi S.: “Quantitative Constraints on the Transport Properties of Hot
Partonic Matter from Semi-Inclusive Single High Transverse Momentum Pion Suppression in Au+Au Collisions√
at sNN = 200 GeV”, Phys. Rev. C 77, 064907-1–
064907-12 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K., Fukao
Y., Goto Y., Gross P. M., Hachiya T., Hasuko K., Heuser
J. M., Horaguchi T., Ichihara T., Imai K., Inoue Y.,
Ishihara M., Jinnouchi O., Kajihara F., Kamihara N.,
Kaneta M., Kanoh H., Kawall D., Kiyomichi A., Kurita
K., Mao Y., Murata J., Nakagawa I., Nakano K., Onishi
H., Okada H., Okada K., Rykov V. L., Saito N., Sato H.,
Shibata T., Shoji K., Tabaru T., Taketani A., Tanida K.,
Togawa M., Tojo J., Torii H., Tsuchimoto Y., Wagner
M. M., Watanabe Y., Xie W., and Yokkaichi S.: “Dihadron azimuthal correlations in Au+Au collisions at√
sNN = 200 GeV”, Phys. Rev. C 78, 014901-1–01490142 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bazilevsky A. V.,
Bunce G. M., Deshpande A., Enyo H., Fields D. E.,
Fox B., Fujiwara K., Fukao Y., Goto Y., Gross P. M.,
Hachiya T., Hasuko K., Heuser J. M., Horaguchi T.,
Ichihara T., Imai K., Inoue Y., Ishihara M., Jinnouchi

O., Kajihara F., Kamihara N., Kaneta M., Kanoh H.,
Kawall D., Kiyomichi A., Kobayashi H., Kurita K., Mao
Y., Murata J., Nakagawa I., Nakano K., Onishi H.,
Okada H., Okada K., Rykov V. L., Saito N., Sato H.,
Shibata T., Shoji K., Tabaru T., Taketani A., Tanida
K., Togawa M., Tojo J., Torii H., Tsuchimoto Y.,
Wagner M. M., Watanabe Y., Xie W., and Yokkaichi
S.: “Charged hadron multiplicity ﬂuctuations in Au+Au√
and Cu+Cu collisions from sNN = 22.5 to 200 GeV”,
Phys. Rev. C 78, 044902-1–044902-15 (2008).
Afanasiev S., Akiba Y., Aoki K., Bunce G. M., DeshpandeA., Enyo H., Fields D. E., Fukao Y., Goto Y., Gross P.
M., Hachiya T., Hasuko K., Heuser J. M., Horaguchi
T., Ichihara T., Imai K., Ishihara M., Jinnouchi O.,
Kajihara F., Kamihara N., Kaneta M., Kiyomichi A.,
Kurita K., Murata J., Onishi H., Okada H., Okada K.,
Rykov V. L., Saito N., Sato H., Shibata T., Shoji K.,
Tabaru T., Taketani A., Tanida K., Togawa M., TojoJ., Torii H., Tsuchimoto Y., Wagner M. M., WatanabeY., Xie W., and Yokkaichi S.: “Source breakup dynam√
ics in Au+Au Collisions at sNN =200 GeV via threedimensional two-pion source imaging”, Phys. Rev. Lett.
100, 232301-1–232301-6 (2008).
Afanasiev S., Akiba Y., Aoki K., Bunce G. M., DeshpandeA., Enyo H., Fields D. E., Fukao Y., Goto Y., Gross P.
M., Hachiya T., Hasuko K., Heuser J. M., Horaguchi
T., Ichihara T., Imai K., Ishihara M., Jinnouchi O.,
Kajihara F., Kamihara N., Kaneta M., Kiyomichi A.,
Kurita K., Murata J., Onishi H., Okada H., Okada K.,
Rykov V. L., Saito N., Sato H., Shibata T., Shoji K.,
Tabaru T., Taketani A., Tanida K., Togawa M., Tojo J.,
Torii H., Tsuchimoto Y., Wagner M. M., Watanabe Y.,
Xie W., and Yokkaichi S.: “Particle-species dependent
modiﬁcation of jet-induced correlations in Au+Au col√lisions at sNN = 200 GeV”, Phys. Rev. Lett. 101,
082301-1–082301-6 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K., Fukao
Y., Goto Y., Gross P. M., Horaguchi T., Ichihara T.,
Imai K., Inoue Y., Ishihara M., Jinnouchi O., KamiharaN., Kaneta M., Kanoh H., Kawall D., Kiyomichi A.,
Kurita K., Mao Y., Murata J., Nakagawa I., Nakano
K., Onishi H., Okada H., Okada K., Rykov V. L.,
Saito N., Shibata T., Shoji K., Tabaru T., Taketani A.,
Tanida K., Togawa M., Tojo J., Torii H., Wagner M.
M., Watanabe Y., Xie W., and Yokkaichi S.: “J/ψ Pro√
duction in sNN = 200 GeV Cu+Cu Collisions”, Phys.
Rev. Lett. 101, 122301-1–122301-6 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Dairaku S., Deshpande A., Enyo H., Fields D. E.,
Fujiwara K., Fukao Y., Goto Y., Gross P. M., Horaguchi
T., Ichihara T., Ichimiya R., Imai K., Inoue Y., Ishihara
M., Jinnouchi O., Kametani S., Kamihara N., Kaneta
M., Kanoh H., Kawall D., Kiyomichi A., Kurita K.,
Kurosawa M., Li Z., Mao Y., Murata J., Nakagawa I.,- 435 -

1

Nakano K., Onishi H., Okada H., Okada K., Onuki Y.,
Rykov V. L., Saito N., Sakashita K., Shibata T., Shoji
K., Tabaru T., Taketani A., Tanida K., Togawa M.,
Tojo J., Torii H., Wagner M. M., Watanabe Y., Xie W.,
and Yokkaichi S.: “Onset of π 0 suppression studied in√
Cu+Cu collisions at sNN = 22.4, 62.4, and 200 GeV”,
Phys. Rev. Lett. 101, 162301-1–162301-6 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K.,
Fukao Y., Goto Y., Gross P. M., Hachiya T., Hasuko K.,
Heuser J. M., Horaguchi T., Ichihara T., Imai K., Inoue
Y., Ishihara M., Jinnouchi O., Kajihara F., KamiharaN., Kaneta M., Kanoh H., Kawall D., Kiyomichi A.,
Kurita K., Mao Y., Murata J., Nakagawa I., Nakano K.,
Onishi H., Okada H., Okada K., Rykov V. L., Saito N.,
Sato H., Shibata T., Shoji K., Tabaru T., Taketani A.,
Tanida K., Togawa M., Tojo J., Torii H., Tsuchimoto Y.,
Wagner M. M., Watanabe Y., Xie W., and Yokkaichi S.:“Suppression pattern of neutral pions at high transverse√
momentum in Au+Au collisions at sNN = 200 GeV
and constraints on medium transport coeﬃcients”, Phys.
Rev. Lett. 101, 232301-1–232301-7 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K., Fukao
Y., Goto Y., Gross P. M., Horaguchi T., Ichihara T.,
Imai K., Inoue Y., Ishihara M., Jinnouchi O., KamiharaN., Kaneta M., Kanoh H., Kawall D., Kiyomichi A.,
Kurita K., Mao Y., Murata J., Nakagawa I., Nakano K.,
Onishi H., Okada H., Okada K., Rykov V. L., Saito N.,
Shibata T., Shoji K., Tabaru T., Taketani A., Tanida K.,
Togawa M., Tojo J., Torii H., Wagner M. M., WatanabeY., Xie W., and Yokkaichi S.: “Dilepton mass spectra√in p+p collisions at s = 200 GeV and the contribution
from open charm”, Phys. Lett. B 670, 313–320 (2009).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Dairaku S., Deshpande A., Enyo H., Fields D. E.,
Fujiwara K., Fukao Y., Goto Y., Gross P. M., Horaguchi
T., Ichihara T., Ichimiya R., Imai K., Ishihara M.,
Kametani S., Kamihara N., Kawall D., Kurita K.,
Kurosawa M., Li Z., Mao Y., Murata J., Nakagawa I.,
Nakano K., Okada H., Okada K., Onuki Y., Rykov V. L.,
Saito N., Sakashita K., Shibata T., Shoji K., Taketani
A., Tanida K., Togawa M., Torii H., Watanabe Y., Xie
W., and Yokkaichi S.: “Inclusive cross section and double helicity asymmetry for π 0 production in p + p colli√
sions at s = 62.4 GeV”, Phys. Rev. D 79, 012003-1–
012003-11 (2009).

- 436 -

2

RIKEN
Facility Office at RAL
RNC
Publications
Publications[Journal](Original Papers) *Subject to Peer Review
Imao H., Ishida K., Kawamura N., Matsuzaki T., Matsuda
Y., Toyoda A., Strasser P., Iwasaki M., and NagamineK.: “Density eﬀect in d-d muon-catalyzed fusion withortho- and para-enriched deuterium”, Hyperﬁne Interact. 193, No. 1-3, pp. 159–163 (2009).

Oral Presentations
Oral Presentations((International) Conference etc.)
Matsuzaki T.: “Developments of Extreme ConditionedµSR setups”, RIKEN Symposium on Molecular Ensemble 2009, Wako, Dec. (2009).
((Domestic)Conference),,: “µSR-µSR”,59,, 9 (2009).
: “
D2
”,
-RAL
2009 , (J-PARC/MLF),, 1 (2010).
: “
-RAL
”,
-RAL
2009 , (J-PARC/MLF),, 1 (2010).

- 437 -

1

HeavyIon Nuclear Physics Laboratory
RNC
Publications
Publications[Journal](Original Papers) *Subject to Peer Review
Tatsumi K., Mitani Y., Watanabe J., Takakura H., Hoshi
K., Kawai Y., Kikuchi T., Kougo Y., Katayama A.,
Tomaru Y., Kanamori H., Usui K., Itoh M., Cizdziel
P. E., Lejava A., Ueda M., Ichikawa Y., Endo I., Togo
S., Shimada H., and Hayashizaki Y.: “Rapid screening
assay for KRAS mutations by the modiﬁed SMart Ampliﬁcation Process”, J. Mol. Diagn. 10, No. 6, pp.
520–526 (2008).
Ohnishi T., Kubo T., Kusaka K., Yoshida A., YoshidaK., Fukuda N., Ohtake M., Yanagisawa Y., Takeda H.,
Kameda D., Yamaguchi Y., Aoi N., Yoneda K., Otsu H.,
Takeuchi S., Sugimoto T., Kondo Y., Scheit H., Gono
Y., Sakurai H., Motobayashi T., Suzuki H., Nakao T.,
Kimura H., Mizoi Y., Matsushita M., Ieki K., Kuboki
T., Yamaguchi T., Suzuki T., Ozawa A., Moriguchi T.,
Yasuda Y., Nakamura T., Nannichi T., Shimamura T.,
Nakayama Y., Geissel H., Weick H., Nolen J. A., Tarasov
O. B., Nettleton A. S., Bazin D. P., Sherrill B. M.,
Morrissey D. J., and Mittig W.: “Identiﬁcation of New
Isotopes 125 Pd and 126 Pd Produced by In-Flight Fission of 345 MeV/nucleon 238 U: First Results from the
RIKEN RI Beam Factory”, J. Phys. Soc. Jpn. 77, No.
8, pp. 083201-1–083201-4 (2008).
Moriwaki Y., Matsuo Y., Fukuyama Y., and Morita N.:“Fine structure changing cross section of Ba+ ions incollisions with He atoms”, Jpn. J. Appl. Phys. 47,
1757–1759 (2008).
Nakajima T., Matsuo Y., and Kobayashi T.: “All-opticalcontrol and direct detection of ultrafast spin polarization
in a multi-valence-electron system”, Phys. Rev. A 77,
063404-1–063404-4 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bazilevsky A. V.,
Bunce G. M., Deshpande A., Enyo H., Fields D. E.,
Fox B., Fujiwara K., Fukao Y., Goto Y., Gross P. M.,
Hasuko K., Heuser J. M., Horaguchi T., Ichihara T.,
Imai K., Inoue Y., Ishihara M., Jinnouchi O., KamiharaN., Kaneta M., Kanoh H., Kawall D., Kiyomichi A.,
Kobayashi H., Kurita K., Mao Y., Murata J., Nakagawa
I., Nakano K., Onishi H., Okada H., Okada K., Rykov V.
L., Saito N., Sato H., Shibata T., Shoji K., Tabaru T.,
Taketani A., Tanida K., Togawa M., Tojo J., Torii H.,
Wagner M. M., Watanabe Y., Xie W., and Yokkaichi
S.: “Cold Nuclear Matter Eﬀects on J/ψ Production as Constrained by Deuteron-Gold Measurements at√
sNN = 200 GeV”, Phys. Rev. C 77, 024912-1–02491215 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K., Fukao
Y., Goto Y., Gross P. M., Hachiya T., Hasuko K., Heuser
J. M., Horaguchi T., Ichihara T., Imai K., Inoue Y.,

Ishihara M., Jinnouchi O., Kajihara F., Kamihara N.,
Kaneta M., Kanoh H., Kawall D., Kiyomichi A., Kurita
K., Mao Y., Murata J., Nakagawa I., Nakano K., Onishi
H., Okada H., Okada K., Rykov V. L., Saito N., Sato H.,
Shibata T., Shoji K., Tabaru T., Taketani A., Tanida K.,
Togawa M., Tojo J., Torii H., Tsuchimoto Y., Wagner
M. M., Watanabe Y., Xie W., and Yokkaichi S.: “Quantitative Constraints on the Transport Properties of Hot
Partonic Matter from Semi-Inclusive Single High Transverse Momentum Pion Suppression in Au+Au Collisions√
at sNN = 200 GeV”, Phys. Rev. C 77, 064907-1–
064907-12 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K., Fukao
Y., Goto Y., Gross P. M., Hachiya T., Hasuko K., Heuser
J. M., Horaguchi T., Ichihara T., Imai K., Inoue Y.,
Ishihara M., Jinnouchi O., Kajihara F., Kamihara N.,
Kaneta M., Kanoh H., Kawall D., Kiyomichi A., Kurita
K., Mao Y., Murata J., Nakagawa I., Nakano K., Onishi
H., Okada H., Okada K., Rykov V. L., Saito N., Sato H.,
Shibata T., Shoji K., Tabaru T., Taketani A., Tanida K.,
Togawa M., Tojo J., Torii H., Tsuchimoto Y., Wagner
M. M., Watanabe Y., Xie W., and Yokkaichi S.: “Dihadron azimuthal correlations in Au+Au collisions at√
sNN = 200 GeV”, Phys. Rev. C 78, 014901-1–01490142 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bazilevsky A. V.,
Bunce G. M., Deshpande A., Enyo H., Fields D. E.,
Fox B., Fujiwara K., Fukao Y., Goto Y., Gross P. M.,
Hachiya T., Hasuko K., Heuser J. M., Horaguchi T.,
Ichihara T., Imai K., Inoue Y., Ishihara M., Jinnouchi
O., Kajihara F., Kamihara N., Kaneta M., Kanoh H.,
Kawall D., Kiyomichi A., Kobayashi H., Kurita K., Mao
Y., Murata J., Nakagawa I., Nakano K., Onishi H.,
Okada H., Okada K., Rykov V. L., Saito N., Sato H.,
Shibata T., Shoji K., Tabaru T., Taketani A., Tanida
K., Togawa M., Tojo J., Torii H., Tsuchimoto Y.,
Wagner M. M., Watanabe Y., Xie W., and Yokkaichi
S.: “Charged hadron multiplicity ﬂuctuations in Au+Au√
and Cu+Cu collisions from sNN = 22.5 to 200 GeV”,
Phys. Rev. C 78, 044902-1–044902-15 (2008).
Afanasiev S., Akiba Y., Aoki K., Bunce G. M., DeshpandeA., Enyo H., Fields D. E., Fukao Y., Goto Y., Gross P.
M., Hachiya T., Hasuko K., Heuser J. M., Horaguchi
T., Ichihara T., Imai K., Ishihara M., Jinnouchi O.,
Kajihara F., Kamihara N., Kaneta M., Kiyomichi A.,
Kurita K., Murata J., Onishi H., Okada H., Okada K.,
Rykov V. L., Saito N., Sato H., Shibata T., Shoji K.,
Tabaru T., Taketani A., Tanida K., Togawa M., TojoJ., Torii H., Tsuchimoto Y., Wagner M. M., WatanabeY., Xie W., and Yokkaichi S.: “Source breakup dynam√
ics in Au+Au Collisions at sNN =200 GeV via threedimensional two-pion source imaging”, Phys. Rev. Lett.
100, 232301-1–232301-6 (2008).
Afanasiev S., Akiba Y., Aoki K., Bunce G. M., Deshpande- 438 -

1

A., Enyo H., Fields D. E., Fukao Y., Goto Y., Gross P.
M., Hachiya T., Hasuko K., Heuser J. M., Horaguchi
T., Ichihara T., Imai K., Ishihara M., Jinnouchi O.,
Kajihara F., Kamihara N., Kaneta M., Kiyomichi A.,
Kurita K., Murata J., Onishi H., Okada H., Okada K.,
Rykov V. L., Saito N., Sato H., Shibata T., Shoji K.,
Tabaru T., Taketani A., Tanida K., Togawa M., Tojo J.,
Torii H., Tsuchimoto Y., Wagner M. M., Watanabe Y.,
Xie W., and Yokkaichi S.: “Particle-species dependent
modiﬁcation of jet-induced correlations in Au+Au col√lisions at sNN = 200 GeV”, Phys. Rev. Lett. 101,
082301-1–082301-6 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K., Fukao
Y., Goto Y., Gross P. M., Horaguchi T., Ichihara T.,
Imai K., Inoue Y., Ishihara M., Jinnouchi O., KamiharaN., Kaneta M., Kanoh H., Kawall D., Kiyomichi A.,
Kurita K., Mao Y., Murata J., Nakagawa I., Nakano
K., Onishi H., Okada H., Okada K., Rykov V. L.,
Saito N., Shibata T., Shoji K., Tabaru T., Taketani A.,
Tanida K., Togawa M., Tojo J., Torii H., Wagner M.
M., Watanabe Y., Xie W., and Yokkaichi S.: “J/ψ Pro√
duction in sNN = 200 GeV Cu+Cu Collisions”, Phys.
Rev. Lett. 101, 122301-1–122301-6 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Dairaku S., Deshpande A., Enyo H., Fields D. E.,
Fujiwara K., Fukao Y., Goto Y., Gross P. M., Horaguchi
T., Ichihara T., Ichimiya R., Imai K., Inoue Y., Ishihara
M., Jinnouchi O., Kametani S., Kamihara N., Kaneta
M., Kanoh H., Kawall D., Kiyomichi A., Kurita K.,
Kurosawa M., Li Z., Mao Y., Murata J., Nakagawa I.,
Nakano K., Onishi H., Okada H., Okada K., Onuki Y.,
Rykov V. L., Saito N., Sakashita K., Shibata T., Shoji
K., Tabaru T., Taketani A., Tanida K., Togawa M.,
Tojo J., Torii H., Wagner M. M., Watanabe Y., Xie W.,
and Yokkaichi S.: “Onset of π 0 suppression studied in√
Cu+Cu collisions at sNN = 22.4, 62.4, and 200 GeV”,
Phys. Rev. Lett. 101, 162301-1–162301-6 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K.,
Fukao Y., Goto Y., Gross P. M., Hachiya T., Hasuko K.,
Heuser J. M., Horaguchi T., Ichihara T., Imai K., Inoue
Y., Ishihara M., Jinnouchi O., Kajihara F., KamiharaN., Kaneta M., Kanoh H., Kawall D., Kiyomichi A.,
Kurita K., Mao Y., Murata J., Nakagawa I., Nakano K.,
Onishi H., Okada H., Okada K., Rykov V. L., Saito N.,
Sato H., Shibata T., Shoji K., Tabaru T., Taketani A.,
Tanida K., Togawa M., Tojo J., Torii H., Tsuchimoto Y.,
Wagner M. M., Watanabe Y., Xie W., and Yokkaichi S.:“Suppression pattern of neutral pions at high transverse√
momentum in Au+Au collisions at sNN = 200 GeV
and constraints on medium transport coeﬃcients”, Phys.
Rev. Lett. 101, 232301-1–232301-7 (2008).
Dang N. D. and Nguyen H. Q.: “Nuclear pairing at ﬁnite
temperature and angular momentum”, AIP Conf. Proc.

1090, 179–183 (2009).
Nakajima T., Matsuo Y., and Kobayashi T.: “First step
toward ultrafast nuclear-spin polarization: All-opticalcontrol and direct detection of ultrafast electron-spin
polarization using femtosecond laser pulses”, AIP Conf.
Proc. 1149, 876–879 (2009).
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., Fukuda N.,
Kubono S., Motobayashi T., Nakabayashi T., Nakao T.,
Okumura T., Ong H., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Investigation into behavior of weakly-bound proton via
B(GT) measurement for the β decay of 24 Si”, AIP Conf.
Proc. 1165, 98–101 (2009).
Kobayashi T., Matsuo Y., Nishimura M., Hayashizaki Y.,
and Kawai J.: “Hydrogenation of carbon fragments after
femtosecond laser ablation of solid C60 ”, Appl. Surf. Sci.
255, 9652–9654 (2009).
Nishimura M., Kobayashi T., Matsuo Y., Motobayashi T.,
Hayashizaki Y., and Kawai J.: “Dynamics of Ablation
Plasma induced by a Femtosecond Laser Pulse in Electric Fields”, Appl. Surf. Sci. 255, 9729–9733 (2009).
Ichikawa Y., Kubo T., Aoi N., Naik V., ChakrabartiA., Fukuda N., Iwasaki H., Kubono S., Motobayashi
T., Nakabayashi T., Nakao T., Okumura T., Ong H.,
Onishi T., Suzuki D., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Betadecay study of Tz = −2 proton-rich nucleus 24 Si”, Eur.
Phys. J. A 42, 375–378 (2009).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K., Fukao
Y., Goto Y., Gross P. M., Horaguchi T., Ichihara T.,
Imai K., Inoue Y., Ishihara M., Jinnouchi O., KamiharaN., Kaneta M., Kanoh H., Kawall D., Kiyomichi A.,
Kurita K., Mao Y., Murata J., Nakagawa I., Nakano K.,
Onishi H., Okada H., Okada K., Rykov V. L., Saito N.,
Shibata T., Shoji K., Tabaru T., Taketani A., Tanida K.,
Togawa M., Tojo J., Torii H., Wagner M. M., WatanabeY., Xie W., and Yokkaichi S.: “Dilepton mass spectra√in p+p collisions at s = 200 GeV and the contribution
from open charm”, Phys. Lett. B 670, 313–320 (2009).
De Rydt M., Neyens G., Asahi K., Balabanski D. L.,
Daugas J., Depuydt M., Gaudefroy L., Grevy S.,
Hasama Y., Ichikawa Y., Morel P., Nagatomo T.,
Ohtsuka T., Perrot L., Shimada K., Stoedel C., ThomasJ., Ueno H., Utsuno Y., Wannes V., Vermeulen N.,
Vingerhoets P., and Yoshimi A.: “Precision measurement of the electric quadrupole moment of 31 Al anddetermination of the eﬀective proton charge in the sdshell”, Phys. Lett. B 678, 344–349 (2009).
Takeuchi S., Aoi N., Motobayashi T., Ota S., TakeshitaE., Suzuki H., Baba H., Fukui T., Hashimoto Y., Ieki
K., Imai N., Iwasaki H., Kanno S., Kondo Y., Kubo T.,- 439 -

2

Kurita K., Minemura T., Nakamura T., Okumura T.,
Onishi T., Sakurai H., Shimoura S., Sugou R., SuzukiD., Suzuki M., Takashina M., Tamaki M., Tanaka K.,
Togano Y., and Yamada K.: “Low-Iying States in 32Mg
studied by proton inelastic scattering”, Phys. Rev. C
79, No. 5, pp. 054319-1–054319-11 (2009).
Nguyen H. Q. and Dang N. D.: “Exact and Approximate
Ensemble Treatments of Thermal Pairing in a Multilevel
Model”, Phys. Rev. C 79, No. 5, pp. 054328-1–05432810 (2009).
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., Fukuda N.,
Kubono S., Motobayashi T., Nakabayashi T., Nakao T.,
Okumura T., Ong H., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Betadecay of the proton-rich nucleus 24 Si and its mirror
asymmetry”, Phys. Rev. C 80, 044302-1–044302-12(2009).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Dairaku S., Deshpande A., Enyo H., Fields D. E.,
Fujiwara K., Fukao Y., Goto Y., Gross P. M., Horaguchi
T., Ichihara T., Ichimiya R., Imai K., Ishihara M.,
Kametani S., Kamihara N., Kawall D., Kurita K.,
Kurosawa M., Li Z., Mao Y., Murata J., Nakagawa I.,
Nakano K., Okada H., Okada K., Onuki Y., Rykov V. L.,
Saito N., Sakashita K., Shibata T., Shoji K., Taketani
A., Tanida K., Togawa M., Torii H., Watanabe Y., Xie
W., and Yokkaichi S.: “Inclusive cross section and double helicity asymmetry for π 0 production in p + p colli√
sions at s = 62.4 GeV”, Phys. Rev. D 79, 012003-1–
012003-11 (2009).
(Others)
Murata J., Akiyama T., Hata M., Hirayama Y., Ikeda
Y., Ishii T., Kameda D., Kawamura H., Mitsuoka
S., Miyatake H., Nagae D., Ninomiya K., Nitta M.,
Seitaibashi E., and Toyoda T.: “Test of time reversal
symmetry using polarized nuclei”, JAEA-Review 2009036, 62–63 (2009).
[Book • Proceedings
Proc.](Others)
Fukunishi N., Fujimaki M., Watanabe T., Kumagai K.,
Komiyama M., Watanabe H., Goto A., Hasebe H.,
Higurashi Y., Ikezawa E., Kageyama T., Kamigaito
O., Kase M., Kuboki H., Kidera M., Nagase M., Maie
T., Nakagawa T., Ohnishi J., Okuno H., SakamotoN., Sekiguchi K., Suda K., Suzuki H., Wakasugi M.,
Watanabe Y., Yokouchi S., Yano Y., and Yamada K.:“Operating experience with the RIKEN Radioactive Isotope Beam Factory”, Proceedings of the 2009 Particle
Accelerator Conference (PAC09), Vancouver, Canada,
2009–5, PAC09 Editor, Vancouver, pp. MO3GRI0-1–
MO3GRI0-5 (2009).

Oral Presentations
Oral Presentations((International) Conference etc.)

Takeuchi S.: “Detector array for low intensity radiation”, CNS-RIKEN Joint Symposium on Frontier ofGamma-Ray Spectroscopy and Its Application, Wako,
Mar. (2004).
Takeuchi S., Shimoura S., Motobayashi T., Akiyoshi H.,
Ando Y., Aoi N., Fulop Z., Gomi T., Higurashi Y.,
Hirai M., Iwasa N., Iwasaki H., Iwata Y., Kobayashi H.,
Kurokawa M., Liu Z., Minemura T., Ozawa S., Sakurai
H., Serata M., Teranishi T., Yamada K., Yanagisawa
Y., and Ishihara M.: “Isobaric analog state of 14 Be”,
RIKEN-CNS RIBF International Workshop “Correlation and Condensation: New Features in Loosely Boundand Unbound Nuclear States”, Wako, Dec. (2005).
Ohnishi T., Kubo T., Kusaka K., Yoshida A., YoshidaK., Fukuda N., Yanagisawa Y., Ohtake M., Takeda
H., and Kameda D.: “BigRIPS Commissioning Experiment”, Third experts meeting on critical issues of nextgeneration high-intensity In-ﬂight separators, (National
Superconducting Cyclotron Laboratory, Michigan State
University), East Lansing, USA, Mar.–Apr. (2008).
Fukunishi N., Fujimaki M., Watanabe T., Kumagai K.,
Komiyama M., Watanabe H., Goto A., Hasebe H.,
Higurashi Y., Ikezawa E., Kageyama T., Kamigaito
O., Kase M., Kuboki H., Kidera M., Nagase M., Maie
T., Nakagawa T., Ohnishi J., Okuno H., SakamotoN., Sekiguchi K., Suda K., Suzuki H., Wakasugi M.,
Watanabe Y., Yokouchi S., Yano Y., and Yamada K.:“Operating experience with the RIKEN Radioactive Isotope Beam Factory”, 23rd Particle Accelerator Conference (PAC09), Vancouver, Canada, May (2009).
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., Fukuda N.,
Kubono S., Motobayashi T., Nakabayashi T., Nakao T.,
Okumura T., Ong H., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Investigation into behavior of weakly-bound proton via
B(GT) measurement for the β decay of 24 Si”, International Conference on Nuclear Structure and Dynamics(NSD09), (University of Zagreb), Dubrovnik, Croatia,
May (2009).
Furukawa T., Hatakeyama A., Fujikake K., Matsuura Y.,
Kobayashi T., Shimoda T., and Matsuo Y.: “Precision
Laser Spectroscopy of Alkaline and Alkaline-like Atoms
in Superﬂuid Helium”, 19th International Conferenceon Laser Spectroscopy (ICOLS2009), Kussharo, June(2009).
Matsuo Y.: “Novel nuclear laser spectroscopy of RI
atoms in superﬂuid helium: OROCHI”, Advanced Studies Institute: Symmetries and Spin (SPIN-Praha-2009),
Praha, Czech, July–Aug. (2009).
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., Fukuda N.,
Kubono S., Motobayashi T., Nakabayashi T., Nakao T.,
Okumura T., Ong H., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Beta- 440 -

3

decay of 24 Si and mirror asymmetry of Gamow-Tellertransition strength”, 3rd Joint Meeting of the Nuclear
Physics Divisions of the APS and JPS (Hawaii 2009),
Hawaii, USA, Oct. (2009).
Sasaki A., Wakui T., Furukawa T., Kazato M., Wada M.,
Sonoda T., Takamine A., Kobayashi T., Nishimura M.,
Ueno H., Yoshimi A., Aoi N., Nishimura S., Togano Y.,
Takechi M., Kondo Y., Hatakeyama A., Matsuura Y.,
Kato Y., Odahara A., Shimoda T., Asahi K., ShinozukaT., Motobayashi T., and Matsuo Y.: “Fluorescence detection system for nuclear laser spectroscopy of Rb in
superﬂuid helium”, 3rd Joint Meeting of the Nuclear
Physics Divisions of the APS and JPS (Hawaii 2009),
Hawaii, USA, Oct. (2009).
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., FukudaN., Kubono S., Motobayashi T., Nakabayashi T., Nakao
T., Okumura T., Ong H., Suzuki H., Suzuki M.,
Teranishi T., Yamada K., Yamaguchi H., and Sakurai
H.: “Gamow-Teller transition of proton-rich nucleus
24Si”, 7th Japan-China Joint Nuclear Physics Symposium, (University of Tsukuba), Tsukuba, Nov. (2009).
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., Fukuda N.,
Kubono S., Motobayashi T., Nakabayashi T., Nakao T.,
Okumura T., Ong H., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Mirror asymmetry for B(GT) of 24 Si induced by ThomasEhrman shift”, Tours Symposium on Nuclear Physics
and Astrophysics VII (TOURS 2009), (Konan University), Kobe, Nov. (2009).
Taniguchi Y., Kimura M., Enyo Y., Ikeda K., Horiuchi H.,
and Ideguchi E.: “Triaxial superdeformation in 40 Ar”,
JUSTIPEN-EFES Workshop on Unstable Nuclei, Wako,
Dec. (2009).
Dang N. D.: “The Selfconsistent Quasiparticle RPA and
Its Description of Thermal Pairing Properties in Nuclei”,
Multidisciplinary Workshop on the Random Phase Approximation and extensions, (Universite Pierre et Marie
Curie (Jussieu campus)), Paris, France, Jan. (2010).
Ichikawa Y., Onisi T. K., Suzuki D., Iwasaki H., Kubo
T., Naik V., Chakrabarti A., Aoi N., Brown A. B.,
Fukuda N., Kubono S., Motobayashi T., Nakabayashi
T., Nakamura T., Nakao T., Okumura T., Ong H.,
Suzuki H., Suzuki M. K., Teranishi T., Yamaguchi H.,
and Sakurai H.: “Proton-rich nuclear structure investigated by β decay of 24 Si”, ICHOR-EFES International
Symposium on New Facet of Spin-Isospin Responses(SIR2010), (University of Tokyo), Tokyo, Feb. (2010).
Ichikawa Y., Onisi T. K., Suzuki D., Iwasaki H., Kubo
T., Naik V., Chakrabarti A., Aoi N., Brown A. B.,
Fukuda N., Kubono S., Motobayashi T., Nakabayashi
T., Nakamura T., Nakao T., Okumura T., Ong H.,
Suzuki H., Suzuki M. K., Teranishi T., Yamaguchi H.,
and Sakurai H.: “Mirror asymmetry investigated by βdecay of proton-rich 24 Si”, International Symposium
on Forefronts of Researches in Exotic Nuclear Structures (Niigata2010), (Niigata University), Toka-machi,
Niigata Pref., Mar. (2010).
((Domestic)Conference), Beer G. A.,, Cargnelli M.,, Choi,,,S., Curceanu C. O.,
,
,
,
,
,
,
, Juhasz B., Kienle P., Marton J.,,,, Schmid P.,,,,,, Widmann E.,,,
Zmeskal J.:,, 5 (2005).
, Beer G. A.,, Cargnelli M.,, ChoiS., Curceanu C. O.,
,
,
,
,
,
,
,
,
,
, Juhasz B., Kienle P., Marton J.,,,, Schmid P.,,,,,, Widmann E.,,,
Zmeskal J.: “K
3d→2p X”,
61,
, 3 (2006).
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
, Choi S.,,,
Cargnelli M., Juhasz B., Kienle P., Marton J., Widmann
E., Zmeskal J., Schmid P., Beer G. A., Curceanu C. O.:
X
“K
I”,
61
,
, 3 (2006).
, Beer G. A.,, Buehler P., Cargnelli M.,, Choi S., Curceanu C. O.,, Guaraldo C.,,, Hirtl A.,, Iliescu M.,
,
,
,
,
,
, Kienle P.,
Marton J.,,,, Pietreanu D.,,,,
Sirghi D., Sirghi F.,, Widmann E.,,, Zmeskal J.: “Precision spectroscopy of Kaonic Helium-3 3d→2p X-rays(J-PARC E17
)”,
2006,
, 12 (2006).
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
, Beer G.
, Choi S.,,, Buehler P., Hirtl
A.,A., Cargnelli M., Kienle P., Marton J., Widmann E.,
Zmeskal J., Curceanu C. O., Guaraldo C., Iliescu M.,
Pietreanu D., Sirghi D., Sirghi F., Faso D., Busso L.,
Morra O.: “K
3
”,
2007
,
,
3 (2007).
, Beer G. A.,, Cargnelli M.,, ChoiS., Curceanu C. O.,
,
,
,
,
,
,
,
,
,

- 441 -

4

, Juhasz B., Kienle P., Marton J.,,,, Schmid P.,,,,,, Widmann E.,,,
Zmeskal J.:62,, 9(2007).
, Beer G. A.,, Buehler P., Cargnelli M.,, Choi S., Curceanu C. O.,, Guaraldo C.,,, Hirtl A.,, Iliescu M.,
,
,
,
,
,
, Kienle,,, Pietreanu
P., Marton J.,
D., Sirghi D., Sirghi F.,,,,, Widmann E.,,, Zmeskal J.: “JPARC
K
X
J-PARCE17”,
3(2007).
,,,(2007),
,

,

,

,
,

,

,
,

,

,

,

,

,

,

, 11

,
,

,

,

,
,

,

,
,
,
,
,
, Beer G. A.,, ChoiS.,,, Buehler P., Cargnelli M., Hirtl A.,
Kienle P., Marton J., Widmann E., Zmeskal J.,,
Curceanu C. O., Guaraldo C., Iliescu M., Pietreanu D.,
Sirghi D., Sirghi F., Faso D., Morra O., Busso L.: “K
3
III”,
2008
,
, 9 (2008).
,,,,: “Chemical
Reaction at Laser Ablation ; Nanosecond vs. Femtosecond”,
8,, 11(2008).
,,,,,,: “Application of fs-TOF
Lassmann T.,
MS for analyzing DICER function”, 31
81(BMB2008),, 12(2008).
,
,
,
,
,
,
,
,
,
,
,
,
: “
(I)”,
64
,
,
3
(2009).
,
,
,
,
,
,
,
,
,
,
,
,
: “
(II)”,
64,, 3 (2009).
,
,
,
,
,
: “
,

P-LIF
”,
56
, 3–4
(2009).
,
,

,
,

,

,

:

“
”,

- 442 -,
,5(2009).
,: “Hydrogenation reaction of the carbon
fragments produced by laser ablation of solid C60”,
25
,(
),
,6
(2009).
,
,
,
,
,
,
: “
”,
6
AMO
,
, 6 (2009).
,
,
,
,
,
,
,
,
: “
57
Mn
S/N
”, 200953,(),, 9 (2009).
,
,
,
,
,
,
,
,
: “
57
Mn
”, 200953,(),,9(2009).
,
,
,
,
,
,
,
,
: “
57
Mn
”, 200953,(),,9(2009).
,
,
,
,
,
,
: “
Au
”,
2009
,
,9
(2009).
,
: “
”,
10
,
, 11 (2009).
,
,
,
,
,
,
,
,
: “
57
Mn
S/N
”,
21
II
,
, 12 (2009).
,
,
,
,
,
,
: “
small RNA”,57,,
3 (2010).
,
,
,
,
,
,
: “Au
”,
65
,
, 3 (2010).
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
: “KEK-TRIAC
8
Li
”,
65
,
, 3 (2010).
,
,
,
,
,
,
,
,
,
,
,
: “
”,

5

,
,
,
,
,

,
,

65
,
, 3 (2010).
, Behr J. A.,,,, Levy P.,
,
,
,
,
,
,
, Pearson M.,
,
8
: “
Li
”,
6
,
, 3 (2010).
,
,
,
,
57
,
: “
Mn
”,
11
,
, 3 (2010).

,
,
,

,

- 443 -

6

Radioactive
RNC Isotope Physics Laboratory
Publications
Publications[Journal](Original Papers) *Subject to Peer Review
Nagae D., Asahi K., Ueno H., Kameda D., Takemura
M., Takase T., Yoshimi A., Sugimoto T., Nagatomo T.,
Kobayashi Y., Uchida M., Shimada K., Arai T., Inoue
T., Kagami S., and Hatakeyama N.: “Measurement ofElectric Quadrupole Moments for 31Al Using Spin Polarized RI Beams”, AIP Conf. Proc. 915, 853–856(2007).
Shimada K., Nagae D., Asahi K., Arai T., Takemura
M., Inoue T., Takase T., Kagami S., HatakeyamaN., Kobayashi Y., Ueno H., Yoshimi A., Kameda D.,
Nagatomo T., Sugimoto T., Kubono S., Yamaguchi H.,
Wakabayashi Y., Amadio G., Hayakawa S., Murata J.,
and Kawamura H.: “Production of Polarized Radioactive Beams via The Inverse-kinematics Reactions andTheir Applications”, AIP Conf. Proc. 915, 857–860(2007).
Ohnishi T., Kubo T., Kusaka K., Yoshida A., YoshidaK., Fukuda N., Ohtake M., Yanagisawa Y., Takeda H.,
Kameda D., Yamaguchi Y., Aoi N., Yoneda K., Otsu H.,
Takeuchi S., Sugimoto T., Kondo Y., Scheit H., Gono
Y., Sakurai H., Motobayashi T., Suzuki H., Nakao T.,
Kimura H., Mizoi Y., Matsushita M., Ieki K., Kuboki
T., Yamaguchi T., Suzuki T., Ozawa A., Moriguchi T.,
Yasuda Y., Nakamura T., Nannichi T., Shimamura T.,
Nakayama Y., Geissel H., Weick H., Nolen J. A., Tarasov
O. B., Nettleton A. S., Bazin D. P., Sherrill B. M.,
Morrissey D. J., and Mittig W.: “Identiﬁcation of New
Isotopes 125 Pd and 126 Pd Produced by In-Flight Fission of 345 MeV/nucleon 238 U: First Results from the
RIKEN RI Beam Factory”, J. Phys. Soc. Jpn. 77, No.
8, pp. 083201-1–083201-4 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bazilevsky A. V.,
Bunce G. M., Deshpande A., Enyo H., Fields D. E.,
Fox B., Fujiwara K., Fukao Y., Goto Y., Gross P. M.,
Hasuko K., Heuser J. M., Horaguchi T., Ichihara T.,
Imai K., Inoue Y., Ishihara M., Jinnouchi O., KamiharaN., Kaneta M., Kanoh H., Kawall D., Kiyomichi A.,
Kobayashi H., Kurita K., Mao Y., Murata J., Nakagawa
I., Nakano K., Onishi H., Okada H., Okada K., Rykov V.
L., Saito N., Sato H., Shibata T., Shoji K., Tabaru T.,
Taketani A., Tanida K., Togawa M., Tojo J., Torii H.,
Wagner M. M., Watanabe Y., Xie W., and Yokkaichi
S.: “Cold Nuclear Matter Eﬀects on J/ψ Production as Constrained by Deuteron-Gold Measurements at√
sNN = 200 GeV”, Phys. Rev. C 77, 024912-1–02491215 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K., Fukao
Y., Goto Y., Gross P. M., Hachiya T., Hasuko K., Heuser
J. M., Horaguchi T., Ichihara T., Imai K., Inoue Y.,

Ishihara M., Jinnouchi O., Kajihara F., Kamihara N.,
Kaneta M., Kanoh H., Kawall D., Kiyomichi A., Kurita
K., Mao Y., Murata J., Nakagawa I., Nakano K., Onishi
H., Okada H., Okada K., Rykov V. L., Saito N., Sato H.,
Shibata T., Shoji K., Tabaru T., Taketani A., Tanida K.,
Togawa M., Tojo J., Torii H., Tsuchimoto Y., Wagner
M. M., Watanabe Y., Xie W., and Yokkaichi S.: “Quantitative Constraints on the Transport Properties of Hot
Partonic Matter from Semi-Inclusive Single High Transverse Momentum Pion Suppression in Au+Au Collisions√
at sNN = 200 GeV”, Phys. Rev. C 77, 064907-1–
064907-12 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K., Fukao
Y., Goto Y., Gross P. M., Hachiya T., Hasuko K., Heuser
J. M., Horaguchi T., Ichihara T., Imai K., Inoue Y.,
Ishihara M., Jinnouchi O., Kajihara F., Kamihara N.,
Kaneta M., Kanoh H., Kawall D., Kiyomichi A., Kurita
K., Mao Y., Murata J., Nakagawa I., Nakano K., Onishi
H., Okada H., Okada K., Rykov V. L., Saito N., Sato H.,
Shibata T., Shoji K., Tabaru T., Taketani A., Tanida K.,
Togawa M., Tojo J., Torii H., Tsuchimoto Y., Wagner
M. M., Watanabe Y., Xie W., and Yokkaichi S.: “Dihadron azimuthal correlations in Au+Au collisions at√
sNN = 200 GeV”, Phys. Rev. C 78, 014901-1–01490142 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bazilevsky A. V.,
Bunce G. M., Deshpande A., Enyo H., Fields D. E.,
Fox B., Fujiwara K., Fukao Y., Goto Y., Gross P. M.,
Hachiya T., Hasuko K., Heuser J. M., Horaguchi T.,
Ichihara T., Imai K., Inoue Y., Ishihara M., Jinnouchi
O., Kajihara F., Kamihara N., Kaneta M., Kanoh H.,
Kawall D., Kiyomichi A., Kobayashi H., Kurita K., Mao
Y., Murata J., Nakagawa I., Nakano K., Onishi H.,
Okada H., Okada K., Rykov V. L., Saito N., Sato H.,
Shibata T., Shoji K., Tabaru T., Taketani A., Tanida
K., Togawa M., Tojo J., Torii H., Tsuchimoto Y.,
Wagner M. M., Watanabe Y., Xie W., and Yokkaichi
S.: “Charged hadron multiplicity ﬂuctuations in Au+Au√
and Cu+Cu collisions from sNN = 22.5 to 200 GeV”,
Phys. Rev. C 78, 044902-1–044902-15 (2008).
Afanasiev S., Akiba Y., Aoki K., Bunce G. M., DeshpandeA., Enyo H., Fields D. E., Fukao Y., Goto Y., Gross P.
M., Hachiya T., Hasuko K., Heuser J. M., Horaguchi
T., Ichihara T., Imai K., Ishihara M., Jinnouchi O.,
Kajihara F., Kamihara N., Kaneta M., Kiyomichi A.,
Kurita K., Murata J., Onishi H., Okada H., Okada K.,
Rykov V. L., Saito N., Sato H., Shibata T., Shoji K.,
Tabaru T., Taketani A., Tanida K., Togawa M., TojoJ., Torii H., Tsuchimoto Y., Wagner M. M., WatanabeY., Xie W., and Yokkaichi S.: “Source breakup dynam√
ics in Au+Au Collisions at sNN =200 GeV via threedimensional two-pion source imaging”, Phys. Rev. Lett.
100, 232301-1–232301-6 (2008).
Afanasiev S., Akiba Y., Aoki K., Bunce G. M., Deshpande- 444 -

1

A., Enyo H., Fields D. E., Fukao Y., Goto Y., Gross P.
M., Hachiya T., Hasuko K., Heuser J. M., Horaguchi
T., Ichihara T., Imai K., Ishihara M., Jinnouchi O.,
Kajihara F., Kamihara N., Kaneta M., Kiyomichi A.,
Kurita K., Murata J., Onishi H., Okada H., Okada K.,
Rykov V. L., Saito N., Sato H., Shibata T., Shoji K.,
Tabaru T., Taketani A., Tanida K., Togawa M., Tojo J.,
Torii H., Tsuchimoto Y., Wagner M. M., Watanabe Y.,
Xie W., and Yokkaichi S.: “Particle-species dependent
modiﬁcation of jet-induced correlations in Au+Au col√lisions at sNN = 200 GeV”, Phys. Rev. Lett. 101,
082301-1–082301-6 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K., Fukao
Y., Goto Y., Gross P. M., Horaguchi T., Ichihara T.,
Imai K., Inoue Y., Ishihara M., Jinnouchi O., KamiharaN., Kaneta M., Kanoh H., Kawall D., Kiyomichi A.,
Kurita K., Mao Y., Murata J., Nakagawa I., Nakano
K., Onishi H., Okada H., Okada K., Rykov V. L.,
Saito N., Shibata T., Shoji K., Tabaru T., Taketani A.,
Tanida K., Togawa M., Tojo J., Torii H., Wagner M.
M., Watanabe Y., Xie W., and Yokkaichi S.: “J/ψ Pro√
duction in sNN = 200 GeV Cu+Cu Collisions”, Phys.
Rev. Lett. 101, 122301-1–122301-6 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Dairaku S., Deshpande A., Enyo H., Fields D. E.,
Fujiwara K., Fukao Y., Goto Y., Gross P. M., Horaguchi
T., Ichihara T., Ichimiya R., Imai K., Inoue Y., Ishihara
M., Jinnouchi O., Kametani S., Kamihara N., Kaneta
M., Kanoh H., Kawall D., Kiyomichi A., Kurita K.,
Kurosawa M., Li Z., Mao Y., Murata J., Nakagawa I.,
Nakano K., Onishi H., Okada H., Okada K., Onuki Y.,
Rykov V. L., Saito N., Sakashita K., Shibata T., Shoji
K., Tabaru T., Taketani A., Tanida K., Togawa M.,
Tojo J., Torii H., Wagner M. M., Watanabe Y., Xie W.,
and Yokkaichi S.: “Onset of π 0 suppression studied in√
Cu+Cu collisions at sNN = 22.4, 62.4, and 200 GeV”,
Phys. Rev. Lett. 101, 162301-1–162301-6 (2008).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K.,
Fukao Y., Goto Y., Gross P. M., Hachiya T., Hasuko K.,
Heuser J. M., Horaguchi T., Ichihara T., Imai K., Inoue
Y., Ishihara M., Jinnouchi O., Kajihara F., KamiharaN., Kaneta M., Kanoh H., Kawall D., Kiyomichi A.,
Kurita K., Mao Y., Murata J., Nakagawa I., Nakano K.,
Onishi H., Okada H., Okada K., Rykov V. L., Saito N.,
Sato H., Shibata T., Shoji K., Tabaru T., Taketani A.,
Tanida K., Togawa M., Tojo J., Torii H., Tsuchimoto Y.,
Wagner M. M., Watanabe Y., Xie W., and Yokkaichi S.:“Suppression pattern of neutral pions at high transverse√
momentum in Au+Au collisions at sNN = 200 GeV
and constraints on medium transport coeﬃcients”, Phys.
Rev. Lett. 101, 232301-1–232301-7 (2008).
Asahi K., Ueno H., Shimada K., Nagatomo T., Yoshimi
A., Nagae D., Kameda D., Uchida M., Inoue T.,

Hatakeyama N., Kagami S., Hasama Y., Suzuki K.,
Murata J., Kawamura H., Narita K., and Ishihara M.:“Nuclear Structure Studies with Polarized Radioactive
Beams”, AIP Conf. Proc. 1149, 90–99 (2009).
Yoshimi A., Asahi K., Inoue T., Uchida M., HatakeyamaN., Tsuchiya M., and Kagami S.: “Nuclear Spin Maser
at Highly Stabilized Low Magnetic Field and Search for
Atomic EDM”, AIP Conf. Proc. 1149, 249–252 (2009).
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., Fukuda N.,
Kubono S., Motobayashi T., Nakabayashi T., Nakao T.,
Okumura T., Ong H., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Investigation into behavior of weakly-bound proton via
B(GT) measurement for the β decay of 24 Si”, AIP Conf.
Proc. 1165, 98–101 (2009).
Kobayashi T., Matsuo Y., Nishimura M., Hayashizaki Y.,
and Kawai J.: “Hydrogenation of carbon fragments after
femtosecond laser ablation of solid C60 ”, Appl. Surf. Sci.
255, 9652–9654 (2009).
Nishimura M., Kobayashi T., Matsuo Y., Motobayashi T.,
Hayashizaki Y., and Kawai J.: “Dynamics of Ablation
Plasma induced by a Femtosecond Laser Pulse in Electric Fields”, Appl. Surf. Sci. 255, 9729–9733 (2009).
Nagatomo T., Shimada K., Asahi K., Balabanski D. L.,
Daugas J., Depuydt M., De
Rydt M., Gaudefroy L.,
Grevy S., Hasama Y., Ichikawa Y., Kameda D., MorelP., Perrot L., Stodel C., Thomas J. C., VanderheijdenW., Vermeulen N., Vingerhoets P., Yoshimi A., Neyens
G., and Ueno H.: “Electric quadrupole moment of theneutron-rich 33 Al”, Eur. Phys. J. A 42, No. 3, pp.
383–385 (2009).
Ichikawa Y., Kubo T., Aoi N., Naik V., ChakrabartiA., Fukuda N., Iwasaki H., Kubono S., Motobayashi
T., Nakabayashi T., Nakao T., Okumura T., Ong H.,
Onishi T., Suzuki D., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Betadecay study of Tz = −2 proton-rich nucleus 24 Si”, Eur.
Phys. J. A 42, 375–378 (2009).
Mizuno T., Yamada T., Tsuchida H., Nakai Y., and ItohA.: “Structure deformation dynamics of acetylene
molecules following electron loss and capture collisionsof 6 MeV O4+ ions”, J. Phys.: Con. Ser. 163, 0120391–012039-4 (2009).
Hata M., Akiyama T., Ikeda Y., Kawamura H., Narota
K., Ninomiya K., Ogawa N., Sato T., Seitaibashi E.,
Sekiguchi Y., Tsutsui R., Yazawa K., and Murata J.:“Recent results on short-range gravity experiment”, J.
Phys.: Con. Ser. 189, 012019-01–012019-10 (2009).
Ninomiya K., Akiyama T., Hata M., Ikeda Y., Kawamura
H., Narota K., Ogawa N., Sato T., Seitaibashi E.,
Sekiguchi Y., Tsutsui R., Yazawa K., and Murata J.:“New experimental technique for short-range gravity- 445 -

2

measurement”, J. Phys.: Con. Ser. 189, 012026-1–
012026-7 (2009).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Deshpande A., Enyo H., Fields D. E., Fujiwara K., Fukao
Y., Goto Y., Gross P. M., Horaguchi T., Ichihara T.,
Imai K., Inoue Y., Ishihara M., Jinnouchi O., KamiharaN., Kaneta M., Kanoh H., Kawall D., Kiyomichi A.,
Kurita K., Mao Y., Murata J., Nakagawa I., Nakano K.,
Onishi H., Okada H., Okada K., Rykov V. L., Saito N.,
Shibata T., Shoji K., Tabaru T., Taketani A., Tanida K.,
Togawa M., Tojo J., Torii H., Wagner M. M., WatanabeY., Xie W., and Yokkaichi S.: “Dilepton mass spectra√in p+p collisions at s = 200 GeV and the contribution
from open charm”, Phys. Lett. B 670, 313–320 (2009).
De Rydt M., Neyens G., Asahi K., Balabanski D. L.,
Daugas J., Depuydt M., Gaudefroy L., Grevy S.,
Hasama Y., Ichikawa Y., Morel P., Nagatomo T.,
Ohtsuka T., Perrot L., Shimada K., Stoedel C., ThomasJ., Ueno H., Utsuno Y., Wannes V., Vermeulen N.,
Vingerhoets P., and Yoshimi A.: “Precision measurement of the electric quadrupole moment of 31 Al anddetermination of the eﬀective proton charge in the sdshell”, Phys. Lett. B 678, 344–349 (2009).
Takeuchi S., Aoi N., Motobayashi T., Ota S., TakeshitaE., Suzuki H., Baba H., Fukui T., Hashimoto Y., Ieki
K., Imai N., Iwasaki H., Kanno S., Kondo Y., Kubo T.,
Kurita K., Minemura T., Nakamura T., Okumura T.,
Onishi T., Sakurai H., Shimoura S., Sugou R., SuzukiD., Suzuki M., Takashina M., Tamaki M., Tanaka K.,
Togano Y., and Yamada K.: “Low-Iying States in 32Mg
studied by proton inelastic scattering”, Phys. Rev. C
79, No. 5, pp. 054319-1–054319-11 (2009).
Zhu S., Janssens R. V., Fornal B., Freeman S. J., Honma
M., Broda R., Carpenter M. P., Deacon A. N., JacksonE., Kay B. P., Lauritsen T., Lister C. J., Mantica P. F.,
Otsuka T., Seweryniak D., Smith J. F., Steppenbeck D.,
and Wang X.: “High-lying, non-yrast shell structure in
52Ti”, Phys. Rev. C 80, 024318-1–024318-11 (2009).
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., Fukuda N.,
Kubono S., Motobayashi T., Nakabayashi T., Nakao T.,
Okumura T., Ong H., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Betadecay of the proton-rich nucleus 24 Si and its mirror
asymmetry”, Phys. Rev. C 80, 044302-1–044302-12(2009).
Adare A., Akiba Y., Aoki K., Asai J., Bunce G. M.,
Dairaku S., Deshpande A., Enyo H., Fields D. E.,
Fujiwara K., Fukao Y., Goto Y., Gross P. M., Horaguchi
T., Ichihara T., Ichimiya R., Imai K., Ishihara M.,
Kametani S., Kamihara N., Kawall D., Kurita K.,
Kurosawa M., Li Z., Mao Y., Murata J., Nakagawa I.,
Nakano K., Okada H., Okada K., Onuki Y., Rykov V. L.,
Saito N., Sakashita K., Shibata T., Shoji K., Taketani

A., Tanida K., Togawa M., Torii H., Watanabe Y., Xie
W., and Yokkaichi S.: “Inclusive cross section and double helicity asymmetry for π 0 production in p + p colli√
sions at s = 62.4 GeV”, Phys. Rev. D 79, 012003-1–
012003-11 (2009).
Nakano Y., Kondo C., Hatakeyama A., Nakai Y., Azuma
T., Komaki K., Yamazaki Y., Takada E., and Murakami
T.: “Polarization control in three-dimensional resonant
coherent excitation”, Phys. Rev. Lett. 102, 085502-1–
085502-4 (2009).
Mizuno T., Yamada T., Tsuchida H., Nakai Y., and ItohA.: “Measurement of kinetic energy release in CO fragmentation by charge-changing collisions of fast heavyions”, Phys. Rev. A 81, 012704-1–012704-6 (2010).
Steppenbeck D., Deacon A. N., Freeman S. J., Janssens R.
V., Zhu S., Carpenter M. P., Chowdhury P., Honma M.,
Lauritsen T., Lister C. J., Seweryniak D., Smith J. F.,
Tabor S. L., and Varley B. J.: “High-spin structures in
the neutron-rich isotopes 57−60 Mn”, Phys. Rev. C 81,
No. 1, pp. 014305-1–014305-21 (2010).
(Others)
Murata J., Akiyama T., Hata M., Hirayama Y., Ikeda
Y., Ishii T., Kameda D., Kawamura H., Mitsuoka
S., Miyatake H., Nagae D., Ninomiya K., Nitta M.,
Seitaibashi E., and Toyoda T.: “Test of time reversal
symmetry using polarized nuclei”, JAEA-Review 2009036, 62–63 (2009).

Oral Presentations
Oral Presentations((International) Conference etc.)
Takeuchi S., Shimoura S., Motobayashi T., Akiyoshi H.,
Ando Y., Aoi N., Fulop Z., Gomi T., Higurashi Y.,
Hirai M., Iwasa N., Iwasaki H., Iwata Y., Kobayashi H.,
Kurokawa M., Liu Z., Minemura T., Ozawa S., Sakurai
H., Serata M., Teranishi T., Yamada K., Yanagisawa
Y., and Ishihara M.: “Isobaric analog state of 14 Be”,
RIKEN-CNS RIBF International Workshop “Correlation and Condensation: New Features in Loosely Boundand Unbound Nuclear States”, Wako, Dec. (2005).
Motizuki Y.: “A prospect of theoretical and interdisciplinary r-process studies around RIBF”, RIBF users
meeting 2008, Wako, Nov. (2008).
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., Fukuda N.,
Kubono S., Motobayashi T., Nakabayashi T., Nakao T.,
Okumura T., Ong H., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Investigation into behavior of weakly-bound proton via
B(GT) measurement for the β decay of 24 Si”, International Conference on Nuclear Structure and Dynamics(NSD09), (University of Zagreb), Dubrovnik, Croatia,
May (2009).
Motizuki Y. and Dome-F g. c.: “Solar cycles and supernovae embedded in a Dome F ice core”, International
Astronomical Union 27th General Assembly, (Interna-- 446 -

3

tional Astronomical Union), Rio de Janeiro, Brazil, Aug.
(2009).
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., Fukuda N.,
Kubono S., Motobayashi T., Nakabayashi T., Nakao T.,
Okumura T., Ong H., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Betadecay of 24 Si and mirror asymmetry of Gamow-Tellertransition strength”, 3rd Joint Meeting of the Nuclear
Physics Divisions of the APS and JPS (Hawaii 2009),
Hawaii, USA, Oct. (2009).
Sasaki A., Wakui T., Furukawa T., Kazato M., Wada M.,
Sonoda T., Takamine A., Kobayashi T., Nishimura M.,
Ueno H., Yoshimi A., Aoi N., Nishimura S., Togano Y.,
Takechi M., Kondo Y., Hatakeyama A., Matsuura Y.,
Kato Y., Odahara A., Shimoda T., Asahi K., ShinozukaT., Motobayashi T., and Matsuo Y.: “Fluorescence detection system for nuclear laser spectroscopy of Rb in
superﬂuid helium”, 3rd Joint Meeting of the Nuclear
Physics Divisions of the APS and JPS (Hawaii 2009),
Hawaii, USA, Oct. (2009).
Ueno H., Yoshimi A., and Asahi K.: “RIPS upgrade andphysics programs”, 3rd Joint Meeting of the Nuclear
Physics Divisions of the APS and JPS (Hawaii 2009),
Hawaii, USA, Oct. (2009).
Baba H., Ichihara T., Ohnishi T., Takeuchi S., YoshidaK., Watanabe Y., Ota S., and Shimoura S.: “The New
DAQ System in RIKEN RIBF”, 3rd Joint Meeting of the
Nuclear Physics Divisions of the APS and JPS (Hawaii2009), Hawaii, USA, Oct. (2009).
Motizuki Y., Takahashi K., Nakai Y., Makishima K.,
Bamba A., Yano Y., Igarashi M., Motoyama H.,
Kamiyama K., Suzuki K., and Imamura T.: “A Dome
Fuji ice core recording both supernovae and solar cycles”, 2nd International Symposium on Dome Fuji Ice
Core and Related Topics, (National Institute of Polar
Research), Tachikawa, Nov. (2009).
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., FukudaN., Kubono S., Motobayashi T., Nakabayashi T., Nakao
T., Okumura T., Ong H., Suzuki H., Suzuki M.,
Teranishi T., Yamada K., Yamaguchi H., and Sakurai
H.: “Gamow-Teller transition of proton-rich nucleus
24Si”, 7th Japan-China Joint Nuclear Physics Symposium, (University of Tsukuba), Tsukuba, Nov. (2009).
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., Fukuda N.,
Kubono S., Motobayashi T., Nakabayashi T., Nakao T.,
Okumura T., Ong H., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Mirror asymmetry for B(GT) of 24 Si induced by ThomasEhrman shift”, Tours Symposium on Nuclear Physics
and Astrophysics VII (TOURS 2009), (Konan University), Kobe, Nov. (2009).
Ichikawa Y., Onisi T. K., Suzuki D., Iwasaki H., Kubo

T., Naik V., Chakrabarti A., Aoi N., Brown A. B.,
Fukuda N., Kubono S., Motobayashi T., Nakabayashi
T., Nakamura T., Nakao T., Okumura T., Ong H.,
Suzuki H., Suzuki M. K., Teranishi T., Yamaguchi H.,
and Sakurai H.: “Proton-rich nuclear structure investigated by β decay of 24 Si”, ICHOR-EFES International
Symposium on New Facet of Spin-Isospin Responses(SIR2010), (University of Tokyo), Tokyo, Feb. (2010).
Ichikawa Y., Onisi T. K., Suzuki D., Iwasaki H., Kubo
T., Naik V., Chakrabarti A., Aoi N., Brown A. B.,
Fukuda N., Kubono S., Motobayashi T., Nakabayashi
T., Nakamura T., Nakao T., Okumura T., Ong H.,
Suzuki H., Suzuki M. K., Teranishi T., Yamaguchi H.,
and Sakurai H.: “Mirror asymmetry investigated by βdecay of proton-rich 24 Si”, International Symposium
on Forefronts of Researches in Exotic Nuclear Structures (Niigata2010), (Niigata University), Toka-machi,
Niigata Pref., Mar. (2010).
((Domestic )Conference), Beer G. A.,, Cargnelli M.,, Choi,,,S., Curceanu C. O.,
,
,
,
,
,
,
, Juhasz B., Kienle P., Marton J.,,,, Schmid P.,,,,,, Widmann E.,,,
Zmeskal J.:,, 5 (2005).
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
, Bhang H., Choi S., Kim J., Yim H.,,,N)
Widmann E., Kienle P.: “4 He(K−stopped
1 ”,
61
,(
),
,3
(2006).
, Beer G. A.,, Cargnelli M.,, ChoiS., Curceanu C. O.,
,
,
,
,
,
,
,
,
,
, Juhasz B., Kienle P., Marton J.,,,, Schmid P.,,,,,, Widmann E.,,,
Zmeskal J.: “K
3d→2p X”,
61,
, 3 (2006).
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
, Choi S.,,,
Cargnelli M., Juhasz B., Kienle P., Marton J., Widmann
E., Zmeskal J., Schmid P., Beer G. A., Curceanu C. O.:
“K
X
I”,
61
,
, 3 (2006).
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
, Bhang H., Choi S., Kim J., Yim H.,,,N)
Widmann E., Kienle P.: “4 He(K−stopped- 447 -

4

4 ”,
2006
,(
),
, 9 (2006).
, Beer G. A.,, Buehler P., Cargnelli M.,, Choi S., Curceanu C. O.,, Guaraldo C.,,, Hirtl A.,, Iliescu M.,
,
,
,
,
,
, Kienle P.,,,, Pietreanu D.,
Marton J.,
Sirghi D., Sirghi F.,,,,, Widmann E.,,, Zmeskal J.: “Precision spectroscopy of Kaonic Helium-3 3d→2p X-rays(J-PARC E17
)”,
2006,
, 12
(2006).
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
, Bhang H., Choi S., Kim J., Yim H.,,
Widmann E., Kienle P.: “4 He(K−,N)
stopped
(6)”,
2007
,(
),
, 3 (2007).
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
, Beer G.
, Choi S.,,, Buehler P., Hirtl
A.,A., Cargnelli M., Kienle P., Marton J., Widmann E.,
Zmeskal J., Curceanu C. O., Guaraldo C., Iliescu M.,
Pietreanu D., Sirghi D., Sirghi F., Faso D., Busso L.,
Morra O.: “K
3
”,
2007
,
,
(2007).
3, Beer G. A.,, Cargnelli M.,, ChoiS., Curceanu C. O.,
,
,
,
,
,
,
,
,
,
, Juhasz B., Kienle P., Marton J.,,,, Schmid P.,,,,,, Widmann E.,
,
,
62
,
, 9
Zmeskal J.:(2007).
, Beer G. A.,, Buehler P., Cargnelli M.,, Choi S., Curceanu C. O.,, Guaraldo C.,,, Hirtl A.,, Iliescu M.,
,
,
,
,
,
, Kienle
P., Marton J.,,,, Pietreanu,,,
D., Sirghi D., Sirghi F.,, Widmann E.,,, Zmeskal J.: “JK
X
PARC
J-PARCE17”,
3(2007).
,(2007),
,

,
,

,
,

,
,

,

,
,
,

, 11
,
,
,

,
,
,

- 448 -, Bhang H., Choi S., Kim J., Yim H.,
Widmann E., Kienle P.: “4 He
K−
(1)”,
,3

63

,

,(

),

(2008).
,

,
,

,

,

,

,

,

,

,3

(2008).
,
,

,
: “

”,
63
,

,
,

,

,

,

,

,

,
: “

3
”,

63
,

,

,

,3

,

,

(2008).
,

,
,
,
: “3
(3D-RCE)
Fe24+
2
”,
2008
,
, 9 (2008).
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
, Beer G. A.,, ChoiS.,,, Buehler P., Cargnelli M., Hirtl A.,
Kienle P., Marton J., Widmann E., Zmeskal J.,,
Curceanu C. O., Guaraldo C., Iliescu M., Pietreanu D.,
Sirghi D., Sirghi F., Faso D., Morra O., Busso L.: “K
3
III”,
2008
,
, 9 (2008).
,
,
,
,
,
,
,
,
,
,
,
,
: “
(I)”,
64
,
,
3 (2009).
,
,
,
,
,
,
,
,
,
,
,
,
: “
(II)”,
64,, 3 (2009).
,
,
,
,
,
,
,
,
,
,
: “
3
”,
64
,
, 3 (2009).
,
,
,
,
,
: “
”,
2009
, , 3 (2009).
,
,
,
,
,
: “
,

P-LIF
”,
56
, 3–4
(2009).
,
,
,
,

,
,

,

,

,

,

,

: “
”,

2009
,

,

,
,

,5

(2009).
,

,

:

5

“

,
”,

,
,

,5

,

(2009).
: “
”,

,
,
,

,7

(2009).

: “,, Behr J. A.,,,, Levy P.,
,
,
,
,
,
, Pearson M.,
,
8
: “
Li
”,
6
,
,3
(2010).
,
,
,
: “

,
,
,
,

”,
,

,7

(2009).

small RNA

: “

,(

”,

,3
,
, 10 (2009).
: “
”,
, 11
(2009).
,
,
,

,

,(
,

: “
”,
32
, 11 (2009).
,
,

),
,

,

”,
),

(2010).

:

“
12

19

”,

,(

),

32
, 11
(2009).

: “
”,
, 12

,
(2009).
: “

SEP
STE

,

”,
(2010).

,1: “”, JSR(2010).
,
“
”,
,
: “

,

,
,
Li
,
,
,
,

,3

,3

:
(2010).

,,

small RNA,,,, Levy P.,, Pearson M.,
,
8
Li
”,
65

,

,

,

,

,

, 2
,

,
,

57

(2010).
,

,

,

2010
,

(2010).
, Behr J. A.,,,: “TRIUMF-ISAC
,3
,

8

,

,

”,
3

,

,

,

,

,
,
,
,
,
: “KEK-TRIAC”,, 3 (2010).
,
,
,
,
,
: “
2”,
65
(2010).
,,
65,- 449 -

6Superheavy
RNC Element Laboratory

Z., Ishii Y., Sato T., Nishinaka I., Kikuchi T., Haba
H., Kudou Y., Sato N., Oura Y., Akiyama K., Ooe K.,
Fujisawa H., Shinohara A., Goto S., Kudo H., Araki M.,
Nishikawa M., Yokoyama A., and Nagame Y.: “Anionexchange experiment of Db with 0.31 M HF/0.10 M
HNO3 solution”, JAEA-Review 2009, No. 036, pp. 67–
68 (2009).

Publications
Publications[]
Journal(Original Papers) *Subject to Peer Review
Haba H., Akiyama K., Tsukada K., Asai M., ToyoshimaA., Yaita T., Hirata M., Sueki K., and Nagame Y.:“Chloride Complexation of Zr and Hf in HCl Investigated by Extended X-ray Absorption Fine Structure Spectroscopy: Toward Characterization of Chloride
Complexation of Element 104, Rutherfordium (Rf)”,
Bull. Chem. Soc. Jpn. 82, No. 6, pp. 698–703 (2009).
Haba H., Kaji D., Komori Y., Kudou Y., Morimoto K.,
Morita K., Ooe K., Ohzeki K., Sato N., Shinohara A.,
and Yoneda A.: “RIKEN Gas-ﬁlled Recoil Ion Separator (GARIS) as a promising interface for superheavy element chemistry : Production of element 104, 261Rf,
using the GARIS/gas-jet system”, Chem. Lett. 38, No.
5, pp. 426–427 (2009).
Kasamatsu Y., Toyoshima A., Asai M., Tsukada K., Li Z.,
Ishii Y., Toume H., Sato T., Kikuchi T., Nishinaka I.,
Nagame Y., Haba H., Kikunaga H., Kudou Y., Oura Y.,
Akiyama K., Sato W., Ooe K., Fujisawa H., Shinohara
A., Goto S., Hasegawa Taichi ., Kudo H., Nanri T.,
Araki M., Kinoshita N., Yokoyama A., Fan F., Qin Z.,
Duellman C. E., Schaedel M., and Kratz J. V.: “Anionic
Fluoro Complex of Element 105, Db”, Chem. Lett. 38,
No. 11, pp. 1084–1085 (2009).
Toyoshima A., Kasamatu Y., Tsukada K., Asai M.,
Kitatsuji Y., Ishii Y., Toume H., Nishinaka I., Haba
H., Ooe K., Sato W., Shinohara A., Akiyama K.,
and Nagame Y.: “Oxidation of element 102, nobelium,with ﬂow electrolytic column chromatography on an
atom-at-a-time scale”, J. Am. Chem. Soc. 131, 9180–
9181 (2009).
Akiyama K., Haba H., Tsukada K., Asai M., ToyoshimaA., Sueki K., Nagame Y., and Katada M.: “A metallofullerene that encapsulates 225Ac”, J. Radioanal. Nucl.
Chem. 280, No. 2, pp. 329–331 (2009).
Inamura T. and Haba H.: “Search for a ”3.5-eV isomer”
in 229 Th in a hollow-cathode electric discharge”, Phys.
Rev. C 79, No. 3, pp. 034313-1–034313-10 (2009).
(Others)
Asai M., Tsukada K., Kasamatsu Y., Sato T., ToyoshimaA., Ishii Y., Takahashi R., Nagame Y., Ishii T.,
Nishinaka I., Kaji D., Morimoto K., and Kojima Y.:“Alpha-gamma spectroscopy of 259 Rf produced by using a mixed Cf target”, JAEA-Review 2009, No. 036,
pp. 37–38 (2009).
Nishinaka I., Kasamatsu Y., Tanikawa M., Goto S.,
and Asai M.: “Sub-barrier fusion hindrance in 19 F +209
Bi reaction”, JAEA-Review 2009, No. 036, pp. 60–
61 (2009).
Kasamatsu Y., Toyoshima A., Asai M., Tsukada K., Li

Oral Presentations
Oral Presentations((International) Conference etc.)
Ooe K., Yahagi W., Komori Y., Fujisawa H., Kikunaga
H., Yoshimura T., Sato W., Takahashi N., Takahisa
K., Haba H., Kudou Y., Ezaki Y., and Shinohara A.:“Studies of Extraction Behavior of Tungsten toward Solution Chemistry of Seaborgium (Element 106)”, International Workshop on Molecular Information and Dynamics 2008, (Osaka University Global COE Program ),Taipei, Taiwan, Nov. (2008).
Kasamatsu Y., Toyoshima A., Asai M., Tsukada K., Li Z.,
Ishii Y., Sato T., Nishinaka I., Kikuchi T., Nagame Y.,
Haba H., Kikunaga H., Kudou Y., Sato N., Oura Y.,
Akiyama K., Sato W., Ooe K., Fujisawa H., Shinohara
A., Goto S., Kudo H., Araki M., Kinoshita N., Nishikawa
M., Yokoyama A., Fan F., Qin Z., and Duellmann C.
E.: “Anion-exchange experiment of Db with AIDAII”, 7th Workshop on the Chemistry of the Heaviest
Elements, (Johannes Gutenberg - Universitaet Mainz),
Mainz, Germany, Oct. (2009).
Ooe K., Yahagi W., Komori Y., Fujisawa H., TakayamaR., Kikunaga H., Yoshimura T., Takahashi N., Haba H.,
Kudou Y., Ezaki Y., Takahisa K., and Shinohara A.:“Solvent Extraction Studies of Molybdenum and Tungsten as Homologues of Seaborgium (Element 106)”, 7thWorkshop on the Chemistry of the Heaviest Elements,(Mainz University), Mainz, Germany, Oct. (2009).
((Technical)Document),,,,, Li Z.,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
, Fan F.,
,
: “
105
(Db)
HF/HNO3
”,
89
,(
),
,3
(2009).
,,,,, Li Z.,,,,,: “106
Sg
”,
89
,(
),
,3
(2009).
,, Li Z.,,,,,,, Fan F.: “Rf
Zr
Hf
α-HiB
”, 200953,(),,9(2009).
,,,, Li Z.,
,
,
,
,
,
,
,
,
,
,
,
,

- 450 -

1

,,
“HF/HNO3”, 2009,(,,α53(2009).
,,,,,: “106

,

,
105

),

,9

,
Db
53
(2009).

: “”, 2009
,(

),

,

,

,

,

,

”, 2009
,
,

,(
,
,

),
,

,

209

),
,9
: “nat Hf”, 2009

Bi

,

,
: “
”, 2009
,(
,
,

,

53
(2009).
,,
Fm, Es

,9

,(
,

,9

,9
,
,

53
(2009).
, Li Z.,

: “Db

Nb
Ta
”, 2009
(
),
,
,
: “Cf
”, 2009
,(
,
,
53

:

,
,

),
,

,
,

53
(2009).

),, 9 (2009).
, Li Z.,
,
,
,
,
101
53
, 9 (2009).
,: “19 F +”, 2009,(),

53, 9 (2009).
: “Development of the rapid α detection apparatus for aqueous chemistry of superheavy elements at
RIKEN”,
2010,,2(2010).

- 451 -

2

Accelerator Group
RNC(2009).
,,

Publications
Publications[
Proc.]
Book• Proceedings(Others)
Fukunishi N., Fujimaki M., Watanabe T., Kumagai K.,
Komiyama M., Watanabe H., Goto A., Hasebe H.,
Higurashi Y., Ikezawa E., Kageyama T., Kamigaito
O., Kase M., Kuboki H., Kidera M., Nagase M., Maie
T., Nakagawa T., Ohnishi J., Okuno H., SakamotoN., Sekiguchi K., Suda K., Suzuki H., Wakasugi M.,
Watanabe Y., Yokouchi S., Yano Y., and Yamada K.:“Operating experience with the RIKEN Radioactive Isotope Beam Factory”, Proceedings of the 2009 Particle
Accelerator Conference (PAC09), Vancouver, Canada,
2009–5, PAC09 Editor, Vancouver, pp. MO3GRI0-1–
MO3GRI0-5 (2009).

,
”,

),
,
,
RIBF

,
,

6
,8
,

,

,

,
,(

(2009).
,
,

,

,

,

,(
(2009).
,,,,
6, 8 (2009).

,

: “

,

: “
”,
6
,8

),
,
: “
,(

,
RIBF

,

,
”,

),

Oral Presentations
Oral Presentations((International) Conference etc.)
Fukunishi N., Fujimaki M., Watanabe T., Kumagai K.,
Komiyama M., Watanabe H., Goto A., Hasebe H.,
Higurashi Y., Ikezawa E., Kageyama T., Kamigaito
O., Kase M., Kuboki H., Kidera M., Nagase M., Maie
T., Nakagawa T., Ohnishi J., Okuno H., SakamotoN., Sekiguchi K., Suda K., Suzuki H., Wakasugi M.,
Watanabe Y., Yokouchi S., Yano Y., and Yamada K.:“Operating experience with the RIKEN Radioactive Isotope Beam Factory”, 23rd Particle Accelerator Conference (PAC09), Vancouver, Canada, May (2009).
((Domestic)Conference),
Vorozhtsov S., Perepelkin E., Vorozhtsov A.,,: “Beam simulations in computermodelled 3D ﬁelds for RIKEN AVF cyclotron upgrade”,
6,(),, 8 (2009).
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
: “
(RILAC)
BT
”,
6
,(
),
,8
(2009).
,
,
,
,
,
,
,
,
: “
RIBF
RILAC2”,6,, 8 (2009).
,
,
,
,
: “
SQUID
”,
6
,(
),
,8
(2009).
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
: “RI
”,
6
,
,8

- 452 -

1

Accelerator R&D Team
RNC

,
,

Publications
Publications[Book • Proceedings
Proc.](Others)
Fukunishi N., Fujimaki M., Watanabe T., Kumagai K.,
Komiyama M., Watanabe H., Goto A., Hasebe H.,
Higurashi Y., Ikezawa E., Kageyama T., Kamigaito
O., Kase M., Kuboki H., Kidera M., Nagase M., Maie
T., Nakagawa T., Ohnishi J., Okuno H., SakamotoN., Sekiguchi K., Suda K., Suzuki H., Wakasugi M.,
Watanabe Y., Yokouchi S., Yano Y., and Yamada K.:“Operating experience with the RIKEN Radioactive Isotope Beam Factory”, Proceedings of the 2009 Particle
Accelerator Conference (PAC09), Vancouver, Canada,
2009–5, PAC09 Editor, Vancouver, pp. MO3GRI0-1–
MO3GRI0-5 (2009).

6
,8

,
,

,
: “
,(

,
RIBF

,

,
”,

),

(2009).

Oral Presentations
Oral Presentations((International) Conference etc.)
Fukunishi N., Fujimaki M., Watanabe T., Kumagai K.,
Komiyama M., Watanabe H., Goto A., Hasebe H.,
Higurashi Y., Ikezawa E., Kageyama T., Kamigaito
O., Kase M., Kuboki H., Kidera M., Nagase M., Maie
T., Nakagawa T., Ohnishi J., Okuno H., SakamotoN., Sekiguchi K., Suda K., Suzuki H., Wakasugi M.,
Watanabe Y., Yokouchi S., Yano Y., and Yamada K.:“Operating experience with the RIKEN Radioactive Isotope Beam Factory”, 23rd Particle Accelerator Conference (PAC09), Vancouver, Canada, May (2009).
((Domestic)Conference)
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
: “RI
”,
5
/ 33
,(
),
,8
(2008).
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
: “
(RILAC)
BT
”,
6
,(
),
,8
(2009).
,
,
,
,
,
,
,
,
: “
RIBF
RILAC2”,6,, 8 (2009).
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
: “RI
”,
6
,
,8
(2009).

- 453 -1

RNCIon Source Team

,
,
”,
6
(2009).
: “ECR

Publications
Publications[Book • Proceedings
Proc.](Others)

: “RI
,

,8
RILAC

”, 2009

Fukunishi N., Fujimaki M., Watanabe T., Kumagai K.,
Komiyama M., Watanabe H., Goto A., Hasebe H.,
Higurashi Y., Ikezawa E., Kageyama T., Kamigaito
O., Kase M., Kuboki H., Kidera M., Nagase M., Maie
T., Nakagawa T., Ohnishi J., Okuno H., SakamotoN., Sekiguchi K., Suda K., Suzuki H., Wakasugi M.,
Watanabe Y., Yokouchi S., Yano Y., and Yamada K.:“Operating experience with the RIKEN Radioactive Isotope Beam Factory”, Proceedings of the 2009 Particle
Accelerator Conference (PAC09), Vancouver, Canada,
2009–5, PAC09 Editor, Vancouver, pp. MO3GRI0-1–
MO3GRI0-5 (2009).

53(2009).

,(

),

,9

Oral Presentations
Oral Presentations((International) Conference etc.)
Fukunishi N., Fujimaki M., Watanabe T., Kumagai K.,
Komiyama M., Watanabe H., Goto A., Hasebe H.,
Higurashi Y., Ikezawa E., Kageyama T., Kamigaito
O., Kase M., Kuboki H., Kidera M., Nagase M., Maie
T., Nakagawa T., Ohnishi J., Okuno H., SakamotoN., Sekiguchi K., Suda K., Suzuki H., Wakasugi M.,
Watanabe Y., Yokouchi S., Yano Y., and Yamada K.:“Operating experience with the RIKEN Radioactive Isotope Beam Factory”, 23rd Particle Accelerator Conference (PAC09), Vancouver, Canada, May (2009).
Seto Y., Kishi S., Ohmori T., Kanamori M., Tsuge K.,
Okumura A., Takada Y., Ezawa N., Watanabe S.,
Hashimoto H., Kidera M., and Takahashi K.: “On-site
detection of chemical warfare agents by mass spectrometry and ion mobility spectrometry”, 57th ASMS Conference on Mass Spectrometry and Allied Topics, (ASMS),
Philadelphia, USA, May–June (2009).
((Domestic )Conference)
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
: “RI
”,
5
/ 33
,(
),
,8
(2008).
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
: “
(RILAC)
BT
”,
6
,(
),
,8
(2009).
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,

- 454 -1

RNCRILAC Team

Publications
Publications[Journal](Original Papers) *Subject to Peer Review
Kasuga H., Ohmori H., Mishima T., Watanabe Y., and Lin
W.: “Investigation on mirror surface grinding characteristics of SiC materials”, J. Ceram. Process. Res. 10,
No. 3, pp. 351–354 (2009).
Kasuga H., Ohmori H., Lin W., Watanabe Y., MishimaT., and Doi T.: “Eﬃcient and smooth grinding characteristics of monocrystalline 4H-SiC wafer”, J. Vac. Sci.
Technol. B 27, No. 3, pp. 1578–1582 (2009).
Kasuga H., Ohmori H., Watanabe Y., and Mishima T.:“Surface characteristics of eﬃcient-ground alumina andzirconia ceramics for dental applications”, Key Eng.
Mater. 404, 69–75 (2009).
Kasuga H., Ohmori H., Lin W., Watanabe Y., Mishima T.,
and Doi T.: “Eﬃcient super-smooth ﬁnishing characteristics of sic materials through the use of ﬁne-grinding”,
Key Eng. Mater. 404, 137–141 (2009).
[Book • Proceedings
Proc.](Others)
Fukunishi N., Fujimaki M., Watanabe T., Kumagai K.,
Komiyama M., Watanabe H., Goto A., Hasebe H.,
Higurashi Y., Ikezawa E., Kageyama T., Kamigaito
O., Kase M., Kuboki H., Kidera M., Nagase M., Maie
T., Nakagawa T., Ohnishi J., Okuno H., SakamotoN., Sekiguchi K., Suda K., Suzuki H., Wakasugi M.,
Watanabe Y., Yokouchi S., Yano Y., and Yamada K.:“Operating experience with the RIKEN Radioactive Isotope Beam Factory”, Proceedings of the 2009 Particle
Accelerator Conference (PAC09), Vancouver, Canada,
2009–5, PAC09 Editor, Vancouver, pp. MO3GRI0-1–
MO3GRI0-5 (2009).

Oral Presentations
Oral Presentations((International) Conference etc.)
Fukunishi N., Fujimaki M., Watanabe T., Kumagai K.,
Komiyama M., Watanabe H., Goto A., Hasebe H.,
Higurashi Y., Ikezawa E., Kageyama T., Kamigaito
O., Kase M., Kuboki H., Kidera M., Nagase M., Maie
T., Nakagawa T., Ohnishi J., Okuno H., SakamotoN., Sekiguchi K., Suda K., Suzuki H., Wakasugi M.,
Watanabe Y., Yokouchi S., Yano Y., and Yamada K.:“Operating experience with the RIKEN Radioactive Isotope Beam Factory”, 23rd Particle Accelerator Conference (PAC09), Vancouver, Canada, May (2009).
Kasuga H., Ohmori H., Katahira K., Watanabe Y.,
and Mishima T.: “Eﬃcient and precise grinding of silicon nitride (Si3 N4 ) ceramics”, 42nd CIRP Conference on
Manufacturing Systems, Grenoble, France, June (2009).
Kasuga H., Ohmori H., Watanabe Y., and Mishima T.:“Grinding characteristics of optical glass for surface
roughness reduction”, 5th International Conference on

Leading Edge Manufacturing in 21st Century (LEM21),(Japan Society of Mechanical Engineers), Osaka, Dec.
(2009).
(Domestic()Conference)
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
: “RI
”,
5
/ 33
,(
),
, 8 (2008).
,,,,: “Si3 N4
”,
2009
,(
),
, 3 (2009).
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
: “
(RILAC)
BT
”,
6
,(
),
, 8 (2009).
,
,
,
,
,
,
,
,
: “
RIBF
RILAC2”,
6,,8(2009).
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
: “RI
”,
6
,
,8
(2009).
,
,
,
,
,
,
,
,
: “
”,
6
,(
),
, 8 (2009).
,
,
,
,
,
,
,
,
,
,
: “
RIBF
”,
6
,(
),
,8
(2009).
,
,
,
,
: “
EPICS
RI
”,
6
,(
),
, 8 (2009).
,
,
,
: “
”, 2009,(),, 9 (2009).

- 455 -

1

RNC Cyclotron Team,,

Publications
Publications[Book • Proceedings
Proc.](Others)
Fukunishi N., Fujimaki M., Watanabe T., Kumagai K.,
Komiyama M., Watanabe H., Goto A., Hasebe H.,
Higurashi Y., Ikezawa E., Kageyama T., Kamigaito
O., Kase M., Kuboki H., Kidera M., Nagase M., Maie
T., Nakagawa T., Ohnishi J., Okuno H., SakamotoN., Sekiguchi K., Suda K., Suzuki H., Wakasugi M.,
Watanabe Y., Yokouchi S., Yano Y., and Yamada K.:“Operating experience with the RIKEN Radioactive Isotope Beam Factory”, Proceedings of the 2009 Particle
Accelerator Conference (PAC09), Vancouver, Canada,
2009–5, PAC09 Editor, Vancouver, pp. MO3GRI0-1–
MO3GRI0-5 (2009).

6
,8

,
,

,
: “
,(

,
RIBF

,

,
”,

),

(2009).

Oral Presentations
Oral Presentations((International) Conference etc.)
Fukunishi N., Fujimaki M., Watanabe T., Kumagai K.,
Komiyama M., Watanabe H., Goto A., Hasebe H.,
Higurashi Y., Ikezawa E., Kageyama T., Kamigaito
O., Kase M., Kuboki H., Kidera M., Nagase M., Maie
T., Nakagawa T., Ohnishi J., Okuno H., SakamotoN., Sekiguchi K., Suda K., Suzuki H., Wakasugi M.,
Watanabe Y., Yokouchi S., Yano Y., and Yamada K.:“Operating experience with the RIKEN Radioactive Isotope Beam Factory”, 23rd Particle Accelerator Conference (PAC09), Vancouver, Canada, May (2009).
((Domestic )Conference)
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
: “RI
”,
5
/ 33
,(
),
,8
(2008).
,
,
,
,
,
,
,
,
: “
RIBF
RILAC2”,6,, 8 (2009).
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
: “RI
”,
6
,
,8
(2009).
,
,
,
,
,
,
,
,
,
,
: “
RIBF
”,
6
,(
),
,8
(2009).

- 456 -

1

Beam Dynamics& Diagnostics Team
RNC

Higurashi Y., Ikezawa E., Kageyama T., Kamigaito
O., Kase M., Kuboki H., Kidera M., Nagase M., Maie
T., Nakagawa T., Ohnishi J., Okuno H., SakamotoN., Sekiguchi K., Suda K., Suzuki H., Wakasugi M.,
Watanabe Y., Yokouchi S., Yano Y., and Yamada K.:“Operating experience with the RIKEN Radioactive Isotope Beam Factory”, Proceedings of the 2009 Particle
Accelerator Conference (PAC09), Vancouver, Canada,
2009–5, PAC09 Editor, Vancouver, pp. MO3GRI0-1–
MO3GRI0-5 (2009).

Publications
Publications[Journal](Original Papers) *Subject to Peer Review
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., Fukuda N.,
Kubono S., Motobayashi T., Nakabayashi T., Nakao T.,
Okumura T., Ong H., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Investigation into behavior of weakly-bound proton via
B(GT) measurement for the β decay of 24 Si”, AIP Conf.
Proc. 1165, 98–101 (2009).
Ichikawa Y., Kubo T., Aoi N., Naik V., ChakrabartiA., Fukuda N., Iwasaki H., Kubono S., Motobayashi
T., Nakabayashi T., Nakao T., Okumura T., Ong H.,
Onishi T., Suzuki D., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Betadecay study of Tz = −2 proton-rich nucleus 24 Si”, Eur.
Phys. J. A 42, 375–378 (2009).
Kikuchi S., Saito Y., Ryuto H., Fukunishi N., Abe T.,
Tanaka H., and Tsujimoto H.: “Eﬀects of heavy-ion
beams on chromosomes of common wheat, Triticum aestivum”, Muta. Res./Fund. Mol. Mech. Mutagen. 669,
63–66 (2009).
Takeuchi S., Aoi N., Motobayashi T., Ota S., TakeshitaE., Suzuki H., Baba H., Fukui T., Hashimoto Y., Ieki
K., Imai N., Iwasaki H., Kanno S., Kondo Y., Kubo T.,
Kurita K., Minemura T., Nakamura T., Okumura T.,
Onishi T., Sakurai H., Shimoura S., Sugou R., SuzukiD., Suzuki M., Takashina M., Tamaki M., Tanaka K.,
Togano Y., and Yamada K.: “Low-Iying States in 32Mg
studied by proton inelastic scattering”, Phys. Rev. C
79, No. 5, pp. 054319-1–054319-11 (2009).
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., Fukuda N.,
Kubono S., Motobayashi T., Nakabayashi T., Nakao T.,
Okumura T., Ong H., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Betadecay of the proton-rich nucleus 24 Si and its mirror
asymmetry”, Phys. Rev. C 80, 044302-1–044302-12(2009).
,
,
,
,
,
,
,
,
: “
”,
, No. 24, pp. 12–19 (2009).
[
Proc.]
Book• Proceedings(Review)
,
,
,
,
,
:
“
”,
132
188
,
, 2009–11,,, pp. 27–34 (2009).
(Others)
Fukunishi N., Fujimaki M., Watanabe T., Kumagai K.,
Komiyama M., Watanabe H., Goto A., Hasebe H.,

Oral Presentations
Oral Presentations((International) Conference etc.)
Fukunishi N., Fujimaki M., Watanabe T., Kumagai K.,
Komiyama M., Watanabe H., Goto A., Hasebe H.,
Higurashi Y., Ikezawa E., Kageyama T., Kamigaito
O., Kase M., Kuboki H., Kidera M., Nagase M., Maie
T., Nakagawa T., Ohnishi J., Okuno H., SakamotoN., Sekiguchi K., Suda K., Suzuki H., Wakasugi M.,
Watanabe Y., Yokouchi S., Yano Y., and Yamada K.:“Operating experience with the RIKEN Radioactive Isotope Beam Factory”, 23rd Particle Accelerator Conference (PAC09), Vancouver, Canada, May (2009).
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., Fukuda N.,
Kubono S., Motobayashi T., Nakabayashi T., Nakao T.,
Okumura T., Ong H., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Investigation into behavior of weakly-bound proton via
B(GT) measurement for the β decay of 24 Si”, International Conference on Nuclear Structure and Dynamics(NSD09), (University of Zagreb), Dubrovnik, Croatia,
May (2009).
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., Fukuda N.,
Kubono S., Motobayashi T., Nakabayashi T., Nakao T.,
Okumura T., Ong H., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Betadecay of 24 Si and mirror asymmetry of Gamow-Tellertransition strength”, 3rd Joint Meeting of the Nuclear
Physics Divisions of the APS and JPS (Hawaii 2009),
Hawaii, USA, Oct. (2009).
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., FukudaN., Kubono S., Motobayashi T., Nakabayashi T., Nakao
T., Okumura T., Ong H., Suzuki H., Suzuki M.,
Teranishi T., Yamada K., Yamaguchi H., and Sakurai
H.: “Gamow-Teller transition of proton-rich nucleus
24Si”, 7th Japan-China Joint Nuclear Physics Symposium, (University of Tsukuba), Tsukuba, Nov. (2009).
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., Fukuda N.,
Kubono S., Motobayashi T., Nakabayashi T., Nakao T.,
Okumura T., Ong H., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Mir-- 457 -

1

ror asymmetry for B(GT) of 24 Si induced by ThomasEhrman shift”, Tours Symposium on Nuclear Physics
and Astrophysics VII (TOURS 2009), (Konan University), Kobe, Nov. (2009).
(Domestic()Conference)
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
: “RI
”,
5
/ 33
,(
),
,8
(2008).
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
: “
(RILAC)
BT
”,
6
,(
),
,8
(2009).
,
,
,
,
,
,
,
,
: “
RIBF
RILAC2”,6,, 8 (2009).
,
,
,
,
: “
SQUID
”,
6
,(
),
,8
(2009).
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
: “RI
”,
6
,
,8
(2009).
,
,
,
,
,
,
,
,
,
,
: “
RIBF
”,
6
,(
),
,8
(2009).
,
,
,
,
,
,
,
,
: “
RIBF
”,
6
,(
),
, 8 (2009).
,
,
,
,
: “
EPICS
RI
”,
6
,(
),
,8
(2009).

- 458 -

2

RNC Technology Team
Cryogenic

Publications
Publications[Book • Proceedings
Proc.](Others)
Fukunishi N., Fujimaki M., Watanabe T., Kumagai K.,
Komiyama M., Watanabe H., Goto A., Hasebe H.,
Higurashi Y., Ikezawa E., Kageyama T., Kamigaito
O., Kase M., Kuboki H., Kidera M., Nagase M., Maie
T., Nakagawa T., Ohnishi J., Okuno H., SakamotoN., Sekiguchi K., Suda K., Suzuki H., Wakasugi M.,
Watanabe Y., Yokouchi S., Yano Y., and Yamada K.:“Operating experience with the RIKEN Radioactive Isotope Beam Factory”, Proceedings of the 2009 Particle
Accelerator Conference (PAC09), Vancouver, Canada,
2009–5, PAC09 Editor, Vancouver, pp. MO3GRI0-1–
MO3GRI0-5 (2009).

Oral Presentations
Oral Presentations((International) Conference etc.)
Fukunishi N., Fujimaki M., Watanabe T., Kumagai K.,
Komiyama M., Watanabe H., Goto A., Hasebe H.,
Higurashi Y., Ikezawa E., Kageyama T., Kamigaito
O., Kase M., Kuboki H., Kidera M., Nagase M., Maie
T., Nakagawa T., Ohnishi J., Okuno H., SakamotoN., Sekiguchi K., Suda K., Suzuki H., Wakasugi M.,
Watanabe Y., Yokouchi S., Yano Y., and Yamada K.:“Operating experience with the RIKEN Radioactive Isotope Beam Factory”, 23rd Particle Accelerator Conference (PAC09), Vancouver, Canada, May (2009).
((Domestic )Conference)
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
: “RI
”,
5
/ 33
,(
),
,8
(2008).
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
: “RI
”,
6
,
,8
(2009).

- 459 -

1

Instrumentation
Development GroupRNC

O., Kase M., Kuboki H., Kidera M., Nagase M., Maie
T., Nakagawa T., Ohnishi J., Okuno H., SakamotoN., Sekiguchi K., Suda K., Suzuki H., Wakasugi M.,
Watanabe Y., Yokouchi S., Yano Y., and Yamada K.:“Operating experience with the RIKEN Radioactive Isotope Beam Factory”, Proceedings of the 2009 Particle
Accelerator Conference (PAC09), Vancouver, Canada,
2009–5, PAC09 Editor, Vancouver, pp. MO3GRI0-1–
MO3GRI0-5 (2009).

Publications
Publications[Journal](Original Papers) *Subject to Peer Review
Nagae D., Asahi K., Ueno H., Kameda D., Takemura
M., Takase T., Yoshimi A., Sugimoto T., Nagatomo T.,
Kobayashi Y., Uchida M., Shimada K., Arai T., Inoue
T., Kagami S., and Hatakeyama N.: “Measurement ofElectric Quadrupole Moments for 31Al Using Spin Polarized RI Beams”, AIP Conf. Proc. 915, 853–856(2007).
Shimada K., Nagae D., Asahi K., Arai T., Takemura
M., Inoue T., Takase T., Kagami S., HatakeyamaN., Kobayashi Y., Ueno H., Yoshimi A., Kameda D.,
Nagatomo T., Sugimoto T., Kubono S., Yamaguchi H.,
Wakabayashi Y., Amadio G., Hayakawa S., Murata J.,
and Kawamura H.: “Production of Polarized Radioactive Beams via The Inverse-kinematics Reactions andTheir Applications”, AIP Conf. Proc. 915, 857–860(2007).
Asahi K., Ueno H., Shimada K., Nagatomo T., Yoshimi
A., Nagae D., Kameda D., Uchida M., Inoue T.,
Hatakeyama N., Kagami S., Hasama Y., Suzuki K.,
Murata J., Kawamura H., Narita K., and Ishihara M.:“Nuclear Structure Studies with Polarized Radioactive
Beams”, AIP Conf. Proc. 1149, 90–99 (2009).
Nagatomo T., Shimada K., Asahi K., Balabanski D. L.,
Daugas J., Depuydt M., De
Rydt M., Gaudefroy L.,
Grevy S., Hasama Y., Ichikawa Y., Kameda D., MorelP., Perrot L., Stodel C., Thomas J. C., VanderheijdenW., Vermeulen N., Vingerhoets P., Yoshimi A., Neyens
G., and Ueno H.: “Electric quadrupole moment of theneutron-rich 33 Al”, Eur. Phys. J. A 42, No. 3, pp.
383–385 (2009).
De Rydt M., Neyens G., Asahi K., Balabanski D. L.,
Daugas J., Depuydt M., Gaudefroy L., Grevy S.,
Hasama Y., Ichikawa Y., Morel P., Nagatomo T.,
Ohtsuka T., Perrot L., Shimada K., Stoedel C., ThomasJ., Ueno H., Utsuno Y., Wannes V., Vermeulen N.,
Vingerhoets P., and Yoshimi A.: “Precision measurement of the electric quadrupole moment of 31 Al anddetermination of the eﬀective proton charge in the sdshell”, Phys. Lett. B 678, 344–349 (2009).
De Rydt M., Balabanski D. L., Daugas J., Himpe P.,
Kameda D., Lozeva R., Morel P., Perrot L., Shimada
K., Stoedel C., Sugimoto T., Thomas J. C., Ueno H.,
Vermeulen N., Vingerhoets P., Yoshimi A., and Neyens
G.: “g factors of 17 N and 18 N remeasured”, Phys. Rev.
C 80, No. 3, pp. 037306-1–037306-4 (2009).
[Book • Proceedings
Proc.](Others)
Fukunishi N., Fujimaki M., Watanabe T., Kumagai K.,
Komiyama M., Watanabe H., Goto A., Hasebe H.,
Higurashi Y., Ikezawa E., Kageyama T., Kamigaito

Oral Presentations
Oral Presentations((International) Conference etc.)
Fukunishi N., Fujimaki M., Watanabe T., Kumagai K.,
Komiyama M., Watanabe H., Goto A., Hasebe H.,
Higurashi Y., Ikezawa E., Kageyama T., Kamigaito
O., Kase M., Kuboki H., Kidera M., Nagase M., Maie
T., Nakagawa T., Ohnishi J., Okuno H., SakamotoN., Sekiguchi K., Suda K., Suzuki H., Wakasugi M.,
Watanabe Y., Yokouchi S., Yano Y., and Yamada K.:“Operating experience with the RIKEN Radioactive Isotope Beam Factory”, 23rd Particle Accelerator Conference (PAC09), Vancouver, Canada, May (2009).
Ichikawa Y., Onisi T. K., Suzuki D., Iwasaki H., Kubo
T., Naik V., Chakrabarti A., Aoi N., Brown A. B.,
Fukuda N., Kubono S., Motobayashi T., Nakabayashi
T., Nakamura T., Nakao T., Okumura T., Ong H.,
Suzuki H., Suzuki M. K., Teranishi T., Yamaguchi H.,
and Sakurai H.: “Proton-rich nuclear structure investigated by β decay of 24 Si”, ICHOR-EFES International
Symposium on New Facet of Spin-Isospin Responses(SIR2010), (University of Tokyo), Tokyo, Feb. (2010).
Ichikawa Y., Onisi T. K., Suzuki D., Iwasaki H., Kubo
T., Naik V., Chakrabarti A., Aoi N., Brown A. B.,
Fukuda N., Kubono S., Motobayashi T., Nakabayashi
T., Nakamura T., Nakao T., Okumura T., Ong H.,
Suzuki H., Suzuki M. K., Teranishi T., Yamaguchi H.,
and Sakurai H.: “Mirror asymmetry investigated by βdecay of proton-rich 24 Si”, International Symposium
on Forefronts of Researches in Exotic Nuclear Structures (Niigata2010), (Niigata University), Toka-machi,
Niigata Pref., Mar. (2010).

- 460 -1

RNC

SLOWRI Team
Publications
Publications[Journal](Original Papers) *Subject to Peer Review
Takamine A., Wada M., Okada K., Nakamura T., Sonoda
T., Lioubimov V., Iimura H., Yamazaki Y., Kanai Y.,
Kojima T., Yoshida A., Kubo T., Katayama I., OhtaniS., Wollnik H., and Hans A. S.: “Isotope shift measurements of 11,9,7 Be+ ”, Eur. Phys. J. A, pp. 1–5 (2009).

Oral Presentations
Oral Presentations((International) Conference etc.)
Wada M.: “Precision laser spectroscopy of radioactive Be
isotopes and prospects for SLOWRI facility at RIKEN”,
8th International Workshop on APPLICATION OF
LASERS AND STORAGE DEVICES IN ATOMIC NUCLEI RESEARCH, (FLNR), Poznan, Poland, June(2009).
Sasaki A., Wakui T., Furukawa T., Kazato M., Wada M.,
Sonoda T., Takamine A., Kobayashi T., Nishimura M.,
Ueno H., Yoshimi A., Aoi N., Nishimura S., Togano Y.,
Takechi M., Kondo Y., Hatakeyama A., Matsuura Y.,
Kato Y., Odahara A., Shimoda T., Asahi K., ShinozukaT., Motobayashi T., and Matsuo Y.: “Fluorescence detection system for nuclear laser spectroscopy of Rb in
superﬂuid helium”, 3rd Joint Meeting of the Nuclear
Physics Divisions of the APS and JPS (Hawaii 2009),
Hawaii, USA, Oct. (2009).
((Domestic )Conference)
: “Be
”,
4
,(
),
, 12
(2007).

- 461 -1

RNC

Polarized RI Beam Team
Publications
Publications[]
Journal(Original Papers) *Subject to Peer Review
Nagae D., Asahi K., Ueno H., Kameda D., Takemura
M., Takase T., Yoshimi A., Sugimoto T., Nagatomo T.,
Kobayashi Y., Uchida M., Shimada K., Arai T., Inoue
T., Kagami S., and Hatakeyama N.: “Measurement ofElectric Quadrupole Moments for 31Al Using Spin Polarized RI Beams”, AIP Conf. Proc. 915, 853–856(2007).
Shimada K., Nagae D., Asahi K., Arai T., Takemura
M., Inoue T., Takase T., Kagami S., HatakeyamaN., Kobayashi Y., Ueno H., Yoshimi A., Kameda D.,
Nagatomo T., Sugimoto T., Kubono S., Yamaguchi H.,
Wakabayashi Y., Amadio G., Hayakawa S., Murata J.,
and Kawamura H.: “Production of Polarized Radioactive Beams via The Inverse-kinematics Reactions andTheir Applications”, AIP Conf. Proc. 915, 857–860(2007).
Ohnishi T., Kubo T., Kusaka K., Yoshida A., YoshidaK., Fukuda N., Ohtake M., Yanagisawa Y., Takeda H.,
Kameda D., Yamaguchi Y., Aoi N., Yoneda K., Otsu H.,
Takeuchi S., Sugimoto T., Kondo Y., Scheit H., Gono
Y., Sakurai H., Motobayashi T., Suzuki H., Nakao T.,
Kimura H., Mizoi Y., Matsushita M., Ieki K., Kuboki
T., Yamaguchi T., Suzuki T., Ozawa A., Moriguchi T.,
Yasuda Y., Nakamura T., Nannichi T., Shimamura T.,
Nakayama Y., Geissel H., Weick H., Nolen J. A., Tarasov
O. B., Nettleton A. S., Bazin D. P., Sherrill B. M.,
Morrissey D. J., and Mittig W.: “Identiﬁcation of New
Isotopes 125 Pd and 126 Pd Produced by In-Flight Fission of 345 MeV/nucleon 238 U: First Results from the
RIKEN RI Beam Factory”, J. Phys. Soc. Jpn. 77, No.
8, pp. 083201-1–083201-4 (2008).
Asahi K., Ueno H., Shimada K., Nagatomo T., Yoshimi
A., Nagae D., Kameda D., Uchida M., Inoue T.,
Hatakeyama N., Kagami S., Hasama Y., Suzuki K.,
Murata J., Kawamura H., Narita K., and Ishihara M.:“Nuclear Structure Studies with Polarized Radioactive
Beams”, AIP Conf. Proc. 1149, 90–99 (2009).
Yoshimi A., Asahi K., Inoue T., Uchida M., HatakeyamaN., Tsuchiya M., and Kagami S.: “Nuclear Spin Maser
at Highly Stabilized Low Magnetic Field and Search for
Atomic EDM”, AIP Conf. Proc. 1149, 249–252 (2009).
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., Fukuda N.,
Kubono S., Motobayashi T., Nakabayashi T., Nakao T.,
Okumura T., Ong H., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Investigation into behavior of weakly-bound proton via
B(GT) measurement for the β decay of 24 Si”, AIP Conf.
Proc. 1165, 98–101 (2009).

Nagatomo T., Shimada K., Asahi K., Balabanski D. L.,
Daugas J., Depuydt M., De
Rydt M., Gaudefroy L.,
Grevy S., Hasama Y., Ichikawa Y., Kameda D., MorelP., Perrot L., Stodel C., Thomas J. C., VanderheijdenW., Vermeulen N., Vingerhoets P., Yoshimi A., Neyens
G., and Ueno H.: “Electric quadrupole moment of theneutron-rich 33 Al”, Eur. Phys. J. A 42, No. 3, pp.
383–385 (2009).
Ichikawa Y., Kubo T., Aoi N., Naik V., ChakrabartiA., Fukuda N., Iwasaki H., Kubono S., Motobayashi
T., Nakabayashi T., Nakao T., Okumura T., Ong H.,
Onishi T., Suzuki D., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Betadecay study of Tz = −2 proton-rich nucleus 24 Si”, Eur.
Phys. J. A 42, 375–378 (2009).
Hata M., Akiyama T., Ikeda Y., Kawamura H., Narota
K., Ninomiya K., Ogawa N., Sato T., Seitaibashi E.,
Sekiguchi Y., Tsutsui R., Yazawa K., and Murata J.:“Recent results on short-range gravity experiment”, J.
Phys.: Con. Ser. 189, 012019-01–012019-10 (2009).
Ninomiya K., Akiyama T., Hata M., Ikeda Y., Kawamura
H., Narota K., Ogawa N., Sato T., Seitaibashi E.,
Sekiguchi Y., Tsutsui R., Yazawa K., and Murata J.:“New experimental technique for short-range gravity
measurement”, J. Phys.: Con. Ser. 189, 012026-1–
012026-7 (2009).
De Rydt M., Neyens G., Asahi K., Balabanski D. L.,
Daugas J., Depuydt M., Gaudefroy L., Grevy S.,
Hasama Y., Ichikawa Y., Morel P., Nagatomo T.,
Ohtsuka T., Perrot L., Shimada K., Stoedel C., ThomasJ., Ueno H., Utsuno Y., Wannes V., Vermeulen N.,
Vingerhoets P., and Yoshimi A.: “Precision measurement of the electric quadrupole moment of 31 Al anddetermination of the eﬀective proton charge in the sdshell”, Phys. Lett. B 678, 344–349 (2009).
De Rydt M., Balabanski D. L., Daugas J., Himpe P.,
Kameda D., Lozeva R., Morel P., Perrot L., Shimada
K., Stoedel C., Sugimoto T., Thomas J. C., Ueno H.,
Vermeulen N., Vingerhoets P., Yoshimi A., and Neyens
G.: “g factors of 17 N and 18 N remeasured”, Phys. Rev.
C 80, No. 3, pp. 037306-1–037306-4 (2009).
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., Fukuda N.,
Kubono S., Motobayashi T., Nakabayashi T., Nakao T.,
Okumura T., Ong H., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Betadecay of the proton-rich nucleus 24 Si and its mirror
asymmetry”, Phys. Rev. C 80, 044302-1–044302-12(2009).
Katayama N., Uchida M., Hashizume D., Niitaka S.,
Matsuno J., Matsumura D., Nishihata Y., Mizuki J.,
Takeshita N., Guazzi A., Nohara M., and Takagi H.:“Anomalous Metallic State in the Vicinity of Metal
to Valence-Bond Solid Insulator Transition in LiVS2 ”,
Phys. Rev. Lett. 103, 146405-1–146405-4 (2009).

- 462 -1

(Others)
Murata J., Akiyama T., Hata M., Hirayama Y., Ikeda
Y., Ishii T., Kameda D., Kawamura H., Mitsuoka
S., Miyatake H., Nagae D., Ninomiya K., Nitta M.,
Seitaibashi E., and Toyoda T.: “Test of time reversal
symmetry using polarized nuclei”, JAEA-Review 2009036, 62–63 (2009).
Oral Presentations
Oral Presentations((International) Conference etc.)
Ooe K., Yahagi W., Komori Y., Fujisawa H., Kikunaga
H., Yoshimura T., Sato W., Takahashi N., Takahisa
K., Haba H., Kudou Y., Ezaki Y., and Shinohara A.:“Studies of Extraction Behavior of Tungsten toward Solution Chemistry of Seaborgium (Element 106)”, International Workshop on Molecular Information and Dynamics 2008, (Osaka University Global COE Program ),Taipei, Taiwan, Nov. (2008).
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., Fukuda N.,
Kubono S., Motobayashi T., Nakabayashi T., Nakao T.,
Okumura T., Ong H., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Investigation into behavior of weakly-bound proton via
B(GT) measurement for the β decay of 24 Si”, International Conference on Nuclear Structure and Dynamics(NSD09), (University of Zagreb), Dubrovnik, Croatia,
May (2009).
Furukawa T., Hatakeyama A., Fujikake K., Matsuura Y.,
Kobayashi T., Shimoda T., and Matsuo Y.: “Precision
Laser Spectroscopy of Alkaline and Alkaline-like Atoms
in Superﬂuid Helium”, 19th International Conferenceon Laser Spectroscopy (ICOLS2009), Kussharo, June(2009).
Ueno H.: “Nuclear moments of neutron-rich aluminium
isotopes”, Gordon Research Conference on Nuclear
Chemistry, New London, USA, June–June (2009).
Ueno H.: “Electromagnetic moments of exotic nuclei”, Advanced Studies Institute: Symmetries and Spin (SPINPraha-2009), (Charles University in Prague), Prague,
Czech, July–Aug. (2009).
Inoue T.: “A 129 Xe active spin maser with digitalized feedback”, 3rd Joint Meeting of the Nuclear Physics Divisions of the APS and JPS (Hawaii 2009), Hawaii, USA,
Oct. (2009).
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., Fukuda N.,
Kubono S., Motobayashi T., Nakabayashi T., Nakao T.,
Okumura T., Ong H., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Betadecay of 24 Si and mirror asymmetry of Gamow-Tellertransition strength”, 3rd Joint Meeting of the Nuclear
Physics Divisions of the APS and JPS (Hawaii 2009),
Hawaii, USA, Oct. (2009).
Yoshimi A.: “Development of Rb atomic magnetometer

for EDM experiment with 129 Xe spin maser”, 3rd Joint
Meeting of the Nuclear Physics Divisions of the APS and
JPS (Hawaii 2009), Hawaii, USA, Oct. (2009).
Sasaki A., Wakui T., Furukawa T., Kazato M., Wada M.,
Sonoda T., Takamine A., Kobayashi T., Nishimura M.,
Ueno H., Yoshimi A., Aoi N., Nishimura S., Togano Y.,
Takechi M., Kondo Y., Hatakeyama A., Matsuura Y.,
Kato Y., Odahara A., Shimoda T., Asahi K., ShinozukaT., Motobayashi T., and Matsuo Y.: “Fluorescence detection system for nuclear laser spectroscopy of Rb in
superﬂuid helium”, 3rd Joint Meeting of the Nuclear
Physics Divisions of the APS and JPS (Hawaii 2009),
Hawaii, USA, Oct. (2009).
Suzuki K.: “Observation of stress eﬀect on iron diﬀusion in
Si by Mössbauer spectroscopy”, 3rd Joint Meeting of the
Nuclear Physics Divisions of the APS and JPS (Hawaii2009), Hawaii, USA, Oct. (2009).
Ueno H., Yoshimi A., and Asahi K.: “RIPS upgrade andphysics programs”, 3rd Joint Meeting of the Nuclear
Physics Divisions of the APS and JPS (Hawaii 2009),
Hawaii, USA, Oct. (2009).
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., FukudaN., Kubono S., Motobayashi T., Nakabayashi T., Nakao
T., Okumura T., Ong H., Suzuki H., Suzuki M.,
Teranishi T., Yamada K., Yamaguchi H., and Sakurai
H.: “Gamow-Teller transition of proton-rich nucleus
24Si”, 7th Japan-China Joint Nuclear Physics Symposium, (University of Tsukuba), Tsukuba, Nov. (2009).
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., Fukuda N.,
Kubono S., Motobayashi T., Nakabayashi T., Nakao T.,
Okumura T., Ong H., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Mirror asymmetry for B(GT) of 24 Si induced by ThomasEhrman shift”, Tours Symposium on Nuclear Physics
and Astrophysics VII (TOURS 2009), (Konan University), Kobe, Nov. (2009).
Yoshimi A.: “Structures of neutron-rich Si, S and P isotopes studied from electromagnetic moments”, International Workshop on Physics of Nuclei at Extreme,(Tokyo Institute of Technology), Tokyo, Jan. (2010).
Inoue T.: “Ultrahigh precision observation of nuclear spin
precession and application to EDM measurement”, International Workshop on Physics of Nuclei at Extreme,(Tokyo Institute of Technology), Tokyo, Jan. (2010).
((Domestic)Conference)
,
,
,
: “
[(R)-3]
”,
8
GSC
,(
),
, 3 (2008).
,
,
,
,
,
,
,
,
,
,
,
,
: “

- 463 -

2

(I)”,
3(2009).
,
,
,

64

,

,

8

Li
,

,

,
: “
(II)”,, 3 (2009).
,
,
: “

,

,
,

,
,

,

,
,

,

64

,

,

,3
,

,

,

,

,

,
,

”,
6
,6
(2009).
EDM
Fundamental Physics Uing),
, 8 (2009).
,
,
,
,
: “
57
Mn
S/N
”, 200953,(),,9(2009).
,
,
,
,
,
,
,
,
: “
57
Mn
”, 200953,(),, 9 (2009).
,
,
,
,
,
,
,
,
: “
57
Mn
”, 200953,(),, 9 (2009).
,
,
,
,
,
,
: “
Au
”,
2009
,
, 9 (2009).
,
,
,
,
,
,
,
,
: “
57
Mn
S/N
”,
21
II
,
, 12
(2009).
: “RIKEN nuclear-moment measurements: Current researches and perspectives”, Workshop on exotic
nuclei and modern shell models, (),,2(2010).
,
,
,
,
,
,
: “Au
”,
65
,
, 3 (2010).
, Behr J. A.,,, Levy P.,,,, Pearson M.,,
8: “TRIUMF-ISAC
Li
”,
65
,
, 3 (2010).
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
: “KEK-TRIAC
AMO,: “129Xe”,
Atoms , (,,,,- 464 -

,
,

,
,

”,
(2010).
,
,
,
: “
2”,
65
(2010).
, Behr J. A.,,,, Levy P.,
,
,
,
,
,
,
, Pearson M.,
,
8
: “
Li
”,
6
,
,3
(2010).
,
,
,
,
57
,
: “
Mn
”,
11
,
, 3 (2010).
,3
,
,

65
,

,
,
,

,

3

RNC

Rare RI-ring Team
Publications
Publications[Journal](Original Papers) *Subject to Peer Review
Nagae D., Asahi K., Ueno H., Kameda D., Takemura
M., Takase T., Yoshimi A., Sugimoto T., Nagatomo T.,
Kobayashi Y., Uchida M., Shimada K., Arai T., Inoue
T., Kagami S., and Hatakeyama N.: “Measurement ofElectric Quadrupole Moments for 31Al Using Spin Polarized RI Beams”, AIP Conf. Proc. 915, 853–856(2007).
Shimada K., Nagae D., Asahi K., Arai T., Takemura
M., Inoue T., Takase T., Kagami S., HatakeyamaN., Kobayashi Y., Ueno H., Yoshimi A., Kameda D.,
Nagatomo T., Sugimoto T., Kubono S., Yamaguchi H.,
Wakabayashi Y., Amadio G., Hayakawa S., Murata J.,
and Kawamura H.: “Production of Polarized Radioactive Beams via The Inverse-kinematics Reactions andTheir Applications”, AIP Conf. Proc. 915, 857–860(2007).
Ohnishi T., Kubo T., Kusaka K., Yoshida A., YoshidaK., Fukuda N., Ohtake M., Yanagisawa Y., Takeda H.,
Kameda D., Yamaguchi Y., Aoi N., Yoneda K., Otsu H.,
Takeuchi S., Sugimoto T., Kondo Y., Scheit H., Gono
Y., Sakurai H., Motobayashi T., Suzuki H., Nakao T.,
Kimura H., Mizoi Y., Matsushita M., Ieki K., Kuboki
T., Yamaguchi T., Suzuki T., Ozawa A., Moriguchi T.,
Yasuda Y., Nakamura T., Nannichi T., Shimamura T.,
Nakayama Y., Geissel H., Weick H., Nolen J. A., Tarasov
O. B., Nettleton A. S., Bazin D. P., Sherrill B. M.,
Morrissey D. J., and Mittig W.: “Identiﬁcation of New
Isotopes 125 Pd and 126 Pd Produced by In-Flight Fission of 345 MeV/nucleon 238 U: First Results from the
RIKEN RI Beam Factory”, J. Phys. Soc. Jpn. 77, No.
8, pp. 083201-1–083201-4 (2008).

- 465 -1RNC

SCRIT Team
Publications
Publications[Journal](Original Papers) *Subject to Peer Review
Suda T., Wakasugi M., Emoto T., Ito S., Kurita K., Tamae
T., Wang S., and Yano Y.: “First demonstration of electron scattering using a novel target developed for shortlived nuclei”, Phys. Rev. Lett. 102, No. 10, pp. 1025011–102501-4 (2009).

- 466 -

1

Research Instruments Group
RNC
Publications
Publications[Journal](Original Papers) *Subject to Peer Review
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., Fukuda N.,
Kubono S., Motobayashi T., Nakabayashi T., Nakao T.,
Okumura T., Ong H., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Investigation into behavior of weakly-bound proton via
B(GT) measurement for the β decay of 24 Si”, AIP Conf.
Proc. 1165, 98–101 (2009).
Ichikawa Y., Kubo T., Aoi N., Naik V., ChakrabartiA., Fukuda N., Iwasaki H., Kubono S., Motobayashi
T., Nakabayashi T., Nakao T., Okumura T., Ong H.,
Onishi T., Suzuki D., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Betadecay study of Tz = −2 proton-rich nucleus 24 Si”, Eur.
Phys. J. A 42, 375–378 (2009).
Takeuchi S., Aoi N., Motobayashi T., Ota S., TakeshitaE., Suzuki H., Baba H., Fukui T., Hashimoto Y., Ieki
K., Imai N., Iwasaki H., Kanno S., Kondo Y., Kubo T.,
Kurita K., Minemura T., Nakamura T., Okumura T.,
Onishi T., Sakurai H., Shimoura S., Sugou R., SuzukiD., Suzuki M., Takashina M., Tamaki M., Tanaka K.,
Togano Y., and Yamada K.: “Low-Iying States in 32Mg
studied by proton inelastic scattering”, Phys. Rev. C
79, No. 5, pp. 054319-1–054319-11 (2009).
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., Fukuda N.,
Kubono S., Motobayashi T., Nakabayashi T., Nakao T.,
Okumura T., Ong H., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Betadecay of the proton-rich nucleus 24 Si and its mirror
asymmetry”, Phys. Rev. C 80, 044302-1–044302-12(2009).

decay of 24 Si and mirror asymmetry of Gamow-Tellertransition strength”, 3rd Joint Meeting of the Nuclear
Physics Divisions of the APS and JPS (Hawaii 2009),
Hawaii, USA, Oct. (2009).
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., FukudaN., Kubono S., Motobayashi T., Nakabayashi T., Nakao
T., Okumura T., Ong H., Suzuki H., Suzuki M.,
Teranishi T., Yamada K., Yamaguchi H., and Sakurai
H.: “Gamow-Teller transition of proton-rich nucleus
24Si”, 7th Japan-China Joint Nuclear Physics Symposium, (University of Tsukuba), Tsukuba, Nov. (2009).
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., Fukuda N.,
Kubono S., Motobayashi T., Nakabayashi T., Nakao T.,
Okumura T., Ong H., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Mirror asymmetry for B(GT) of 24 Si induced by ThomasEhrman shift”, Tours Symposium on Nuclear Physics
and Astrophysics VII (TOURS 2009), (Konan University), Kobe, Nov. (2009).

Oral Presentations
Oral Presentations((International) Conference etc.)
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., Fukuda N.,
Kubono S., Motobayashi T., Nakabayashi T., Nakao T.,
Okumura T., Ong H., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Investigation into behavior of weakly-bound proton via
B(GT) measurement for the β decay of 24 Si”, International Conference on Nuclear Structure and Dynamics(NSD09), (University of Zagreb), Dubrovnik, Croatia,
May (2009).
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., Fukuda N.,
Kubono S., Motobayashi T., Nakabayashi T., Nakao T.,
Okumura T., Ong H., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Beta- 467 -1RNC

GARIS Team
Publications
Publications

Journal[](Original Papers) *Subject to Peer Review
Haba H., Kaji D., Komori Y., Kudou Y., Morimoto K.,
Morita K., Ooe K., Ohzeki K., Sato N., Shinohara A.,
and Yoneda A.: “RIKEN Gas-ﬁlled Recoil Ion Separator (GARIS) as a promising interface for superheavy element chemistry : Production of element 104, 261Rf,
using the GARIS/gas-jet system”, Chem. Lett. 38, No.
5, pp. 426–427 (2009).
(Others)
Asai M., Tsukada K., Kasamatsu Y., Sato T., ToyoshimaA., Ishii Y., Takahashi R., Nagame Y., Ishii T.,
Nishinaka I., Kaji D., Morimoto K., and Kojima Y.:“Alpha-gamma spectroscopy of 259 Rf produced by using a mixed Cf target”, JAEA-Review 2009, No. 036,
pp. 37–38 (2009).

- 468 -1

RNC

BigRIPS Team
Publications
Publications

Journal[](Original Papers) *Subject to Peer Review
Ariyoshi S., Taino T., Dobroiu A., Sato H., Matsuo H.,
and Otani C.: “Terahertz Detector based on a Superconducting Tunnel Junction Coupled to a Thin Superconductor Film”, Appl. Phys. Lett. 95, No. 19, pp.
193504-1–193504-3 (2009).
[
Proc.]
Book• Proceedings(Original Papers) *Subject to Peer Review
Ariyoshi S., Taino T., Dobroiu A., Sato H., Matsuo H.,
and Otani C.: “Design of a Terahertz Detector based on
a Superconducting Tunnel Junction Coupled to a Thin
Superconductor Film”, Proceedings of the 34th International Conference on Infrared, Millimeter, and Terahertz Wave (IRMMW-THz 2009), Busan, Korea, 2009–
9, IRMMW-THz 2009, Busan, p. T5E06.0372 (2009).
(Others)
Ariyoshi S., Otani C., Dobroiu A., Sato H., Taino T.,
Matsuo H., and Shimizu H.: “Two-dimensional Superconducting Detector Array for Terahertz Imaging Applications”, Extended Abstracts of 12th International Superconductive Electronics Conference, Fukuoka, 2009–6,
ISEC 2009, Fukuoka, pp. MD-P35-1–MD-P35-2 (2009).
Oral Presentations
Oral Presentations() Conference etc.)(International
Ariyoshi S., Otani C., Dobroiu A., Sato H., Taino T.,
Matsuo H., and Shimizu H.: “Two-dimensional Superconducting Detector Array for Terahertz Imaging Applications”, International Superconductive Electronics
Conference (ISEC 2009), Fukuoka, June (2009).
Ariyoshi S., Taino T., Dobroiu A., Sato H., Matsuo H.,
and Otani C.: “Design of a Terahertz Detector based on
a Superconducting Tunnel Junction Coupled to a Thin
Superconductor Film”, 34th International Conference on
Infrared, Millimeter, and Terahertz Waves (IRMMWTHz 2009), Busan, Korea, Sept. (2009).
Ariyoshi S., Taino T., Dobroiu A., Sato H., Matsuo H.,
and Otani C.: “Evaluation of a Terahertz-wave Detector
with a Superconducting Tunnel Junction Coupled to aThin Superconductor Film”, 2009 East Asia Symposiumon Superconductor Electronics (EASSE2009), Nanjing,
China, Oct. (2009).

- 469 -1

RNC

SAMURAI Team
Publications
Publications[]
Journal(Original Papers) *Subject to Peer Review
Nagae D., Asahi K., Ueno H., Kameda D., Takemura
M., Takase T., Yoshimi A., Sugimoto T., Nagatomo T.,
Kobayashi Y., Uchida M., Shimada K., Arai T., Inoue
T., Kagami S., and Hatakeyama N.: “Measurement ofElectric Quadrupole Moments for 31Al Using Spin Polarized RI Beams”, AIP Conf. Proc. 915, 853–856(2007).
Shimada K., Nagae D., Asahi K., Arai T., Takemura
M., Inoue T., Takase T., Kagami S., HatakeyamaN., Kobayashi Y., Ueno H., Yoshimi A., Kameda D.,
Nagatomo T., Sugimoto T., Kubono S., Yamaguchi H.,
Wakabayashi Y., Amadio G., Hayakawa S., Murata J.,
and Kawamura H.: “Production of Polarized Radioactive Beams via The Inverse-kinematics Reactions andTheir Applications”, AIP Conf. Proc. 915, 857–860(2007).
Ohnishi T., Kubo T., Kusaka K., Yoshida A., YoshidaK., Fukuda N., Ohtake M., Yanagisawa Y., Takeda H.,
Kameda D., Yamaguchi Y., Aoi N., Yoneda K., Otsu H.,
Takeuchi S., Sugimoto T., Kondo Y., Scheit H., Gono
Y., Sakurai H., Motobayashi T., Suzuki H., Nakao T.,
Kimura H., Mizoi Y., Matsushita M., Ieki K., Kuboki
T., Yamaguchi T., Suzuki T., Ozawa A., Moriguchi T.,
Yasuda Y., Nakamura T., Nannichi T., Shimamura T.,
Nakayama Y., Geissel H., Weick H., Nolen J. A., Tarasov
O. B., Nettleton A. S., Bazin D. P., Sherrill B. M.,
Morrissey D. J., and Mittig W.: “Identiﬁcation of New
Isotopes 125 Pd and 126 Pd Produced by In-Flight Fission of 345 MeV/nucleon 238 U: First Results from the
RIKEN RI Beam Factory”, J. Phys. Soc. Jpn. 77, No.
8, pp. 083201-1–083201-4 (2008).
Asahi K., Ueno H., Shimada K., Nagatomo T., Yoshimi
A., Nagae D., Kameda D., Uchida M., Inoue T.,
Hatakeyama N., Kagami S., Hasama Y., Suzuki K.,
Murata J., Kawamura H., Narita K., and Ishihara M.:“Nuclear Structure Studies with Polarized Radioactive
Beams”, AIP Conf. Proc. 1149, 90–99 (2009).
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., Fukuda N.,
Kubono S., Motobayashi T., Nakabayashi T., Nakao T.,
Okumura T., Ong H., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Investigation into behavior of weakly-bound proton via
B(GT) measurement for the β decay of 24 Si”, AIP Conf.
Proc. 1165, 98–101 (2009).
Nagatomo T., Shimada K., Asahi K., Balabanski D. L.,
Daugas J., Depuydt M., De
Rydt M., Gaudefroy L.,
Grevy S., Hasama Y., Ichikawa Y., Kameda D., MorelP., Perrot L., Stodel C., Thomas J. C., VanderheijdenW., Vermeulen N., Vingerhoets P., Yoshimi A., Neyens

G., and Ueno H.: “Electric quadrupole moment of theneutron-rich 33 Al”, Eur. Phys. J. A 42, No. 3, pp.
383–385 (2009).
Ichikawa Y., Kubo T., Aoi N., Naik V., ChakrabartiA., Fukuda N., Iwasaki H., Kubono S., Motobayashi
T., Nakabayashi T., Nakao T., Okumura T., Ong H.,
Onishi T., Suzuki D., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Betadecay study of Tz = −2 proton-rich nucleus 24 Si”, Eur.
Phys. J. A 42, 375–378 (2009).
Takamine A., Wada M., Okada K., Nakamura T., Sonoda
T., Lioubimov V., Iimura H., Yamazaki Y., Kanai Y.,
Kojima T., Yoshida A., Kubo T., Katayama I., OhtaniS., Wollnik H., and Hans A. S.: “Isotope shift measurements of 11,9,7 Be+ ”, Eur. Phys. J. A, pp. 1–5 (2009).
Takeuchi S., Aoi N., Motobayashi T., Ota S., TakeshitaE., Suzuki H., Baba H., Fukui T., Hashimoto Y., Ieki
K., Imai N., Iwasaki H., Kanno S., Kondo Y., Kubo T.,
Kurita K., Minemura T., Nakamura T., Okumura T.,
Onishi T., Sakurai H., Shimoura S., Sugou R., SuzukiD., Suzuki M., Takashina M., Tamaki M., Tanaka K.,
Togano Y., and Yamada K.: “Low-Iying States in 32Mg
studied by proton inelastic scattering”, Phys. Rev. C
79, No. 5, pp. 054319-1–054319-11 (2009).
De Rydt M., Balabanski D. L., Daugas J., Himpe P.,
Kameda D., Lozeva R., Morel P., Perrot L., Shimada
K., Stoedel C., Sugimoto T., Thomas J. C., Ueno H.,
Vermeulen N., Vingerhoets P., Yoshimi A., and Neyens
G.: “g factors of 17 N and 18 N remeasured”, Phys. Rev.
C 80, No. 3, pp. 037306-1–037306-4 (2009).
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., Fukuda N.,
Kubono S., Motobayashi T., Nakabayashi T., Nakao T.,
Okumura T., Ong H., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Betadecay of the proton-rich nucleus 24 Si and its mirror
asymmetry”, Phys. Rev. C 80, 044302-1–044302-12(2009).
(Others)
Murata J., Akiyama T., Hata M., Hirayama Y., Ikeda
Y., Ishii T., Kameda D., Kawamura H., Mitsuoka
S., Miyatake H., Nagae D., Ninomiya K., Nitta M.,
Seitaibashi E., and Toyoda T.: “Test of time reversal
symmetry using polarized nuclei”, JAEA-Review 2009036, 62–63 (2009).

Oral Presentations
Oral Presentations()Conference etc.)(International
Ohnishi T., Kubo T., Kusaka K., Yoshida A., YoshidaK., Fukuda N., Yanagisawa Y., Ohtake M., Takeda
H., and Kameda D.: “BigRIPS Commissioning Experiment”, Third experts meeting on critical issues of nextgeneration high-intensity In-ﬂight separators, (National
Superconducting Cyclotron Laboratory, Michigan State- 470 -

1

University), East Lansing, USA, Mar.–Apr. (2008).
Yoshida A.: “BigRIPS target system”, Third experts
meeting on critical issues of next-generation highintensity In-ﬂight separators, (MSU, NSCL), East Lansing, USA, Mar.–Apr. (2008).
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., Fukuda N.,
Kubono S., Motobayashi T., Nakabayashi T., Nakao T.,
Okumura T., Ong H., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Investigation into behavior of weakly-bound proton via
B(GT) measurement for the β decay of 24 Si”, International Conference on Nuclear Structure and Dynamics(NSD09), (University of Zagreb), Dubrovnik, Croatia,
May (2009).
Uwamino Y., Mukai H., Higurashi R., Akashio A., Fukuda
H., Sakamoto H., Yoshida A., and Yoshida K.: “Dosimetry around BigRIPS at RIKEN RIBF”, 11th Neutron
and Ion Dosimetry Symposium, (iThemba Laboratory
for Accelerator-Based Sciences), Cape Town, South
Africa, Oct. (2009).
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., Fukuda N.,
Kubono S., Motobayashi T., Nakabayashi T., Nakao T.,
Okumura T., Ong H., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Betadecay of 24 Si and mirror asymmetry of Gamow-Tellertransition strength”, 3rd Joint Meeting of the Nuclear
Physics Divisions of the APS and JPS (Hawaii 2009),
Hawaii, USA, Oct. (2009).
Baba H., Ichihara T., Ohnishi T., Takeuchi S., YoshidaK., Watanabe Y., Ota S., and Shimoura S.: “The New
DAQ System in RIKEN RIBF”, 3rd Joint Meeting of the
Nuclear Physics Divisions of the APS and JPS (Hawaii2009), Hawaii, USA, Oct. (2009).
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., FukudaN., Kubono S., Motobayashi T., Nakabayashi T., Nakao
T., Okumura T., Ong H., Suzuki H., Suzuki M.,
Teranishi T., Yamada K., Yamaguchi H., and Sakurai
H.: “Gamow-Teller transition of proton-rich nucleus
24Si”, 7th Japan-China Joint Nuclear Physics Symposium, (University of Tsukuba), Tsukuba, Nov. (2009).
Ichikawa Y., Onishi T., Suzuki D., Iwasaki H., Naik V.,
Kubo T., Chakrabarti A., Aoi N., Brown A., Fukuda N.,
Kubono S., Motobayashi T., Nakabayashi T., Nakao T.,
Okumura T., Ong H., Suzuki H., Suzuki M., TeranishiT., Yamada K., Yamaguchi H., and Sakurai H.: “Mirror asymmetry for B(GT) of 24 Si induced by ThomasEhrman shift”, Tours Symposium on Nuclear Physics
and Astrophysics VII (TOURS 2009), (Konan University), Kobe, Nov. (2009).
Ichikawa Y., Onisi T. K., Suzuki D., Iwasaki H., Kubo
T., Naik V., Chakrabarti A., Aoi N., Brown A. B.,
Fukuda N., Kubono S., Motobayashi T., Nakabayashi

T., Nakamura T., Nakao T., Okumura T., Ong H.,
Suzuki H., Suzuki M. K., Teranishi T., Yamaguchi H.,
and Sakurai H.: “Proton-rich nuclear structure investigated by β decay of 24 Si”, ICHOR-EFES International
Symposium on New Facet of Spin-Isospin Responses(SIR2010), (University of Tokyo), Tokyo, Feb. (2010).
Ichikawa Y., Onisi T. K., Suzuki D., Iwasaki H., Kubo
T., Naik V., Chakrabarti A., Aoi N., Brown A. B.,
Fukuda N., Kubono S., Motobayashi T., Nakabayashi
T., Nakamura T., Nakao T., Okumura T., Ong H.,
Suzuki H., Suzuki M. K., Teranishi T., Yamaguchi H.,
and Sakurai H.: “Mirror asymmetry investigated by βdecay of proton-rich 24 Si”, International Symposium
on Forefronts of Researches in Exotic Nuclear Structures (Niigata2010), (Niigata University), Toka-machi,
Niigata Pref., Mar. (2010).
()Conference)(Domestic
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
, Beer G.
, Choi S.,,, Buehler P., Hirtl
A.,A., Cargnelli M., Kienle P., Marton J., Widmann E.,
Zmeskal J., Curceanu C. O., Guaraldo C., Iliescu M.,
Pietreanu D., Sirghi D., Sirghi F., Faso D., Busso L.,
Morra O.: “K
3
”,
2007
,
,
3 (2007).
,
,
,
,
,
,
Schury P. H., Lioubimov V.,
,
,
,
,
,
,
, Wollnik H.,
Hans A. S.: “
Be
”,
2008
,
,
9 (2008).
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
, Beer G. A.,, Choi,, Buehler P., Cargnelli M., Hirtl A.,S.,
Kienle P., Marton J., Widmann E., Zmeskal J.,,
Curceanu C. O., Guaraldo C., Iliescu M., Pietreanu D.,
Sirghi D., Sirghi F., Faso D., Morra O., Busso L.: “K
3
III”,
2008
,
, 9 (2008).
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
: “KEK-TRIAC
8
Li
”,
65
,
, 3 (2010).
,, Behr J. A.,,,,,, Levy P.,,,- 471 -

2

,

,
,
,

,
,
, Pearson M.,
8
: “
Li
”,
6
,
, 3 (2010).

,
,

,
,

- 472 -

3

Computing
and Network Team
RNC
Publications
Publications[]
Journal(Original Papers) *Subject to Peer Review
Takeuchi S., Aoi N., Motobayashi T., Ota S., TakeshitaE., Suzuki H., Baba H., Fukui T., Hashimoto Y., Ieki
K., Imai N., Iwasaki H., Kanno S., Kondo Y., Kubo T.,
Kurita K., Minemura T., Nakamura T., Okumura T.,
Onishi T., Sakurai H., Shimoura S., Sugou R., SuzukiD., Suzuki M., Takashina M., Tamaki M., Tanaka K.,
Togano Y., and Yamada K.: “Low-Iying States in 32Mg
studied by proton inelastic scattering”, Phys. Rev. C
79, No. 5, pp. 054319-1–054319-11 (2009).

Oral Presentations
Oral Presentations(International() Conference etc.)
Baba H., Ichihara T., Ohnishi T., Takeuchi S., YoshidaK., Watanabe Y., Ota S., and Shimoura S.: “The New
DAQ System in RIKEN RIBF”, 3rd Joint Meeting of the
Nuclear Physics Divisions of the APS and JPS (Hawaii2009), Hawaii, USA, Oct. (2009).

- 473 -

1

Accelerator
Applications Research Group
RNC
Publications
Publications[]
Journal(Original Papers) *Subject to Peer Review
Ishii K., Sugiyama R., Onuki M., Kazama Y., Matsunaga
S., and Kawano S.: “The Y chromosome-speciﬁc STS
marker MS2 and its peripheral regions on the Y chromosome of the dioecious plant Silene latifolia”, Genome
51, No. 4, pp. 251–260 (2008).
Kazama Y., Fujiwara M., Koizumi A., Nishihara K.,
Kifune E., Abe T., and Kawano S.: “A SUPERMANlike gene is exclusively expressed in female ﬂowers of the
dioecious plant Silene latifolia”, Plant Cell Physiol. 50,
No. 6, pp. 1127–1141 (2009).
(Review),: “”, Plant. Morphol. 21, No. 1, pp. 71–77 (2009).
,
: “
( )
( )
”,
63,
No. 3, pp. 42–47 (2009).

Oral Presentations
Oral Presentations() Conference etc.)(International
Kazama Y., Liu Y., Hirano T., Ohbu S., Hayashi Y.,
Matsuyama T., and Abe T.: “The powerful technology
for inducing deletion mutations in Arabidopsis thaliana”,
Plant Biology 2009: Joint Annual Meetings of the American Society of Plant Biologists and the Phycological Society of America, (American Society of Plant Biologist),
Honolulu, USA, July (2009).
()Conference)(Domestic
,
,
,
,
,
,
,
: “
”,
50
,
, 3 (2009).
,
,
,
,
: “
Y
”,
6
,
, 5 (2009).
,
,
,
,
,
:
“
Y
”,
116
,
, 9 (2009).
,
,
,
,
,
,
: “
Y
”,
73
,
, 9 (2009).
,
,
,
,
,
,
: “
DNA
”,
81
,(
),
, 9 (2009).

- 474 -

1

Radiation
Biology Team
RNC
Publications
Publications
Journal[](Original Papers) *Subject to Peer Review
Ichida H., Yoneyama K., Koba T., and Abe T.: “Epigenetic modiﬁcation of rhizobial genome is essential for efﬁcient nodulation”, Biochem. Biophys. Res. Commun.
389, 301–304 (2009).
Fujiwara M., Dongliang L., Kazama Y., Abe T., Uno T.,
Yamagata H., Kanamaru K., and Itoh R. D.: “Further evaluation of the localization and functionality ofhemagglutinin epitope- and ﬂuorescent protein-tagged
AtMinD1 in Arabidopsis thaliana”, Biosci. Biotechnol.
Biochem. 73, No. 7, pp. 1693–1697 (2009).
Kikuchi S., Saito Y., Ryuto H., Fukunishi N., Abe T.,
Tanaka H., and Tsujimoto H.: “Eﬀects of heavy-ion
beams on chromosomes of common wheat, Triticum aestivum”, Muta. Res./Fund. Mol. Mech. Mutagen. 669,
63–66 (2009).
Niwa K., Hayashi Y., Abe T., and Aruga Y.: “Induction and isolation of pigmentation mutants of Porphyra
yezoensis (Bangiales, Rhodophyta) by heavy-ion beamirradiation”, Phycol. Res. 57, No. 3, pp. 194–202(2009).
Kazama Y., Fujiwara M., Koizumi A., Nishihara K.,
Kifune E., Abe T., and Kawano S.: “A SUPERMANlike gene is exclusively expressed in female ﬂowers of the
dioecious plant Silene latifolia”, Plant Cell Physiol. 50,
No. 6, pp. 1127–1141 (2009).
Shimada S., Ogawa T., Kitagawa S., Suzuki T., Ikari
C., Shitsukawa N., Abe T., Kawahigashi H., KikuchiR., Handa H., and Murai K.: “A genetic networkof ﬂowering-time genes in wheat leaves, in whichan APETALA1/FRUITFULL-like gene, VRN1, is upstream of FLOWERING LOCUS T”, Plant J. 58, 668–
681 (2009).
,,: “”, Cellulose Communications
16, No. 2, pp. 54–57 (2009).
,
,
,
,
,
,
,
: “
X
Pb
Cu
”, X
40, 183–193 (2009).
,
,
,
,
,
,
,
,
: “
”,

, No. 24, pp. 12–19 (2009).

,,(Review)
,

,

: “
”,

551–558 (2008).
,
,

,

: “
”,

pp. 22–26 (2009).

63,, No. 121,

Proc.][
Book• Proceedings(Review),: “DNA”, DNA
Vol.17,DNA,, pp.
118–120 (2009).
,
,
,
,
,
:
”,
“
132
188
,
, 2009–11,,, pp. 27–34 (2009).
,
: “
2
”,
2
,
, 2009–11,,, pp. 29–32 (2009).
,
,
: “
Y
”,
2
,
, 2009–11,,, pp. 33–36 (2009).
,
,
,
: “
”,
21
,
, 2010–1,,, pp. 91–94 (2010).

Oral Presentations
Oral Presentations((International) Conference etc.)
Takada S., Kitajima N., Tarada Y., Abe T., HokuraA., and Nakai I.: “Study on Cd storage and detoxication mechanism of tobacco by micro-XRF-XAFS analysis using high-eneryg synchrotron radiation”, International Symposium on Metallomics (ISM 2009), Cincinnati, USA, June (2009).
Niwa K. and Abe T.: “Occurrence of chimeras with mosaic patterns in archeospore germlings of the marine
crop Porphya yezoensis Ueda (Bangiales, Phodophyta)”,
Plant Biology 2009: Joint Annual Meetings of the American Society of Plant Biologists and the Phycological Society of America, Honolulu, USA, July (2009).
Kazama Y., Liu Y., Hirano T., Ohbu S., Hayashi Y.,
Matsuyama T., and Abe T.: “The powerful technology
for inducing deletion mutations in Arabidopsis thaliana”,
Plant Biology 2009: Joint Annual Meetings of the American Society of Plant Biologists and the Phycological Society of America, (American Society of Plant Biologist),
Honolulu, USA, July (2009).
Kazama Y., Takehisa H., Fujiwara M., Ohbu S., Hayashi
Y., and Abe T.: “A DFR-deﬁcient white ﬂower mutant induced by heavy-ion beam irradiation in Nicotiana
tabacum”, 5th International Workshop on Anthocyanins(IWA 2009), Nagoya, Sept. (2009).
Abe T., Hayashi Y., Kazama Y., Nishihara K., HiranoT., Nakagawa M., Ohbu S., Kanaya T., Miyazaki
K., and Suzuki K.: “New ﬂowr cultivar produced byheavy-ion beam irradiation in RIBF”, 5th International
Workshop on Anthocyanins (IWA 2009), Nagoya, Sept.
(2009).
Murakami K., Yamamoto T., Fujimoto K., Okabe K.,- 475 -

1

Masuda M., Abe T., and Maeda K.: “Low-Pungent
Sweet Pepper Selected under Continuous Fluorescent illumination”, 6th International Symposium Light in Horticulture, (The International Society for Horticultural
Science), Tsukuba, Nov. (2009).
((Domestic )Conference)
,
: “
LET
”,
,(
),
, 5 (2008).
: “
”,
,(
),
,5
(2008).
,
,
,
,
,
,
,
,
,
,
,
,
: “
”,
115
,(
),
, 3 (2009).
,
,
,
,
,
: “
”,
,3

115

,(

),

(2009).
,

,

,

,(

),

,3

,

Kim H.,
,

,

,

,

,(
,

,

”,
(2009).
,

,

,3

),
,

,

: “DNA”,(2009).
,: “DNA

,3

21
,

21
,

,

: “
”,

50

(2009).

: “
”,
-,

,3

(2009).
: “

”,
,

,3

(2009).
,

,

,

”,

6

,

,6

,

: “
Y
,

, 5 (2009).
: “

”,

,
,

,
: “

,

,

2
”,
,

(2009).
,,,

27, 7 (2009).
,
: “
”,
27
,
, 7 (2009).

,

,

(
21

,(
,

),

,

,

,

,

: “DNA)”,, 9 (2009).
,
,

,

: “
”,

21

,
,
,

,9

,
: “
),
,
”,
,

(2009).
,,”,, 9 (2009).
,
,

,

116
,

,
116

,

: “
,

,

,(

,9
,

(2009).
:

“
Y

”,
116
, 9 (2009).
,, Liu Y.,
,
,
,
,
: “
LET
DNA
”,
116
,
(
),
, 9 (2009).
,
,
,
: “
FISH
”,
21
,
,9
(2009).
,
,
,
,
,
,
: “
Y
”,
73
,
,9
(2009).
: “
”,
21
1
,(
),
, 9 (2009).
,
,
,
,
,
,
: “
DNA
”,
81
,
, 9 (2009).
,
,
,
,
,
,
: “
DNA
”,
81
,(
),
, 9 (2009).
,
,
,
,
,
,
: “
”,
132
188
,
, 11 (2009).
,
: “
2
”,
2
,( 2
),
, 11
(2009).
,
,
: “
Y
”,
2
,
, 11
(2009).
,
,
,
: “
DNA
,

,
,

- 476 -

,

”,
20
DNA
, 11 (2009).
,,: “DNA2

”,
18(2009).
,

, (

DNA
),

DNA

, Li D.,
,

, 11

: “
”,

DNA
DNA

),
,

, 11
,

18
(2009).
,

,

”,
,(

,

(2010).
,

3

,

”,
45 X
),
, 11 (2009).
, Eichinger C. S.,
,
,
: “

,(
,

,

,
DNA

,

,
,

32

,
, 12 (2009).
,
,
,
,
,
,
: “Analysis on the functional domains of Mcm10 inmammalian cells”,
32
,(
),
, 12
(2009).
,: “DNA”, DNA
2, (DNA),, 12(2009).
,
,
,
,
: “
Cd
X
”,
23
,
, 1 (2010).
,
,
,
: “
”,
21
,(
),
, 1 (2010).
,
,
,
: “
”,
147
Metal hyperaccumulator,(),, 1 (2010).
,
,
,
: “
”,
10
,
,1
(2010).
,
,
,
,
,
,
,
: “
LET
”,
117
,(
),
, 3 (2010).
,
,
,
,
,
,
,
,
,
,
,
,
: “

,
,
,

117
,
,
, Liu Y.,
,
: “
LET
(1)”,
, 3 (2010).
, Arner E. A.,
,
,
,

”,
, 3 (2010).

117

,3
,

,3
,

”,
(2010).
,

: “
51

”,

”,

”,

),

2010

,

,

: “

: “
(

),

,
AtMinD1

DNA
,

,
,

,
: “HA

22
,
,

,
: “
”,
51

(2010).
,
,
,
“
MinE
FtsZ1-GFP
,
,3

,3

,

,

,
,

,

(2010).
,

,

,
,

,3

,
”,

:
51

(2010).

(2010).
,
DNA
117

,

,
: “

,(

- 477 -3

RI Applications Team
RNC
Oral Presentations
Oral Presentations((International) Conference etc.)
Ooe K., Yahagi W., Komori Y., Fujisawa H., TakayamaR., Kikunaga H., Yoshimura T., Takahashi N., Haba H.,
Kudou Y., Ezaki Y., Takahisa K., and Shinohara A.:“Solvent Extraction Studies of Molybdenum and Tungsten as Homologues of Seaborgium (Element 106)”, 7thWorkshop on the Chemistry of the Heaviest Elements,(Mainz University), Mainz, Germany, Oct. (2009).
()Conference)(Domestic,,: “α”, 200953,(),,9(2009).
,
,
,
,
,
,
,
,
,
,
,
,
: “106”, 200953,(),, 9 (2009).
,,: “nat Hf”, 200953,(),, 9 (2009).
,
,
,
,
,
:
“
12
19
”,
32
,(
),
, 11
(2009).

- 478 -

1

User Liaisonand Industrial Cooperation Group
RNC
Publications
Publications[Journal](Original Papers) *Subject to Peer Review
Takeuchi S., Aoi N., Motobayashi T., Ota S., TakeshitaE., Suzuki H., Baba H., Fukui T., Hashimoto Y., Ieki
K., Imai N., Iwasaki H., Kanno S., Kondo Y., Kubo T.,
Kurita K., Minemura T., Nakamura T., Okumura T.,
Onishi T., Sakurai H., Shimoura S., Sugou R., SuzukiD., Suzuki M., Takashina M., Tamaki M., Tanaka K.,
Togano Y., and Yamada K.: “Low-Iying States in 32Mg
studied by proton inelastic scattering”, Phys. Rev. C
79, No. 5, pp. 054319-1–054319-11 (2009).

- 479 -

1

Industrial
RNC Cooperation Team
Publications
Publications
Journal[](Original Papers) *Subject to Peer Review
Mitsudo T., Nakajima Y., Remijn G. B., Takeichi H., GotoY., and Tobimatsu S.: “Electrophysiological Evidence ofAuditory Temporal Perception Related to the Assimilation Between Two Neighboring Time Intervals”, NeuroQuantology 7, No. 1, pp. 114–127 (2009).
,
,
,
,
,
,
,
,
,
,
: “
”,
28, No. 1, pp. 44–58 (2009).

Oral Presentations
Oral Presentations()Conference)(Domestic: “”,
19(JNNS2009),, 9 (2009).
: “
”,
55
,
, 11
(2009).

- 480 -

1

Safety
Management Group
RNC
Publications
Publications[Journal](Review)
,

,
,

,
,

,
,

,
,

,
,

,

,
,
,
,
,
,
: “Research on Radiation Protectionin the Application of New Technologies for Proton andHeavy Ion Radiotherapy”,
28, No. 4, pp. 172–206 (2009).

Oral Presentations
Oral Presentations((International) Conference etc.)
Uwamino Y., Mukai H., Higurashi R., Akashio A., Fukuda
H., Sakamoto H., Yoshida A., and Yoshida K.: “Dosimetry around BigRIPS at RIKEN RIBF”, 11th Neutron
and Ion Dosimetry Symposium, (iThemba Laboratory
for Accelerator-Based Sciences), Cape Town, South
Africa, Oct. (2009).

- 481 -

1

CNS (Center for Nuclear Study, Graduate School of
東京大学理学系研究科附属原子核科学研究センター
Science, University of Tokyo)

誌

上発Publications
表 Publications

雑誌][Journal（原著論文）＊印は査読制度がある論文誌(Original Papers)*Subject to Peer Review
Aamodt K. et al for the ALICE Collaboration: “First proton+proton collisions at the LHC as observed with the
ALICE detector-Measurement of the charged-particle√
pseudorapidity density at s = 900 GeV”, Eur. Phys.
J. C65, 111-125, 2010,*
Aamodt K. et al for the ALICE Collaboration: “Alignmentof the ALICE Inner Tracking System with cosmic-ray
tracks”, JINST, 5, PO3003, 2010,*
Adare A. et al for the PHENIX Collaboration: “Enhanced
production of direct photons in Au+Au collisions at√
sN N =200 GeV and implications for the initial temperature”, Phys. Rev. Lett. 104, 132301, 2010,*
Adare A. et al for the PHENIX Collaboration: “Detailed measurement of the e+ e− pair continuum in p + p√
and Au+Au collisions at sN N = 200-GeV and implications for direct photon production”, Phys. Rev. C
81, 034911, 2010,*
Adare A. et al for the PHENIX Collaboration: “Double
Helicity Dependence of Jet Properties from Dihadrons√
in Longitudinally Polarized p + p Collisions at s =200-GeV”, Phys. Rev. D81, 012002, 2010,*
Adanasiev S. et al for the PHENIX Collaboration: “Systematic Studies of Elliptic Flow Measure√ments in Au+Au Collisions at sN N = 200-GeV”,
Phys. Rev. C80, 024909, 2009,*
Adanasiev S. et al for the PHENIX Collaboration:“High-pT π 0 Production with Respect to the Reaction√
Plane in Au + Au Collisions at sN N = 200-GeV”,
Phys. Rev. C80, 054907, 2009,*
Adanasiev S. et al for the PHENIX Collaboration:“Kaon interferometric probes of space-time evolu√sN N = 200-GeV”,
tion in Au+Au collisions at
Phys. Rev. Lett, 103, 142301, 2009,*
Adare A. et al for the PHENIX Collaboration: “Measurement of Bottom versus Charm as a Functionof Transverse Momentum with Electron-Hadron Cor√s =200 GeV”,
relations in p + p Collisions at
Phys. Rev. Lett. 103, 082002, 2009,*
Adare A. et al for the PHENIX Collaboration: “PhotonHadron Jet Correlations in p + p and Au+Au Collisions√
at s = 200-GeV”, Phys. Rev. C80, 024908, 2009,*
Adanasiev S. et al for the PHENIX Collaboration: “Photoproduction of J/ψ and of high mass e+ e− in ultra√
peripheral Au+Au collisions at sN N = 200-GeV”,
Phys. Lett. B679, 321-329, 2009,*
Adare A. et al for the PHENIX Collaboration: “ThePolarized gluon contribution to the proton spin fromthe double helicity asymmetry in inclusive π 0 produc√tion in polarized p + p collisions at s = 200-GeV”,
Phys. Rev. Lett. 103, 012003, 2009,*

Tamagawa T., Hayato A., Asami F., Abe K., Iwamoto S.,
Nakamura S., Harayama A., Iwahashi T., Konami S.,
Hamagaki H., Yamaguchi Y.L., Tawara H., MakishimaK., “Development of Thick-foil and Fine-pitch GEMs
with a Laser Etching Technique”, Nucl. Instrum. Meth.
in Physics Research A 608 (2009) 390 – 396.,*
He J. J., Kubono S., Teranishi T., Hu J., Notani M., Baba
H., Nishimura S., Moon J. Y., Nishimura M., Iwasaki H.,
Yanagisawa Y., Hokoiwa N., Kibe M., Lee J. H., Kato S.,
Gono Y., and Lee C. S.: “Investigation of excited statesin 22Mg via resonant elastic scattering of 21Na+p andits astrophysical implications”, Phys. Rev. C 80 (2009)015801-6,*
Ichikawa Y., Onishi T.K., Suzuki D., Iwasaki H., Kubo
T., Naik V., Chakrabarti A., Aoi N., Brown B.A.,
Fukuda N., Kubono S., Motobayashi T., Nakabayashi
T., Nakamura T., Nakao T., Okumura T., Ong H.J.,
Suzuki H., Suzuki M.K., Teranishi T., Yamada K.N.,
Yamaguchi H., Sakurai H., “β decay of the proton-richnucleus 24Si and its mirror asymmetry”, Phys. Rev. C
80, 044302 (2009),*
Doornenbal P., Scheit H., Aoi N., Takeuchi S., Li K.,
Takeshita E., Wang H., Baba H., Deguchi S., Fukuda N.,
Geissel H., Gernhauser R., Gibelin J., Hachiuma I., Hara
Y., Hinke C., Inabe N., Itahashi K., Itoh S., Kameda
D., Kanno S., Kawada Y., Kobayashi N., Kondo Y.,
Krucken R., Kubo T., Kuboki T., Kusaka K., Lantz
M., Michimasa S., Motobayashi T., Nakamura T., Nakao
T., Namihira K., Nishimura S., Ohnishi T., Ohtake M.,
Orr N.A., Otsu H., Ozeki K., Satou Y., Shimoura S.,
Sumikama T., Takechi M., Takeda H., N. K., Tanaka
K., Togano Y., Winkler M., Yanagisawa Y., Yoneda K.,
Yoshida A., Yoshida K., Sakurai H., “Spectroscopy of
32
Ne and the Island of Inversion”, Phys. Rev. Lett.
103, (2009) 032501, *Hagino K., Sagawa H., Nakamura T., Shimoura S., “Twoparticle correlations in continuum dipole transitions in
Borromean nuclei”, Phys. Rev. C 80, (2009) 031301,*
Imai N., Aoi N., J. H., Sakurai H., Demichi K., Kawasaki
H., Baba H., Dombrádi Zs., Elekes Z., Fukuda N., FülöpZs., Gelberg A., Gomi T., Hasegawa H., Ishikawa K.,
Ishihara M., Iwasaki H., Kaneko E., Kanno S., KishidaT., Kondo Y., Kubo T., Kurita K., Michimasa S.,
Minemura T., Miura M., Motobayashi T., Nakamura T.,
Notani M., K. T., Saito A., Shimoura S., Sugimoto T.,
K. M., Takeshita E., Takeuchi S., Tamaki M., Watanabe
H., Yoneda K., “First lifetime measurement of 2+
1 statein 12 Be”, Phys. Lett. B 673, (2009) 179 – 182,*
Kondo Y., Nakamura T., Satou Y., Matsumoto T., Aoi N.,
Endo N., Fukuda N., Gomi T., Hashimoto Y., Ishihara
M., Kawai S., Kitayama M., Kobayashi T., Matsuda
Y., Matsui N., Motobayashi T., Nakabayashi T., Ogata
K., Okumura T., Ong H.J., Onishi T.K., Otsu H.,
Sakurai H., Shimoura S., Shinohara M., Sugimoto T.,
Takeuchi S., Tamaki M., Togano Y., Yanagisawa Y.,- 482 -

1

“One-neutron removal reactions of 18 C and 19 C on a
proton target”, Phys. Rev. C 79, (2009) 014602, *Nakamura T., Kobayashi N., Kondo Y., Satou Y., Aoi N.,
Baba H., Deguchi S., Fukuda N., Gibelin J., Inabe N.,
Ishihara M., Kameda D., Kawada Y., Kubo T., Kusaka
K., Mengoni A., Motobayashi T., Ohnishi T., Ohtake
M., Orr N.A., Otsu H., Otsuka T., Saito A., Sakurai H.,
Shimoura S., Sumikama T., Takeda H., Takeshita E.,
Takechi M., Takeuchi S., Tanaka K., N. K., Tanaka N.,
Togano Y., Utsuno Y., Yoneda K., Yoshida A., YoshidaK., “ Halo Structure of the Island of Inversion Nucleus
31Ne”, Phys. Rev. Lett. 103, (2009) 262501,*
Takeuchi S., Aoi N., Motobayashi T., Ota S., TakeshitaE., Suzuki H., Baba H., Fukui T., Hashimoto Y., Ieki
K., Imai N., Iwasaki H., Kanno S., Kondo Y., Kubo T.,
Kurita K., Minemura T., Nakabayashi T., Nakamura T.,
Okumura T., K. T., Sakurai H., Shimoura S., Sugou R.,
Suzuki D., K. M., Takashina M., Tamaki M., Tanaka
K., Togano Y., Yamada K., “ Low-lying states in 32 Mg
studied by proton inelastic scattering”, Phys. Rev. C
79, (2009) 054319,*
Ideguchi E., Cederwall B., Ganioğlu E., Hadinia B.,
Lagergren K., Bäck T., Johnson A., Wyss R., Eeckhaudt
S., Grahn T., Greenlees P., Julin R., Juutinen S.,
Kettunen H., Leino M., Leppanen A.-P., Nieminen
P., Nyman M., Pakarinen J., Rahkila P., Scholey C.,
Uusitalo J., Joss D.T., Paul E.S., Wiseman D.R.,
Wadsworth R., Afanasjev A.V., Ragnarsson I., “Highspin intruder band in 107 In”, Phys. Rev. C 81, (2010)
034303,*
Scholey C., Andgren K., Bianco L., Cederwall B., G. I.,
Eeckhaudt S., Ertürk S., GomezHornillos M.B., Grahn
T., T. P., Hadinia B., Ideguchi E., Jones P., T. D., JulinR., Juutinen S., Ketelhut S., Leino M., Leppänen A.P., Nieminen P., Niikura M., Nyman M., O’Donnell D.,
D. R., Pakarinen J., Rahkila P., Sarén J., SandzeliusM., Simpson J., Sorri J., Thomson J., Uusitalo J.,
Venhart M., “Isomeric and ground-state properties of
171
167
163
Rev. C 81, (2010)78 Pt, 76 Os,and 74 W”, Phys.
014306,*
Hadinia B., Cederwall B., D. R., Sandzelius M., Scholey
C., Andgren K., Bäck T., Ganioğlu E., Gómez M.B.,
Hornillos , Grahn T., T. P., Ideguchi E., Jakobsson U.,
Johnson A., M. P., Julin R., Juutinen J., Ketelhut S.,
Khaplanov A., Leino M., Niikura M., Nyman M., ÖzgürI., S. E., Peura P., Rahkila P., Sarén J., Sorri J., UusitaloJ., Wyss R., “Identification of gamma rays from 172 Au
and alpha decays of 172 Au, 168 Ir, and 164 Re”, Phys. Rev.
C 80, (2009) 064310,*
Morita K., Morimoto K., Kaji D., Haba H., Ozeki K.,
Kudou Y., Sato N., Sumita T., Yoneda A., Ichikawa T.,
Fujimori Y., Goto S., Ideguchi E., Kasamatsu Y., Katori
K., Komori Y., Koura H., Kudo H., Ooe K., Ozawa
A., Tokanai F., Tsukada K., Yamaguchi T., Yoshida A.,“Decay Properties of 266 Bh and 262 Db Produced in the

Cm + 23 Na Reaction”, J. Phys. Soc. Jpn. 78, (2009)064201,*
Tanaka K., Yamaguchi T., Suzuki T., Ohtsubo T., Fukuda
M., Nishimura D., Takechi M., Ogata K., Ozawa A.,
Izumikawa T., Aiba T., Aoi N., Baba H., Hashizume
Y., Inafuku K., Iwasa N., Kobayashi K., Komuro
M., Kondo Y., Kubo T., Kurokawa M., MatsuyamaT., Michimasa S., Motobayashi T., Nakabayashi T.,
Nakajima S., Nakamura T., Sakurai H., Shinoda R.,
Shinohara M., Suzuki H., Takeshita E., Takeuchi S.,
Togano Y., Yamada K., Yasuno T., Yoshitake M., “Observation of a Large Reaction Cross Section in the DripLine Nucleus 22 C”, Phys. Rev. Lett. 104, (2010)
062701,*
Suzuki D., Iwasaki H., Beaumel D., Nalpas L., PollaccoE., Assié M., Baba H., Blumenfeld Y., De N., Séréville, Drouart A., Franchoo S., Gillibert A., Guillot J.,
Hammache F., Keeley N., Lapoux V., Maréchal F.,
Michimasa S., Mougeot X., Mukha I., Okamura H., Otsu
H., Ramus A., Roussel-Chomaz P., Sakurai H., Scarpaci
J.A., Sorlin O., Stefan I., Takechi M., “Breakdown of
the Z = 8 Shell Closure in Unbound 12 O and its Mirror
Symmetry ”, Phys. Rev. Lett. 103, (2009) 152503,*
Ideguchi E., Ota S., Morikawa T., Oshima M., Koizumi M.,
Toh Y., Kimura A., Harada H., Furutaka K., Nakamura
S., Kitatani F., Hatsukawa Y., Shizuma T., Sugawara
M., Miyatake H., X. Y., Hirayama Y., Oi M., “Superdeformation in asymmetric N>Z nucleus 40 Ar”, Phys.
Lett. B 686 (2010) 18–22,*
Sekiguchi K., Sakai H., Witala H., Glockle W., Golak
J., Itoh K., Kamada H., Kawabata T., Kuboki H.,
Maeda Y., Nogga A., Okamura H., Sakaguchi S.,
Sakamoto N., Sasamoto Y., Sasano M., Skibiński R.,
Suda K., Takahashi Y., Uesaka T., Wakasa T., Yako K.,pp)n reaction“Three-nucleon force effects in the 1 H(d,at 135 MeV/nucleon”, Phys. Rev. C 79 (2009) 054008,*
Yako K., Sasano M., Miki K., Sakai H., Dozono M.,
Frekers D., B. M., Hatanaka K., Ihara E., Kato M.,
Kawabata T., Kuboki H., Maeda Y., Matsubara H.,
Muto K., Noji S., Okamura H., H. T., Sakaguchi S.,
Sakemi Y., Sasamoto Y., Sekiguchi K., Shimizu Y., Suda
K., Tameshige Y., Tamii A., Uesaka T., Wakasa T.,
Zheng H., “Gamow-Teller Strength Distributions in 48 Sc
by the 48 Ca(p, n) and 48 Ti(n, p) Reactions and TwoNeutrino Double-β Decay Nuclear Matrix Elements”,
Physical Review Letters 103 (2009) 012503,*
Tamii A., Fujita Y., Matsubara H., Adachi T., CarterJ., Dozono M., Fujita H., Fujita K., Hashimoto H.,
Hatanaka K., Itahashi T., Itoh M., Kawabata T.,
Nakanishi K., Ninomiya S., Perez-Cerdan A.B., Popescu
L., Rubio B., Saito T., Sakaguchi H., Sakemi Y.,
Sasamoto Y., Shimbara Y., Shimizu Y., Smit F.D.,
Tameshige Y., Yosoi M., Zenihiro J., “Measurement ofhigh energy resolution inelastic proton scattering at andclose to zero degrees”, Nucl.Instrum.Methods Phys.Res.

- 483 -

248

2

A605, 326 (2009),*
Suzuki T., Honma M., Higashiyama K., Yoshida T.,
Kajino T., Otsuka T., Umeda H., Nomoto K.,“Neutrino-induced reactions on 56Fe
and 56Ni, andproduction of 55Mn in population III stars”, Phys. Rev.
C 79 (2009) 061603(R)/1-4,*
Otsuka T., Suzuki T., Honma M., Utsuno Y., TsunodaN., Tsukiyama K., Hjorth-Jensen M., “Novel featuresof nuclear forces and shell evolutions in exotic nuclei”,
Phys. Rev. Lett. 104 (2010) 012501/1-4,*
Suzuki T., Otsuka T., “Exotic Electromagnetic Transitions
in Neutron- rich Carbon Isotopes”, Int.Journal of Modern Physics E18 (2009) 1992–1996,*
単行本・
Proc.][Book• Proceedings（原著論文）＊印は査読制度がある論文誌(Original Papers)*Subject to Peer Review
Gunji T.: “Quarkonia production in high-energy heavyion collisions at the RHIC”. Proc. of the International
Conference on Strangeness in Quark Matter 2008, Oct.
6-10, 2008, Tsinghua Univeristy, Beijing, China J. Phys.
G 36, -64015, 2009,*
Tsuchimoto Y. for the PHENIX Collaboration: “InMedium Modifications of Low-Mass Vector Mesons in
PHENIX at RHIC”, Proc. of the 21st International
Conference on Ultra-Relativistic Nucleus-Nucleus Collisions (QM2009), Mar. 30–Apr. 4, 2009, Knoxville,
USA, Nucl. Phys. A 830 (2009) 487c–490c,*
Yamaguchi Y.L. for the PHENIX collaboration: “Measurements of Soft and Intermediate pT Photons from
Hot and Dense Matter at RHIC-PHENIX”, Proc. of the
21st International Conference on Ultra-Relativistic Nucleus Nucleus Collisions (Quark Matter 2009), Mar. 30–
Apr. 5, 2009, Knoxville, Tennessee, USA, Nucl. Phys.
A 830 (2009) 575c–578c,*
Aramaki Y., for the PHENIX Collaboration: “Reaction
plane dependence of neutral pion production in centerof-mass energy of 200 GeV Au+Au collisions at RHICPHENIX”, Proc. of the eighteenth Particles and Nuclei
International Conference - PANIC08, November 9–14,
2008, Eilat, Israel, Conference record, (2009) pp. 570–
572.
Aramaki Y., for the PHENIX Collaboration: “Study of
QGP with probes associated with photon at RHICPHENIX”, Proc. of the XLIVth Recontres de Moriond,
March 14–21, 2009, La Thuile, Italy, Conference record,(2009) pp. 291–294.
Akimoto R., Hamagaki H., Gunji T., Yamaguchi Y.L.,
Hori Y., “Measurement of the basic features of ThickGEM and Resistive GEM”, Proc. of the 1st International conference on Micro Pattern Gaseous Detectors,
Jun. 12–15, 2009, Crete, Greece, Journal of Instrumentation, 5 (2010)
Cherubini S., Crucilla V., Gulino M., Kiss G., La Cognata
M., Li C., Munhoz M.G., Kroha V., Kubono S.,
Somoryai E., Szanto de Toledo A., Liguori Neto R., De
M.M., Moura , Pizzone R.G., Rapisarda G.G., Sergi

M.L., Souza F.A., Suaide A.A.P., Szanto E., Tabacaru
G., Tudisco S., Tumino A., Wakabayashi Y., Wen Q.,
and , Yamaguchi H., “New results on the Trojan Horse
Method applied to the 10,11 B+p reactions”, Proceedings of the 6th Japan-Italy Symposium on Heavy-Ion
Physics, AIP Conf. Proc. 1120 (2009) 171 - 176,*
Cherubini S., Spitaleri C., Crucilla V., Gulino M., La M.,
Cognata , Lamia L., Pizzone R.G., Romano S., Kubono
S., Yamaguchi H., Wakabayashi Y., Hayakawa S., Iwasa
N., Kato S., Komatsubara H., Teranishi T., Coc A., De
N., Sereville , and , Hammache F., “The study of 18F+p
reaction at astrophysical energies”, Proceedings of the 6thJapan-Italy Symposium on Heavy-Ion Physics, AIP Conf.
Proc. 1120 (2009) 294 - 297,*
Kubono S., Binh D.N., Hayakawa S., Hashimoto H., M. D.,
Wakabayashi Y., Yamaguchi H., Teranishi T., Iwasa N.,
Komatsubara T., Kato S., Khiem L.H., “Nuclear Clusters in Astrophysics”, Proc. of the 10th International
Conference on Nucleus-Nucleus Collisions (NN2009),
August 16-21, 2009, Beijing, China Nucl. Phys. A834
(2010) 647c – 650c,*
Kubono S., Binh D.N., Hayakawa S., Hashimoto T., Kahl
D.M., Yamaguchi H., Wakabayashi Y., Teranishi T.,
Iwasa N., Komatsubara T., Kato S., and , Khiem L.H.,“Nuclear Astrophysics Programs with Low-Energy RI
Beams at CRIB”, Proc. of the International Symposium
on Exotic Nuclei (EXON), Sochi, Russia, October, 2009,AIP Conf. Proc. vol. 1224 (2010) 475 - 481 (2010),*
Kubono S., “Nuclear Cluster Aspects in Astrophysics”,
Proc. of the 5th European Summer School on Nuclear
Astrophysics, Sept. 20 - 27, 2009, Santa Tecla, Italy,
AIP Conf. Proc. vol. 1213 (2010) 107 - 111,*
Yamaguchi H., Wakabayashi Y., Hayakawa S., Binh D.N.,
Kahl D., Kurihara Y., Kubono S., Teranishi T., He
J.J., Kwon Y.K., Nishimura S., Togano Y., Iwasa N.,
Niikura M., and , Khiem L.H., “Nuclear AstrophysicalStudies Using Low-Energy RI Beams at CRIB”, Perspective in Nuclear Physics, AIP conference proceeding
1120 (2009) 189–193,*
Chen J., Chen A.A., Schatz H., Kubono S., Reyes A.B.,
Smith A., Wales B., Ouellet C., Kahl D., Redondo
D.G., Lorusso G., LeNestour J., Conca J.P., Smith
K., Amthor M., Matos M., Yamaguchi H., Iwasa N.,
Hayakawa S., Michimasa S., Teranishi T., Kurihawa Y.,
and , Wakabayashi Y., “Study of astrophysically important states in 26Si with the p(27Si,26Si*)d reaction andthe p(25Al,p)25Al elastic scattering”, Nucl. Phys. A
834 (2010) 667c–669c,*
Niikura M., Ideguchi E., Aoi N., Baba H., Fukuchi T.,
Ichikawa Y., Iwasaki H., Kubo T., Kurokawa M., Liu
M., Michimasa S., Ohnishi T., Onishi T.K., Ota S.,
Shimoura S., Suzuki H., Suzuki D., Wakabayashi Y.,
Yoshida K., Zheng Y., “Yrast spectroscopy in 49−−51 Ti
via fusion-evaporation reaction induced by a radioactivebeam”, Proceedings of the Fifth International Confer-- 484 -

3

ence on Exotic Nuclei and Atomic Masses (ENAM’08),
Sept. 7 – 13, 2008, Ryn, Poland, Eur. Phys. J. A 42
(2009) 471–475,*
Shimoura S., “High-resolution spectroscopy using RIbeams — SHARAQ project”, Proceedings of theFranco-Japanese symposium “New Paradigms in Nuclear Physics”, Sept. 29 – Oct. 2, 2008, Paris, France,
Int. J. Mod. Phys. E 18, (2009) 2011–2014,*
Takeuchi S., Aoi N., Baba H., Kubo T., Motobayashi T.,
Tanaka K., Yamada K., Fukui T., Ota S., Hashimoto Y.,
Kondo Y., Nakabayashi T., Nakamura T., Okumura T.,
Ieki K., Kanno S., Kurita K., Sugou R., Takeshita E.,
Togano Y., Imai N., Minemura T., Iwasaki H., Onishi
T.K., Sakurai H., Suzuki D., Suzuki H., Suzuki M.K.,
Shimoura S., Tamaki M., “Study of low-lying states in32Mg”, Proceedings of the Franco-Japanese symposium“New Paradigms in Nuclear Physics”, Sept. 29 – Oct.
2, 2008, Paris, France, Int. J. Mod. Phys. E 18, (2009)2025–2029,*
Satou Y., Nakamura T., Fukuda N., Sugimoto T., Kondo
Y., Matsui N., Hashimoto Y., Nakabayashi T., Okumura
Y., Shinohara M., Motobayashi T., Yanagisawa Y., Aoi
N., Takeuchi S., Gomi T., Togano Y., Kawai S., Sakurai
H., Ong H.J., Onishi T.K., Shimoura S., Tamaki M.,
Kobayashi T., Otsu H., Endo N., Kitayama M., Ishihara
M., “Invariant mass spectroscopy of 19,17 C and 14 B using
proton inelastic and charge-exchange reactions”, Proc.
the 10th International Conference on Nucleus-Nucleus
Collisions (NN2009), Beijing, China, 16–21 August 2009,
Nucl. Phys. A 834 (2010) 404c–407c,*
Doornenbal P., Scheit H., Aoi N., Takeuchi S., Li K.,
Takeshita E., Wang H., Baba H., Deguchi S., Fukuda N.,
Geissel H., Gernhäuser R., Gibelin J., Hachiuma I., Hara
Y., Hinke C., Inabe N., Itahashi K., Itoh S., Kameda
D., Kanno S., Kawada Y., Kobayashi N., Kondo Y.,
Krücken R., Kubo T., Kuboki T., Kusaka K., Lantz
M., Michimasa S., Motobayashi T., Nakamura T., Nakao
T., Namihira K., Nishimura S., Ohnishi T., Ohtake M.,
Orr N.A., Otsu H., Ozeki K., Satou Y., Shimoura S.,
Sumikama T., Takechi M., Takeda H., Tanaka K.N.,
Tanaka K., Togano Y., Winkler M., Yanagisawa Y.,
Yoneda K., Yoshida A., Yoshida K., Sakurai H., “Exploring the Southern Boundaries of the “Island of Inversion” at the RIBF”, Proc. Int. Conf. on Nuclear
Structure and Dynamics ’09, Dubrovnik, Croatia, 4–8
May 2009, AIP Conf. Proc. 1165 (2009) 82–85,*
Imai N., Aoi N., Ong H.J., Sakurai H., Demichi K.,
Kawasaki H., Baba H., Dombrádi Zs., Elekes Z., Fukuda
N., Fülöp Zs., Gelberg A., Gomi T., Hasegawa H.,
Ishikawa K., Ishihara M., Iwasaki H., Kaneko E.,
Kanno S., Kishida T., Kondo Y., Kubo T., Kurita K.,
Michimasa S., Minemura T., Miura M., Motobayashi
T., Nakamura T., Notani M., Ohnishi T.K., Saito A.,
Shimoura S., Sugimoto T., Suzuki M.K., Takeshita E.,
Takeuchi S., Tamaki M., Watanabe H., Yoneda K., “Ap-plication of Doppler-shift attenuation method to the deexcitation γ rays from the in-flight 12 Be beam”, Proc. of
the 6th Japan-Italy Symposium on Heavy-Ion Physics,
Tokai, Japan, 11–15 November 2008, AIP Conf. Proc.
1120 (2009) 265–269,*
Shimoura S., “High-resolution spectroscopy using direct
reactions of RI beams”, Proc. of the 6th Japan-Italy
Symposium on Heavy-Ion Physics, Tokai, Japan, 11–15
November 2008, AIP Conf. Proc. 1120 (2009) 59–63,*
von Neumann-Cosel P., Adachi T., Bertulani C.A., CarterJ., Dozono M., Fujita H., Fujita K., Fujita Y.,
Hashimoto H., Hatanaka K., Itoh M., Kalmykov Y.,
Kato K., Kawabata T., Matsubara H., Nakanishi K.,
Neveling R., Okamura H., Poltoratska I., Ponomarev
V.Yu., Richter A., Rubio B., Sakaguchi H., Sakemi
Y., Sasamoto Y., Shimbara Y., Shimizu Y., Smit F.D.,
Tameshige Y., Tamii A., Wambach J., Yosoi M., “Complete dipole response in 208Pb from high-resolution polarized proton scattering at 0 degrees”, roc.13th Intern.Symposium on Capture Gamma-Ray Spectroscopy
and elated Topics, Cologne, Germany, 25–29 Aug.2008,
J.Jolie, A.Zilges, N.Warr, A.Blazhev, Eds., p.404, AIP
Conf. Proc. 1090 (2009),*
Suzuki S., Otsuka T., “Structure of Light Neutron-rich Nuclei and Important Roles of Tensor Interaction”, Proc. of
the International Conference on Nuclear Structure andDynamics, May. 4-8, 2009, Dubrovnik, Croatia, AIP
Conf. Proc. 1165 (2009) 54–56,*
口 頭 発Oral
表 Presentations
Oral Presentations(International(国際会議等)Conference etc.)
Gunji T., “Practice n GRID/CAF”, at the Workshop on
ALICE Analysis Workshop for Asian Communities, Jan.
21–23, Hiroshima, Japan
Gunji T., “Forward Physics at LHC energy”, at the Workshop on ALICE upgrades in Asian countries, Nov. 11–
15, Yonsei University, Korea
Gunji T., “Heavy Quarkonia Production in High Energy
Heavy Ion Collisions at RHIC and Perspectives for the
LHC”, at the Workshop on the Expanding Future ofHigh Energy Nuclear Physics at LHC and RHIC, Oct.
13, 2009, Waikoloa, Hawaii, USA.
Gunji T., “Heavy Quarks and Quarkonia Production at
RHIC as a Probe of hot and dense QCD medium”, atthe International Symposium on Multiparticle Dynamics, Sept. 05-09, Gold Sands, Gomel, Belarus
Gunji T., “Quarkonia Melting in expanding hot and dense
medium at RHIC”, at the workshop on Heavy Quarkonium Production in Heavy Ion Collisions, May 25–29,
ECT*, Trento, Italy
Yamaguchi Y.L. for the PHENIX Collaboration, “Measurements of low pT direct photons in PHENIX”, atthe Workshop on the Expanding Future of High Energy Nuclear Physics at LHC and RHIC, Oct. 13, 2009,
Waikoloa, Hawaii, USA.

- 485 -

4

Akimoto R., Hamagaki H., Gunji T., Yamaguchi Y.L.,
Hori Y., “Measurement of the basic features of ThickGEM and Resistive GEM” at the 1st International conference on Micro Pattern Gaseous Detectors, Jun. 12–
15, 2009, Orthodox Academy of Crete Conference Center, Crete, Greece.
Hori Y., “A simulation study for a Forward Calorimeter
upgrade plan in ALICE at LHC”, at the Workshop on
ALICE upgrades in Asian countries, Nov. 11–15, Yonsei
University, Korea
Saito A., “The 6 He+6 He and α+8 He cluster states in 12 Be
via inelastic scattering”, International Symposium on
Forefronts of Researches in Exotic Nuclear Structures(Niigata2010), March 1–4, 2010, Tokamachi, Niigata,Japan.
Shimoura S., “Recent developments of radiation detector
systems for RIBF experiments”, Workshop On Developments of new Scintillator Detectors for Gamma Spectroscopy and Imaging, November 16–17, 2009, Milano,
Italy.
Ota S., Shimoura S., Aoi N., Takeshita E., Takeuchi S.,
Suzuki H., Baba H., Fukuchi T., Fukui T., HashimotoY., Ideguchi E., Ieki K., Iwasa N., Iwasaki H., Kanno S.,
Kondo Y., Nakabayashi T., Nakamura T., Niikura M.,
Okumura T., Onishi T.K., Sakurai H., Shinohara M.,
Suzuki D., K. M., Tamaki M., Tanaka K., Togano Y.,
Wakabayashi Y., Yamada K., “High Resolution In-beamSpectroscopy of island-of-inversion nuclei via alpha induced reaction”, International Workshop on Direct Reactions with Exotic Beams (DREB2009), December 16–
19, 2009, Tallahassee, Florida, USA.
Michimasa S., “SHARAQ Overview and Scientific Programs”, Sept. 9–10, 2009, JUSEIPEN Workshop.
Uesaka T., “Polarized Solid Proton Target in Low Magnetic Field and at High Temperature”, 13th International orkshop on Polarized Sources, Targets and Polarimetry, Sept. 7–11, 2009, Ferrara, Italy.
Kawahara T., Uesaka T., Shimizu Y., Sakaguchi S., Wakui
T., “Pulse structure dependence of the proton spin polarization rate”, 13th International Workshop on Polarized Sources, Targets and Polarimetry Sep. 07–11, 2009,
Camera di Commercio, Ferrara, Italy.
Uesaka T., “SHARAQ Spectrometer —Current status andfuture experimental plans—”, International Symposiumof Exotic Nuclei 2009, Sep. 28–Oct. 2, 2009, Sochi,
RussiaUesaka T., “Current status and future experimental program of the SHARAQ Spectrometer”, 7th Japan-China
Joint Nuclear Physics Symposium, Nov. 9–13, 2009,
University of Tsukuba, Ibaraki, Japan
Uesaka T., “The SHARAQ Spectrometer”, ICHOR-EFES
International Symposium on New Facet of Spin-Isospin
Responses 2010, Feb. 18–21, 2010, University of Tokyo,
Tokyo, Japan
Shimizu Y., “Spin dependent momentum distribution of

proton in 3 He studied via proton induced exclusive
knockout reaction”, 19th International IUPAP Conference on Few-Body Problems in Physics, FB19, Aug. 31–
Sep. 5, University of Bonn, Bonn, Germany.
Sasamoto Y., Uesaka T., Sakai H., Shimoura S., NojiS., Yako K., Michimasa S., Ota S., Saito A., Miki K.,
Tokieda H., Miya H., Kawase S., Kubo T., YoshidaK., Ohnishi T., Yanagisawa Y., Fukuda N., Takeda H.,
Kameda D., Aoi N., Takeuchi S., Ichihara T., Baba H.,
Sakaguchi S., Shimizu Y., Schiet H., Doornembal P.,
Kawabata T., Itoh K., Kawahara T., Maeda Y., SaitohT., Itoh M., Zegers R.G.T., Sasano M., Roussel-ChomazP., Berg G.P.A., “The super-allowed Fermi type charge
exchange reaction for studies of isovector non-spinflip monopole resonance”, ICHOR-EFES International
Symposium on New Facet of Spin-Isospin Responses(SIR2010) , Feb. 18–21, 2010, Koshiba Hall, Universityof Tokyo, Japan.
Ota S., “High-resolution in-beam spectroscopy of islandof-inversion nuclei via alpha induced reactions”, Direct
Reactions with Exotic Beams (DREB) 2009, Dec. 16–
19, 2009, Florida State University, Tallahassee, Florida,USA.
Ota S., “Active Target in CNS, UT”, Instrumentation
discussion session, Direct Reactions with Exotic Beams(DREB) 2009, Dec. 16, 2009, Florida State University,
Tallahassee, Florida, USA.
Ota S., “Active Target Development in CNS”, GETACTAR General Meeting, Jan. 11–15, 2010, Ferme dela Rançonnière, Crepon, France.
Ota S., “Study of giant resonances in unstable nuclei
with CNS Active Target”, ICHOR-EFES International
Symposium on New Facet of Spin-Isospin Responses(SIR2010) , Feb. 18–21, 2010, Koshiba Hall, Universityof Tokyo, Japan.
Miki K., Sakai H., Uesaka T., Baba H., Berg G.P.A.,
Fukuda N., Kameda D., Kawabata T., Kawase S., Kubo
T., Kusaka K., Michimasa S., Miya H., Noji S., OhnishiT., Ota S., Saito A., Sasamoto Y., Sasano M., ShimouraS., Takeda H., Tokieda H., Yako K., Yanagisawa Y.,
Yoshida A., Yoshida K., and , Zegers R.G.T., “Search
for the Isovector Spin Monopole Resonance via the208
Pb,90 Zr(t,3 He) Reactions at 300 MeV/u”, The 4th
LACM-EFES-JUSTIPEN Workshop, Mar. 15–17, 2010,
Oak Ridge National Laboratory, Tennessee, USA
Miki K., Sakai H., Uesaka T., Baba H., Berg G.P.A.,
Fukuda N., Kameda D., Kawabata T., Kawase S.,
Kubo T., Kusaka K., Michimasa S., Miya H., Noji S.,
Ohnishi T., Ota S., Saito A., Sasamoto Y., Sasano
M., Shimoura S., Takeda H., Tokieda H., Yako K.,
Yanagisawa Y., Yoshida A., Yoshida K., and , Zegers
R.G.T., “Measurement of the 208 Pb and 90 Zr(t,3 He) reactions at 300 MeV/u – the first physics measurementwith SHARAQ –”, ICHOR-EFES International Symposium on New Facet of Spin-Isospin Responses (SIR2010),- 486 -

5

Feb. 18–21, 2010, University of Tokyo, Tokyo, Japan
Yamaguchi H., Hashimoto T., Hayakawa S., Binh D.N.,
Kahl D., Kubono S., “Nuclear astrophysics and structure studies using low-energy RI beams at CRIB”, 7thJapan-China Joint Nuclear Physics Symposium, November 9–13, 2009, Tsukuba University, Ibaraki, Japan.
Yamaguchi H., Hashimoto T., Hayakawa S., Binh D.N.,
Kahl D., Kubono S., “Status of the studies on nuclear reactions and structures at CRIB”, The 6th International
Workshop on “Physics with Stopped and Slow Radioisotope Beams (SSRI)”, Mar 1–2, 2010, Tokyo Institute ofTechnology, Tokyo, Japan.
Yamaguchi H., Hashimoto T., Hayakawa S., Binh D.N.,
Kahl D., Kubono S., “Studies for alpha-induced astrophysical reactions at CRIB”, The 10th. International
Symposium on. Origin of Matter and Evolution of the
Galaxies (OMEG10), March 8–10, 2010, RCNP, Osaka
University, Osaka, Japan.
Suzuki T., Otsuka T., “Structure of Light Neutron- rich
Nuclei and Important Roles of Tensor Interaction”, International Conference on Nuclear Structure and Dynamics,
May 2009, Dubrovnik, Croatia
Suzuki T., “Structure of Light Exotic Nuclei”, International Conference on Nuclear Structure and Related
Topics, June 2009, Dubna, Russia
Suzuki T., “Neutrino-induced Reactions on Nuclei and
Nucleosynthesis in Stars”, Neutrinos and Dark Matter
2009, Sept. 2009, Wisconsin University, U.S.A.
T. Suzuki, M. Honma, K. Higashiyama, T. Yoshida, T. Kajino, T. Otsuka, H. Umeda and K. Nomoto (Oral):“Neutrino-induced Reactions on Ni and Fe Isotopes andNucleo- synthesis in Stars”, 3rd Joint Meeting of the
APS-DNP and Physical Society of Japan, Oct. 2009,
Hawaii, U.S.A.
Suzuki T., “Spin Resposes in Nuclei, Neutrino-induced
Reactions and Nucleo- synthesis in Stars”, 7th JapanChina Joint Nuclear Physics Symposium, Nov. 2009,Univ. of Tsukuba, Japan
Suzuki T., “Gamow-Teller Transitions in AstrophysicalProcesses”, EFES- JUSTIPEN workshop, Dec. 2009,
RIKEN, Wako, Japan
Suzuki T., “Shell Model Study of Spin Modes in Ni and
Ca Isotopes”, EFES-NSCLWorkshop on Perspectives on
the Modern Shell Model and Related Experimental Topics, Feb. 2010, Michigan State University, U.S.A.
Suzuki T., “Nuclear Weak Processes and Nucleosynthesis in Stars”, ICOR-EFES International Symposium on
New Facet of Spin-isospin Responses (SIR2010), Feb.
2010, Koshiba Hall, Univ. of Tokyo, Japan
Suzuki T., Yoshida T., Utsuno Y., “Half-lives of N=126
Isotones and the r-Process”, 10th International Symposium on Origin of Matter and Evolution of the Galaxies(OMEG10), Mar. 2010, RCNP, Osaka, Japan
Suzuki T., “GT and FF Transitions in Astrophysical Processes”, The 4th LACM- EFES-JUSTIPEN Workshop,

Mar. 2010, Oak Ridge, USA
Yoshida T., Kato K., “Algebraic N alpha model (applications for 12 C)”, Hadron and Nuclear Physics (HNP09),
Nov. 16-19, 2009, RCNP, Osaka, Japan.
Gunji T., “Quarkonia Melting in expanding hot and dense
medium at RHIC”, at the 3rd Joint Meeting of the
APS Division of Nuclear Physics and Physical Societyof Japan, Oct. 14–17, 2009, Hilton Waikoloa Village,
Hawaii, USA.
Tsuchimoto Y., for the PHENIX Collaboration: “Measurement ofLow-Mass Vector Mesons (LVM)in PHENIX
at RHIC”, at the 3rd Joint Meeting of the APS Divisionof Nuclear Physics and Physical Society of Japan, Oct.
14–17, 2009, Hilton Waikoloa Village, Hawaii, USA.
Aramaki Y., for the PHENIX Collaboration: “Neutralpion production with respect to the reaction plane in√sN N = 200 GeV Au+Au collisions at PHENIX”, 3rd
Joint Meeting of the Nuclear Physics Divisions of the
APS and The Physical Society of Japan, October 13–
17, 2009, Waikoloa, Hawaii, USA.
Akimoto R., Ota S., Michimasa S., Gunji T., Yamaguchi
H., Hashimoto T., Tokieda H., Hamagaki H., UesakaT., Kubono S., “Simulation study of performance of active target GEM TPC”, at the 3rd Joint Meeting of the
APS Division of Nuclear Physics and Physical Societyof Japan, Oct. 14–17, 2009, Hilton Waikoloa Village,
Hawaii, USA.
Ideguchi E., “Lifetime measurements of RI beam andhigh-spin studies with degraded beams”, Workshop on
Physics Opportunities with GRETINA, Third Joint
Meeting of the Nuclear Physics Divisions of the APS
and JPS, October 13, 2009, Hawaii, USA.
Miya H., Shimoura S., Saito A., Miki K., Sasano M., ItohS., Itahashi K., Kawabata T., Shimbara Y., Yako K.,
Shimizu Y., Baba H., Kurei H., Michimasa S., NakanishiK., Noji S., Ota S., Sasamoto Y., Tokieda H., Uesaka
T., Sakai H., “Performance evaluation of Low Pressure
Multi-Wire Drift Chamber for RI beam” Third Joint
Meeting of the Nuclear Physics Divisions of the APS
and JPS, October 13–17, 2009, Hawaii, USA.
Go S., Shimoura S., Ideguchi E., Ota S., Miya H., Baba
H., “New method of digital pulse shape analysis of signals for segmented Ge detectors”, Third Joint Meetingof the Nuclear Physics Divisions of the APS and the
JPS, October 13–17, 2009, Hawaii, USA.
Tokieda H., Michimasa S., Ota S., Shimoura S., UesakaT., Noji S., Sakai H., Roussel-Chomaz P., Libin J-F.,
Gangnant P., Spitaels C., “Performance of Focal-Plane
Tracking Detector CRDC for SHARAQ”, Third Joint
Meeting of the Nuclear Physics Divisions of the APS
and the JPS, Oct. 13–17, 2009, Hawaii, USA.
Uesaka T., Nakanishi K., Kurei H., Ota S., Michimasa S.,
Saito A., Sasamoto Y,, Miya H., Tokieda H., ShimouraS., Miki K., Noji S., Sakai H., “Field mapping measurement of SHARAQ dipole magnets”, Third Joint Meeting- 487 -

6

of the Nuclear Physics Divisions of the APS and the JPS, Oct. 13–17, 2009, Hawaii, USA.
Sasamoto Y., Uesaka T., Kawabata T., Berg G.P.A.,
Nakanishi K., Noji S., Takeda H., Shimoura S., Sakai
H., “Ion optical studies in the high resolution beam line
and the SHARAQ spectrometer”, 3rd Joint Meeting of
the Nuclear Physics Divisions of the APS and JPS, Oct.
13–17, 2009, Hilton Waikooa Village, Hawaii, USA.
Yamaguchi H., Hashimoto T., Hayakawa S., Binh D.N.,
Kahl D., Kubono S., “Study on astrophysical reactions
using low-energy RI beams”, Workshop on Frontiers in
Nuclear Astrophysics I, Third Joint Meeting of the Nuclear Physics Divisions of the APS and JPS, October
13–17, 2009, Hilton Waikoloa Village, Hawaii, USA.
Wakabayashi Y., Yamaguchi H., Hashimoto T., Hayakawa
S., Kurihara Y., Binh D.N., Kahl D., Kubono S.,
Nishimura S., Gono Y., Suga M., Fujita Y., “Beta-decay
measurement of 46Cr”, at third joint meeting of the APS
and the JPS, Oct. 13–17, 2009, Waikoloa, Hawaii
Hayakawa S., Yamaguchi H., Hashimoto T., Wakabayashi
Y., Binh D.N., Kahl D.M., Kubono S., Iwasa N.,
Kume N., Miura Y., Teranishi T., He J.J., Kwon Y.K.,
Komatsubara T., Kato S., Wanajo S., “Direct measurement of the 11 C(α, p)14 N stellar reaction”, at 3rd Joint
Meeting of the APS Division of Nuclear Physics and the
Physical Society of Japan, Oct. 13–17, 2009, Hawaii,
USA.
Yoshida T., Kato K., “Algebraic N alpha model (applications for 12 C)”, at the APS and JPS meeting, Oct.
13–17, 2009, Waikoloa, Hawaii, US.
(国内会議)Conference)(Domestic
Hamagaki H., “A Critical Review of the Recent Resultsfrom Electro-Magnetic Measurements”, 12th Heavy Ion
Cafe, at the University of Tokyo, Tokyo, May 9, 2009.
Hamagaki H., “Discoveries of Hydro-Dynamical Behavior
in High-Energy Heavy-Ion Collisions”, 13th Heavy Ion
Cafe, at the University of Tokyo, Tokyo, Nov. 11, 2009.
Gunji T., “Development of W+Si Tracking Calorimeterand readout for LHC-ALICE”, at the Detector workshop
for RIBF experiments, Dec. 21–22, 2009, RIKEN, Wako,
Japan.
Gunji T., “東大 CNS における GEM 開発と Active Target
GEM-TPC の開発”, at the 6th Workshop on Micor Pattern Gas Detector, Dec. 11–12, Kobe University, Japan
Akimoto R., Ota S., Michimasa S., Gunji T., Yamaguchi
H., Hashimoto T., Tokieda H., Tsuji T., Kawase
S., Hamagaki H., Uesaka T., Kubono S., Isobe
T., Kawabata T., Ozawa A., Suzuki H., Nagae D.,
Moriguchi T., Ito Y., Ishibashi Y., Ooishi H., Abe Y.,“Design and performance of CNS active target TPC”
at the Detector workshop for RIBF experiments, Dec.
21–22, 2009, RIKEN, Wako, Japan.
Uesaka T., Akimoto R., Ota S., Michimasa S., Gunji T.,
Yamaguchi H., Hashimoto T., Tokieda H., Tsuji T.,
Kawase S., Hamagaki H., Kubono S., Kawabata T.,

Isobe T., Ozawa A., Suzuki H., Nagae D., Moriguchi
T., Ito Y., Ishibashi Y., Oishi H., Abe Y., KamiguchiN., “CNS active targets for Missing Mass Spectroscopy
with RI beams”, Detector Workshop for RIBF Experiments, Dec. 21–22, 2010, RIKEN, Saitama, Japan
Gunji T., “J/ψ Production in High energy heavy ion collisions at RHIC”, at the JPS Spring meeting, Mar. 20–23,
2010, Okayama University, Okayama, Japan.
Sano S., for the ALICE Collaboration: “LHC-ALICE 実験
おける粒子多重度測定” at the JPS Spring meeting, Mar.
20–23, 2010, Okayama University, Okayama, Japan.
Takahara A., for the PHENIX Collaboration: “Studyof J/ψ photoproduction in ultra-peripheral Au+Au
collisions at the PHENIX experiment”, at the JPS
Spring meeting, Mar. 20–23, 2010, Okayama University,
Okayama, Japan.
Akimoto R., Ota S., Michimasa S., Gunji T., Yamaguchi
H., Hashimoto T., Tokieda H., Tsuji T., Kawase
S., Hamagaki H., Uesaka T., Kubono S., Isobe
T., Kawabata T., Ozawa A., Suzuki H., Nagae D.,
Moriguchi T., Ito Y., Ishibashi Y., Ooishi H., Abe Y.,“Performance evaluation of active target GEM-TPC” at
the JPS Spring meeting, Mar. 20–23, 2010, Okayama
University, Okayama, Japan.
Tsuji T., Hamagaki H., Gunji T., Hori Y., Kistenev E.,
Chiu M., Sukhanov A., Seto R., “Study of basic properties of the Forward Calorimeter for PHENIX upgrade”,
at the JPS Spring meeting, Mar. 20–23, 2010, Okayama
University, Okayama, Japan.
Go S., Shimoura S., Ideguchi E., Ota S., Miya H., Baba
H., “New method of digital pulse shape analysis of signals from segmented Ge detectors by using moments”,
JPS Spring Meeting, March 20-23, 2010, Okayama University, Okayama, Japan.
Michimasa S., Tokieda H., Noji S., Ota S., ShimouraS., Uesaka T., Sakai H., Roussel-Chomaz P., Libin JF., Gangnant P., Spetaels C., “Performance of Detectors Installed at SHARAQ Final Focal Plane”, JPS
Spring Meeting, March 20-23, 2010, Okayama University, Okayama, Japan.
Kawase S., Ota S., Baba H., Shimoura S., Uesaka T.,“Performance Evaluation of Charge-to-Time-Converter(QTC)”, the 65th JPS Annual Meeting, Mar. 20–23,
2010, Okayama University, Okayama, Japan.
Ota S., Shimoura S., Aoi N., Takeshita E., Takeuchi S.,
Suzuki H., Baba H., Fukuchi T., Fukui T., HashimotoY., Ideguchi E., Ieki K., Iwasa N., Iwasaki H.,
Kanno S., Kondo Y., Kubo T., Kurita K., MinemuraT., Michimasa S., Motobayashi T., Murakami T.,
Nakabayashi T., Nakamura T., Niikura M., Okumura
T., Onishi T.K., Sakurai H., Shinohara M., SuzukiD., Suzuki M., Tamaki M., Tanaka K., Togano Y.,
Wakabayashi Y., Yamada K., “High Resolution Gammaray Spectroscopy of N=20 Neutron-rich Nuclei via Direct Reactions”, the 65th JPS Annual Meeting, Mar.

- 488 -

7

20–23, 2010, Okayama University, Okayama, Japan.
Miki K., Sakai H., Uesaka T., Baba H., Berg G.P.A.,
Fukuda N., Kameda D., Kawabata T., Kawase S., Kubo
T., Kusaka K., Michimasa S., Miya H., Noji S., OhnishiT., Ota S., Saito A., Sasamoto Y., Sasano M., ShimouraS., Takeda H., Tokieda H., Yako K., Yanagisawa Y.,
Yoshida A., Yoshida K., and , Zegers R.G.T., “Measurement of the the isovector spin monopole resonancevia the 208 Pb,90 Zr(t,3 He) reactions at 300 MeV/u”, atthe JPS Spring meeting, Mar. 20–23, 2010, Okayama
University, Okayama, Japan.
Suzuki T., “Beta decay modes of nuclei in the third peakregion of the r-process”, at the 65th JPS Annual meeting, Mar. 20–23, 2010, Okayama University, Okayama,Japan
Yoshida T., Kato K., Study of 12 C structure based on
Sp(2,R) algebra”, at the JPS meeting, Mar. 20-23, 2010,
Okayama University, Okayama, Japan.

- 489 -

8

TORIJIN

Oral Presentations(Todai-RIKEN Joint International Program for Nuclear Physics)(International Conference etc.)
N. Itagaki, “ Multi cluster correlations studied with

Publications

UCOM-like treatment”, First EMMI-EFES workshop on neutron-rich exotic nuclei “Realistic effective nuclear forces for neutron-rich nuclei” 9-11

[Journal](Original papers) *Subject to Peer Review
S. Aoyama and N. Itagaki, “Di-neutron correlationsin 7 H” Phys. Rev. C 80 rapid communication
021304 1-5 (2009).
T. Yoshida, N. Itagaki, and T. Otsuka, “Appearanceof cluster states in 13 C” Phys. Rev. C 79 034308
1-6 (2009).

Feb., GSI, Germany
N. Itagaki, “Cluster-like correlations in light nuclei”,
The 3rd LACM-EFES-JUSTIPEN workshop, 2325 Feb., Oak Ridge National Lab., USA
N. Itagaki, “Nuclear structure studies in JUSTIPEN
and EFES activities”, The 3rd APS-JPS meeting,
13 Oct., Big Island, Hawaii, USA

N. Itagaki and M. Kimura, “Cluster structure stabi(Domestic Conference)
lized by s2 neutrons in light neutron-rich nuclei”
N. Itagaki, “Exotic structure in the excited states ofPhys. Rev. C 79 034312 1-4 (2009).
neutron-rich nuclei”, 64-th Japan Physical Society
Y. Iwata, T. Otsuka, J.A. Maruhn, and N. Itagaki,
Meeting, Tokyo, Mar. 2009
“Synthesis of exotic nuclei in heavy-ion collisions
at higher energies” Eur. Phys. J. A 42 613-621(2009).

[Book Proceedings](Original papers) *Subject to Peer Review
M. Ito and N. Itagaki, “Covalent, ionic, and atomic
structures in 12 Be”, Int. J. Modern Physics Letters A 24 Issue: 11 1005-1008 (2009).
Makoto Ito and Naoyuki Itagaki, “Unified studies ofthe exotic structures in 12 Be and alpha+8 He scattering”, AIP Conf. Proc. 1098 231-236 (2009).
N. Itagaki, M. Kimura, M. Ito, S. Aoyama, and Y.
Hirata “Application of THSR wave function using
Monte Carlo technique” Int. J. Modern Physics
Letters A 24 Issue: 11 2019-2026 (2009).
Y. Iwata, T. Otsuka, J. A. Maruhn, and N. Itagaki“Reduced charge equilibration in heavy-ion collisions at higher energies” AIP Conf. Proc. 1098
308-312 (2009).

- 490 -

VII. LIST OF PREPRINTSRIKEN-NC-NP(2009 January ～ 2010 March)
1.

M. Yamagami, and Y. R. Shimizu, and T. Nakatsukasa “Optimal pair density functional for
description of nuclei with large neutron excess” January, 20092.

J. Gibelin, D. Beaumel, T. Motobayashi, Y. Blumenfeld, N. Aoi, H. Baba, Z. Elekes,
S. Fortier, N.
Frascaria, N. Fukuda, T. Gomi, K. Ishikawa, Y. Kondo, T. Kudo, V. Lima, T. Nakamura,
A. Saito, Y. Satou, J. -A. Scarpaci, E.Takeshita, S. Takeuchi, T. Teranishi, Y. Togano,A. M. Vinodkumar, Y. Yanagisawa, and K. Yoshida “Decay Pattern of Pygmy States Observedin neutron-Rich 26Ne” January, 20093.

T. Suda, M. Wakasugi, T. Emoto, K. Ishii, S. Ito, K. Kurita, A. Kuwajima, A. Noda, T. Shirai,
T. Tamae, H. Tongu, S. Wang, and Y. Yano “First Demonstration of Electron Scattering usinga Novel Target Developed for Short-Lived Niclei” February, 2009

4.

N. Imai, N. Aoi, H. J. Ong, H. Sakurai, K. Demich, H. Kawasaki, H. Baba, Zs. Dombradi,
Z. Elekes, N. Fukuda, Zs. Fulop, A. Gelberg, T. Gomi, H. Hasegawa, K. Ishikawa, M. Ishihara,
H. Iwasaki, E. Kaneko, S. Kanno, T. Kishida, Y. Kondo, T. Kubo, K. Kurita, S. Michimasa,
T. Minemura, M. Miura, T. Motobayashi, T. Nakamura, M. Notani, T. K. Ohnishi, A. Saito,
S. Shimoura, T. Sugimoto, M. K. Suzuki, E. Takeshita, S. Takeuchi, M. Tamaki, H. Watanabe,
and K. Yoneda

5.

“First lifetime measurement of 2+1 state in 12Be” February, 2009

S. Taakeuchi, N. Aoi, T. Motobayashi, S. Ota, E. Takeshita, H. Suzuki, H. Baba, T. Fukui,
Y. Hashimoto, K. Ieki, N. Imai, H. Iwasaki, S. Kanno, Y. Kondo, T. Kubo, K. Kurita,
T. Minemura, T. nakabayashi, T. Nakamura, T. Okumura, T. K. Onishi, H. sakurai, S. Shimoura,
R. Sugou, D. Suzuki, M. K. Suzuki, M. Takashina, M. Tamaki, K. Tanaka, Y. Togano, andK. Yamada “Low-lying states in 23Mg studied by proton inelastic scattering” May, 2009

6.

N. Hinohara, T. Nakatsukasa, M. Matsuo, and K. Matsuyanagi“Microscopic description of oblate-prolate shape mixing in proton-rich Se iostopes” June, 20097.

P. Doornenbal, H. Scheit, N. Aoi, S. Takeuchi, K. li, E. Takeshita, H. wang, H. Baba,
S. deguchi, N. Fukuda, H. Geissel, R. Gernhauser, J. gibelin, I. Hachiuma, Y. Hara, C. Hinke,
N. Inabe, K. Itahashi, S. Itoh, D. Kameda, S. Kannno, Y. kawada, N. Kobayashi, Y. Kondo, R.
Krucken, T. Kubo, T. Kuboki, K. Kusaka, M. Lantz, S. Michimasa, T. Motabayashi,
T. Nakamura, T. Nakao, K. Namihira, S. Nishimura, T. Ohnishi, M. Ohtake, N. A. Orr,
H. Otsu, K. Ozeki, Y. satou, S. Shimoura, T. Sumikama, M. takechi, H. Takeda, K. N. Tanaka, K.
Tanaka, Y. togano, M. Winkler, Y. Yanagisawa, K. Yoneda, A. Yoshida, K. Yoshida, and
H. Sakurai “Spectroscopy of 32Ne and the "Islamd of Inversion” June, 20098.

Y. Ichikawa, T. K. Ohnishi, D. Suzuki, H. Iwasaki, T. Kubo, V. Banerjee, A. Chakrabarti,
N. Aoi, B. A. Brown, N. Fukuda, S. Kubono, T. Motobayashi, T. Nakabayashi, T. Nakamura,- 491 -

T. Nakao, T. Okumura, H. J. Ong, H. Suzuki, M. K. Suzuki, T. Teranishi, K. N. Yamada,
H. Yamaguchi, and H. Sakurai“Berta decay of proton-rich nucleus 24Si and its mirror

asymmetry” July, 2009
9.

T, Inakura, T. Nakatsukasa, and K. Yabana “Self-consistent calculation of nuclear
photoabsorption cross section: Finite amplitude method woth Skyrme functionals in the threedimensional real space” July, 200910.

G. Watanabe, H. Sonoda, T. Maruyama, K. Sato, K. Yasuoka, and T. Ebisuzaki“Formation of Nuclear "Pasta" in Supernovae” July, 200911.

G. Watanabe “Efficient scheme for creating a maximally entangled state in a double-wellpotential” July, 200912.

G. Watanabe, F. Dalfovo, F. Piazza, L. P. Pitaeyskii, and S. Stringari“Gritical velocity of superfluid flow through single barrier and periodic potentials” July, 2009

13.

K. Matsuyanagi, M. Matsuo, T. Nakatsukasa, N. Hinohara, and K. Sato
“Open prblems in microscopic theory of large-amplitude collective motion” January, 201014.

K. sato, N. Hinohara, T. Nakatsukasa, M. Matsuo, and K. Matsuyanagi“A Model Analysis of Triaxial Deformation Dynamics in Oblate-Prolate Sgape Coexistence
Phenomena” January, 201015.

M. Matsuo and T. Nakatsukasa “Open problems in nuclear structure near drip lines”
January, 2010

CNS-REP
1.

Deuteron beam polarimeter in the Nuclotron ring and analyzing power for the d-p
elastic scattering at 880 MeV, T.Uesaka, K.Suda, P.K.Kurilkin, V.P.Ladygin, Yu.V.Gurchin,
A.Yu.Isupov, K.Itoh, M.Janek, J.-T.Karachuk, T.Kawabata, A.N.Khrenov, A.S.Kiselev,
V.A.Kizka, J.Kliman, V.A.Krasnov, A.N.Livanov, Y.Maeda, A.I.Malakhov, V.Matousek,
M.Morhach,, S.M.Piyadin, S.G.Reznikov, S.Sakaguchi, H.Sakai, Y.Sasamoto, K.Sekiguchi,
I.Turzo, T.A.Vasiliev, CNS-REP 79, May, 2009

2.

CNS Annual Report 2007, Edited by E. ideguchi, CNS-REP 80, Aug. 20093.

Computer Modelling of Electromagnetic Fields for RIKEN AVF Cyclotron, A. S. Vorozhtsov,
S. B. Vorozhtsov, JINR, Dubna, Russia, S. Watanabe, S. Kubono, CNS, University of Tokyo,
Japan, A. Goto, RIKEN Nishina Center, RIKEN, Wako, Japan, CNS-REP 82, June, 20

4.

CNS Annual Report 2008, Edited by S. Mitimasa, CNS-REP 83, Feb. 2010

- 492 -

VIII. LIST OF SYMPOSIA

(2009 April ～ 2010 March)
1. Arctic FIDIPRO-EFES workshop, Apr.20-24 2, Saariselka, Finland, University of Jyvaskyla,
TORIJIN
2. Mini Workshop「KbarN and its Few-Baryon Derivatives」May.11 Advanced Meson Science
Laboratory
3.

RIBF Mini Workshop「Electron scattering data needed for the charge-distribution
determination of unstable nuclei」 Ｍａｙ .14 RIBF Research Division

4.

RIBF Mini Workshop「One goal, different approaches - how to predict total reaction
cross sections」 Ｍａｙ .15 RIBF Research Division

5.

RIKEN Workshop「Mysteries of plant sexual differentiation」Jun.11 Radiation
Biology Team

6.

Joint Theory / Experimental Workshop「LHC@BNL」Jun.20 Joint Theory/Experimental

7.

"The 2nd Research Strategy Workshop「Nuclear data base in Japan -the nuclear energies in theuniverse and the earth」Jul.27-29 J.F.N.A."

8.

Joint Theory / Experimental Workshop「Early Physics at the LHC」Sep.2 Joint Theory/
Experimental Workshop

9. EFES Ab initio workshop, Oct.12 , Big Island Hawaii, USA, JUSTIPEN, TORIJIN10.

JUSTIPEN-EFES workshop on unstable nuclei, Dec. 7-9, RIKEN , JUSTIPEN, TORIJIN

11.

"RIKEN Workshop「Studies on mutagenic effect of heavy-ion beam using
model organizms II」 Dec.11

Radiation Biology Team & The Wakasa Wan Energy

Research Center "12. Joint CATHIE/TECHQM RIKEN Workshop 15-19 Dec. RIKEN/CATHIE/TECHQM
13. Detector Workshop for RIBF experiments Dec.21-22 Detector Team
14. RIKEN Lattice QCD Workshop Dec.22 Radiation Laboratory
15. RIKEN-TRIUMF collaborative workshop on nuclear theory, Dec.15-16 RIKEN Nishina
Center & TRIUMF
16.

RIKEN Symposium「Muon Science at the RIKEN-RAL Muon Facility 2009 」Jan.20-21
Advanced Meson Science Laboratory

17.

Mini Workshop「Study of the Superheavy Element at RIKEN」Jan.21 RIBF Research
Division18.

The decade of ion-beam breeding in RIKEN Jan.21-22 Radiation Biology Team19.

RIKEN Workshop on「Superheavy Element Chemistry」 Feb.2 Superheavy Element
Laboratory

20.

First EMMI-EFES workshop on neutron-rich exotic nuclei ``Realistic effective nuclear forces
for neutron-rich nuclei" Feb.9-11, GSI, Germany, EMMI, GSI, EFES

21.

Workshop for Orbital Angular Momentum (OAM) of nucleon Feb.12 Radiation Laboratory

22.

Workshop on Kaonic Nuclear Clusters Feb.16 Advanced Meson Science Laboratory- 493 -

23.

First EMMI-EFES workshop on neutron-rich exotic nuclei“Realistic effective nuclear

forces for neutron-rich nuclei” Feb.9-11, GSI, Germany, EMMI, GSI, EFES24.

The 3rd LACM-EFES-JUSTIPEN workshop, Feb.23-25, Oak Ridge National Lab., USA,
EFES, JUSTIPEN, Oak Ridge National Lab.

25. Japanese-French Workshop「EFES-LIA workshop on the Nuclear Energy Density Functional
Method」Feb.26-27 EFES-LIA
26.

CNS Workshop「EFES-LIA workshop on the Nuclear Energy Density Functional Method」
Feb. 26

27.

Fist LIA-EFES worksho“Low-energy collective motion of exotic nuclei”, Mar.2-4,

GANIL, France, LIA, EFES, GANIL- 494 -

IX. LIST OF SEMINAR

(2009 April ～ 2010 March)
Theoratical Research Division		
1 Elias Kiritsis (Physics Department, University of Crete, GR-71003, Heraklion,(REECE) Apr.3 ｢A holographic approach to
QCD」

2 Hidenori Sonoda (Graduate School of Science, Kobe University) Apr.10 ｢Quadratic divergences in the

Wess-Zumino model, revisited｣
3 T. Nakatsukasa(RIKEN Nishina Center) Apr.15 Colloquium「Symmetry breaking and phase transition in nuclei」
4 Takuya Kanazawa (Department of Physics, Graduate School of Science, The University of Tokyo ) May.8「Dense QCD in a finite volume」
5 Hideo Matsufuru (Computing Research Center, High Energy Accelerator Research Organization) May.15｢Lattice QCD simulation with dynamical overlap fermion｣
6 Tooru Yoshida (CNS, Univ. of Tokyo) May.27 13th Nuclear Theory Seminar「Appearance of cluster states in 13C」
7 Satoshi Yamaguchi (Seoul National University)

May.29「Surface operators and AdS/CFT correspondence」

8 Hans Feldmeier (GSI, YITP) Jun.8 14th Nuclear Theory Seminar「Shells, clusters, and halos - Concepts to solve
the nuclear many-body problem」
9 Shotaro Shiba (Department of Physics, Faculty of Science, University of Tokyo )Jun.12 「Dp-branes and U-duality from

BLG model」
10 Atsushi Mochizuki(RIKEN）Jun.17 Colloquium「Structure of regulatory networks and dynamics of bio-molecules」
11 Shinya Aoki (Univ. of Tsukuba) and others Jun.25-27「Structure of Nuclear Matter and Baryon-Baryon Interaction」
12 Makiko Nio (RIKEN Nishina Center) Jul.8 15th Nuclear Theory Seminar「Anomalous magnetic moments of the lepton」
13 So Matsuura (Department of Physics, Hiyoshi Campus, Keio University) Jul.13 ｢Instanton Counting and Dielectric Branes｣
14 Norihiro Iizuka (Kavli Inst. for Theoretical Physics, Univ. of California, Santa Barbara, USA) Jul.17「Matrix Quantum
Mechanics for the Black Hole Information Problem」
15 Takenori Furumoto (Osaka City Univ.) Jul.22 16th Nuclear Theory Seminar「Optical potential based on complex G-matrix
folding model - Important role of three-body force effect -」16 In Yong Park（Philander Smith College）Jul.24「Open string induced D-brane geometry: Two loop analysis」
17 Takeshi KOIKE (Department of Physics,Graduate School of Sience,Tohoku University. Jul.24「gamma-ray spectroscopy
of well deformed sd-shell hypernuclei」
18 Kazuhito Mizuyama (Univ. of Jyv_skyl_) Aug.3 17th Nuclear Theory Seminar「Microscopic description of the two-bodycorrelation density in the ground state and in the excited states of nuclei」
19 Makoto. Oka(TITECH) and others Aug.3-6 「Summer School on Exotic Nuclei」
20 Mitsutoshi Fujita (Department of Physics, Kyoto University) Aug.7「Eschenburg space as gravity dual of flavored N=4
Chern-Simons-matter theory」
21 Cristina Manuel (Instituto de Ciencias del Espacio (CSIC)) Aug.15「Cold Relativistic Superfluids: Transport Phenomena
and Applications」
22 Oleg Andreev (TU Munich and Landau Moscow) Aug.15「Searching for a mean string theory description of the puregauge theory in the IR」
23 "Hirotaka Hayashi (School of Science, the University of Tokyo) Aug.21「Codimension-3 Singularities and Yukawa
Couplings in F-theory」"
24 Edmond Iancu (IPhT, CEA Saclay) Aug.22「AdS/CFT and Heavy Ion Collisions」
25 Kazuhiro Sakai (Hiyoshi Department of Physics, Keio University) Sep.4 「Entanglement through conformal interfaces」- 495 -

26 Shinji Ejiri (Brookhaven National Laboratory, USA) Sep.7「 Study of the critical point in finite density lattice QCD」
27 Hitoshi Nakada (Chiba Univ.) Sep.16 18th Nuclear Theory Seminar「Self-consistent mean-field and RPA calculations withsemi-realistic NN interactions」
28 Takashi Okamura (Department of Physics, School of Science and Technology, Kwansei Gakuin University) Sep.25「Superfluidity of holographic superconductor models」
29 Simone Baroni (INT, Univ. of Washington and TRIUMF, JUSTIPEN guest) Oct.8 19th Nuclear Theory Seminar「Odd-evenmass staggering and nuclear superfluidity」
30 Jun Goryo (Department of Physics, Nagoya University) Oct.9「Chiral p-wave superconductivity」
31 Wen Wen-Yu (National Taiwan University, Taiwan) Oct.16 「Greybody factor in warped AdS3 black hole and its CFTinterpretation」
32 Hyun Seok Yang（KIAS）Oct.19「Anatomy of Spacetime」
33 Jnanadeva Maharana（Inst. Phys., Bhubaneswar）Oct.20「Toroidal Compactification of Type IIB Theory with Fluxes」
34 Robert Dijkgraaf（Amsterdam Univ.）Oct.27「Superconformal gauge theories, Liouville theory and matrix models」
35 Yutaka Okochi (Perimeter Institute for Theoretical Physics, Canada) Oct.27「On Confinement Index」
36 Katsushi Ito (Tokyo Institute of Technology, Department of Physics) Oct.27「Supersymmetric Gauge theories andInstantons IX」
37 Robert Dijkgraaf (Amsterdam Univ.) Oct.27「Superconformal gauge theories, Liouville theory and matrix models」
38 Jnanadeva Maharana (Inst. Phys., Bhubaneswar) Oct.27 「Toroidal Compactification of Type IIB Theory with Fluxes」
39 Goro Ishiki (CQUeST(Center for Quantum SpaceTime), Sogang University, Korea) Oct.3 「A novel large N reduction forgauge theories on 3-sphere」
40 Norihiro Iizuka (CERN, Switzerland) Oct.30「Exploring N-body Nuclear Force in Holographic QCD」
41 Yutaka Ohkochi (Perimeter Institute for Theoretical Physics) Oct.30 「On Confinement Index」
42 Nick Stephen Manton (Cambridge Univ.) Nov.2「Nuclei as quantized skyrmions」
43 Dominik Smith (Frankfurt Univ.) Nov.6 「Lattice simulation of a three dimensional effective theory for SU(2) Yang
Mills」
44 Yuri Aisaka (Instituto Fisica Teorica, Sao Paulo State University, Brazil)

Nov.13 「Some Recent Developments in PureSpinor Formalism」
45 Hiroshi Suzuki (RIKEN Nishina Center) Nov.18 Colloquium「Spontaneous breaking of supersymmetry 」
46 Toshio Nakatsu (Department of Mathematics and Physics, Setsunan University) Nov.20「Melting crystal, quantum torus
and supersymmetric Yang-Mills」
47 Ken'ichiro Nakazato (Kyoto Univ.) Nov.25 20th Nuclear Theory Seminar「Gyroid Phase in Nuclear Pasta」
48 Ryuichiro Kitano (Department of Physics, Tohoku University) Nov.30「Higgsinoless Supersymmetry and Hidden Gravity」
49 Raffaele Millo (University of Trento) Dec.3「Vacuum polarization and Strong CP-violation: from macroscopic effects tomicroscopic dynamics」
50 C.S. Lim (Department of Physics, Kobe University) Dec.5 「CP Violation in Higher Dimensional Gauge Theories」
51 Tatsuo Kobayashi (Graduate School of Science, Kyoto University) Dec.5「Extra dimensional models with magnetic
fluxes」
52 Yutaka Hosotani (Graduate School of Science, Osaka University) Dec.5「Stable Higgs bosons as cold dark matter in therealistic gauge-Higgs unification」
53

Yutaka Sakamura (Theoretical Physics Laboratory, RIKEN) Dec.5「Radius stabilization in gauge-Higgs unification」- 496 -

54 C.S. Lim (Kobe Univ.) Dec.5「CP Violation in Higher Dimensional Gauge」
55 Masatoshi TAKANO（Waseda University） Dec.21 「Variational calculations for the nuclear equation of state」
56 M. Takano (Waseda University) Dec.21 「Variational calculations for the nuclear equation of state」
57 Hidenori Sonoda(Kobe University) Jan.12 「A simple proof of the non-renormalization theorem for the Wess-Zumino
model」
58 Toshikazu Ebisuzaki(Riken) Jan.20 Colloquium「Gamma-ray Signal from Earth-mass Dark Matter Microhalos」
59 Masaya Kohda (Graduate School of Science and Engineering, Saitama University) Jan.29「The strongly coupled fourthfamily and a first-order electroweak phase transition」
60 Tetsuya Sakurai (Dept. of Computer Science, Univ. of Tsukuba)

Feb.10 21st Nuclear Theory Seminar「A Parallel

Eigensolver using Contour Integration for Large-Scale Scientific Computing」
61 Junya Yagi(Rutgers University) Feb.12 「Chiral algebras of (0,2) models: Beyond perturbation theory」
62 " Shinji Hirano (Niels Bohr Institute, Denmark)（Niels Bohr Institute） Feb.17 「Anomalous Charge Shifts in AdS(4)/CFT(3)」"63 Pascal Naidon (The University of Tokyo) Mar.18 「Efimov physics in cold atoms」
64 B. R. Barrett（Univ. of Arizona） Mar.26 22st Nuclear Theory Seminar Using the Concavity of Thermodynamical
Functions to Predict Nuclear Binding Energies (not open to the public)
65 "Takenori Furumoto (Osaka City Univ.) Jul.22 The 16th Nuclear Theory Seminar「Optical potential based on complex
G-matrix folding model- Important role of three-body force effect」"
66 Kazuhito Mizuyama (Univ. of Jyvaskyla) Aug.3 The 17th Nuclear Theory seminar「Microscopic description of the twobody correlation density in the ground state and in the excited states of nuclei」
67 Hitoshi Nakada (Chiba Univ.) Sep.16The 18th Nuclear Theory Seminar「Measurement of Low-mass Vector Mesons in HotMedium created by Relativistic Heavy-Ion Collisions」
		
Sub Nuclear System Research Division		
1 Julius Kuti (University of California, San Diego) Apr.9 ｢Nearly Conformal Gauge Theories and Compositeness at theLHC｣
2 Stefano Profumo (SCIPP, University of California, Santa Cruz ) Apr.10 ｢Fundamental Physics from the Sky｣
3 Mark Trodden (University of Pennsylvania) Apr.16「Constraining Interactions in Cosmology's Dark Sector」
4 Eugene Levin (Tel Aviv University) Apr.17 「Glauber-Gribov approach for DIS on nuclei in N=4 SYM」
5 Saul Cohen (JLab) Apr.30 「Electromagnetic Neutral-Meson Decays on the Lattice」
6 Urs Heller (APS/BNL) May.1 「Center Vortices, Confinement and Chiral Symmetry Breaking」
7 Ian Low (Argonne National Laboratory/Northwestern University) May.7「Implications of the Higgs Discovery in MS
8 Ayako Yamamoto（Magnetic Materials Laboratory,RIKEN) May.7「Variation of magnetic properties in metal complex
oxides with pyrochlore-type structure」
9 Matthias Burkardt (New Mexico State University) May.8 「Transverse (Spin) Structure of Hadrons」
10 Amarjit Soni (BNL) May.9 「``4th generation" and B-CP anomalies」
11 Matthew Reece (Princeton Center for Theoretical Science) May.21 「The AdS/QCD Correspondence: Still Undelivered」
12 Adrian Dumitru (Baruch College) May.28 「Gluon propagator and quarkonium decay width in a viscous QGP」
13 Eduardo Fraga (Rio de Janeiro Federal University) Jun.5 「Chiral symmetry restoration and strong CP violation in astrong magnetic background」- 497 -

14 D. A. Bryman (TRIUMF/University of British Columbia, Canada) Jun.5 「Rare opportunities: Seeking new physics
with rare decays of light particles」
15 Douglas Bryman (TRIUMF) Jun.5 「Rare opportunities: Seeking new physics with rare decays of light particles」
16 Nasser Demir (Duke University) Jun.6「Eta/s of a relativistic hadron gas from a hadronic cascade」
17 Miura Kohtaroh (Yukawa Institute for Theoretical Physics, Kyoto University) Jun.9 「Strong coupling lattice study in
QCD phase diagram and dense matter」
18 Marco Stratmann (Regensburg University) Jun.10 「The story behind a half - from current probes to future avenues」
19 Antonio Masiero (INFN/PADUA) Jun.12 「Flavor and SUSY: between frustration and hope」
20 Tim Tait (Argonne National Laboratory) Jun.18 「Academic Lectures, Top Quark Physics」
21 Giovanni Chirilli (Old Dominion University & JLAB) Jun.23 「Small-x Evolution of Structure Functions in the Next-toLeading Order」
22 Sebastian Klein (DESY) Jun.25 「Moments of the 3-loop corrections to the heavy flavor contribution to F2(x,Q2) for Q2>> m2」
23 Harutaka SAKAGUCHI (RCNP) Jul.3 「Neutron skin in 208Pb」
24 Gilad Perez (Weizman) Jul.8 「The inside and outside of top jets」
25 Thomas McElmurry (Madison) Jul.9 「Colored Scalars at the LHC」
26 Yasumichi Aoki (RBRC) Jul.10 「Non-perturbative renormalization in lattice QCD」
27 Chris Jackson (ANL) Jul.11「The WIMP Forest」
28 Kirill Tuchin (Iowa State University) Jul.17 「Coherence at high energies and J/Psi production」
29 Anastasios Taliotis (Ohio State University) Jul.18 「Applications of AdS/CFT in DIS」
30 Seung Lee (Weizman) Jul.23 「Anti-Matter Signals from Matter Stability (DM from RS-GUT @ Galactic Cosmic Rays
and LHC)」
31 LAURA REINA (FSU) Jul.25 「W/Z+b jets at hadron colliders: a challenging background」
32 Eduardo Ponton (Columbia University) Aug.6 「MSSM Higgs extensions: a model-independent approach」
33 Hye-Sung Lee (UC Riverside) Aug.8 「U(1)' instead of R-parity」
34 Shaouly Bar-Shalom (Technion, Haifa) Aug.13「Flavor Physics with Friedberg-Lee hidden symmetries & the case for theStandard Model with 4 families"」
35 Bowen Xiao (Lawrence Berkeley National Lab.) Aug.19「Polarized DIS and Spin Puzzle in AdS/CFT」
36 Jian Zhou (LBL, Berkeley & Shandong U) Aug.21「Azimuthal Ssymmetry in the Polarized Drell-Yan Process」
37 Emil Mottola (Los Alamos National Lab.) Aug.28「Systematics of High Temperature Perturbation Theory」
38 Kai Wang (University of Tokyo) Sep.17「Probing B/L Violation in the Extended Scalar Models at the LHC」
39 Gustavo Burdman (Sao Paulo/FNAL) Sep.24「Fourth Generation and Electroweak Symmetry Breaking」
40 Jens Braun (TRIUMF) Sep.25「Extreme limits of QCD: On QCD with many flavors or many colors」
41 Zhongbo Kang (RIKEN/BNL) Oct.2 「Some recent progress on single transverse spin asymmetry」
42 Sakai Nobuhiko(University of Hyogo)

Oct.5 「3D Momentum Density Distribution of Spins of Magnetic Electron ｓ in

Ferromagnetic Fe and Ni 」
43 Sergey Syritsyn (MIT) Oct.7 「Electromagnetic Form Factors of a Nucleon in Full Lattice QCD」
44 Sean Fleming (University of Arizona) Oct.22 「Top Jets & Precision Measurements of the Top Quark Mass」
45 Lev Lipatov Oct.29 「Integrability of high energy scattering amplitudes in multi-color QCD and N=4 SUSY」
46 Cecilia Lunardini (Arizona State University / RBRC) Oct.30 「Neutrinos from collapsing stars and future neutrino
telescopes」- 498 -

47 Jorge Noronha (Columbia Univ.) Nov.13 「Connecting Polyakov Loops to the Thermodynamics of $SU(N_c)$」
48 Aleksandr Azatov (University of Maryland) Nov.14 「Flavor physics of the scalar sector of the models with warped extra
dimension」
49 Aaron Pierce (University of Michigan) Nov.19 「Non-minimal Dark Matter--Nucleon Scattering」
50 Cai-Dian Lu (IHEP, Bejing) Dec.12 「Study of light scalar meson: four quark states and glueball possibility」
51 Kathryn Zurek (University of Michigan) Jan.7 「Dark Matter from the Baryon Asymmetry」
52 Ying-chuan Li (Univ. of Wisconsin, Madison) Jan.22 「EDM's & Bayrogenesis」
53 N. Arkani-Hamed (Institute for Advanced Study)

Jan.28 「N=4 SYM and the GrassmannianN. Arkani-Hamed (Institutefor Advanced Study)」
54 Jay Hubisz (Syracuse University) Feb.4 「Revealing Randall-Sundrum Hidden Valleys」
55 Yoshimasa Hidaka (Kyoto University) Feb.5 「Novel Diagrammatic Method for Computing Transport Coefficients」
56 Lance Dixon (SLAC) Feb.10「NLO QCD Predictions for Vector Bosons Plus Jets at the LHC」
57 Catalina Oana Curceanu （LNF-INFN,Italy）Feb.12「Exotic Atoms and Nuclei search at the DAFNE collider in Frascati」
58 Brent Nelson (Northeastern University) Feb.18「Nonuniversal Gaugino Masses, Dark Matter and the LHC」
59 Jan Pawlowski (University of Heidelberg) Feb.19「The QCD phase diagram: Results and challenges」
60 Andrea Ferroglia (Mainz University) Feb.25「Top-Quark Pair Production Beyond Next-To-Leading Order」
61 Sanjay Reddy (LANL) Feb.27「Transport and Screening in the Magnetized Neutron Star Crusts」
62 Jamie Gainer (Northwestern University and Argonne National Lab) Mar.4 「Supersymmetry without Prejudice」
63 Yamazaki Toshimitsu (RIKEN Nishina Center)Mar.5 「DDR (High Density Deuterium Reaction) Project 」

64 Antonio Delgado (University of Notre Dame) Mar.11 「Unitarity applied to hidden sector processes」
65 Masanobu Yahiro (Faculty of Sciences, Kyushu University )Mar.16 「Microscopic approach to reaction of unstable

nuclei (not open to the public) 」
66 Jesse Thaler (MIT) Mar.25 「Goldstini」
67 Yasushi Nara (Akita International University) Mar.26 「Eccentricity fluctuations and CGC」
		
RIBF Recearch Division 		1 "Yoichi Momozaki (Argonne National Laboratory) Apr. 27
RIBF accelerator seminar ｢Proper handling and safety of liquid lithium｣ "2 "Kimitoshi Kono (RIKEN) RIBF Accelerator Seminar Apr.21「Free surface of superfluid 3He」"
3 Hideyuki Sakai（Faculty of Science & Graduate School of Science, The University ）May.19 Colloquium 「--EPR paradox
and Bell's inequality test by pairs of two protons -- Einstein was wrong? --」4 Shunsuke Imanishi（National Institute of Vegetable and Tea Science,National Agriculture and Food Research Organization）
May.21 Radiation Biology Seminar「Isolation of heavy-ion induced mutant in M1 plant generation」
5 Morita Kosuke (RIKEN Nishina Center) May. 26 Nuclear Physics Seminar「Decay Properties of 266Bh and 262Db
Produced in the 248Cm + 23Na Reaction」」
6 "Toru Tamagawa (RIKEN) Jun.9
RIBF Nuclear Physics seminar「Observations of Supernova Remnants with the Suzaku X-ray satellite」"
7 Akira MIZUTA（Center for Frontier Science, Chiba University ）Jun.16「Nuclear Physics Seminar「Gamma-Ray-Burst Jet
from Collapsars｣」
8 Satoshi Sakaguchi（RIKEN）Jun.23 Nuclear Physics Seminar「Spin-orbit potential in neutron-rich helium isotopes」- 499 -

9 Yoshitaka KASAMATSU (RIKEN ) Jun.23 Nuclear Physics Seminar「Fluoro Complex of Element 105, Db」
10 Toshimi Suda(RIKEN) Jun.30 Nuclear Physics Seminar「First demonstration of electron scattering using a novel target
developed for short-lived nuclei- towards Hofstadter’s experiments for short-lived nuclei -」11 Markus Friedl（Inst. of High Energy Physics,Austrian Academy of Sciences）Jul.10「The Silicon Vertex Detector upgradefor Belle II」
12 Kaori Otsuki (Hokkaido Univ. Graduate School of Science, School of Science）Jul.14 Nuclear Physics Seminar「In quest of
the Origin of r-process elements
13 Erik Arner (RIKEN, Omics Science Center) Jul.17 Radiation Biology Seminar「Rice mutant re-sequencing mate pairanalysis」
14 Sasano Masaaki (Heavy Ion Nuclear Physics Laboratory) Jul.21 Nuclear Physics Seminar「Study of Gamow-Teller transition
strengths in the intermediate nucleus of the 116Cd double-beta decay by the 116Cd(p,n) and 116Sn(n,p) reactions at 300
MeV 」
15 Satoshi Chiba (Advanced Science Research Center, Japan Atomic Energy Agency) Jul.28 Nuclear Physics Seminar「Nucleardata research for nuclear energy and possible cooperations with nuclear and cosmo-nuclear physics」
16 Wayne M. Itano (National Institute of Standards and Technology, Boulder, CO USA) Aug.25 Nuclear Physics Seminar「Diamagnetic Shift of the Hyperfine Interaction in 9Be+ - Experiment and Theory 」
17 Gentaro Watanabe (RIKEN) Sep.8 Nuclear Physics Seminar「Formation of nuclear "pasta" in supernovae」
18 Umeya Atsushi (RIKEN) Sep.29 Nuclear Physics Seminar「Shell-model study on Lambda-Sigma coupling effect inneutron-rich lithium hypernuclei」
19 Hara (RIKEN) Oct.7 RIBF Accelerator Seminar「Calculation of Emittance in Aurora Storage Ring」
20 Thomas Schilcher(Paul Scherrer Institute (PSI)) Oct.16 RIBF Accelerator Seminar ｢Status of PSI Accelerators」
21 M. Broennimann (PSI）Oct.16 RIBF Accelerator Seminar「Status about RF activities at the PSI accelerator facilities」
22 A. Caruso (LNS/INFN) Oct.23 RIBF Accelerator Seminar「The radiofrequency system at INFN-LNS」
23 Christian Smorra (Mainz University, Germany) Oct.27 「TRIGA-TRAP: A double Penning trap mass spectrometer at the
research reactor TRIGA MAINZ」
24 "Yoshiyuki Aoki and Masataka Masuyama (Department of Monozukuri Engineering Aerospace engineering course
Tokyo Metropolitan College of Industrial Technology) Oct.27 Detector Team Informal Seminar「Development andevaluation of the wide dynamic range preamplifier for silicon sensor｣ "25 Naoto Nagaosa (Univ. of Tokyo) Oct.28 Colloquium「Symmetry and topology in multiferroics」
26 E. Donets（Dubna, Russia）Nov.5 RIBF Accelerator Seminar「ELECTRON STRING ION SOURCES APLIED FOR
FORMATION OF HIGLY CHARGED AND PRIMARY RADIOACTIVE ION BEAMS」
27 T. Hirano, Y. Kazama (RIKEN ) Nov.9 Radiation biology seminar「Frontiers of plant reproduction research」
28 Avraham Lalazar (Inst. of Plant Sciences）Nov.12「DET1 gene - good and bad aspects of pleiotropism」
29 "Tomoko. Abe(RIKEN ), Yoshiaki Nagamura (NIAS) Nov.24 Radiation biology seminar「Advancement of mutation
breeding technology in rice」"
30

H. Hosotani (Graduate School of Science, Osaka Univ.) Nov.24 Colloquium「What the Higgs boson really is like -fromsymmetry breaking to extra dimensions 」

31 Ken'ichiro Nakazato (Kyoto Univ..) Nov.25 Nuclear Theory Seminar「Gyroid Phase in Nuclear Pasta」
32 Hans Geissel (GSI) Nov.26 Nuclear Physics Seminar「Present and Future Experiments with Exotic Nuclei at GS」
33 " Andreas Adelmann（PSI）Nov.27 RIBF Accelerator Seminar「The Object Oriented Parallel Accelerator Library (OPAL),
Design, Implementation and Application」"- 500 -

34 "Hiromi Okamoto (Graduate School of Advanced Science
Matter, Hiroshima Univ.) Nov.30 RIBF Accelerator Seminar「Beam Cooling and Coulomb Crystallization」,「Space-Charge
Effectsin Intense Particle Beams」and「Phase-Space Manipulation by Means of Coupling Resona"
35 "Hiromi Okamoto (Graduate School of Advanced Science
Matter, Hiroshima Univ.) RIBF Accelerator Seminar「Non-neutral plasma and its experimental applications to beam
dynamics studies」"
36 Alexei A. Ogloblin (RRC Kurchatov Institute, Russia) Dec.7 Nuclear Physics Seminar「Measuring the radii of particle
unstable nuclear states and search for the signatures of alpha condensation in light nuclei」
37 Tatsuyuki Takatsuka（Iwate University）Dec.14 Colloquium「New nuclear-physics-problems addressed by neutron stars」
38 "Richard F. Casten（Yale U./JUSTIPEN Guest）Jan.6 RNC Lecture Series on Nuclear Physics Course VIII「Shell Model
and Collective Models in Nuclei: experimental and theoretical perspectives」"
39 "Tomonari Hirano, Yusuke Kazama(Riken), Yuko Odaira (Fukushima Pref. Soma High School) Jan.8 Radiation biology
seminar「Educational materials for genetics using Arabidopsis mutants II」"
40 Bikash Sinha（VECC, SINP Former Director) Jan.15「Accelerator based activities at VECC & SINP」
41 T. Kubo (RIKEN) Jan.19 Nuclear Physics Seminar「Overview of BigRIPS In-flight Separator at RIBF: Production and
Identification of RI Beams Using In-Flight Fission of a 345 MeV/u 238U Beam」
42 Heiko Scheitt (RIKEN) Jan.19 Nuclear Physics Seminar「Spectroscopy of 32Ne and the "Island of Inversion"」
43 Toshio Takeyumi（National Institute of Agrobiological Sciences）Jan.19「Evaluation of radiosensitivity (irradiation withgamma rays) in soybean 」
44 Carlo Barbieri (RIKEN) Jan.26 Nuclear Physics Seminar「Toward an accurate understanding of optical models and singleparticle states in exotic nuclei」
45

LIU Yong（IMP, Chinese Academy of Sciences）Feb.4 RIBF Accelerator Seminar「HIRFL-CSR STATUS AND
ACTIVITIES FOR FUTURE UPGRADES」

46 HE Yuan（IMP, Chinese Academy of Sciences） Feb.4 RIBF Accelerator Seminar 「Design of New LINAC Injector
for SSC of HIRFL」
47 C.Reed（ANL） Feb.8 RIBF Accelerator Seminar 「Development of the Liquid Lithium Thin Film Stripper and its
Electron Beam Film Thickness Monitor for FRIB」
48 Nobuo Hinohara (Theoretical Nuclear Physics Lab, Nishina Center) Feb.9 Nuclear Physics Seminar 「Microscopic
approach to large-amplitude collective dynamics in Se isot」
49 Yasutaka Taniguchi (RIKEN) Feb.9 Nuclear Physics Seminar 「Triaxiality of excited states in sd-shell nuclei」
50 C.Reed（ANL） Feb.9 RIBF Accelerator Seminar「Options for Beam-on-Film Testing of the FRIB Liquid Lithium
Stripper」
51 N. Hinohara (RIKEN) Feb.9 RIBF Nuclear Physics Seminar「Microscopic approach to large-amplitude collective
dynamics in Se isotopes」
52 Y.Taniguchi (RIKEN) Feb.9 RIBF Nuclear Physics Seminar「Triaxiality of excited states in sd-shell nuclei」
53 XU Zhe（IMP,Chinese Academy of Sciences）RIBF Accelerator Seminar「RF systen in the institute of modern physics」
54 Nakamura Takashi (Department of Physics, Tokyo Institute of Technology) Feb.23 Nuclear Physics Seminar「Halostructure and shell evolution studied by breakup reactions」
55 Giuseppe Verde（INFN, Catania）Mar.8 Heavy Ion Nuclear Physics Lab. Seminar「Correlation measurements in heavy-ion
collisions: probing dynamics and spectroscopy with unbound systems」- 501 -

56 N. Inabe (RIKEN) Mar.9 Nuclear Physics Seminar「Discovery of 42 new isotopes and 13 new isomer using 345 MeV/u U
beam with BigRIPS」
57 Maya Takechi (RIKEN) Mar.9 Nuclear Physics Seminar「Measurements of Interaction cross sections towards neutron rich
Ne isotopes at RIBF」
58 Tohru Motobayashi (RIKEN) Mar.30 Special Colloquium「Study of unstable nuclei with direct reactions」
CNS
1 "S. Ota (CNS, University of Tokyo), Jul.21 CNS Seminar,「Low-lying Proton Intruder State in $^{13}$B」"
2 "Y.~Tsuchimoto (CNS, University of Tokyo), Sep.8
CNS Seminar,「Measurement of Low-mass Vector Mesons in Hot-Medium
created by Relativistic Heavy-Ion Collisions」"
3 "S.~Romano (University of Catania), Dec. 17 CNS Seminar,「Recent results on the $^{10}$B(p,$\alpha$)$^7$Be and$^{11}$B(p,$\alpha$)$^8$Be reactions studied by means of the THM」"
4 "G.~Pizzone (INFN-LAS), Dec.17 CNS Seminar,「Effects of distortion of the intercluster motion in light nuclei」"
5 "S. Cherubini (University of Catania), Dec.17 CNS Seminar,「Nuclear Astrophysics at Catania」"
6 "S.~Amari (Washington University, St. Louis, USA), Mar.12 CNS Seminar,「Presolar grains from meteorites: a new window
to stars」"
7 "D. N.~Bihm (CNS, University of Tokyo), Mar.30 CNS Seminar,「The measurement of 21Na+alpha in inverse kinematics
and the 21Na(alpha,p) stellar reaction rate」"- 502 -AUTHOP INDEXABE Takashi

阿部喬

ABE Yasushi

阿部康志

ABE Tomoko

阿部知子

ADACHI Tadashi

46

BAUER Eric

251

23

BAUMGART Stephenvii, 277, 278, 279, 280,

BAZIN Daniel

281, 282, 283, 284, 285,

BEAUMEL Didier

287, 288

BEHR John

足立匡

253, 254, 255, 256

169

27

BENTZ Wolfgang

AIBA Takeshi

BERG Georg

AIHARA Toshimitsu

13
藍原利光

9

BEMMERER Daniel

ADELMAN Andreas 129
相場健201, 206, 208, 210

13, 1584

7, 169, 172, 191

114, 116, 117, 289,

BHANG Hyoung-Chan291

BINH Dam

30

AKASHIO Atsuko

赤塩敦子

297

BISHOP Shawn

AKIBA Yasuyuki

秋葉康之

65, 201, 202, 204

BLAU Dmitry

206, 208, 210

BLUMENFELD Yorick

AKIYAMA Takashi

秋山岳伸

27

AKIYAMA Kazuhiko

秋山和彦

AKOSHIMA Megumi

阿子島めぐみANDO Ryosuke

安藤良祐

ANDREICA Daniel
AOI Nori

青井考

AOKI Yoshiyuki
AOKI Sinya

86

22
217

AOYAMA Tatsumi

青山龍美

荒井亮一
新井一郎

ARIMA Akito

ASAHI Koichiro

11

CHARLES Pancake

208

CHEN JinGen

12, 19,CHEN RuiJiu

3

CHEN Alan

30

CHEN Jun

30
千葉好明

CHIBA Junsei

千葉順成

CHOI Seonho

崔善浩

268

CHOLLET Simon

202

CHUCK Pancake

204

66

56

旭耕一郎

浅井雅人

201

CHAKRABARTI Alok

105, 107, 109, 112

荒巻陽紀

有馬朗人

CIANCIOLO Vince
231, 16

CLOET Ianix, 268, 269

61

91

DALFOVO Franco

浅野大雅

62

DAM Binh

BABA Hidetada

BABA Yutaka

52

馬場秀忠

馬場裕

BAINES Christopher
BAKER PeterBARBIERI Carlo64, 6929, 31DANTSUKA Tomoyuki

段塚知志

DESÉRÉVILLE Nicolas

9x, 5, 6, 7, 8, 9, 12, 13,

DEGUCHI Shigeki

出口茂樹

15, 17, 18, 169, 191,192,

DELAUNAY Franck

10

199, 221, 222, 224,

DENIKIN Andrey

8

DESHPANDE Abhay

72, 201243

DINHDANG Nguyen

54

DOI Takumi

xx, 240, 241

土井琢身

DOMBRÁDI Zsolt

41

xiii

13, 15

DOORNENBAL Pieter-i-300, 304, 306

x, 5, 6, 10

97, 98, 99, 100

243, 250

BAKULE Pavel

201
大樂誠司

浅野克行

9

5, 6

84

ASANO Tomomasa
AVOGADRO Paolo

109

10

DAIRAKU Seishi

ASANO Katsuyuki
ASSIÉ Marlène

243

204

CHIBA Yoshiaki

184, 186

荒木幹生

ARAMAKI Yoki

91

88

新井重昭

ARAKI Mikio

ASAI Masato279

12, 17, 18, 19

10

CASSANO Nicole

xiii

青木和也

ARAI Shigeaki

蔡翔舟

CARTER Biggs

青沼航

ARAI Ichiro

11, 13, 15, 44

18, 19

AONUMA Wataru
ARAI Ryoichi

BROWN Alex

CARRETTA Stefano

182

243, 250

63, 72, 78

CAO Z

青木保道

9

BOYLE Kieran
CAI XiangZhou

253

青木保夫

AOKI Kazuya

70x, 4, 8, 10, 11, 12, 13, 14, 17,

青木慎也

AOKI Yasuo

256

34, 35青木義幸

AOKI Yasumichi

17, 18BLUNDELL Stephen

268

10

x, 4, 17, 18

DOZONO Masanori
DRAPIER Oliver
DRESS Axel

堂園昌伯

xi

201, 202

201, 202

DROUART Antoine

福田光順

3, 23

FUKUDA Hiroyuki

福田弘幸

297

FUKUDA Naoki

福田直樹

x, xvii, 3, 5, 6, 7, 11, 151

9155, 156, 157, 159, 161,DÜLLMANN Christoph
DUMITRU Adrian
DUPPEN PietFUKUDA Mitsunori

268

165, 169, , 302

89

FUKUNISHI Nobuhisa

福西暢尚

190

EBATA Shuichiro

江幡修一郎

51

135, 136, 184, 186,

EBISUZAKI Toshikazu

戎崎俊一

EISAKI Hiroshi

永崎洋

252

ELEKES Zoltán

13, 15EMOTO Takashi

江本隆

24

FÜLÖP Zsolt

EN’YO Hideto

延與秀人

1, 167, 201, 202, 204,iii

FURUKAWA Takeshi

191,282, 289, 291,
293
FUKUZAWA Seiji

福澤聖児

293, 289

13, 15
古川武

16, 18, 17, 190, 231,

206,208, 210

235

ENOMOTO Shuichi

榎本秀一

274

FURUKAWA Melissa

ENOMOTO Masaya

榎本真哉

242

FURUMOTO Takenori

ERIC Mannel

204

ETO Minoru

衛藤稔

EUGENE Shafto
EVEN Julia

古本猛憲

FURUTACHI Naoya

古立直也

GANGNANT Patrice

174

204, 208GASTALDI Franck

201, 202

GEISSEL Hans

江崎豊

FAMIANO Michael
FAN Fangli

196

92

269

EZAKI Yutaka

GERNHÄUSER Roman

274, 299

GIBBONS Gary

94

GIBELIN Julien

x, 10

5, 6

268

GILLIBERT Alain
GO Shintaro

FITRILAWATI

259

GOLOVKOV Mikhail 8

傅瑶5, 6, 163

8

GOTO Takayuki

後藤貴行

xix

9

GOTO Akira

後藤彰

125, 127, 136, 184, 186,
73, 78289, 291, , 293

243

GOTO Shin-ichi

12

GOTO Yusuke

藤井裕

248

GOTO Yuji

藤掛浩太郎

FUJIMAKI Masaki

藤巻正樹

235

後藤真一
後藤裕介

後藤雄二

GRUBER Bruno

123, 133, 135, 136,

GUILLOT Jacques

9289, 291

GUNJI Taku

82, 65

GUO Wei

HABA Hiromitsu

FUJISAWA Hiroshi

藤澤浩

FUJITA Mitsutoshi

藤田充俊

266, 267, 268, 272,

郭威

12, 19
羽場宏光

105272, 273, 274, 299,
HACHIUMA Isao

八馬功

HAGIWARA Shinichi

297

ix, 28, 230, 265, 266,
267, 268, 269, 270, 271,

95, 96279

73, 77, 78

56

郡司卓

藤沢弘幸

藤田新

191

69, 80, 167, 219

GROSSE-PERDEKAMP Matthias

FUJISAWA Hiroyuki

藤田尚子

28, 268

112, 116, 119, 121,

FUJINAWA Tadashi 藤縄雅 112, 142, 184, 186, 295

FUJITA Shinxvii, xv, 112, 119, 121, 123,240

FUJIKAKE Kotaro

FUJITA Naoko

199

郷農靖之

FRANCISCONI Patricia

FUJII Yutaka

郷慎太郎

GONO Yasuyuki

FRANCHOO Serge

FU Yaox241

FOMICHEV Andrey

FRANKE Isabel

62

9xv, 3, 16, 17, 18

FLEMING Donald

13, 15x, 3, 5266, 270, 271, 272, 273,

FANG Deqing

FRANCIS Prattxii, xv, 112, 119,
121, 123, 125, 131,x, 3, 5, 6, 23

萩原慎一

233

藤原康平

201, 202, 204, 206,

HAKI Yosuke

208, 210

HAMAGAKI Hideki

浜垣秀樹

65, 82

FUJIWARA Yuya

藤原裕也

216

HAMANAKA Makoto

濱仲誠289, 293

FUKAO Yoshinori

深尾祥紀

75, 76, 80, 228

HAMMACHE Fairouz

9

HARA Masahiroi, 144, 145

FUKAZAWA Hideto

深澤英人

252

- ii -

羽木洋介

201, 202, 204, 206, 208, 210

FUJIWARA Kohei

原雅弘

HARA Yuta

原裕太

x, 12, 17, 19

HARADA Toru

原田融

HASAMA Yuka

挟間優佳

HASEBE Hiroo

長谷部裕雄

HASEGAWA Taichi

HJORTH-JENSEN Morten

39

HONDA Takashige

16, 231xvii, 125, 289, 291, 293

長谷川太一

本多崇成

本間道雄

44, 45

HORI Toshitada

堀利匡

i, 144, 145

268

HORIBATA Takatoshi

橋本佳子

14

HU Zhengguo

12, 19HASHIMOTO Kimiaki

橋本公瑛201, 202, 204,

HUYSE Mark190

206, 208, 210

HYODO Toshio

橋本幸士

HASHIMOTO Yukio

ICHIDA Hiroyuki

51, 57

ICHIHARA Takashi

HASHIMOTO Takashi

橋本尚志

HASHIMOTO Tadashi

橋本直

HATA Maki

秦麻記

27

HATAKEYAMA Shin畠山晋

HATSUDA Yasuyuki

初田泰之

HATSUDA Tetsuo

29, 30, 31
191

277

初田哲男

93, 96

57

232

市田裕之

278

市原卓

5, 6, 167, 169, 221, 222

ICHIKAWA Yudai

市川裕大

26, 75ICHIKAWA Yuichi

市川雄一

11, 14, 16, 231

ICHIMIYA Ryo

一宮亮

IDEGUCHI Eiji

井手口栄治

IEKI Kazuo

xiii

堀端孝俊

兵頭俊夫

60, 83, 94

橋本幸男

12, 10, 17, 19

HONMA Michio

HASHIMOTO Yoshiko

HASHIMOTO Koji

45

201, 204, 206, 208

家城和夫

5, 6, 199

5, 6, 12, 17, 19, 18, 26

IGARASHI Kimie

五十嵐きみ江59

297

HATTORI Toshiyuki

服部俊幸

148

IIDA Kei

HAYAKAWA Kazuo

早川一生

231

IIJIMA Hiroaki

飯島裕章

16, 23191

IIMURA Hideki

飯村秀紀

20, 21

HAYAKAWA Masashi
HAYAKAWA Seiya

早川雅司

早川勢也

HAYANO Ryugo

早野龍五

HAYASHI Yoriko

林依子

HAYASHI Hironori
HAYASHI Tatuya

29, 30, 31

IIO Masami

191
16, 231

池田直美

229

IKEDA Yuki

HAYASHIZAKI Noriyosu

林崎規託

HEMMI Masatake

逸見政武

HERMANN Wollnik

20, 21HIDAYAT Rahmat
HIGAMI Naota

233

東山幸司

49, 50髭本亘

HIGURASHI Rieko

日暮（蛭沼）利江子

HIGURASHI Yoshihide

HINKE Christoph

251

池上祐司

204

IKEZAWA Eiji

池沢英二

105, 107, 112, 116, 119,

今井伸明

190

IMAJO Sohei

今城想平

26

日野原伸生

INAKURA Tsunenori

119, 121, 123, 133,

INOUE Takashi

289, 291, 293

INOUE Hirokazu

平岩聡彦

216

平山賀一
237

HIROI Masahiko

廣井政彦

257

稲倉恒法

27, 190

51

xiii

井上弘一
井上壮志

277
16, 231INOUE Rintaro

井上倫太郎

260

ISE Ryunosuke

伊勢龍之介

300, 304

ISHIBASHI Takuya

平山雄三

x, 5, 6, 151, 155, 156,

井上貴史

ISHIBASHI Nobuyuki

277, 280, 284, 285, 287

HIRAYAMA Yuzo

廣田誠子

40

94

平野智也

HIRAYAMA Yoshikazu

47, 48平林義治

稲辺尚人

159, 161, 163, 165, 169, 191

INOUE Takeshi

平野真司

HIRANO Tomonari

IMAI Nobuaki
INABE Naohito

日暮祥英 112, 114, 116, 117,HIRABAYASHI Yoshiharu
HIRAIWA Toshihiko

304

IKEGAMI Yuji297

x

HINOHARA Nobuo

HIYAMA Emiko

xiii

池上九三男

121, 123, 140, 291

樋上直太

HISAMATSU Toru

池田陽一

IKEGAMI Kumio

HIGEMOTO Wataru

HIROTA Seiko27, 75259

HIGASHIYAMA Koji

HIRANO Shinji

池田友樹

IKEDA Yoichi

136

264
33

IKEDA Naomi
148

池田時浩
池田清美

233

251

297

IKEDA Kiyomi

284, 283

HEFFNER Robert

216

飯塚里美

IKEDA Tokihiro

林祐子

HAYASHI Yuko

林達也

飯尾雅実

IIZUKA Satomi

vii, 278, 280, 281, 282, 287

林宏憲

飯田圭

石橋延幸

石橋拓也

ISHIBASHI Yoko

石橋陽子

ISHIDA Katsuhiko

石田勝彦

98, 99, 100

148

3, 12, 16, 19, 23
xx, 237, 238, 239,
240, 241, 262, 263,
264, 296

75

ISHIDA Takayuki

石田尚行

久松徹

257

ISHIHARA Masayasu

肥山詠美子

38

ISHII Kotaro- iii -

244

石原正泰

石井公太郎

279

10

ISHII Yasuyuki
ISHII Yasuo

石井康之

石井康雄

xix, 242, 244, 245, 246,

KAMIMURA Masayasu

252, 253, 257, 261,

KANADA-EN’YO Yoshiko

延与佳子

KANAI Yasuyuki

金井保之

20, 21, 201, 204, 206,

KANAYA Toshiji

金谷利治

260

268

ISHII Chihiro

石井千尋

5, 6

ISHII Tetsuro

石井哲朗

27

ISHII Yuji

石井祐司

ISHII Noriyoshi

KANAZAWA Mitsutaka

xiii

KANAZAWA Yuu

石川盛

ISHIKAWA Tomomi

石川智己

87

KANNO Shoko

ISHIMOTO Shigeru

石元茂

23

KANODA Kazushi

ISHIYAMA Hironobu

石山博恒

ITO Hiromasa
ITO Takashi

伊藤寛昌

302

251

ITO Makoto

伊藤誠

37

ITO Takuya

伊藤拓也

伊藤由太

ITOH Masatoshi
ITOH Satoshi

IWASAKI Masahikoxvii, 105, 107, 109, 111,
112, 116, 119, 121, 123,
140, 195, 229, 289, 291,
293, 295, 300, 304, 306

KATAYAMA Ichiro

12, 13, 15, 17, 18, 19, 29,

KATO Seigo

178, 180, 182

KATO Ken-ichi

岩崎弘典
252

出渕卓

IZUMI Masako

263, 264

KATO Tetsuya
KATO Reizo

泉雅子

9, 11, 14

20, 21, 190

29

加藤賢一

304, 306

加藤俊宏
加藤徹也

加藤礼三

KAWABATA Takahiro

240
249

245
川畑貴裕

x, 12, 14, 17, 18,
176, 178, 180, 192

87vii, 275, 276, 280

鄭淳讃

JIM LaBounty

204

KADOH Daisuke

加堂大輔

102, 103

影山正

KAWADA Yosuke

河田鷹介

KAWAHARA Tomomi

190

門野良典

x, 5, 6, 10

河原朋美

KAWAKAMI Satoshi

川上智

KAWAKAMI Rolandxx, 240

14, 197

278

261

KAWALL David

140, 289, 291, 293

KAWAMATA Takayuki 川股隆行 237, 238, 248, 249

71
253, 254, 255, 258,

29, 30, 31
加治大哉

147, 148

19, 31, 171, 172,JEONG Sunchan

KAGEYAMA Tadashi

KATO Toshihiro

柏木啓次

片山一郎

加藤静吾

216, 237, 239, 262,300

IYO Akira

KAJI Daiya

加瀬昌之

278

264

IZUBUCHI Takuix, 28, 265, 266,

125, 127, 135, 136, 138,

岩崎雅彦

岩崎健

xiv, 75

笠松良崇

14

IWASAKI Hironori

KAHL David

201, 204, 206, 208, 210

河西実希

KASE Masayuki

岩佐直仁

KADONO Ryosuke

唐津謙一

KASAI Miki

KASHIWAGI Hirotsugu

岩井良夫

250

KARATSU Ken’ichi

x, 169, 176, 191, 192

82

伊豫彰

x, 12, 17, 18, 19

鹿野田一司

3, 12, 19, 23,

井藤賀操

IWASAKI Ken

菅野祥子

271, 272, 273

IVANOV Marian
IWASA Naohito

25

264

267, 268, 269, 270,

伊藤正俊

伊藤聖

36

金末猛 146, 147, 148, 149, 286

KANESUE Takeshi

KASAMATSU Yoshitaka

84

ITOUGA Misao
IWAI Yoshio

190

x, 169, 176, 191, 192, 216

板橋健太

伊藤孝

ITO Yuta289, 293

金澤光隆

金澤悠

ISHIKAWA Shigeru

ITAHASHI Kenta

38

208, 210

16, 231

石井理修

上村正康

261

28, 30, 224, 265

KAJINAMI Yoshitomo

梶並佳朋

247

KAWAMURA Seiko

KAKUTANI Nobukazu

角谷暢一

302

KAWAMURA Hirokazu

KAMBARA Tadashi

神原正

KAMEDA Daisuke

亀田大輔

河村聖子

250

川村広和

16, 27229, 230, 232, 299

KAWANO Shigeyuki

河野重行

279, 285

3, 5, 6, 7, 27, 151, 155,

KAWASE Shoichiro

川瀬頌一郎

7, 169, 172, 176, 192

156, 159, 161, 165,

KAZAMA Yusuke 風間裕介 vii, 277, 278, 279, 280,
282, 283, 284, 285,

169, 191, 230
KAMIGAITO Osamu 上垣外修一

xvii, 105, 107, 109,

KEELEY Nicholas

9111, 112, 117, 119,KHASANOV Rustem

121, 123, 125, 135,KIDA Noriyuki

136, 289, 291, 293

KIDERA Masanori
KIENLE Paul- iv -

253

木田紀行

242

木寺正憲

191

116, 289, 291, 293

KIHOU Kunihiro

木方邦宏

252

KOURA Hiroyuki

KIKUCHI Yuma

菊地右馬33, 40

KOYAMA Ryo

KIKUCHI Takahiro

菊池貴宏

KRATZ Jens

268, 269

小浦寛之

小山亮

菊池晶浩

258

KRÜCKEN Reinerx

KIKUCHI Takashi

菊池崇志

184, 186

KRUPKO Sergei

8

KIKUCHI Yousuke

菊池彦光

KIKUNAGA Hidetoshi
KIKUTANI Yuki
KIM Aram

久保謙哉

261, 262

久保敏幸 x, 3, 5, 6, 7, 11, 20, 21,

KUBO Toshiyuki

3

菊永英寿

菊谷有希

KUBO Kenya

248

菊池陽介

135, 136, 195, 289, 293

268

KIKUCHI Akihiro

KIKUCHI Hikomitsu

28

265, 266, 267,

151, 153, 155, 156, 157,

268, 272, 274

159, 161, 163, 165, 169,
171, 172, 178, 180, 190,

266, 272

191, 230, 302

30

KIMURA Masaaki
KIMURA Hitomi

木村真明
木村仁美

KUBOKI Hironori

62

久保木浩功

xvii, 14, 125, 135,
289, 291, 293

12, 19KINOSHITA Norikazu

木下哲一

268

KUBOKI Takamasa

久保木隆正

KINOSHITA Toichiro

木下東一郎

91

KUBONO Shigeru

久保野茂

岸田隆

xvii

KISHIMOTO Isao

岸本功

v, 101KUDO Hisaaki
北本優介

KITATSUJI Yoshihiro
KITO Hijiri

KUBOYAMA Satoshi

13, 15KITAMOTO Yusuke
鬼頭聖

KOBAYASHI Kei

KUDOU Yuki

274

北辻章浩

270, 271, 272, 273
KUMAGAI Keiko

262, 231, 296

KUME Naoto

13, 15

190

熊谷桂子

久米直人

112, 123, 131, 289

17, 18, 29

KOBAYASHI Toshio

小林俊雄

10, 25, 178, 180

KURATA-NISHIMURA Mizuki

KOBAYASHI Takeshi

小林丈士

210

KUREI Hiroshi

榑井博

KURIBAYASHI Takahiro

KOBAYASHI Kiyoshi

小林清志

289, 293

KURIHARA Yuzo

KOBAYASHI Takumi

小林拓実

191

KURITA Kazuyoshi

KOBAYASHI Toru

小林知洋

小林徹

小濱洋央

小堀洋

KOIKE Shigetoshi
KOIKE Yoji

KOJIMA Norimichi
KOJIMA Takao

210
KURIYAMA Ai

小林 - 込山美咲

KOMORI Yukiko
KONDO Kotaro

KUROSAWA Maki

黒澤真城 201, 204, 206, 208, 210

KUSAKA Kensuke

日下健祐

KUZMIN Evgueni
LANTZ Mattias

x, 3, 23

265, 266, 267, 272

LAPOUX Valérie

9

LE Khiem

261

146, 147, 148, 149, 286

29

LEBEDEV Alexander

201
252

近藤崇

210

LEE Chul-Ho

KONDO Yosuke

近藤洋介

x, 4, 5, 6, 8, 10, 12, 13,

LEE Nam14, 15, 17, 18, 19, 178, 180

LEITGAB Martin

小高康照

康寛史

243, 250

278,

KONDO Takashi

KOU Hiroshi

x, 5, 6, 7, 116, 140, 151,

8LANCASTER Tom

246

小紫順治

KORSHENINNIKOV Alexey

8, 12, 17, 18, 19,

171, 178, 180, 191, 302

242

小松由佳梨

近藤康太郎

KOTAKA Yasuteru

266, 272

黒川明子

153, 155, 156, 157, 169,20, 21, 264

小森有希子

KOMURASAKI Junji

栗山亜依

KUROKAWA Meiko

169, 182

233

小松宏彰

KOMATSU-KATO Yukarii, 12, 17, 18, 19, 24,

59

小島憲道

KOMATSU Hiroaki

栗田和好

254, 255, 256

小島隆夫

274

201, 204, 206, 208,

252

小池茂年

小池洋二

196

30

232

112, 116, 123, 133, 289, 291, 293
KOHORI Yoh

栗林隆宏

栗原佑蔵

235

KOBAYASHI-KOMIYAMA Misaki
KOHAMA Akihisa

西村美月

169, 176, 192

KOBAYASHI Nobuyuki 小林信之 x, 5, 6, 10, 17, 18

KOBAYASHI Tomohiro

229

268
28, 265, 266, 267, 268,

工藤祐生

KUDRYAVTSEV Yuri

小林義男

小林圭

久保山智司

工藤久昭

269

252

KOBAYASHI Yoshio

11, 29, 30, 31, 127,
184, 186

KISHIDA Takashi
KISS Ádám

x, 3, 17, 18, 23

8LEVY Phil
289, 293

LI Zijie

216-v-

73, 7827

李子杰

LI KuoAng

李哲虎

30268, 269李闊昂

x, 4, 17

LI

Z

H

10

LIBIN Jean-François
LIU Yang

LOUCHEV Oleg
MA LiQiu

174

284
239

馬立秋

MA YuGang

277

3, 12, 17, 18, 19

MAIE Takeshi

眞家武士 112, 140, 289, 291, 293, 304

xi, 14

牧永綾乃

眞鍋葉子

MANIKONDA Shashi
MANION Andrew

MIYASHITA Yuki

62

宮下雄樹

27, 190

MIYAZAWA Kiichi

宮澤喜一

252

溝井浩

201
眞野大輔

水崎高浩

44, 45MOMOSE Takamasa

百瀬孝昌

241

森克仁

森善樹

233

300

MORIGUCHI Tetsuaki 森口哲明 3, 5, 6, 12, 19, 23,
MORIMOTO Kouji

MARÉCHAL François

9

MARQUES F.Miguel

10

MARTEL Ismael

232

森本幸司

28, 194, 224, 265

MORITA Kosuke

森田浩介

28, 194, 265, 270, 273

MOTOBA Toshio

元場俊雄

38

MOTOBAYASHI Tohru 本林透 x, 4, 5, 6, 8, 10, 11,
12, 13, 15, 17, 18, 19,8

MARUYAMA Toshiki

丸山敏毅

MASUYAMA Masataka
MATSUDA Yasuyuki

22, 178, 180, 182

iii

増山昌孝

182

MOUGEOT Xavier

9xx, 240, 241, 263,

MUKAI Hiroki

向井弘樹

297,

264

MUKAI Ryuji

向井隆司

287

9

松田恭幸

MATSUDA Yohei

松田洋平

25

MUKHA Ivan

MATSUE Hideaki

松江秀明

261

MURAKAMI Koichi

MATSUMOTO Takuma
MATSUO Masayuki
MATSUO Yukari

80, 219

184, 186

MANO Daisuke

松尾由賀利

MATSUURA Yuichi

MATSUZAKI Teiichiro

眞山圭太

MIBE Tsutomu

三部勉

25, 26, 75, 178, 180

18, 190, 235

MURANO Keiko

村野啓子

5, 6, 10, 17, 18,

MURATA Jiro

26, 157

MURAYAMA Hirohumi

47, 48, 235

村田次郎

MUTOH Hideaki

村山裕史

MYO Takayuki

明孝之

246, 260, 263,

NAGAE Tomofumi

264

NAGAE Daisuke

33, 34, 35, 40

永江知文
長江大輔

NAGAME Yuichiro

28

229
80
3, 16, 27, 184, 186,

永目諭一郎

NAGAMINE Kanetada

268, 269

永嶺謙忠

x, 9, 17, 30,

NAGANO Akira

169, 172, 174,

NAGASAWA Mitsuharu

永野章

176, 192

NAGASE Makoto

xx, 240, 263

230
長澤光晴

長瀬誠

245

289, 291, 293

NAGASHIMA Masayuki

長島正幸

3, 169, 192

7, 14, 169, 172, 176, 191,

NAGASHIMA Yasuyuki

長嶋泰之

232

192

NAGATANI Takeshi

長谷健

288

NAGATOMO Takashi

長友傑

231

三原基嗣

3, 231, 261

三頭聰明

光岡真一

274

27

NAIK Vaishali

11

NAKABAYASHI Takumi

8

宮裕之

xiii

26, 27, 75

武藤英明

237, 238, 245,

28

MITSUGASHIRA Toshiaki
MITTIG Wolfgang

12, 17, 18, 19, 182

村上哲也

道正新一郎

三木謙二郎

MITSUOKA Shinichi

村上浩之

MURAKAMI Tetsuya

75, 228MICHIMASA Shin'ichiro

MIHARA Mototsugu

MURAKAMI Hiroyuki

松崎禎市郎

MAYAMA Keita

98, 99, 100

62

松下昌史

松浦佑一

村上公一

47, 48松本琢磨

松尾正之

MATSUSHITA Masafumi

MIYA Hiroyuki

水頭慎一

72

MANNEL Eric

MIKI Kenjiro

5

MIZUSAKI Takahiro

MORI Yoshiki

5, 6

5, 10

宮武宇也

MORI Katsuhito

246

i

MIYATAKE Hiroari

MIZUGASHIRA Shin'ichi

前田幸重

MANABE Yoko

宮下裕次

MIZOI Yutaka

MAEDA Yukie

MAKINAGA Ayano

MIYASHITA Yuji

7, 169, 172, 176, 191, 192,

NAKAGAWA Itaru

199

NAKAGAWA Takahide

中林彩

中川格

11, 13, 15

75, 228中川孝秀

112, 114, 116, 117,MIYACHI Yoshiyuki

宮地義之

80, 219

119, 121, 123, 133,

MIYAHARA Naoaki

宮原直亮

27

289, 291, 293

MIYAMOTO Hiroshi

宮本寛

299

MIYASAKA Shou

宮坂翔

NAKAGAWA Mayu

80, 219- vi -

中川繭

281, 285

NAKAI Yoichi

中井陽一

26, 178

NITTA Minori

新田稔

27

NAKAMURA Takashi

中村貴志

20, 21NOBUTOKI Minoru

NAKAMURA Katsuro

中村克朗

75, 228,

NOJI Shumpei

野地俊平

NAKAMURA Masato

中村仁音138, 150, 304

NAKAMURA Tomoaki

中村智昭

167

NOLEN Jerry

5, 6

NAKAMURA Tota

中村統太

信時実

302

7, 14, 169, 171, 172, 174,
176, 192

249

NOMIYA Yoshio

野宮芳雄

NAKAMURA Hiroyuki

中村裕之

247

NOUICER Rachid

201

NAKAMURA Takashi

中村隆司

x, 5, 6, 8, 10, 11, 14,

NUGROHO Agung259

17, 18, 178, 180

ODASHIMA Yutaka

小田嶋豊

NAKAMURA Takeshi

仲村武志

289, 293

OGAWA Akio

NAKANISHI Kohsuke

中西康介

169, 176, 192

小川暁生

204

OGAWA Naruya

小川就也

NAKANO Takehito

中野岳仁

261

OGILVIE Craig

201

NAKANO Kenichi

中野健一

80, 219

OGIWARA Kiyoshi

荻原清

NAKANO Nobuo

中野信夫

232

OGLOBLIN Alexey

8

NAKANO Kazushiro

中野和城

NAKANO Eiji

仲野英司

NAKAO Taro

中尾太郎

NAKATSUGAWA Yohei

x, 5, 6, 11, 14

OHKI Tomonori

大木智則

289, 291

中津川洋平

OHNISHI Hiroaki

大西宏明

81, 216OHNISHI Jun-ichi

大西純一

xv, 112, 114, 116, 117,

27

中里仁

OHNISHI Tetsuya

大西哲哉

x, 3, 5, 6, 7, 151, 153,
171, 178, 180, 184, 186,

28

191, 222, 302

x, 3, 23OHSHIMA Masaya

231

南日卓

OHSHIRO Yukimitsu

268, 271

OHTA Shigemi

根村英克

NETTELETON Anthony

大島昌也

13, 15

南里朋洋

NEMURA Hidekatsu

289

3

波平晃佑

七尾翼

NANRI Tomohiro

10, 14

155, 156, 157, 165, 169,

生井沙織

NANNICHI Takashi

119, 121, 123, 178, 180,

中山佳晃

9

NANAO Tsubasa

79
47, 48, 51, 52, 58

中務孝

NALPAS Laurent
NAMIHIRA Kousuke

282, 283, 284, 285
xx, 240, 251, 252

NAKAZATO Hitoshi
NAMAI Saori

大部澄江

233

大石一城

中谷裕輔

NAKAYAMA Yoshiaki

OHBU Sumie27, 75

OHISHI Kazuki

NAKATSUKASA Takashi
NAKAYA Yusuke

297

92

太田滋生

OHTAKE Masao

xiii

304

大城幸光

x, 5, 6, 151, 155, 156,
159, 161, 169, 171, 302

5, 6
OHTANI Shunsuke

大谷俊介

202, 204

OHTSUBO Takashi

大坪隆

NIIKURA Megumi

新倉潤

OHYA Susumu

NIKOLSKII Evgenii

8

29
8

大矢進

OHZONO Hironobu

NINOMIYA Kazufumi

二宮一史

27, 75OISHI Hiroto

NINOMIYA Kazuhiko

二宮和彦

262

OKADA Kensuke

91

OKADA Kunihiro

西隆博

191

OKAMURA Kei

NISHIDA Minoru

西田稔

289, 293

仁尾真紀子

20, 21, 234
3, 5, 6, 23, 184, 186

263

大園浩之

大石寛人

NISHI Takahiro

NIO Makiko

30, 289, 293

85

大竹政雄

NICOLE Apadula

NGUYEN Tho

304, 306

73, 78229

12, 19岡田健介

12, 17, 18, 19, 70

岡田邦宏

19, 20, 21, 188, 190, 234

岡村圭

232

OKAMURA Hiroyuki

岡村宏之

OKAMURA Masahiro

岡村昌宏 146, 147, 148, 149,

xi, 9, 14

NISHIHARA Kiyoshi

西原潔284, 285, 277

NISHIKAWA Megumi

西川恵

271

NISHIMURA Shunji

西村俊二

x, 4, 5, 6, 8, 26, 30

OKUMURA Toshifumi

NISHIMURA Makoto

西村誠289, 293

OKUNO Hiroki

NISHIMURA Daiki

西村太樹

3, 23, 261

119, 121, 123, 125, 129, 138,

NISHINAKA Ichiro

西中一朗

268

140, 150, 178, 180, 289, 291,

NISHIO Masaki

西尾正樹

286
奥村俊文

奥野広樹

293, 300, 304, 306

271

NISHIWAKI Yoichi

西脇洋一

249

ONG Jin

NISHIYAMA Kusuo

西山樟生

261

ONISHI Takeo

大西健夫

11

ONISHI Junichi

大西潤一

27, 75NITTA Muneto

新田宗土

11

xv, xvii, 105, 107, 112, 116,

92

- vii -王惠仁11

ONUKI Yoshiyuki

小貫良行

201, 204, 206, 208, 210

SAKAKIBARA Hitoshi

榊原均

278

坂本久雄

297

OOE Kazuhiro

大江一弘

265, 266, 267, 268, 272

SAKAMOTO Hisao

OOE Masakazu

大江正和

288

SAKAMOTO Naruhiko

OOISHI Hiroto

大石寛人

3, 23

ORR Nigel

坂本成彦

xi, 105, 107, 109,
111, 112, 135, 136,
289, 291, 293,

x, 10

OSHIMA Masaya

大島昌也

SAKO Masami

300,

OTA Shinsuke 大田晋輔 7, 12, 17, 18, 19, 169, 172,174, 176, 192, 199, 222
OTOMO Hiromitsu
OTSU Hideaki

大友洋光

佐久間史典

3

櫻木千典

13, 15

180, 196

SAKURAI Hiroyoshi

櫻井博儀

大内田美沙紀12, 13, 15, 19, 26,178,

62

180, 184, 186, 196
67

268

應田治彦

216

SALMAN Zaher

243

SAMESHIMA Rei

鮫島玲

小山田和幸

289, 291

SANO Satoshi

佐野哲

OYAMATSU Kazuhiro

親松和浩

59

SASAKI Kenji

佐々木健志

PAK Robert

26, 75SANCHEZ-BENITEZ AngelOYAMADA Kazuyuki

小沢顕 3, 5, 6, 12, 19, 22, 23, 184, 186

OZEKI Kazutaka

x, 4, 5, 6, 9, 10, 11,

44, 45, 46

大塚直彦

OZAWA Akira

214, 216

佐久間収幸

大塚孝治

大浦泰嗣

SAKUMA Fuminori
SAKURAGI Yukinori

OUCHIDA Misaki
OUTA Haruhiko233

SAKUMA Kazuyuki

OTUKA Naohiko
OURA Yasuji

26

佐久間究

x, 5, 6, 8, 9, 10, 25, 178,

大津秀暁

OTSUKA Takaharu

229

酒向正己

SAKUMA Kiwamu

大関和貴 x, 25, 26, 28, 194, 265

SASAKI Tomoyuki

8

82
xiii

佐々木知之

SASAMOTO Yoshiko

302

笹本良子

7, 14, 169, 171,

201

172, 176, 192

PANCAKE Charles

201, 206

SASANO Masaki

笹野匡紀

xi, 7, 14, 169, 176, 192

PEARSON Matthew

27

SATO Kazuhiko

佐藤一彦

246

PEREPELKIN Evgeny
PIAZZA Francesco
PITAEVSKII Lev

127

佐藤雅志

PRATT Francis

25, 178, 180
9SATO Kiyokazu

xx, 241, 243, 250

SATO Hiromi

佐藤広海

157, 178, 180

SATO Koichi

佐藤弘一

48

268

QUANGHUNG Nguyen
RACHID Nouicer

21, 54

佐藤潔和

SATO Hidetaka

204

SATO Katsuhiko

254

佐藤勝彦

iii

9

SATO Wataru

RIEDLER Petra

201, 208

SATO Tetsuya

佐藤哲也

SATO Nozomi

佐藤望

259

ROUSSEL-CHOMAZ Patricia
SAITO Norihito

斎藤徳人

8, 9, 169, 174

佐藤渉

231, 261, 268
ix, 269, 268

ix, 28, 269

佐藤洋一 xv, 112, 116, 119, 121, 123

SATO Yoichi

239

SAWADA Shinya

澤田真也

SAITO Fuminori

斎藤文修

232

SCARPACI Jean-Antoine

SAITO Hiroyuki

斉藤宏之

288

SCHÄDEL Matthias

斉藤透

xi

SCHEIT Heiko

SAITO Akito

齋藤明登

7, 5, 6, 169, 171, 172, 176,

SCHEUERMANN Robert

191, 192

SCHUESSLER Hans

齊藤拓

齊藤直人

SAKA Takashi

坂貴75, 228

坂口治隆
坂口聡志

SAKAI Hideyuki

酒井英行

SAKAI Tadakatsu

酒井忠勝

SEIDL Ralf

車糸灰粉

25
xi, 14, 197

9x, 4, 17,258

20, 21, 234

20, 21, 188, 190, 226

73, 77, 78

SEITAIBASHI Etsuko

240,

SAKAGUCHI Harutaka
SAKAGUCHI Satoshi

SCHURY Peter

252

SAITO Naohito

80, 219

268

SAITO Tohru

SAITO Taku

302

佐藤秀孝

RAMUS Alexis
RISDIANA

281, 282

SATO Yoshiteru 佐藤義輝 x, 5, 6, 8, 10, 14, 17, 18,

61

POLLACCO Emmanuel
QIN Zhi

SATO Tadashi

61

聖代橋悦子

SEKIGUCHI Kimiko

関口仁子

SEKIMOTO Michiko

関本美知子

xi, 7, 14, 169, 171, 172,174, 176, 192
83

27xi, 14, 178, 180
201, 204, 206,
208, 210

SETOODEHNIA Kiana
SHAFTO Eugene- viii -30

201, 206

SHCHEPUNOV Viatslav
SHERRILL Bradley
SHIBATA Junsho

188

5, 6

柴田順翔

柴田利明

SHIBUKAWA Tomiko

渋川登美子

SHIGA Yuichiro

志賀雄一朗

SHIMADA Osamu

島田修

SHIMBARA Yoshihiro
SHIMIZU Yasuhiro
SHIMIZU Yohei

清水良文

SHIMODA Susumu

霜田進

169, 176, 192

58

204

鈴木謙

xx, 240, 261

191

鈴木謙介

SUZUKI Masaru

鈴木賢

11

SUZUKI Hiroshi

鈴木宏xi, 3, 8, 11, 23, 184, 186

SUZUKI Daisuke

鈴木大介

9, 11, 14

SUZUKI Tatsuo

鈴木達男

300

SUZUKI Hiroshi

鈴木都文
鈴木博

16, 231102, 103

田畑吉計

247

TACHIKAWA Maki

立川真樹

235

199, 222

TAI Ta-Sheng

戴大盛

95, 96, 97

265, 266, 267, 268,

TAJIMA Iwao

田島岩男

300, 304

269, 272, 274

TAJIRI Kunihiko

田尻邦彦

16

TAKADA Eiichi

高田栄一

26

TAKAGI Keiichi

高城啓一

vii

篠原摩有子
篠塚勉

14

190

12, 17, 18, 19

TAKAHARA Akihisa

252

TAKAHASHI Hironori

白石健一

白木一郎

254, 255, 256

TABATA Yoshikazu

篠原厚

SHIRAGE Parasharam

3, 5, 6, 17, 23, 184, 186

x, 10, 12, 17, 18, 19, 169,

SHINOZUKA Tsutomu

SHIRAKI Ichiro

鈴木健

232

171, 172, 174, 176, 192,

下浦享

SHIRAISHI Kenichi

SUZUKI Takeshi

SUZUKI Kunifumi

下村浩一郎

塩田良太

鈴木嘉昭

SUZUKI Kensuke

46, 250SHINOHARA Mayuko
SHIODA Ryota

14xi, 14, 169, 176, 192, 197

SHIMIZU Yoshifumi

SUZUKI Yoshiaki
SUZUKI Ken

新原佳弘

SHINOHARA Atsushi

xix, 242, 245, 248, 251,
258, 261

280

232

清水康弘

SHIMOURA Susumu

鈴木栄男

80, 219

島村智之

SHIMOMURA Koichiro

SUZUKI Takao

253, 254, 255, 256, 257,

229

清水陽平

12

289, 293SHIBATA Toshi-Aki

SHIMAMURA Tomoyuki

SUN Xiao-Yan

高原明久

68

高橋弘範

i

142

TAKAHASHI Katsuo

高橋勝緒

232

xx, 240

TAKAHASHI Naruto

高橋成人

266, 267, 272, 274

SHIRAKI Yasutsugu

白木恭嗣

TAKAHASHI Tomohiko

高橋智彦

v, 101SIDORCHUK Sergei

8

TAKAHASHI Yoshiyuki

高橋良幸

14

SIREGAR Rustam

259

TAKAHASHI Kazuya

SOHLER Dóra

10, 13, 15

SONDHEIM Walter

201

SONODA Hidetaka

園田英貴

SONODA Tetsu

園田哲

SORLIN Olivier

9

SPITAELS Charles
STEELE Andrew
STEFAN Iulian

5, 6

iii

高橋和也

高井茂臣

261

TAKAMINE Aiko

高峰愛子

20, 21, 188, 190

TAKASHINA Masaaki

20, 21, 188, 190

TAKAYAMA Reona

174
243

299

TAKAI Shigeomi

高階正彰

13, 15, 33, 40

高山玲於奈

266, 267, 272

TAKAYANAGI Toshinobu

高柳俊暢

TAKECHI Maya

3, 5, 6, 9, 23

武智麻耶

TAKEDA Hiroyuki

234

x, 5, 6, 7, 151, 155, 156,

竹田浩之

157, 165, 169, 191

9

STEPHEN Baumgart

TAKEDA Yoshikazu

204

竹田美和

258

TAKEDA Yuki

STRASSER Patrick

263

TAKEDA Hiroyuki

竹田浩之

3

STRINGARI Sandro

61

TAKEHARA Hiroki

竹原広樹

i

SUDA Kenji

14, 105, 107, 109, 111, 112,

TAKEHISA Hinako

竹久妃奈子

135, 289, 291, 293

TAKENOSHITA Yoshihisa

竹之下佳久

TAKESHITA Eri

竹下英里

x, 12, 19

TAKESHITA Nao

竹下直

252

須田健嗣

SUDA Toshimi

須田利美

i, 3, 8, 23, 24, 295

SUGAWARA-TANABE Kazuko

田辺和子

SUGIMOTO Shigeki

杉本茂樹

83

SUGINO Fumihiko

杉野文彦

SUKHORUKOV Oleksandr
SUMIKAMA Toshiyuki
SUMITA Takayuki

271

TAKETANI Atsushi

竹谷篤

TAKEUCHI Satoshi

武内聡

TAKEYAMA Mirei

武山美麗281, 282
288

80, 182, 201, 202, 204,
206, 208, 210, 219, 228

102
241

炭竃聡之

住田貴之

55, 56武田勇樹

240

STOYKOV Alexsay

x, 4, 8, 10, 12, 13, 15,
17, 18, 19, 222

x, 5, 6, 10

28, 194, 265- ix -

28

TAMAE Tadaaki
TAMII Atsushi

玉江忠明

民井淳

TAMURA Masashi
TAMURA Jun

24

TOYOSHIMA Atsushi

14

TSHOO KyoungHo

田村匡史

田村潤

豊嶋厚史

秋庚鎬

268, 269

10

114, 116, 117, 133,

TSUBAKIHARA Kohsuke

椿原康介

62

289, 291

TSUCHIHASHI Takahiro

土橋隆博

302

147, 148, 149

TSUCHIYA Masato

土屋真人

16, 231TANABE Kosai

田辺孝哉

55, 56

TSUKADA Kyo

TANABE Yoichi

田邉洋一

249, 253, 254, 255, 256

TSUKADA Teruyo

塚田晃代

vii, 276, 284

TANAKA Kana

田中佳奈

x, 5, 6, 10, 17, 18

TSUKADA Kazushi

塚田和司

27

塚田暁

81, 215, 216

TANAKA Shuuitsu

田中秀逸

277

TSUKADA Kazuaki

塚田和明

ix, 268, 269

TANAKA Hidekazu

田中秀数

xix

TSUKIORI Noritoshi

月居憲俊289, 293

TANAKA Toshiyuki

田中俊行

232

UCHIDA Makoto

TANAKA Kanenobu

田中鐘信

x, 3, 5, 6, 8, 13, 15, 17,

UCHIKOSHI Syouichi

23, 151, 155, 156, 159,

UCHIYAMA Akito

内山暁仁

161, 163, 169

UEMATSU Nobuya

植松暢矢

TANAKA Manobu
TANAKA Naoki

田中真伸

田中直樹

182

UEMOTO Ryuji

5, 6, 10UENO Hideki

TANAKA Hiroaki

田中裕彬

TANEJA Swadhin

63

TANIGUCHI Arisa

谷口亜梨沙

TANIGUCHI Yasutaka
TANIGUCHI Hiromi

93

内田誠

16

打越祥一

上本龍二

上野秀樹

UESAKA Tomohiro

116, 133, 289, 291
5, 6

230

5, 6, 16, 231
7, 14, 169, 171, 172, 174,

上坂友洋

176, 191, 192, 197
246

UJIHARA Tohru

宇治原徹

240

43

UMEYA Atsushi

梅谷篤史

39

246

UTSUNO Yutaka

宇都野穣44, 46谷口億宇

谷口弘三

TANIGUCHI Akihiro

谷口秋洋

263

UWAMINO Yoshitomo

上蓑義朋

TATSUNO Hideyuki

竜野秀行

191

VOROZHTSOV Alexey

127

VOROZHTSOV Sergey

127

TER-AKOPIAN Gurgen
TERANISHI Takashi
TERASHIMA Satoru
THOMAS Anthony

232

8

寺西高

11, 29, 31

VOSSEN Anselm

寺嶋知

25,

WADA Satoshi

73, 77, 78

和田智之

WADA Michiharu

84

297

239
20, 21, 188, 190, 226, 234,

和田道治

TIAN Wendong

12, 17, 18

WAKABAYASHI Yasuo

TIMCO Grigore

243

WAKASA Tomotsugu

若狭智嗣

xi

WAKASUGI Masanori

若杉昌徳

i, 24, 135, 144, 145,

x, 4, 8, 10, 12, 13, 15,

WAKI Takeshi

247

17, 18, 19, 178, 180, 182

WAKUI Takashi

涌井崇志

WANG Hex, 4

TJIA May

259

TODOROKI Koichi

轟孔一

TOGANO Yasuhiro

栂野泰宏

TOGASAKI Mamoru

戸ケ崎衛

若林泰生

29, 31, 30

184, 186

191

i

王赫

14, 190, 197

TOGASI Tomoaki

富樫智章

TOGAWA Manabu

外川学

TOKAIRIN Hideo

東海林英夫

TOKANAI Fuyuki

門叶冬樹

28, 224

WATANABE Gentaro

TOKIEDA Hiroshi

時枝紘史

7, 169, 172, 174, 176, 192

WATANABE Shizui

渡辺静意

210

TOKUDA Makoto

徳田真214, 216, 264

WATANABE Hiroshi

渡辺博

112, 119, 121, 123,

190

WATANABE Isao

渡邊功雄

xix, 237, 238, 242, 243,

TOM Harry62

和氣剛

WANG Jian-Song12, 17, 18, 19

69, 80, 201, 204, 206,

WANG Hong-Wei

12, 17 18, 19

208, 210

WANG Shuo

24

WANG Meng

12281, 282

渡辺元太郎

xx, 240TOMITA Hideo
TOMONO Dai

138, 195

富田英生

TOMITA Masanori

276

244, 245, 246, 247, 248,

216, 237, 238, 264

249, 250, 252, 253, 254,

冨田雅典

友野大

iii, 61TORII Chihiro

鳥居千寛

279

255, 256, 257, 258, 259,

TORIKAI Eiko

鳥養映子

xx, 240

259, 260, 261

TOUME Hayato

當銘勇人

268

WATANABE Yasushi

渡邊康

27

WATANABE Shin-ichi

渡邊伸一

TOYODA Takeshi

豊田健司

-x-

167, 221, 222
127, 195

WATANABE Susumu

渡邊進

WATANABE Yutaka

渡邊裕

300

YASUOKA Kenji

泰岡顕治

iii

矢崎紘一

84

27, 105, 112, 116, 119,YAZAKI Koichi

121, 123, 140, 190, 291

YOKAYAMA Akihiko

横山明彦

271
167, 212

WATANABE Hiroshi

渡邉寛

5, 6

YOKKAICHI Satoshi

四日市悟

WATANABE Tamaki

渡邉環135, 136, 289, 291

YOKOUCHI Shigeru

横内茂

WATANABE Noriaki

渡邉矩章xvii, 112, 119, 121, 123,

91

289, 291, 293

WENDONG Tian

19

YOKOYAMA Koji

WIECHULA Jens

82

YOKOYAMA Akihiko

横山明彦

WINKLER Martinx

YONEDA Ken-ichiro

米田健一郎

WINPENNY Richard

横山幸司

xx, 239, 240
268

243

x, 4, 8, 10, 12, 13,
15, 17, 18, 19, 25,

WOLLNIK Hermann

188

YABANA Kazuhiro

矢花一浩

51

YONEDA Akira

YADOMI Kazuyoshi

矢冨一慎

289, 293

YOSHIDA Kenichi

吉田賢市

xii, 42YOSHIDA Koichi

吉田光一

x, 5, 6, 7, 151, 155, 156,YAGI Eiichi

八木栄一

YAKO Kentaro

178, 180, 182

233

矢向謙太郎

xi, 14, 169, 192

山田基樹

159, 161, 169, 171,

山田文子

YAMADA Yutaka

山田豊

YAMADA Yusuke

山田雄介

YAMAGAMI Masayuki

222, 302

105, 107, 109, 111, 112,YOSHIDA Tomohiro

135, 136, 289, 291, 293

YOSHIDA Atsushi

吉田知紘

吉田敦

156, 169, 230, 302

xix

YOSHIDA Yutaka

吉田豊

204

YOSHIDA Shigeo

吉田茂男

287
5, 6

12, 17, 18, 19

山上雅之

YOSHII Hideakira

吉井秀彬

YOSHII Motoyasu

芳井基也寿
吉見彰洋

山口英斉

11, 29, 30, 31

YOSHIMI Akihiro

YAMAGUCHI Takayuki

山口貴之

5, 6, 23, 184, 186

YOSHIMURA Takashi

YAMAGUCHI Mitsutaka

山口充孝

8, 13, 14, 15

YOSHINAGA Kenta

YAMAGUCHI Yoshitaka

山口由高

6, 184, 186

YOSHINAGA Naotaka

山口頼人

YAMAGUCHI Takayuki

山家捷一

YAMAKI Tsutomu

八巻務

YAMAMOTO Yasuo

65

山口貴之

YAMAKA Shoichi

YOSHINO Akira
3

297
38

銭廣十三

山本浩史

245

ZHENG T

10

山本邦儀

300

ZHOU Pei

周培

山根功

150

YAMASAWA Hideyuki

山澤秀行

112

YAMAUCHI Hiromoto

山内啓資289, 291

YAMAZAKI Norio

山崎則夫

YAMAZAKI Yasunori

169

山崎泰規

YAMAZAKI Toshimitsu

20, 21, 264

山崎敏光

YANAGISAWA Yoshiyuki

柳澤善行

216
x, 5, 6, 7, 151, 153,
155, 156, 157, 169,
171, 172, 230, 302

YANG Jianjun

129

YANO Yasushige

矢野安重xvii, 24, 125, 184, 186,

YANO Yoshiyuki

矢野善之

229

YASUDA Yusuke

安田裕介

12, 19289, 291, 293, 302- xi -

12

5, 6, 1049, 50, 88

169

行平憲一

ZENIHIRO Juzo

YAMAMOTO Kuniyoshi

266, 267, 272, 274

吉永尚孝

7

YAMAMOTO Hiroshi

5, 6, 16, 231

吉永健太

ZEGERS Remco

ZHANG Guo-Qiang

233

吉村崇

吉野亮

YUKIHIRA Kenichi

293

山本安夫

231

58

YAMAGUCHI Hidetoshi

YAMAGUCHI Yorito

176

x, 5, 6, 7, 151, 153, 155,

xix

YAMADA Fumiko

YAMANE Isao28, 194, 265

山田一成 8, 11, 12, 13, 15, 17, 18, 19,

YAMADA Kazunari

YAMADA Motoki

米田晃

231

25
张国强 12

RIKEN Accelerator Progress Report vol. 43
独立行政法人理化学研究所加速器年次報告
印
発

刷
行

第43巻 (2010)平成22年（2010） 9月30日
平成22年（2010） 9月30日

発行者

独立行政法人理化学研究所
代表者

延〒351-0198

與

仁科加速器研究センター

秀人

埼玉県和光市広沢2番1号
電話 （048）462-1111

編集者

独立行政法人理化学研究所
加速器年次報告編集委員会

印刷所

株式会社デジタル印刷〒300-4405

仁科加速器研究センター

茨城県桜川市真壁町桜井307-1