UTTAC-82, 2013

UTTAC
ANNUAL REPORT 2012

TANDEM ACCELERATOR COMPLEX
Research Facility Center for Science and Technology
University of Tsukuba

http://www.tac.tsukuba.ac.jp/

UTTACANNUAL REPORT 2012
April 1, 2012 – March 31, 2013

UTTAC-82, 2013

Executive Editor: Eiji Kita
Editors: Hiromi Kimura, Daiichiro Sekiba, Kimikazu Sasa and Tetsuro Komatsubara

UTTAC is a series of issues, which include annual reports of
Tandem Accelerator Complex, Research Facility Center
for Science and Technology, University of Tsukuba.
Copyright © 2013 by Tandem Accelerator Complex, Research Facility Center
for Science and Technology, University of Tsukuba and individual contributors.
All reports are written on authors’ responsibility and thus the editors are not liable
for the contents of the report.

Tandem Accelerator Complex, Research Facility Center for Science and Technology,
University of Tsukuba
Tennodai 1-1-1, Tsukuba, Ibaraki 305-8577, Japan
http://www.tac.tsukuba.ac.jp/
annual@tac.tsukuba.ac.jp

PREFACE
This annual report covers research conducted at the Tandem Accelerator Complex,
Research Facility Center for Science and Technology, the University of Tsukuba, during fiscal
year 2012 (April 1, 2012–March 31, 2013). After the 12UD Pelletron tandem accelerator wascompletely destroyed by the Great East Japan Earthquake on March 11, 2011, research has been
limited to that using the 1 MV Tandetron accelerator and radiation source experiments, 57Co
Mössbauer spectroscopy, and positron annihilation spectroscopy. The circumstances of ourresearch have not changed much and are almost the same as those in the last fiscal year. Thus,
this volume has slightly fewer pages than older volumes.
We have started to reconstruct the main accelerator as a 6 MV tandem-type accelerator
with support from the government through the Ministry of Education, Culture, Sports, Scienceand Technology (MEXT), Japan. We have completed the plan and design for the new 6 MV
tandem accelerator, and it is being built by the National Electrostatics Corporation in Middleton,
Wisconsin, USA. It is expected to arrive at Tsukuba at the end of February or the beginning ofMarch 2014.
The efforts of Open Advanced Facilities Initiative supported by MEXT were continued inthis term, and the second stage was completed. The extension to the next step has been decided,
and, fortunately, the government will support additional facilities related to this program with an
extra budget. With this support, our performance on this program will be accelerated andbecome more active in the next fiscal year.
We are looking forward to operating and reporting on the new 6 MV accelerator.
Editors-i-CONTENTS

1. ACCELERATOR AND EXPERIMENTAL FACILITIES
1.1 Accelerator operation 2012.·································································· ·········

1

1.2 Status of the post-quake reconstruction project at UTTAC ······································

3

1.3 Measurement of the sign of the magnetic moment for proton by /2 pulse NMR methodwith rotating magnetic field ········································································ ···7

2. NUCLEAR PHYSICS
2.1 Investigation of Big Bang nucleosynthesis for solving 7Li problem ···························
30

28

3

30

9

2.2 In-beam -ray spectroscopy of P via the Si( He, p) P reaction ····························

11

2.3 Investigation of nuclear reactions for silicon burning around scandium-45 ···················

14

2.4 Measurements of nuclear moments for unstable nuclei in AVF, RCNP ·······················

16

2.5 Time resolution measurements for the time-of-flight detector in HIMAC ····················

18

3. MATERIAL AND CLUSTER SCIENCE
3.1 Zero Degree Electron Spectroscopy of 16 MeV C2+ Ions ·······································

21

3.2 Coincidence measurement of secondary electrons with scattered ions under irradiation of
fast carbon-cluster ions ···············································································

23

3.3 Detection of vacancy-type defects in InxGa1-xN alloys using a monoenergetic positron
beam ································································································· ···3.4 Site population of Fe ions in Mg-containing Fe3O4 nanoparticles determined by Mössbauer
spectroscopy ······················································· ······················ ··············
3.5 Development of E-E telescope ERDA detector ·················································

25
28
30

4. ACCELERATOR MASS SPECTROMETRY
4.1 Distribution of iodine 129 from the Fukushima No. 1 nuclear power plant accident ········

33

5. INTERDISCIPLINARY RESEARCH
5.1 Comparison of calibration curves for a new and old Si (Li) detectors with different energy
resolution ····················································································· ··········- iii -

35

6. LIST OF PUBLICATIONS
6.1 Journals ······························································ ····································

39

6.2 International conferences ··············································································

43

7. THESES ······································· ···························· ······································

47

8. SEMINARS ····································································································

48

9. SYMPOSIUM ·································································································

50

10. LIST OF PERSONEL·····················································································

52- iv -

1.
ACCELERATOR AND EXPERIMENTAL FACILITIES1.1

Accelerator operation 2012

K. Sasa, S. Ishii, H. Kimura, H. Oshima, Y. Tajima, T. Takahashi, Y. Yamato,
T. Komatsubara, D. Sekiba and E. Kita.
The University of Tsukuba Tandem Accelerator Complex (UTTAC) has operated and maintained the
1 MV Tandetron accelerator and the radio-isotope utilization equipment. In addition, the high resolution
RBS/ERDA accelerator was installed at UTTAC in 2012. At present, we are developing the 6 MV
Pelletron tandem accelerator instead of the broken 12UD Pelletron tandem accelerator which sufferedserious damage from the Great East Japan Earthquake on 11 March 2011. The 6 MV Pelletron tandem
accelerator will be installed and started formal operation in 2014.
The total service time of the UTTAC multi-tandem accelerator facility was 1,656 hours in the fiscal
year 2012. 336 hours for the 1 MV Tandetron accelerator and 57 days for the radio-isotope utilizationequipment were used for industrial users under the project "Promotion of Advanced R&D Facility
Utilization", which was supported financially by the Ministry of Education, Culture, Sports, Science andTechnology (MEXT) of JAPAN. In the project, a total of 16 research programs were conducted in 2012.
The 1 MV Tandetron accelerator
The operating time and the experimental beam time of the 1 MV Tandetron accelerator were 891.8
and 475 hours, respectively, during the total service time in 2012. A total of 55 research programs werecarried out and a total of 509 researchers used the 1 MV Tandetron accelerator. Figure 1 shows thepercentage of accelerated ions for the 1 MV Tandetron accelerator. 3He was mainly used for a low-energy
nuclear reaction for nuclear astrophysics. Figure 2 shows the percentage of research fields for the 1 MV
Tandetron accelerator.

Figure 1. Percentage of accelerated ions for the 1 MV Tandetron accelerator in 2012.

1

Figure 2. Percentage of research fields for the 1 MV Tandetron accelerator in 2012.

2

1.2

Status of the post-quake reconstruction project at UTTAC

K. Sasa, S. Ishii, H. Kimura, H. Oshima, Y. Tajima, T. Takahashi, Y. Yamato,
T. Komatsubara, D. Sekiba and E. Kita.
We are developing the post-quake reconstruction project to construct a new middle-sized tandem
accelerator instead of the broken 12UD Pelletron tandem accelerator since it is difficult to repair theprevious one due to some boundaries in the building construction. The accelerator system consists of ahorizontal type 6 MV Pelletron tandem accelerator, new 4 ion sources and the Lam-shift polarized ion
source (PIS), an accelerator mass spectrometry (AMS) system, ion beam analysis (IBA) systems and so on[1]. The PIS at the 9th floor of the building was damaged by the earthquake. After restoration of the PIS, it
will be moved from the 9th floor to a new experimental booth at the ground. A high energy beam transportline will be connected from the accelerator room to the present experimental facilities at the experimental
room. The magnets at the high energy side have a mass energy product of ME/Z2 = 176 amu MeV. The
beam transport line intersects with a new beam line for AMS and IBA at the accelerator room. The numberof 12 beam lines will be available for nuclear physics and ion beam applications. In 2012, we completed
the repair of the accelerator room. Figure 1 shows the photograph after the completion of renovation workon the accelerator room. Figure 2 shows the final layout of the 6 MV Pelletron tandem accelerator system.

Figure 1. Photograph of the accelerator room after the completion of renovation work.
The main accelerator, the model 18SDH-2 Pelletron tandem accelerator developed by National
Electrostatic Corp. (NEC), USA, is a dual acceleration (tandem) electrostatic accelerator. The accelerator
tank is designed as about 2.74 m in diameter and 8.77 m in length. The high voltage terminal has a longer
gas stripper tube assembly and a foil changer with a 48 foil holders for equilibrium stripping ions. The
stripper gas canal is about 10 mm in diameter and about 95 cm in length. The generator will operatereliably to terminal voltages as high as 6.3 MV. Figure 3 shows a layout of the main accelerator tank.
Figure 4 shows a photograph of the main accelerator tank under development at NEC, USA. The
accelerator will be capable of delivering up to 100 MeV for heavier ions. Maximum beam currents are
estimated at about 3 A for proton beam, and up to 50 A for heavy ions. Table 1 shows specifications of
the 6 MV Pelletron tandem accelerator.

3

Figure 2. Final layout of the 6 MV Pelletron tandem accelerator system.

1.75 m2.74 m8.77 mFigure 3. Layout of the model 18SDH-2 Pelletron accelerator tank.

4

Table 1. Specifications of the 6 MV Pelletron
tandem accelerator.
Accelerator tank size:
Length: 8.77 m
Diameter: 2.74 m
Beam line height: 1,775 mm
GVM and Slit current feedback system
Terminal stripper:
Gas (Ar or N2)
Foil unit (48 foil holders)Maximum Terminal Voltage: 6.5 MV
Maximum beam current:
H: 3 A
Heavy ions: ~50 A ( ~Au)

Figure 4. Photograph of the accelerator tank at NEC, USA.
Figure 5 shows the low energy side and ion sources for the 6 MV Pelletron tandem accelerator. Thereare 3 rotational 90 electrostatic cylindrical analyzers (ESA) and 5 ion sources. We are also planning toinstall a CO2 gas introduction system for one of the two MC-SNICS ion sources for 14C-AMS.

Figure 5. Low energy side and ion sources for the 6 MV Pelletron tandem accelerator.
In the field of nuclear physics, low-energy nuclear reaction, nuclear spin polarization and nuclear
astrophysics are available in the new accelerator system. The 6 MV Pelletron tandem accelerator will bealso applied to nanotechnology science, IBA, heavy ion irradiation and so forth. The rare particle detection
system will be capable of measuring environmental levels of long-lived radioisotopes of 10Be, 14C, 26Al,
36

Cl, 41Ca and 129I by AMS techniques. A 22.5° ESA with a 3.8 m radius is provided to filter out unwanted

ions for AMS. The 22.5° ESA has a resolution of E/E = 200. The rare particle detection system with a5

five-electrode gas detector for AMS is provided to measure the rate of energy loss in the gas for eachparticle entering the gas detector chamber. The IBA system has a high-precision five-axis goniometer for
RBS/ERDA and PIXE analysis. A micro-beam system will be equipped with Oxford OM2000 ion
micro-beam end-stage with a triplet quadrupole lens assembly on the 0º beam course at the accelerator
room. The micro-beam system is expected to focus ion beams less than 1 m and apply to micro PIXE
analysis and proton beam writing techniques. A charged particle irradiation equipment is mainly applied
for radio resistance tests of space-use devices.
The construction of the 6 MV Pelletron tandem accelerator system is scheduled in the spring of 2014.
The beam delivery will start on September 2014.
References[1] Kimikazu Sasa et al., AIP Conf. Proc. 1533, pp. 184-188; doi: http://dx.doi.org/10.1063/1.4806798.

6

1.3

Measurement of the sign of the magnetic moment for proton by p/2
pulse NMR method with rotating magnetic field

D. Nagae, T. Niwa, Y. Abe, Y. Ishibashi, and A. Ozawa
A rotating magnetic field has been developing [1] to determine a sign of magnetic (µ) moment by theb -ray detected nuclear magnetic resonance (b -NMR) method [2]. A producing of the rotating magnetic
field was achieved using an alternating current of about 5 MHz and two pairs of coils[3]. The measured
polarization of the rotating magnetic field of approximately 90% was sufficient to applying the NMR.
In order to investigate a perfomance of the rotating magnetic field, a measurement of the sign of theµ moment for proton (µ(proton) = +2.792847351(28) µN ) has been conducted by a p/2 pulse NMR
method.
The measurement was performed by using an about 9-MHz alternating current and a proton sample(H2 O). The production method of the rotating magnetic field was essentially the same as that described in
Ref.[1, 3]. A block diagram of the rotating magnetic field system and the p/2 pulse NMR system is shownin Fig. 1. The rotating magnetic field is obtained using two pairs of coils with axes crossed at right angles.
The coil radius and distance of a pair of coil are 20 mm and 24 mm, respectively. The phase angles of thealternating currents for the two pairs of coils were shifted by 90◦ . Thus the resulting magnetic field wascircularly polarized. By the adjustment of the phase-angle difference, a right- or left-circularly polarizedmagnetic field is produced. In order to obtained large polarized rotating magnetic field, amplitudes ofeach of the oscillating magnetic fields at resonance frequency were adjusted so as to make the outputsof a pickup coil equivalent. The crossed pair of coils and the proton sample were set at the center of astatic magnet. In the p/2 pulse NMR method, a NMR is measured by detection of a Free Induction Decay(FID) which arises non-equilibrium nuclear spin magnetization precessing about the magnetic field. This
non-equilibrium magnetization is induced by applying a pulse of resonant frequency of which direction issame as a Larmor precession of the nuclear spins. A static magnetic field of approximately 2.1 kG wasapplied to preserve a spin polarization with a direction from bottom to up. In this case, the FID signal is
Clock
Generator
Phase shi"er

Variable
capacitor

Duplexer

A!enuator
Sta#cmagne#c fieldFunc#on
RF-AMP
Generator

Cross
Diode
H₂O
Pre AMP
AMP
Oscilloscope

Phase shi"erPhase
Sensi#ve
Detector

Func#onGenerator

Fig. 1. A block diagram of the p/2 pulse NMR with rotating magnetic field.

7

obtained when a right-circularly polarized magnetic field is applied. The FID signal of which frequency
is same as a resonant frequency was detected by the pairs of coil, then the signal sent to a oscilloscopethrough amplifiers and a phase sensitive detector (PSD). A reference signal of which frequency was set as
9.00 MHz was provided by an another function generator and then was sent to the PSD via a phase shifter.
A phase of the reference frequency was adjusted so as to the FID signal was maximum. The measurements
were carried out in the following sequence. The rotating magnetic field perpendicular to the static field
was applied to the proton for a 55 µs duration using the pairs of coils. The FID was measured during thefollowing 1 s.
The FID signals obtained by applying left- and right-circularly polarized magnetic field are shown in
Fig. 2 a and b, respectively. The yellow and green signals indicate a FID signal and a start signal of rotating
magnetic field. In the FID signals, a noise might be due to the rotating magnetic field was observed.
Nevertheless, a larger FID signal is clearly observed when the right-circularly polarized magnetic field
was applied as shown in Fig. 2 b. Taking account of the direction of the spin polarization (bottom to up),it is successfully confirmed that the sign of the µ moment for proton is positive.

(a) left-circularly(b) right-circularly

Fig. 2. FID signals obtained by applying left- and right-circularly polarized magnetic field.

References[1] T. Niwa et al., UTTAC annual report 2011, UTTAC-81, 5(2012).
[2] K. Sugimoto et al., J. Phys. Soc. Jpn., 21, 213(1966)[3] D. Nagae et al., Hype. Int., 220, 65(2013).
[4] G.S. Bales et al., Phys. Rev., B50, 6057(1994).

8

2.
NUCLEAR PHYSICS

Investigation of Big Bang nucleosynthesis for solving 7Li problem

2.1

T. Komatsubara, T. Yuasa, T. Onish, K. Sasa, A. Ozawa, S. Okada, Y. Saito, T. Shizuma1, T. Hayakawa2, S.
Kubono2
One of the most important success for the theory of nucleosynthesis is the precise reproduction of themass abundance ration for helium-4 as 25% in the Big Bang nucleosynthesis (BBN) [1]. This achievement
can be one of the three proves of the existence of the Big Bang. Others are the red shift and the cosmic
microwave background. For the comparisons between the theoretical calculations and the observations,abundances of deuteron and helium-3 are also consistent. However, for litium-7 there is a large
discrepancy which the theory is three times higher than the observations [2] in spite of the resent
theoretical efforts [3]. Here, the observed abundance is referred from the plateau values in metal poor stars
reported by Spite [4] and/or Asplund [5]. In order to solve this large inconsistency, studies of the nuclear
reaction cross sections around the 7Li have been started. In the case of 7Li(3He, p0)9Be reaction theexperimental information is not sufficient between 0.1 and 0.4 MeV of the c.m. energy [6,7]. In this report,
our progress of the cross section measurements will be presented and shown as the astrophysical S-factor.
The measurements of the reaction crosssections have been performed at UTTAC byusing 1MV tandetron. An enriched 7Li target
was irradiated by 3He beam. The enrichment ofthe7

Li is 99%. The target was made byevaporation method of the metal on a carbon
substrate of 50 mg/cm2 thickness. The thicknessof the 7Li target is estimated to be 18.1±1.3
g/cm2 for 0.5 MeV measurement and 24.8±1.8
g/cm2 for others by comparison with theprevious report done by Sanada [8].
As the results of the experiments theFig. 1 Astrophysical S-factors for the 7Li(3He, p0)9Be

astrophysical S-factors are shown in figure 1.

reaction. Present results are shown as red circles. The

The present results are shown as red circles

Gamow window for BBN between 3 and 7 minutes iswhich correspond to Elab = 0.5, 0.6, 1.0, 2.0, 2.5

shown by the arrow. The green solid line shows the

MeV bombarding energies. The abscissa is theprevious interpolation done by Yan [6].

calculated

effectivec.m.

energies.

Black

triangles appearing around 0.1 MeV are the reported values by Yan [6], and the black circles above 0.4
MeV are by Rath [7]. The green solid line shows the previous interpolation by Yan [6]. The Gamow
1
2

Japan Atomic Energy Agency, Tokai, Ibaraki 319-1106, JapanRIKEN, Wako, Saitama 351-0198, Japan9

window which corresponds to the range between 3 and 7 minutes at BB is shown by the arrow. The
present result at Ec.m.=0.34 MeV is obviously lower than the previous interpolation. Then this results mightlead smaller destruction of 7Li.
Acknowledgment
We would like to express my gratitude for their helpful support by all staff and secretaries at the
University of Tsukuba, Tandem Accelerator Complex.

This work has been supported in part by

Grants-in-Aid for Scientific Research (21340068, 21540295, 24540298) of Japan.

References[1] R.V. Wagoner, Astrophysical Journal 148, 3 (1967) and D.N. Schramm, Review of Modern Physics, 70,
303 (1998).
[2] A. Coc, Physical Review D 65, 043510 (2002).
[3] M. Kusakabe, The Astrophysical Journal, 680, 846-857, (2008).
[4] F. Spite, Astronomy and Astrophysics, 115, 357 (1982).
[5] M. Asplund, The Astrophysical Journal, 644, 229-259, (2006).
[6] J. Yan, Physical Review C 65, 048801 (2002).
[7] D.P. Rath, Nuclear Physics A 515, 338 (1990).
[8] J. Sanada, J. Phys. Soc. Japan 26, 853 (1969).

10

2.2 In-beam g-ray spectroscopy of 30 P via the 28 Si(3 He, pg)30 P reaction
E. Mcneice1 , K. Setoodehnia1 , B. Singh1 , Y. Abe, D. N. Binh2 , A. A. Chen1 , J. Chen1 , S. Cherubini3 ,S. Fukuoka, T. Hashimoto2 , T. Hayakawa4 , Y. Ishibashi, Y. Ito, D. Kahl2 , T. Komatsubara, S. Kubono2 ,T. Moriguchi, D. Nagae, R. Nishikiori, T. Niwa, A. Ozawa, T. Shizuma4 , H. Suzuki, H. Yamaguchi2 ,T. Yuasa
30 P is an odd-odd self-conjugate nuclide, whose level density is reasonably high (34 proton-boundexcited states below S p = 5594.5(3) keV [1]) relative to that in the neighbor isobars. Isospin T = 0 and
T = 1 excited states coexist in 30 P from the ground state upwards. Such isospin symmetry breaking canchange the statistical distribution of electromagnetic transitions [2] and have a large impact on the levelstatistics [3]. Spectroscopy of 30 P thus provides an experimental test of the effect of isospin symmetry
breaking.
Despite several previous measurements [4], the g-ray transitions of several states in 30 P have neverbeen observed before, and many of the proton resonances with Ex > 5.7 MeV still have tentative spinparity assignments.
The 28 Si(3 He, pg)30 P reaction was the main background channel in an in-beam g-ray spectroscopy
experiment previously performed [5, 6] to investigate the level structure of 30 S populated via the 28 Si(3 He,ng)30 S reaction. Thus, we analyzed the existing data corresponding to the former channel to investigate
whether or not we could improve our understanding of the level properties of 30 P. We specifically aimed
to explore the region just above the proton threshold, where the g-rays from decays of a number of resonances whose excitation energies are near 6 MeV have never been observed before [4].
To carry out the original experiment, a 3 He2+ beam was accelerated via the tandem accelerator at
the UTTAC to 9 MeV and was impinged on a self-standing 25 µm-thick foil of natural silicon. The experiment consisted of two phases, which are explained in full details in Refs. [7, 8]. Our g-ray detector
setup consisted of two high-purity Ge-detectors located at 90◦ (phase I), and 90◦ and 135◦ (phase II) withrespect to the beam axis and on the opposite sides of the beam line. In each phase of the experiment, a g-g
coincidence matrix was produced and analyzed to obtain information on 30 P decay scheme.
In our g-ray angular distribution measurement, the intensities of the strong 30 P g-ray transitions observed in the singles spectra were normalized to the intense 677.1-keV 0+ → 1+ transition in 30 P. The

normalized relative yields for each peak of interest were plotted against the detection angle, and these data
were fitted using the Legendre polynomials. The g-g angular correlations of 30 P g-rays were determinedby measuring the directional correlations of oriented states for the strong 30 P g-ray transitions.
After placing software coincidence gates on the strong 30 P peaks observed in the singles spectra, decaycascades from higher-lying states were observed in the g-g coincidence spectra (see Fig. 1). By performinga least-squares fit to the recoil corrected g-ray energies, the 30 P excitation energies were reconstructed toobtain the level scheme of 30 P. For the sake of brevity, we have not shown the tabular results here. They
will be available online at the Experimental Unevaluated Nuclear Data List (XUNDL) database [10]. A
1 Department of Physics & Astronomy, McMaster University, Hamilton, ON L8S 4M1, Canada

2 Center for Nuclear Study, University of Tokyo, Wako Branch at RIKEN, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan
3 Dipartimento di Fisica e Astronomia, Università di Catania, Catania, Italy
4 Japan Atomic Energy Agency, Japan11

summary of our results will be published in Ref. [11].
We have observed for the first time 47 new transitions from 30 P excited states, most of which are proton resonances. Observation of these new transitions has enabled us to reduce the uncertainties (from 3 –10 keV down to < 1 keV) on the excitation energies of 17 states, denoted by † in Table 1 of Ref. [10], forwhich no g-ray transitions have been observed prior to the present work. Figure 1 presents a sample of thecoincidence spectrum obtained during phase I from a coincidence gate on a newly observed 1946.5-keV
peak, revealing several additional transitions from the 30 P excited states.
With the results of our g-ray angular distribution and g-g directional correlation measurements, wehave been able to confirm the previously determined spins of several states in 30 P. However, over all, ourdata are not adequate to assign firm spins to the other observed levels whose spin-parity assignments werepreviously determined to be tentative.

Figure 1: A sample of g-g coincidence spectrum measured at 90◦ obtained from gating on the 1946.5-keV(with J p = (6)+ → J p = 4− ) transition of 30 P, which is observed here for the first time. Peaks are labeledwith their energies (in keV) that are weighted averages between both phases of the experiment. The
1946.5-keV g-ray de-excites the 6178.50(17)-keV excited state of 30 P. Based on the results of Refs. [9,12], and those of the present work, we have assigned J p = (6)+ to this state. A recent shell model
calculation [13] predicts a J p = 5+ state within 100 – 200 keV from the 6178.50(17)-keV state observedin the present work. Our data do not rule out J p = 5+ (with the E1, M2 mixing ratio of d ≈ 0.5) for the6178.5-keV state.

References[1] G. Audi, M. Wang, A. H. Wapstra et al., Chinese Phys. C 36 1287 (2012).
[2] J. F. Shriner Jr., C. A. Grossmann, and G. E. Mitchell, Phys. Rev. C 62 054305 (2000).
[3] J. F. Shriner Jr., E. G. Bilpuch, and P. M. Endt, Z. Phys. A 335 393 (1990).
[4] M. S. Basunia, Nucl. Data Sheets 111 2331 (2010).
[5] K. Setoodehnia, A. A. Chen, T. Komatsubara et al., UTTAC Annual Report 2009, UTTAC-79 p. 9(2010).
[6] K. Setoodehnia, A. A. Chen, T. Komatsubara et al., UTTAC Annual Report 2010, UTTAC-80 p. 9
(2011).
[7] K. Setoodehnia, A. A. Chen, T. Komatsubara et al., Phys. Rev. C 83 018803 (2011).
[8] K. Setoodehnia, A. A. Chen, D. Kahl et al., Phys. Rev. C (submitted), arXiv:1210.1194 (2012).

12

[9] C. A. Grossmann, M. A. LaBonte, G. E. Mitchell et al., Phys. Rev. C 62 024323 (2000).
[10] Experimental Unevaluated Nuclear Data List: http://www.nndc.bnl.gov/ensdf/ensdf/xundl.jsp.
[11] E. Mcneice, K. Setoodehnia, B. Singh et al., Proceedings of International Conference on Nuclear
Data for Science and Technology, New York, March (2013).
[12] B. Ramstein, L. H. Rosier, and R. J. De Meijer, Nucl. Phys. A 363 110 (1981).
[13] Alex Browne, (private communication).

132.3 Investigation of nuclear reactions for silicon burning around scandium-45
T. Onishi, T. Komatsubara, A. Ozawa, K. Sasa, D. Izumi, M. Mukai, S .Kubono1,
T. Hayakawa2, T. Shizuma2
Elements up to iron are created by the burning process in star. There are various processes, but we took
an interest in silicon burning which is the final stage of nucleosynthesis in star. The silicon burning starts
from photodisintegration by high-energy gamma-ray and alpha-capture of silicon. Then, various elements
are created through quasi-equilibrium process. The reaction flow of quasi-equilibrium process is complex
and there are many reactions around scandium-45 [1]. The aim of our study is to measure reactions aroundscandium-45 which is known as a bottleneck in silicon burning. Woosly[1] pointed out that the flow isconcentrated to 42Ca(,p)45Sc and 45Sc(p,)46Ti reaction. In order to evaluate nuclear reaction rate of the42

Ca(,p)45Sc, we have performed measurements of the cross section and angular distribution for the

inverse reaction of 45Sc(p,)42Ca(Q-value = 2.34MeV). For this reaction, the experimental data werelimited only above 2.8MeV [2]. Therefore, we measured 45Sc(p,)42Ca reaction between 1.8MeV and
2.1MeV. This energy range corresponds to Gamow peak at a temperature of about 3GK in siliconburning. Also, we examine minutely the region between 2MeV and 2.1MeV in order to confirm whether
the resonance structure exists.
Our measurements were carried out by 1MV Tandetron accelerator at UTTAC. The accelerated proton
beam was irradiated on scandium target. The scandium target was prepared by evaporation in vacuum on
to 50 μg/cm2 crabon backing. The thickness of scandium layer was measured to be 42 μg/cm2.
Alpha-particle from 45Sc(p,)42Ca reaction was measured with E-Δ E counter by using SSD. We measured
detector angle with magnescale to evaluate angular distribution.
As a result, alpha-particle from 45Sc(p,)42Ca reaction was separately measured from strong elastic
scattering of protons by 45Sc layer and carbon backing. The yields of alpha-particle are corrected by deadtime of DAQ. The relation of the yield and the cross section is represented by following equation,

𝑌=𝑛

𝑁 𝑑𝜎
Ω
𝑆 𝑑Ω

where Y is yield, n is number of incident proton, N/S is particle area density of scandium45, dσ/dΩ isdifferential cross section and Ω is solid angle. The differential cross section is calculated by using thisequation.
Figure 1 shows angular distribution for differential cross section of 45Sc (p,α)42Ca reaction for 2MeV.
Differential cross section of forward angle seems to increase by contribution of direct component. We
think that of backward angle is compound component. We have compared the differential cross section
1

RIKEN,Wako, Saitama 351-0198, Japan

2

Japan Atomic Energy Agency, Tokai, Ibaraki 319-1106, Japan14

data at 130 for each energy and found the possibility of the existence of resonance structure. However,
we have not finished analyzing.
In future, we will calculate total cross section from angular distribution and evaluate astrophysicalS-factor. Furthermore, we will perform detailed analysis of resonance structure.

0.025

dσ/dΩ[mb/sr]

0.02

0.015

0.01

0.005

0
0

20

40

60

80

100

120

140

θcm[°]
Fig.1 Angular distribution of differential cross section for 45Sc(p,α)42Ca in CMS

References[1]S.E. Woosly, W. David Arnett, Donald D. Clayton, Astrophys J.S.231,26(1973) 231-312.
[2]J.S. Schweitzer, Z.E. Switkowaki, R.M. Wieland, NPA 287 (1977) 344.

15

160

2.4

Measurements of nuclear moments for unstable nuclei in AVF, RCNP

T.Niwa, Y.Abe, Y.Ishibashi, D.Nagae, S.Okada, A.Ozawa, K.Hatanaka1
By the Great East Japan Earthquake on Mar. 11, 2011, 12UD accelerator in UTTAC has been
completely destroyed and the experimental programs related to measurements of nuclear moments forunstable nuclei in UTTAC [1] has been stopped. In this situation, research center of nuclear physics(RCNP), Osaka University, offered to provide the machine-time which was terminated by the earthquake.
We accepted this support and started to build our experimental apparatus for -NMR system, which can beused for measurements of nuclear moments for unstable nuclei, in AVF facility, RCNP from 2012. In thisreport, we will introduce the apparatus built in AVF, RCNP, and show preliminary results for the
performance test using the apparatus.
Experimental apparatus, which we built in AVF, RCNP, is shown in Fig. 1. A NMR magnet, which was
newly constructed by using the reconstruction budget through the Ministry of education, Culture, Sports,
Science and Technology Japan, was transported from Tsukuba to RCNP. The connection part from AVF
cyclotron to a NMR chamber located in the center of the NMR magnet was built by RCNP. The NMR
chamber and the detectors to measure the -rays are reused in those used in UTTAC [1].
The performance check of the apparatus was done in July, 2012. We performed a measurement of themagnetic moment of 24mAl (I=1+, T1/2=131.3 ms) by using this apparatus. The magnetic moment of 24mAlr

has been measured in HIMAC, NIRS [2]. The nuclear polarized 24mAl has been produced by the 24Mg( p ,n)24mAl reaction with a polarized proton beam. The proton polarization was optimized by using a simple
polarimator made of two plastic scintillators located at the down stream of the NMR chamber (see Fig. 1).

 can also
The primary proton beam energy was 53 MeV and the intensity was 16 nA. A target, whichbecome a stopper for the recoiled 24mAl, was a MgO crystal (0.5 mm thickness). -rays emitted from thepolarized 24mAl were measured by two sets of beta-ray telescopes located above and below of the stopper.
Each set of the telescope consists of two thin plastic-scintillators (1 mm thickness), a Cu absorber (1 mmthickness) and a thick plastic-scintillator (10 mm thickness). Observed time-spectrum of the -rays
confirmed the 24mAl production in the target. Preliminary observed -NMR spectrum is shown in Fig. 2,
where the magnetic field of the NMR magnet was set to be 2.413 kG. This magnetic field corresponds to
5.5 MHz Larmor-frequency for 24mAl. We observed about -0.4% effective asymmetry for 24mAl.
As the summary, we built the -NMR apparatus in AVF facility in RCNP, which is a part of the
support program for the Great East Japan Earthquake in RCNP. The preliminary measurement for themagnetic moment of 24mAl shows that the present apparatus can be used for the measurements of nuclear
moments for some unstable nuclei by the -NMR method. Thus, by using the apparatus, we will continue
the experimental programs performed in UTTAC.

1

RCNP, Osaka University

16

Fig.1 A side view of experimental apparatus built in AVF, RCNP. A MgO target (stopper) is located in the
middle of the NMR chamber.

0.8

Effective asymmetry (%)

0.6
0.4
0.2
0
-0.2

RF off

-0.4
-0.6
-0.8
4.8

5

5.2

5.4

5.6

5.8

6

6.2

6.4

RF (MHz)

Fig. 2 Frequency dependence of the effective asymmetry for 24mAl observed in our apparatus. Open circle
corresponds to the data without RF. Arrow corresponds to Larmor frequency of 24mAl with 2.413 kG
magnetic field.
References[1] Y.Ishibashi et al., UTTAC ANNUAL REPORT 2010 (2011) 17. and References therein.
[2] D.Nishimura et al., Hyperfine Int. 180 (2007) 71.

17

2.5

Time resolution measurements for the time-of-flight detector in
HIMAC

S. Okada, D. Nagae, A. Ozawa, Y. Ishibashi, Y. Abe, S. Fukuoka, R. Nishikiori, T. Niwa, Y. Saito,
N. Inaba, S. Aldyyarov, K. Sawahata
The precision mass measurement system of rare RI beam is proposed at RIKEN RI beam factory (RIBF)[1]. In this plan, the masses are deduced from a time-of-flight (TOF) of RIs in the ring. Details of a principle of a mass measurement are described elsewhere [2]. In order to determine masses with a precision of
10-6, a time resolution less than 100 ps is needed. A dedicated TOF detector using a micro channel plate(MCP) and a carbon foil has been developed (MCP-TOF) [3]. A schematic view of the MCP-TOF isshown in Fig. 1. A principle of the MCP-TOF is explained in Ref. [3]. The size and thickness of the carbon foil is 100 mm  50 mm and 60 g/cm2. Nine electrodes which are connected 2.2 Mresisters at 5.0
mm intervals are installed in the MCP-TOF to create a uniformed electric field. To make a magnetic field,
two coils are placed both side of the MCP-TOF. To achieve of isochronous condition for electron is emitted from the carbon foil, the relation between the electric (E), and the magnetic (B) fields and a lateral displacement of the secondary electrons (D) is given by [4]
D=

2m E
q B2

where m and q denotes a mass and a charge of electron, respectively. In the case of the present MCP-TOF,
the lateral displacement and the electric field are set at D = 140 mm and E = 60 V/mm, thus the magnetic
field is calculated to be B = 39.1 G. To obtain good time resolution, it is important that good homogeneous
magnetic and electric fields.
In this work two modifications were made to obtain homogeneous magnetic and electric fields. Concerning of the magnetic field, the number of right coils was adjusted from 100 turns to 94 turns. In thisadjustment, an inhomogeneity of the magnetic field was reduced from 15% to 7%. For the electric field, aground electrode which is opened on one side was replaced to a full opened one with grids made of Au +W wire with a diameter of 12 m as shown in Fig. 2. As the result of the modification, a uniform distribution of the electric field was improved around ground electrode.
(a)

(b)

Fig. 1 Schematic view of the MCP-TOF

Fig. 2 (a) Previous ground electrode (b) Replaced
ground electrode and MCP-TOF

18

An experiment to evaluate a time resolution of the MCP-TOF was conducted at SB2 beam line in
HIMAC. The experimental set up is shown in Fig. 3. 84Kr beam (200 A MeV) was transported to the
MCP-TOF. In order to obtain the time resolution, a TOF between a trigger detector and the MCP-TOF was
measured. As the trigger detector, a 1-mm-thick plastic scintillator of which both ends were connected on
photomultiplier tubes was used. Two parallel plate avalanche counters (PPAC) were used to measure theposition distribution of the beam and to obtain the beam profile at the carbon foil by a ray-trace technique.
To measure total energy of the beam, an NaI(Tl) detector was set the downstream of the detectors. A typical TOF spectrum is shown in Fig. 4. In this measurement, the magnetic field was adjusted to 41.5 G so as
to the TOF spectrum was narrow. The time resolution is obtained by fitting the TOF spectrum with aGaussian function. The obtained width of the peak includes the intrinsic resolution of the trigger detector,
which is = 50 ps. By subtracting the contribution of the trigger detector, preliminary intrinsic time resolution was deduced as  ≈  175 ps.

Fig. 3 Experimental setup

Fig. 4 TOF spectrum. The red solid line is a fit of data points by a Gaussian.
References[1] Y. Yano, Nucl. Instr. and Meth. B 261 (2007) 1009.
[2] Y. Yamaguchi, et al., Nucl. Instr. and Meth. B 266 (2008) 4575.
[3] Y. Abe, et al., UTTAC Annual Report 2010, UTTAC-80 p. 19 (2011).
[4] J. D. Bowman, R. H. Heffner, Nucl. Instr. and Meth. 148 (1978) 503.

19

3.
MATERIALS AND CLUSTER SCIENCE

3.1

Zero Degree Electron Spectroscopy of 16 MeV C+
2 Ions

S. Tomita, S. Funada, Y. Shiina, K. Sasa, M. Sataka1 , M. Matsuda1 , M. Imai2 , K. Kawatsura3
The yields of secondary electron Ye induced by swift ions are well known to be almost proportional
to the electronic stopping power Se of incident charged partilcles, Ye = ΛSe , where Λ is called material
parameter. The relation holds wide range of materials over the four order of incident energy, not only for
protons but also for heavy atomic ions[1], except of some special cases. Strong suppression of secondary
electron yeild for molecular ion beam is one of example of the special case. The supression effect of
secondary electron per number of incident atom for 0.5 MeV/atom C+
4 is almost 50% of that of atomic ionwith same velocity[2]. Since the electronic stopping power of C+
4 is almost same as that of atomic ion[3],the supression mechanism should take place in the process of either transport of scattered electrons insidematerial or transmission of scattered electrons through material surface.
Recently, we have reported that the convoy electron yield per number of incident atom is almost
linear to the number of incident atom. These electrons can be considered to be mainly generated by thecapture of scattered electron to the continuum state of the projectile on the emergence from target surface.
Therefore, the result implies that the amount of scattered electron inside the target material with same
velocity as projectile atom should be almost linear to number of incident atoms. To shed a light on these
phenomena related to the transport of scattered electron inside target material, we have performed zero
degree electron spectroscopy with swift molecular ions.
The experiments were performed with ion beams provided by the tandem accelerator of the Japan
Atomic Energy Agency, Tokai. C+
2 ions were produced by ECR ion source from benzen gas. The ion
source was located on the high voltage terminal of the tandem accelerator. The ions were extracted bypotential difference of 10 kV and injected to the normal acceleration beam line by a 90◦ magnet. The mass
selected ions using a 180◦ magnet on the high voltage terminal, the ions were injected to the acceleration
tubes. The accelerated ions were mass selected again by 90◦ bending magnet and transported to theexperimental chamber.
The experimental apparatus used for the present experiment is described elsewhere in detail[4]. The
ions were injected on the target of thin carbon foil purchased from Arizona Carbon Foil Co. Inc.. The
nominal thickness was 3µg/cm2 . On the down stream of the target, 45◦ tandem parallel-plate spectrometer
was placed at zero degrees with respect to the direction of projectile ion beam. The resolution of thespectrometer is 3.2% without the deceleration of the electrons before entrance of second analyzer.
The obtained energy spectrum for 16 MeV C+
2 is shown in Fig.1. The prominent paek at 366 eVcorresponds to the convoy electrons which have same velocity as projectile ions. The other peak at 1.2
keV is the KLL Auger electrons from projectile ions. The energy corresponds that of C3+ ion reported
to be 230 eV in projectile frame[5]. In addition to the two peaks, thre is also two peaks of Coster-Kronigtransition, which can be found as a shoulder on the both energy side of the convoy peak. It is not possible
to determine the exact transition channel of the peak, due to poor energy resolution. But the position of1

Japan Atomic Energy Agency
Kyoto University
3
Kansai Gaidai University
2

21

peaks agree roughly with the value reported by Yamazaki[6] for C3+ +He collisions.
The electron yields of convoy electron, Coster-Kronig transition, and binary election for C+
2 are compared with that for C+ ion with same velocity and tabulated in Table1. Here we use the yield of KLL
Auger electrons for the normalization, because the strong cluster effect is not expected for does not the
inner shell electron excitation process. The cluster effect for the convoy electron yield is 4.3 which does
not agree with the linearity reported for 0.5 MeV/atom C+
n ions. We think that this value stems from bothcluster effect and loss electron, because of rather thin carbon foil thickness. The yield of Coster-Kronigtransition also shows cluster effect, which could stems also from thin target thickness, which will results
higher yield of low charge state for molecular beam.

Fig. 1. Energy spectrum of zero degree electrons induced by the irradiation of 16 MeV C+
2 ions through3 µg/cm2 carbon foil.

Table 1. Relative electron yield from 3µg/cm2 carbon foil. The yields are normarilzed with that of projectile KLL Auger electrons.

Y

≥

C+
2

¥

° ¢
/Y C+

Convoy electron
4.3

Coster-Kronig
2.3

Binary electon
0.8

References[1] H. Rothard, et. al., Phys. Rev. A 41, 2521 (1990).
[2] S. Tomita et. al., Phys. Rev. A 82, 044901 (2010)[3] S. Tomita et. al., Phys. Rev. A 73, 06901 (2006).
[4] K. Kawatsura et al., Nucl. Instr. and Meth. in Phys. Res. B 53, 421(1991).
[5] R. Bruch, et. al., Phys. Rev. A, 31, 310 (1985).
[6] Y. Yamazaki et. al., Phys. Rev. Lett. 57, 992(1986).

22

3.2

Coincidence measurement of secondary electrons with scattered ions
under irradiation of fast carbon-cluster ionsY. Shiina, R. Kinoshita, S. Tamura, K. Sasa, S. Ishii and S. Tomita
The swift atomic ion penetrate bulk material with losing its kinetic energy by producing scatteredelectrons, and inducing wake potential. As a result of the energy transfer, secondary particles ( electronsand sputtered atoms), and photons are produced and modification of the target materials might be caused
depending on the target and injected ions. If two or more atomic ions are injected simultaneously, thephysical process might be different from the case of atomic ion injection. Because the volume affected byatomic ion might have overlap, if the atomic distances between injected ions are close enough. This kindof physical process might take place when we inject fast cluster ions, such as Cn+. This is called cluster
effect, and have been observed in many cases such as the yield of secondary ions, sputtering yield,
stopping powers, equilibrium charge state, etc.
Among these phenomena, we investigated in the cluster effect of secondary electron yield. Because
swift ions mainly loses its kinetic energy through electronic stopping power, the behavior of secondary
electrons in the target material might be most important process to understand the cluster effects. We haveactually reported strong cluster effect on the secondary electron yield. Secondary electron yield per
number of incident atom for 0.5 MeV/atom C4+ ion is almost 50% of that of atomic ion with same velocity,while the electronic stopping power of C4+ is almost same as that of four atomic ions[3].
The mechanism of secondary electron emission can be understood as three step process. Scatteredelectrons are produced inside target material through scattering process by projectile ions (production).
The scattered electrons move inside material, and some of them are transported to the bulk surface(transport). A part of these electrons transmit from target surface overcoming ionization potential(transmission). Since the cluster effect on the stopping power is weak compared to that of secondary
electron yield. It seems that the secondary electron suppression mechanism should be attributed either tothe transport of scattered elections inside material or transmission process through the material surface,rather than the production process.
To investigate this problem further, we have studied the cluster effect of secondary electron, which
produced by close distant collisions. It is known that the secondary electron yield is higher for the close
distance collision. Therefore, we measured the correlation of secondary electron emission with the numberof scattered atoms in solids. The schematic setup is shown in figure 1. A SSD is located in forward angle.
The ions emitted in small angle (smaller than 3 degrees) are detected by SSD. The pulse height of SSD
signal is proportional to the number of atomic ion detected at the same time, thus, the number of scatteredatom can be determined. The secondary electron yield in backward angle is measured with MCP, incoincidence with the SSD signal.
Average of secondary electron yields as a function of the number of scattered atoms is shown in figure 2.
The more atoms were scattered the more secondary electrons were emitted. It should be noted that theincrease of secondary electron yields was almost linear to the number of scattered atoms. The linearity

23

implies that the increase is mainly attributed to the result of close distant collision. It is reported by Ogawa
et al. [4] for H+ ions that the wider the scattering angle was, the more secondary electrons were emitted.
We are planning to measure secondary electron yields by incident of atomic ions to compare with present
result. The comparison allows us to evaluate suppression effect of scattered elections from close distantcollisions. If the suppression effect is as same as that of secondary electrons, this might be one ofexperimental evidence that prove independence of the suppression mechanism from the production
process of scattered electrons.

Fig. 1. Schematic setup

Fig. 2. Average of secondary electron yields as a function of the number of scattered atoms
References[1] H. Rothard, K. Kroneberger, A. Clouvas, E. Veje, P. Lorenzen, N. Keller, J. Kemmler, W. Meckbach,and K. O. Groeneveld, Phys. Rev. A 41, 5 (1990).
[2] H. Arai, H. Kudo, S. Tomita, and S. Ishii, JPSJ. 78 (2009) 104301.
[3] S. Tomita, M. Murakami, N. Sakamoto, S. Ishii, K. Sasa, T. Kaneko, and H. Kudo, Phys Rev. A 82,
044901 (2010).
[4] H. Ogawa, H. Tsuchida and N. Sakamoto, Phys. Rev. A 68, 052901 (2003).

24

3.3

Detection of vacancy-type defects in InxGa1-xN alloys using amonoenergetic positron beam

T. Watanabe, A. Uedono, S. Ishibashi1, X. Q. Wang2, S. T. Liu2, G. Chen2, L. W. Sang3, M. Sumiya3, andB. Shen2
Introduction
Group III nitrides, along with their alloys, have been extensively studied because of their potential for
device applications such as light-emitting diodes, laser diodes, photo-detectors, and high electron mobility
transistors used in high-power and high-speed electronics. For InxGa1xN wurtzite alloys, cation sites are
randomly occupied by In or Ga atoms, where the difference between GaN and InN bond lengths is roughly
11%. Thus, the positions of atoms could fluctuate from the resulting stress, and this may lead to not only
compositional inhomogeneity but also to the introduction of dislocations and point defects. Because such
defects are known to closely relate to the optical and electrical properties of group-III nitrides, knowledgeof defect behaviors is crucial for the development of InxGa1xN-based devices. Positron annihilation is a
powerful technique for evaluating vacancy-type defects in semiconductors [1]. The studies of defects ingroup-III nitrides have been systematically performed, and the results show that positrons are a powerfulprobe for studying vacancies and vacancy complexes with impurities. In this report, we have usedmonoenergetic positron beams to probe native cation vacancies in InxGa1xN grown by plasma-assisted
MBE.
When a positron is implanted into condensed matter, it annihilates with an electron and emits two
511-keV  quanta [1]. The energy distribution of the annihilation  rays is broadened by the momentum
component of the annihilating electron-positron pair, which is parallel to the emitting direction of the 
rays. A freely diffusing positron may be localized in a vacancy-type defect because of Coulomb repulsion
from positively charged ion cores. Because the momentum distribution of the electrons in such defects
differs from that of electrons in the bulk material, these defects can be detected by measuring the Doppler
broadening spectra of the annihilation radiation. The resultant changes in the spectra are characterized by
the S parameter, which mainly reflects changes due to the annihilation of positron-electron pairs with alow-momentum distribution. In general, the characteristic value of S expected for the annihilation of
positrons due to their trapping by vacancy-type defects is larger than that for positrons annihilated fromthe free-state. For group-III nitrides, because an isolated nitride vacancy (VN) is positively charged, themajor trapping center of positrons is cation monovacancies such as In vacancy (VIn) and Ga vacancy (VGa)or their complexes such as VInVN and VGaVN.
Experiment
The samples investigated were200-600 nm thick InxGa1xN (0.05  x  0.90) grown on GaN/sapphire

1

Nanosystem Research Institute “RICS”,  National Institute of Advanced Industrial Science and Technology, Tsukuba, Japan
School of Physics, Peking University, China
3
Wide Bandgap Material Group, National Institute for Materials Science, Tsukuba, Japan225

templates using plasma-assisted MBE. The growth method and the optical properties of samples preparedby this method are described elsewhere [2]. The InN fractions were determined by using x-ray diffraction(XRD) reciprocal space mapping. Photoluminescence (PL) spectra were measured with a 325-nm He-Cd
laser as an excitation source and a Perkin-Elmer Lambda 950 UV-Vis-NIR spectrophotometer. All
measurements were made at room temperature. For comparison, MBE-grown InN (ne = 51017 cm3) was
also characterized. Details of the growth conditions and properties of InN are described elsewhere [3].
With a monoenergetic positron beam, the Doppler broadening spectra of the annihilation radiation were
measured with a Ge detector as a function of the incident positron energy E. Doppler broadening profiles
with 5  106 counts were then measured using a coincidence system. The low-momentum part wascharacterized by the S parameter, defined as the number of annihilation events over the energy range of
511 keV  E (where E = 0.76 keV) around the center of the peak.
Doppler broadening spectra corresponding to the annihilation of positrons in the delocalized (defect-free)state and the trapped by typical vacancies in ordered In0.5Ga0.5N were theoretically calculated using our
in-house QMAS (Quantum MAterials Simulator) code, which uses valence-electron wavefunctions
determined by the projector augmented-wave (PAW) method.
Results and Discussion
Figure 1 shows the S values of InxGa1xN (x =0.36, 0.44, and 0.90) grown using plasma-assisted MBE asa function of incident positron energy E. The SE curves for InN grown by plasma-assisted MBE and
GaN grown by hydride vapor phase epitaxy (HVPE) are also shown. For HVPE-GaN, the observed
increase in the S values at low E ( 0.1 keV) is associated with the annihilation of positrons at the surface,
and those above E = 20 keV correspond to the annihilation of positrons in the films, where the bulk S
value (E  20 keV) was close to that previously
reportedfor

defect-free

HVPE-GaN

[4].

For

InxGa1xN and InN, the decrease in the S value at highE (> 10 keV) can be attributed to the annihilation of
positrons in the GaN/sapphire template. For InxGa1xN(x =0.36, 0.44, and 0.90), the S value observed at E =3-7, 4-5 and 4-10 keV corresponds to the annihilationof positrons in the InxGa1xN film, respectively. For
InN, the S value tends to saturate at E = 10 ~ 15 keV,suggesting the annihilation of positrons in the InN
film. For this sample, the S values at E  20 keV werehigher than the saturated S value, suggesting theannihilation of positrons by vacancy-type defects near
the InN/GaN interface. Similar behavior of the S
values was also observed for InxGa1xN, and this is
typicalforgroup-IIInitride

films

grown

by

heteroepitaxial growth [4].

26Fig.1. S parameters as a function of incident
positron energy E for InxGa1-xN (x = 0.36,
0.44, and 0.90), InN, and GaN.

Figure 2 shows (a) the FWHM (full-width at half
maximum) values of XRD -rocking curves for(002) and (102), (b) the line-width (FWHM) of PLlines [2], and (c) the S values for InxGa1xN as afunction of In composition x. It can be seen that the
FWHMs for both (002) and (102) tend to increase
with increasing x, suggesting a decrease in the crystal
quality for In-rich InxGa1xN. The line-width of the
PL peaks also broadened with increasing x, andreached the maximum at the mid-In composition.
The observed increase in the FWHM values of XRD
and PL intensity can be associated with the alloy
disorder or compositional inhomogeneity caused by
the increase in the strain energy [2].
Moredetails

and

other

resultsofthesemeasurements are described elsewhere [5].
Summary
We studied vacancy-type defects in InxGa1xN
grown

by

plasma-assisted

MBE

using

a

monoenergetic positron beam. Doppler broadening
spectra were measured as a function of the incident
energy of positrons for 200-600 nm thick InxGa1xN
grown on GaN/sapphire templates. Coincidence
Doppler broadening spectra were also measured, andthose were compared with the results calculatedusing the PAW method. The concentration of

Fig.2. (a) FWHM values of XRD -rocking
curves for (002) and (102), (b) FWHM values of
PL peak [2] and (c) S values of InxGa1xN as afunction of the In molar fraction x. In (c), thecalculated Sx relationship (solid curve marked
as Cal.) for defect-free InxGa1xN and the shifted
one (broken curve) are also shown.

vacancy-type defects increased with increasing In composition x, and reached the maximum at x = 0.44 ~0.56. A clear correlation between the line-width of PL and the concentration of vacancy-type defects was
obtained.
References[1] R. Krause-Rehberg et al., Positron Annihilation in Semiconductors, Solid-State Sciences(Springer-Verlag, Berlin, 1999) vol. 127.
[2] S. T. Liu et al., J. Appl. Phys. 110, 113514 (2011).
[3] X. Q. Wang et al., Appl. Phys. Express. 5, 015502 (2012).
[4] A. Uedono et al., J. Appl. Phys. 103, 104505 (2008).
[5] A. Uedono et al., J. Appl. Phys. 112, 014507 (2012)

27

3.4

Site population of Fe ions in Mg-containing Fe3O4 nanoparticles
determined by Mössbauer spectroscopy

D. Isaka, M. Kishimoto, H. Yanagihara, E. Kita
Magnetic nanoparticles have attracted much attention because of their potential to generate heat inmagnetic hyperthermia and thermoablation for cancer therapy. We have studied ferromagnetic
nanoparticles, especially cobalt-doped magnetite particles, as high heat-generating materials for magnetic
hyperthermia and thermoablation [1]. In addition to the high heating ability, the biocompatibility ofmagnetic materials must be considered for their practical use. The biocompatibility of elements other thaniron, cobalt in particular, needs to be carefully checked, even when they are used as dopants. Therefore,
we have synthesized Mg-containing iron oxide particles and reported their magnetic properties[2] because
Mg is believed to be a safe element. To obtain high heating ability, the magnetic properties ofnanomagnets need to be controlled precisely. For spinel ferrites, the site population of divalent elements,
Mg in the present case, determines the magnetic properties. In the present study, the site preference of Fe
ions on the spinel structure, which is closely connected to their influence on the magnetic properties, wasinvestigated with a Mössbauer study.
Spinel-structured Mg-containing iron oxide nanoparticles, (Mg)Fe3O4, were synthesized bycoprecipitation and a hydrothermal process. We have labeled the various nanoparticle samples MTH0
(pure Fe3O4) through MTH6, corresponding to the increasing Mg content from 0 to 10.0 at% with respect
to the total Fe content: the 10 at% concentration corresponds to Mg0.33Fe2.67O4. The magnetization of dry
powdered samples was measured using a vibration sample magnetometer (VSM). The particle size andcrystal structure were obtained using X-ray diffraction (XRD). Mössbauer spectra were recorded at 77 K
and were numerically analyzed using commercially available fitting software, MössWinn 4.0.
The basic characteristics of the (Mg)Fe3O4 particles in the various samples are summarized in Table
I. The magnitude of the coercive forces peaked for the MTH1 sample and then decreased with increasing
Mg content.
Table I. Characteristics of (Mg)Fe3O4 particles.
Mg content DXRD
Hc
Ms
Sampleat%(nm)(Oe) (emu/g)

Figure 1 shows the Mössbauer spectraof (Mg)Fe3O4 particles recorded at 77 K. The
solid lines indicate the fitted results. For all

MTH0

0

41

141

85

samples, the spectra were composed of three

MTH1

2.0

33

155

77

ferromagnetic subspectra, which correspond

MTH2

3.2

24

136

70

MTH3

4.0

21

109

68

MTH4

6.0

18

71

63

MTH5

8.0

15

41

54

octahedral sites (B sites), and that with the

MTH6

10.0

14

40

51

second largest hyperfine field (Hhp), 507 kOe,

to those from Fe3O4. The fitted results are
summarized in Table II. The subspectrumwith the highest hyperfine field (Hhp), about
515 kOe, is attributed to the Fe3+ ions into tetrahedral sites (A sites). The smallest one,28

470-480 kOe, corresponds to the Fe2+ ions in the octahedral sites (B sites). Compared with room
temperature spectra, the subspectra from Fe2.5+ ions disappeared due to the electronic charge order, namely,
Verwey transition, and traces of the superparamagnetism were not detected at 77 K, suggesting thatsuperparamagnetic parts were ordered magnetically at this temperature. The populations of Fe2+ and Fe3+on the B sites in the spectrum for MTH0 without Mg is not identical to those of bulk and slightly different.
The distribution can be estimated from the area ratios of the subspectra summarized in Table II. To
determine the occupation, Mössbauer analyses were generally performed at 77 K. Mg atoms tend tooccupy B sites in the thin Mg concentration region below Mg0.5Fe2.5O4 [3]. The concentration of Mg atoms
in this study is thinner than that found inprevious research. As seen in Table 1, therelative ratio of Fe2+ ions tends todecrease with increasing Mg content.
This is reasonably explained by theincrease in the occupation of Mg ions at
B sites in this concentration range.
Table II. Mössbauer fitting parameters
Data were recorded at 77 K. 3A, 3B, and 2B sites
correspond to Fe3+ ions at A sites, Fe3+ ions at B sites,
and Fe2+ ions at B sites, respectively.
Sample

ion
3A
3B
2B

Hhf
(kOe)
513
519
492

IS
(mm/s)
0.359
0.621
0.856

QS
(mm/s)-0.022-0.043-0.481

P
(%)
33.0
23.1
41.8

MTH0

MTH1

3A
3B
2B

512
517
477

0.342
0.626
0.863

-0.0370.030-0.090

41.1
32.0
24.8

MTH2

3A
3B
2B

507
509
474

0.353
0.642
0.846

-0.013-0.013-0.088

34.4
34.4
29.0

MTH3

3A
3B
2B

507
508
470

0.355
0.674
0.853

-0.010-0.021-0.093

37.9
35.7
23.7

MTH4

3A
3B
2B

505
508
468

0.360
0.650
0.836

-0.0180.025-0.061

38.5
39.8
21.7

References[1] E. Kita et al., J. Phys. D: Appl. Phys. 43 (2010) 474011.
[2] D. Isaka, M. Kishimoto, H. Yanagihara, and E. Kita, UTTAC ANNUAL REPORT 2011 (2012) 20.
[3] F. Nakagomi et al., J. Solid State Chem. 182 (2009) 2423.

29

3.5

Development of E-E telescope ERDA detector

I. Harayama, K. Nagashima, Y. Hirose1, H. Oikawa, R. Akiyama, S. Kuroda, H. Matsuzaki2,
D. Sekiba
Recently the materials designs including light elements are intensively suggested in the various fields,such as lithium (Li), carbon (C), nitrogen (N), oxygen (O) and fluorine (F). In particular, the N- or
F-doped metal oxides have been well studied from the viewpoint of the solar-cell and battery, etc. In thecase of synthesizing new materials, it is generally important to determine the accurate concentration ofeach element. However the estimation of the concentration is not straightforward, when the materials
contain several light elements. In this case, elastic recoil detection analysis (ERDA) using heavy ions iseffective. Especially, the E-E telescope ERDA using ionization chamber and/or time-of-flight (TOF)
ERDA are better tools for the particle identification. Here we present our recent development of the E-E
telescope ERDA detector, which can be constructed without expensive parts [].
We adopted the simple combination of the ionizationchamber and the Si surface detector (SSD) as schematicallyshown in Fig. 1. In the concept of the design of the ionizationchamber, we focused our chief attention onto the identificationof O and N recoiled by 40 MeV chlorine ion (35Cl7+). The PRgas (90% Ar + 10% CH4) is adopted for the ionization chamber,and the pressure of the PR gas is fixed at 6000 Pa. From someliteratures, we estimate the energy resolution of the ionizationchamber as in principle about ~ 100 keV. Therefore, thedifference of the energy loss E of O and N in the ionizationchamber should be 400 ~ 500 keV to identify them. By meansof the SRIM calculation [2], we set the length of the ionizationchamber along the beam direction as 50 mm. The electric
potentials of the cathode, Frisch grid and the anode are set at 0
V, 30 V and 180 V, respectively. These values are referred from Figure 1. The schematic drawings of thethe literature of accelerator mass spectroscopy (AMS). All the
setup is compactly mounted on the single ICF152 flange, andionization chamber: a top view of the gaschamber (a) and a cutaway view seen froma front of the ionization chamber (b).

the gas chamber is separated from the vacuum chamber by the mylar film with 3.5 m thickness.
Figure 2 (a) ~ (d) display the two-dimensional maps (2D map) of E and Eres taken on (a)CoON/MgAl2O4, (b) LiTaO3 (bulk sample), (c) InOF/ZrO2 and (d) SiO2/Si by using the developed E-E
telescope detector. The recoil angle is 30 degree from the beam direction. Here, Eres is the energy of1
2

Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku Tokyo 113-0033, Japan
School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku Tokyo 113-8656, Japan

30

particle measured on SSD, and E + Eres = Etotal. We can see that the various light elements Li, C, N, O andF are well distinguished on the maps. Some light metals, such as Al and Mg are separately observed besidethe intense signals of forward scattered Cl ions. Finally, we also put another SSD to detect thebackscattered particles in the direction of 150 degree from the beam direction, so that we can determine
the whole elemental concentration of materials, which include the both heavy metals and light elements.

Figure 2. The E-Eres two dimensional maps taken on (a) CoON/MgAl2O4, (b) LiTaO3 (bulk sample), (c) InOF/ZrO2 and (d)SiO2/Si. Here, Eres stands for the energy measured by SSD. E + Eres is equal to Etotal of the recoiled or forward scattered particles.

References[1] J.P.Stoquert, G. Guillaume, M. Hage-ali, J.J. Grob, C. Ganter and P. Siffert. Nucl. Instr. and Meth.
B44(1989)184-194.
[2] SRIM2013, http://www.srim.org.

31

4.
ACCELERATOR MASS SPECTROMETRY

4.1

Distribution of iodine 129 from the Fukushima No. 1 nuclear power
plant accident

K. Sasa, K. Sueki, T. Takahashi, M. Matsumura, Y. Satou, S. Abe, N. Kinoshita1 and H. Matsuzaki2
A tremendous amount of radioactivity was discharged due to the damage to cooling systems of
nuclear reactors in the Fukushima No.1 nuclear power plant in March 2011. Fukushima and its adjacentprefectures were contaminated with fission products from the accident. We measured short-lived
radionuclides such as 129mTe, 131I, 134Cs, 136Cs and 137Cs in the surface soils immediately after the accident
at Fukushima and the Kanto area [1]. Figure 1 shows geographical distributions of radioactive iodine,tellurium, and cesium in surface soils of central-east Japan as determined by gamma ray spectrometry.

Iodine-131

Tellurium-129m

kBq m-2

Cesium-137

kBq m-2

kBq m-2

102

103

10

102

1

1

103
2

10

10

Figure 1. Geographical distribution of 131I, 129mTe and 137Cs on 29 March, 2011 [1].
Radioactive iodine is one of the most important radionuclides released from the Fukushima No.
1 nuclear power plant accident. 131I has a short half-life time of about 8 days. Because of the difficulty ofmeasuring 131I at this time, it is expected to estimate 131I precipitation from 129I with a long half-life time of
1.57  107 years. We have measured 129I concentrations in surface soils that we already got results of 131I
concentrations. 129I/127I ratios were measured by accelerator mass spectrometry (AMS) at MALT, The
University of Tokyo [2]. Stable iodine of 127I was determined by inductively coupled plasma mass
spectrometry (ICP-MS). We got a result that the average 129I concentration was about 0.41 mBq/kg prior
to the Fukushima No. 1 nuclear power plant accident as 129I background at the eastern area of Fukushima
Prefecture. After the accident, average isotopic ratio of 129I/131I is estimated to 26.0 ± 5.6 as at 11 March
2011. 129I and 131I has a good linear correlation, it is therefore possible to reconstruct 131I distribution from129

I analysis in the future. Figure 2 shows the distribution of 129I precipitation from the Fukushima No. 1

nuclear power plant accident at the eastern area of Fukushima Prefecture.

1
2

Shimizu Co.
MALT, The University of Tokyo

33

129I [Bq/m2]

Figure 2. Distribution of 129I precipitation from the Fukushima No. 1 nuclear power plant accident
at the eastern area of Fukushima Prefecture as of March 2011.
Acknowledgements
This work was supported by JSPS KAKENHI Grant Numbers 24246156 and 24110006, andReconstruction support program for eastern Japan at the University of Tsukuba.
References[1] Norikazu Kinoshita, Keisuke Sueki, Kimikazu Sasa et al., PNAS, 108 (2011) 19526-19529.
[2] Hiroyuki Matsuzaki et al., Nucl. Instr. Meth. Phys. Res. B 259, (2007) 721-726.

34

5.
INTERDISCIPLINARY RESEARCH

5.1

Comparison of calibration curves for a new and old Si (Li) detectors
with different energy resolution

M. Kurosawa, K. Sasa and S. Ishii
Introduction
Reliable calibration factors or sensitivities of Si(Li) X-ray detector (expressed in counts/g/cm2/C or
cts/g/g/C) are important for PIXE quantification. The factors, including solid angle and detection
efficiency of the detector, have been usually determined based on measurements of X-ray yields fromthin-film or solid reference materials with known compositions [1-7]. The thin-film reference materials
are fragile, sometimes impure, and the thicknesses are uncertain by 510% [2]. Thus, the solidreference materials are advantageous in case that suitable correction for energy loss of incident beams
and self-absorption of generated X-rays in matrix are performed for the X-ray yields [2]. In this report,
we have determined the sensitivities by using solid reference materials to compare the analyticalcapability of a newly equipped Si(Li) X-ray detector with higher energy resolution and that of old
detector with lower energy resolution in the PIXE facility installed on 1-MV Tandetron accelerator at
the Tandem Accelerator Complex, University of Tsukuba.
Reference materials
The detector sensitivities for each element wereTable 1.

Reference materials

determined by using three multielement reference

Sampleglass materials (NIST SRM 1412 and 1873), two

SRM 1412
SRM 1873 K-489
SRM 1873 K-963
KTiOPO4
ApatiteCr2O3NiO
SrTiO3Y3 Al5O12
Zircon
LiNbO3AgGaS 2InP
LaAlO3
Gd 3Ga5O12
LiTaO3
CdWO4
PbMoO4mineral reference materials, and thirteen synthetic
crystals for semiconductor and optical devices(Table 1). Elemental contents in the referencematerials were selected from the certified values forthe reference glass materials and the mineralreferences, and those in the synthetic crystals wereadopted from the stoichiometric compositions.
Pieces of each material, about 3 mm  3 mm  2 mm,
were mounted on a glass slide with resin and thenwere cut and polished. The specimens were coatedwith a carbon film to prevent electrostatic charging
and to measure the integrated charges.
Experimental
PIXE analyses were performed at the 1MV
Tandetron. A 1.92-MeV proton beam was focused toa 33 x 33 m spot on the specimens. The beam

35

Composition*referen ce glass material*referen ce glass material*referen ce glass material*
synthetic crystal
natural mineral refe rence*synthetic crystal
synthetic crystal
synthetic crystal
synthetic crystal
natural mineral refe rence*synthetic crystal
synthetic crystal
synthetic crystal
synthetic crystal
synthetic crystal
synthetic crystal
synthetic crystal
synthetic crystal

Maker#
NIST
NIST
NIST
POE
MAC
NCL
NCL
POE
POE
MAC
UO
POE
POE
NCL
ELAN
NCL
MT
POE

*Composition: SRM1412: mixed glass of Li, B, Na, Si,
Mg, K, Ca, Zn, Sr, Cd, Ba, and Pb oxides; K-489: Ba-Zn
silicate glass with minor Ti, Fe, Zr, Ba, Ce, Ta, and Pb;
K-963: Ba-Zn silicate glass with minor P, Cr, Ti, Ni, Ge,
Zr, Ba, Eu, Th, and U; Apatite: Ca5(PO4)3(F,Cl,OH);
Zircon: (Zr,Hf)SiO 4.
#NIST: National Institute of Standards and Technology,
U.S.A; POE: Phiscience Opto-electronics CO., Ltd.,
Beijing, China; MAC: Micro-Analysis Consultants Ltd.,
Cambridgeshire, U.K; NCL: Nakazumi Crystal Laboratory, Osaka, Japan; UO: Unioriental Optics Co., Ltd.,
Beijing, China; ELAN: ELAN Ltd., Saint-Petersburg,
Russia; MT: MolTech GmbH, Berlin, Germany.

incidence was normal to the specimen surface, and the X-ray
measurement take-off   angle   was   45˚.   The characteristic X-rays
were simultaneously collected by the new and old Si(Li)
X-ray-energy detectors (Fig. 1). The new detector (Sirius 30+
detector, e2V Scientific Instruments, UK) had the area of thedetector of 30 mm2, and the energy resolution was 137 eV at 5.9
keV. The old detector (Sirius detector, Gresham Scientific
Instruments, UK) had the area was 50 mm2, and the resolution
was 155 eV at 5.9 keV. The energy resolutions were determinedby measurements of Mn impurities in a mineral willemite. The
sample-to-detector distances were 2.5 cm for both detector, anda 55-m-thick Mylar filter was placed between the specimen
and both detector. The X-ray spectra were recorded by amultichannel analyzer. The beam current was set at 0.05–0.25
nA to obtain good counting statistics. The total charge wasdetermined by integrating the target currents, and all specimens
were analyzed at integrated charges of 0.03 to 0.71 C. A
suppressor electrode was placed near the sample surface toFig.1. Schematic drawing of thesample chamber in the PIXE
facility. The incident proton beamand the detector angles are at 90°
and 135°, respectively, to thespecimen surface.

prevent loss of integrated charge by secondary electron emission from insulating matrices. The detector
sensitivities were calculated based on the method by Kurosawa et al [8]. In the calculations, L X-ray
production cross sections for Sr, Y, Zr, Nb, and Mo were estimated from interpolations for data of Orlicet al [9] and Reis and Jesus [10].
Results and Discussion
At the PIXE measurements, we observed K X-ray
peaks from Si, P, S, Cl, K, Ca, Ti, Cr, Fe, Ni, Zn,
Ga, Ge, Sr, Y, Zr, Nb, and Mo, and for L X-ray
peaks from Sr, Y, Ze, Nb, Ag, Cd, In, Ba, La, Ce,
Eu, Gd, Hf, Ta, W, Pb, Th, and U. Since the newdetector had the higher energy resolution, it waspossible to detect easily shoulder peaks of elementof interest in the complex spectra generated by
duplication of X-ray peaks from various elements(Fig. 2). In the spectrum of NIST SRM-1412 glassby the new detector, escape peaks of Cd and K on
intense peak of Si, and a shoulder peak of Cd on
intense peak of K were easily distinguished. A
weak peak of trace Fe was also well shaped,
indicating that the new detector is possible to36

Fig.2. PIXE spectra of NIST SRM-1412
glass by the old detector (upper) and the
new detector (lower). esc: escape peaks.

Fig.3. Detector sensitivities for K and L X-rays (1.92-MeV proton beam, 55 m-thick mylar filter)of the new detector (a) and the old detector (b). The sensitivities were calculated from PIXE
measurements of three reference glass materials (open squares) and fifteen synthetic and natural
crystals (open circles). Small dots represent the curves fit to the reference-glass and crystal data.
analyze trace elements at the measurements of relatively lower intensities. Based on the measured
intensities, we determined the sensitivities for the both detectors (Fig. 3). The most of elements were
contained in more than one kind of specimens, so the sensitivities for each element were determined byan average of the values from the several specimens. The values from the different specimens were
within a 3% relative difference, indicating the appropriate corrections for difference of matrices. The
sensitivities of the both detectors at each element were almost identical in spite of the smaller detectorarea of the new detector (Fig. 3). Although a Si(Li) detector with smaller active area should represent
basically lower sensitivities as shown in Watjen and Cave [5], the both detectors demonstrated thenearly same capabilities of X-ray detection. Thus, sensitive PIXE analyses with high energy-resolution
can be expected by using the new detector.
References[1] W. Maenhaut and H. Raemdonck, Nucl. Instr. Meth., B1 (1984), 123.
[2] J. L. Campbell et al., Nucl. Instr. Meth., B44 (1990), 347.
[3] M. Budnar et al., Nucl. Instr. Meth., B49 (1990), 138.
[4] I. Orlic et al., Nucl. Instr. Meth., B49 (1990), 166.
[5] U. Watjen and H. Cave, Nucl. Instr. Meth., B109/110 (1996), 395.
[6] S. Gama et al., Nucl. Instr. Meth., B181 (2001), 150.
[7] D. Cohen et al., Nucl. Instr. Meth., B189 (2002), 81.
[8] M. Kurosawa et al., Nucl. Instr. Meth., B266 (2008), 3633.
[9] I. Orlic et al., At. Data Nucl. Data Table, 56 (1994), 159.
[10] M. A. Reis and A. P. Jesus, At. Data Nucl. Data Table, 63 (1996), 1.

37

6.

LIST OF PUBLICATIONS

The publications listed here are those released in the fiscal year 2012 by all the workers listed on p.52.

6.1 Journals
ACCELERATOR AND EXPERIMENTAL FACILITIES
1.

A. Ozawa, T. Uesaka and M. Wakasugi, the Rare-RI Ring Collaboration, The rare-RI ring, Prog.
Theor. Exp. Phys., 03C009 (2012).

2.

Kimikazu Sasa, Damage Situation by the Great East Japan Earthquake and Post-quake
Reconstruction Project of the Tandem Accelerator Facility at the University of Tsukuba, J. Particle
Accelerator Society of Japan, Vol.9, No.1, 14-21 (2012).

NUCLEAR PHYSICS
3.

K. Morita, K. Morimoto, D. Kaji, H. Haba, K. Ozeki, Y. Kudou, T. Sumita, Y. Wakabayashi, A.
Yoneda, K. Tanaka, S. Yamaki, R. Sakai, T. Akiyama, S. Goto, H. Hasebe, M. Huang, T. Huang, E.
Ideguchi, Y. Kasamatsu, K. Katori, Y. Kariya, H. Kikunaga, H. Koura, H. Kudo, A. Mashiko, K.
Mayama, S. Mitsuoka, T. Moriya, M. Murakami, H. Murayama, S. Namai, A. Ozawa, N. Sato, K.
Sueki, M. Takeyama, F. Tokanai, T. Yamaguchi, and A. Yoshida, New Result in the Production and
Decay of an Isotope, 278113, of the 113th Element, J. Phys. Soc. Jpn., Vol.81, 103201 (2012).

4.

D. Kameda, T. Kubo, T. Ohnishi, K. Kusaka, A. Yoshida, K. Yoshida, M. Ohtake, N. Fukuda, H.
Takeda, 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,
Y. Mizoi, M. Matsushita, K. Ieki, N. Kobayashi, K. Tanaka, Y. Kawada, N. Tanaka, S. Deguchi, Y.
Satou, Y. Kondo, T. Nakamura, K. Yoshinaga, C. Ishii, H. Yoshii, Y. Miyashita, N. Uematsu, Y.
Shiraki, T. Sumikama, J. Chiba, E. Ideguchi, A. Saito, T. Yamaguchi, I. Hachiuma, T. Suzuki, T.
Moriguchi, A. Ozawa, T. Ohtsubo, M. A. Famiano, H. Geissel, A. S. Nettleton, O. B. Tarasov, D.
Bazin, B. M. Sherrill, S. L. Manikonda, and J. A. Nolen, Observation of new microsecond isomers
among fission products from in-flight fission of 345 MeV/nucleon 238U, Phys. Rev. C 86, 054319(2012).

5.

S. Naimia, S. Nakamura, Y. Ito, H. Mita, K. Okada, A. Ozawa, P. Schury, T. Sonoda, A. Takamine, M.
Wada, H. Wollnik, An rf-carpet electrospray ion source to provide isobaric mass calibrants fortrans-uranium elements, Int. J. Mass Spectrom., 337, 24–28 (2013).

39

6.

H. Ueno, H. Miyatake, Y. Yamamoto, S. Tanimoto, T. Shimoda, N. Aoi, K. Asahi, E. Ideguchi, M.
Ishihara, H. Izumi, T. Kishida, T. Kubo, S. Mitsuoka, Y. Mizoi, M. Notani, H. Ogawa, A. Ozawa, M.
Sasaki, T. Shirakura, N. Takahashi, and K. Yoneda,  β-delayed neutron and γ-ray spectroscopy of 17C
utilizing spin-polarized 17B, Phy. Rev. C 87, 034316 (2013).

7.

Y. Ishibashi, D. Nagae, Y. Abe, T. Nagatomo, A. Ozawa, H. Suzuki, S. Fukuoka, R. Nishikiori, T.
Niwa, K. Matsuta, Y. Tagishi, Production of nuclear polarization for unstable nucelai via polarizationtransfer reaction, Hyperfine Interaction , Proceedings of the 4th Joint International Conference onHyperfine Interactions and International Symposium on Nuclear Quadrupole Interactions (HFI/NQI2012),Beijing, China, 10–14 September 2012,
http://rd.springer.com/article/10.1007/s10751-012-0750-0

8.

T. Shizuma, T. Hayakawa, H. Ohgaki, H. Toyokawa, T. Komatsubara, N. Kikuzawa, T. Inakura, M.
Honma, H. Nakada, Dipole strength distribution in 56Fe, Phys. Rev. C 87, 024301 (2013).

9.

B. Ding, Y. H. Zhang, X. H. Zhou, G. X. Dong, F. R. Xu, M. L. Liu, G. S. Li, N. T. Zhang, H. X.
Wang, H. B. Zhou, Y. J. Ma, Y. Sasakiz, K. Yamada, H. Ohshima, S. Yokose, M. Ishizuka, T.
Komatsubara, K. Furuno, High-spin states in 127I, Phys. Rev. C 85, 044306 (2012).

10. B. Ding, H. X. Wang, H. Jiang, Y. H. Zhang, X. H. Zhou, Y. M. Zhao, S. T. Wang, M. L. Liu, G. S. Li,
Y. Zheng, N. T. Zhang, H. B. Zhou, Y. J. Ma, Y. Sasaki, K. Yamada, H. Ohshima, S. Yokose, M.
Ishizuka, T. Komatsubara, K. Furuno, High-spin level scheme of doubly odd 128I, Phys. Rev. C 86,
034302 (2012).
11. S. Kubono, N. B. Dam, S. Hayakawa, H. Hashimoto, D. Kahl, H. Yamaguchi, Y. Wakabayashi, T.
Teranishi, N. Iwasa, T. Komatsubara, S. Kato, A. Chen, S. Cherubini, S. H. Choi, I. S. Hahn, J. J. He,
H. K. Le, C. S. Lee, Y. K. Kwon, S. Wanajo, H.-T. Janka, Alpha-Cluster  Dominance  in  the  αp  Process  in Explosive Hydrogen Burning, Prog. Theor. Phys. (Kyoto), Suppl. 196, 346 (2012).
12. J. J. He, L. Y. Zhang, A. Parikh, S. W. Xu, H. Yamaguchi, D. Kahl, S. Kubono, J. Hu, P. Ma, S. Z.
Chen, Y. Wakabayashi, B.H. Sun, H.W. Wang, W. D. Tian, R. F. Chen, B. Guo, T. Hashimoto, Y.
Togano, S. Hayakawa, T. Teranishi, N. Iwasa, T. Yamada, T. Komatsubara, Key 18Ne(α, p) 21Na
breakout reaction in x-ray bursts: first experimental determination of spin-parities for α resonances in22

Mg , via resonant elastic scattering of 21Na + p, arXiv:1301.4283, (2013).

13. K. Setoodehnia, A. A. Chen, D. Kahl, T. Komatsubara, J.José, R. Longland, Y. Abe, D. N. Binh, J.
Chen, S. Cherubini, J. A. Clark, C. M. Deibel, S. Fukuoka, T. Hashimoto, T. Hayakawa, J. Hendriks,
Y. Ishibashi, Y. Ito, S. Kubono, W. N. Lennard, T. Moriguchi, D. Nagae, R. Nishikiori, T. Niwa, A.
Ozawa, P. D. Parker, D. Seiler, T. Shizuma, H. Suzuki, C. Wrede, H. Yamaguchi, T. Yuasa, Nuclear

40

structure of 30S and its implications for nucleosynthesis in classical novae, arXiv:1210.1194, (2012)ACCELERATOR MASS SPECTROMETRY
14. Dong Kejun, Li Shizhuo, He Ming, Kimikazu Sasa, Yuki Matsushi, Huang Baojian, Ruan Xiangdong,
Guan Yongjing, Tsutomu Takahashi, Keisuke Sueki, Li Chaoli, Wu Shaoyong, Wang Xianggao, Shen
Hongtao, Yasuo Nagashima, Jiang Shan, Methodological study on exposure date of Tiankeng by
AMS measurement of in situ produced cosmogenic 36Cl, N. I. M. Phys. Res. B 294, 611–615 (2013).
MATERIALS AND CLUSTER SCIENCE
15. K. Ozeki, D. Sekiba, T. Suzuki, K. Kanda, M. Niibe, K.K. Hirakuri, T. Masuzawa, Influence of thesource gas ratio on the hydrogen and deuterium content of a-C:H and a-C:D films: Plasma-enhanced
CVD with CH4/H2, CH4/D2, CD4/H2 and CD4/D2, Applied Surface Science 265, 750-757 (2013).
16. D. Sekiba, N. Takemoto, M. Okada, S. Ishii, T. Sakurai, K. Akimoto, Hydrogen isotope tracer
experiment in a-C:H film deposition: Reactive RF magnetron sputtering with CH4 and D2, Diamond& Related Materials 27-28, 60-63 (2012).
17. H. Tsuchida, S. Tomita, K. Nishimura, R. Murakoshi, M. Naitoh, K. Sasa, S. Ishii, A. Yogo and A.
Itoh, Properties of fast carbon cluster micro beams produced with a tapered capillary, Nucl. Instrum.
Methods Phys. Res. B 293, 6-10 (2012).
18. L. Kong, A. Uedono, S. V. Smith, Y. Yamashita, and I. Chironi, Synthesis of silica nanoparticles using
oil-in-water emulsion and the porosity analysis, J. Sol.-Gel Sci. Technol. 64, 309-314 (2012).
19. A. Uedono, T. Moriya, T. Tsutsui, S. Kimura, N. Oshima, R. Suzuki, S. Ishibashi, H. Matsui, M.
Narushima, Y. Ishikawa, M. Graf, and K. Yamashita, Vacancy-type defects introduced by gas cluster
ion-implantation on Si studied by monoenergetic positron beams, Jpn. J. Appl. Phys. 51, 111801(1-5)(2012).
20. A. Uedono, S. Ishibashi, T. Watanabe, X. Q. Wang, S. T. Liu, G. Chen, L. W. Sang, M. Sumiya, and B.
Shen, Vacancy-type defects in InxGa1–xN alloys probed using a monoenergetic positron beam, J.
Appl. Phys. 112, 104507(1-5) (2012).
21. W. Zhou, Z. Chen, N. Oshima, K. Ito, B. E. O’Rourke, R. Kuroda, R. Suzuki, H. Yanagishita, T.
Tsutsui, A. Uedono, and N. Hayashizaki, In-situ characterization of free-volume holes in polymer thinfilms under controlled humidity conditions with an atmospheric positron probe microanalyzer, Appl.
Phys. Lett. 101, 104102(1-3) (2012).

41

22. A. E. Hughes, S. Mayo, Y. S. Yang, T. Markley, S. V. Smith, S. Sellaiyan, A. Uedono, S. G. Hardina,and T. H. Mustera, Using X-ray tomography, PALS and Raman spectroscopy for characterization of
inhibitors in epoxy coatings, Progress in Organic Coatings 74, 726-733 (2012).
23. A. Uedono, S. Ishibashi, K. Tenjinbayashi, T. Tsutsui, K. Nakahara, D. Takamizu, and S. F. Chichibu,
Defect characterization in Mg-doped GaN studied using a monoenergetic positron beam, J. Appl.
Phys. 111, 014508(1-6) (2012).
24. A. Uedono, Y. Yamashita, T. Tsutsui, Y. Dordi, S. Li, N. Oshima, and R. Suzuki, Vacancy clusteringand its dissociation process in electroless deposited copper films studied by monoenergetic positron
beams, J. Appl. Phys. 111, 104506(1-5) (2012).
25. S. F. Chichibu, K. Hazu, Y. Ishikawa, M. Tashiro, H. Namita, S. Nagao, K. Fujito, and A. Uedono,Time-resolved photoluminescence, positron annihilation, and Al0.23Ga0.77N/GaN heterostructure
growth studies on low defect density polar and nonpolar freestanding GaN substrates grown by
hydride vapor phase epitaxy, J. Appl. Phys. 111, 103518(1-11) (2012).
26. A. Uedono, K. Tenjinbayashi, T. Tsutsui, Y. Shimahara, H. Miyake, K. Hiramatsu, N. Oshima, R.
Suzuki, and S. Ishibashi, Native cation vacancies in Si-doped AlGaN studied by monoenergetic
positron beams, J. Appl. Phys. 111, 013512(1-5) (2012).
27. M. Sometani, R. Hasunuma, M. Ogino, H. Kuribayashi, Y. Sugahara, A. Uedono, and K. Yamabe,
Variation of chemical vapor deposited SiO2 density due to generation and shrinkage of open space
during thermal annealing, Jpn. J. Appl. Phys. 51, 021101(1-3) (2012).
28. T. Kawasaki, M. Takahashi, T Ohhara, I. Tanaka, K. Kusaka, T. Hosoya, T. Yamada and K. Kurihara,
Structure of Morpholinium Tribromoplumbate C4H8ONH2PbBr3 studied by the single-crystal
neutron diffraction, J. Phys. Soc. Jpn., 81, 094602-1 – 6 (2012).
29. E. Kita, H. Yanagihara, K. Mibu, T. Niizeki, J. Inoue, Development of Functional Magnetic Materials
Free of Platinum Group Elements with Controlled Interfaces, Magnetics Jpn., 7, 308-313 (2012)42

6.2 International conferences
1.

Akira Ozawa, Nuclear mass measurements for the r-process in Rare-RI Ring, 1st Visiting NAOJ
Fellow Workshop, Element Genesis and Cosmic Chemical Evolution: r-process perspective, 17-19
Oct., 2012, Wako, RIKEN Nishina Center, Japan. (Invited talk)2.

Akira Ozawa, Rare-RI Ring for mass measurements of exotic nuclei, A workshop on Science withRare Ion Beams SCRIBE-2012, Variable Energy Cyclotron Centre, Sector-1, Block-AF, Bidhan
Nagar (Salt Lake), Kolkata 700064, Inida, 7-9 Nov., 2012. (Invited talk)3.

D. Nagae, T. Niwa, Y. Ishibashi, Y. Abe, S. Fukuoka, R. Nishikiori, S. Okada, Y. Saito, N. Inaba, A.
Ozawa, Y. Aoki, Development of rotating magnetic field system for  the  β-NMR method, The 4th
Joint Meeting of the International Symposium on Hyperfine Interactions and the International
Symposium on Nuclear Quadrupole Interactions (HFI/NQI 2012)

4.

D. Nagae, Y. Abe, S. Okada, A. Ozawa, T. Yamaguchi, H. Suzuki, T. Moriguchi, Y. Ishibashi, S.
Fukuoka, R. Nishikiori, T. Niwa, T. Suzuki, F. Suzaki, K. Sato, H. Furuki, N. Ichihashi, S. Miyazawa,
Y. Yamaguchi, T. Uesaka, M. Wakasugi, Time-of-flight detector applied to mass measurements in
Rare-RI Ring, 16th International Conference on Electromagnetic Isotope Separators and Techniques
Related to their Applications (EMIS2012)

5.

Kimikazu Sasa, The 6 MV tandem accelerator project for nuclear physics and ion beam applications
at the University of Tsukuba, The 8th China-Japan Joint Nuclear Physics Symposium, 15-19 Oct.,2012, Beijing International Convention Center, Beijing, China. (Invited talk)6.

Kimikazu Sasa, Damage Situation of the 12UD Pelletron tandem accelerator at the University ofTsukuba by the Great East Japan Earthquake, 12th Heavy Ion Accelerator Technology Conference(HIAT2012), Chicago, Illinois USA, June 18-21, 2012.

7.

K. Sasa, T. Takahashi, N. Nagashima, and K. Shima, Isotope Dependence of the Equilibrium Charge
State of Cl Ions Passing through Carbon Foils, 25th International Conference on Atomic Collisions in
Solids, October 21-25, 2012 Kyoto, Japan.

8.

T. Komatsubara, Gamma-ray spectroscopy on 26Si -- By pass sequence for 26Al production --, New
Frontiers in Nuclear Astrophysics, 18-22 June, 2012, Castiglion Fiorentino, Italy.

9.

T. Komatsubara, A. Ozawa, T. Moriguchi, Y. Ito, Y. Ishibashi, Y. Abe, T. Yuasa, T. Hayakawa, T.
Shizuma, K. Y. Hara, S. Kubono, H. Yamaguchi, D. Kahl, S. Hayakawa, Dam N. Binh, A. A. Chen, J.
Chen, K. Setoodehnia, T. Kajino, Study of level structure on 26Si for the astrophysical interest in 26Al

43

production, The XII International Symposium on Nuclei in the Cosmos, Proceedings of Science,
XII_206, (2012), 5-10 Aug., 2012, Cairns, Australia.
10. T. Komatsubara, A. Ozawa, K. Sasa, P. Schury, D. Nagae, Y. Ito, Y. Ishibashi, Y. Abe, S. Fukuoka, R.
Nishikiori, T. Niwa, H. Mita, Y. Saito, S. Okada, T. Yuasa, T. Onishi, A. Terakado, T. Hayakawa, T.
Shizuma, S. Kubono, Recent research activities of nuclear astrophysics in University of Tsukuba, The
XII International Symposium on Nuclei in the Cosmos, Proceedings of Science, XII_168, (2012),
5-10 Aug., 2012, Cairns, Australia.
11. T. Onishi, T. Komatsubara, T. Yuasa, T. Hayakawa, T. Shizuma, S. Kubono, The study of
nucleosynthesis by means of scandium45+p reaction, Poster presentation, The XII International
Symposium on Nuclei in the Cosmos, Proceedings of Science, XII_219, 5-10 Aug., 2012, Cairns,
Australia.
12. T. Komatsubara, Origin of 26Al, Element Genesis and Cosmic Chemical Evolution, NAO RIKEN
workshop, 17-10 Oct., 2012, RIKEN, Japan.
13. A. S. Demyanova, A. N. Danilov, S. V. Dmitriev, A. A. Ogloblin, S. A. Goncharov, N. Burtebaev, J.
Burtebaeva, N. Saduev, T. L. Belyaeva, H. Suzuki, R. Nishikiori, A. Ozawa, D. Nagae, T. Moriguchi,
Y. Ishibashi, H. Ooishi, K. Yokoyama, Y. Abe, K. Okumura, S. Fukuoka, S. Ito, T. Niwa, T.
Komatsubara, S. Kubono, Search Neutron Halo in 9Be Excited States, Contrib.61st International
Conf. "Nucleus-2011" on Problems of Nuclear Spectroscopy and Structure of Atomic Nucleus, p.66
(2011), Sarov.
14. S. Hayakawa, S. Kubono, D. Kahl, H. Yamaguchi, D. N. Binh, T. Hashimoto, Y. Wakabayashi, J. J.
He, N. Iwasa, S. Kato, T. Komatsubara, Y. K. Kwon, T. Teranishi, S. Wanajo, Direct measurement of
the 11C (α,  p) 14N reaction at CRIB: A path from pp-chain to CNO, Proc.Carpathian Summer Schoolof physics 2012, Exotic Nuclei and Nuclear Particle, Astrophysics IV, 24 June-7 July, 2012, L.Trache,
P.G.Isar, Eds. p.339 (2012), AIP Conf.Proc.1498 (2012), Sinaia, Romania.
15. D. Sekiba, Y. Narita, S. Harada, S. Ogura, K. Fukutani, NRA for hydrogen analysis in atmosphericcondition, 25th International Conference on Atomic Collisions in Solids, 21-25 October, 2012, Kyoto,
Japan.
16. D. Sekiba, Y. Narita, S. Harada, M. Matsumoto, S. Ogura, H. Matsuzaki, K. Fukutani, Direct
Observation of Novel Hydrogen Uptake in Nano-scale superlattice of Mg thin film by ambient NRA,
16th International Conference on Solid Films and Surfaces, 1-6 July, 2012, Genoa, Italy.

44

17. Y. Shiina, S. Tamura, I. Harayama, K. Yamazaki, K. Sasa, S. Ishii, and S. Tomita, Coincidence
Measurement of Secondary Electrons with Scattered Ions under Irradiation of Fast Carbon-Cluster
Ions, 25th International Conference on Atomic Collisions in Solids, 21-25 October, 2012, Kyoto,
Japan.
18. S. Tomita, H. Tsuchida, Y. Shiina, R. Kinoshita, J. Yokoe, K. Yamazaki, S. Ishii, and K. Sasa,
Transmission of Fast Carbon Cluster Ions through an Al2O3 Nano-Capillary Foil, 25th International
Conference on Atomic Collisions in Solids, 21-25 October, 2012, Kyoto, Japan.
19. T. Nogami, C. Penny, L. Tai, C. Parks, P. Flaitz, A. Uedono, A. Simon, T. Bolom, C. Christiansen, A.
Madan, J. Li, F. Baumann, R. Davis, T. Ryan, F. Ito, S. Choi, J. Kelly, M. He, X. Zhang, H. Kim, R.
Murphy, S. Molis, J. Rowland, P. Dehaven, K. Tanwar, D. Canaperi, C-K. Hu, S. Chiang, T. Spooner,and D. Edelstein, Electromigration extendibility of Cu(Mn) alloy-seed interconnects andunderstanding the fundamentals, Int. Electron Devices Meeting, 10 Dec., 2012, San Francisco, CA,
USA.
20. S. F Chichibu, K. Hazu, Y. Ishikawa, M. Tashiro, H. Miyake, K. Hiramatsu, and A. Uedono, Impactsof point defects on the photoluminescence lifetime of Si-doped Al0.6Ga0.4N epilayers grown on an
AlN template, Int. Workshop on Nitride Semiconductors, 18 Oct., 2012, Sapporo, Japan.
21. T. Araki, N. Uematsu, M. Yutani, J. Sakaguchi, K. Wang, A. Uedono, T. Fujishima, E. Matioli, T.
Palacios, and Y. Nanishi, Growth of high quality thin InN layers by RFMBE, Int. Workshop on
Nitride Semiconductors, 16 Oct., 2012, Sapporo, Japan.
22. K. Furusawa, Y. Ishikawa, M. Tashiro, K. Hazu, S. Nagao, K. Fujito, A. Uedono, and S. F. Chichibu,
Local carrier dynamics in freestanding GaN substrates grown by hydride vapor phase epitaxy studied
using the spatio-time-resolved cathodoluminescence technique, Int. Workshop on Nitride
Semiconductors, 15 Oct., 2012, Sapporo, Japan.
23. K. Patil, S. Sellaiyan, T. Lin , X. Wang , S.V. Smith, and, A. Uedono, Effect of animal protein fibre
milling on free volume by positron annihilation lifetime spectroscopy, 16th Int. Conf. on Positron
Annihilation, 22 Aug., 2012, Bristol, UK.
24. W. Zhou, N. Oshima, Z. Chen, K. Ito, B. E. O’Rourke, R. Kuroda R. Suzuki, H. Yanagishita, T.
Tsutsui, A. Uedono, and N. Hayashizaki, Development of the humidity controlled atmospheric PPMA,
16th Int. Conf. on Positron Annihilation, 22 Aug., 2012, Bristol, UK.
25. A. Uedono, Y. Dordi, S. Li, G. Mizunaga, K. Tenjinbayashi, N. Oshima, and R. Suzuki,
Agglomeration and dissociation of vacancies in electroless deposited Cu films studied by45

monoenergetic positron beams, 2012 IEEE Int. Interconnect Tech. Conf., 5 June, 2012, San Jose,USA.
26. A. Sagara, M. Hiraiwa, A. Uedono, and S. Shibata, Detection and characterization of residual damage
in low-dose arsenic implanted silicon after high-temperature annealing, 12th Int. Workshop on
Junction Technology, 14 May, 2012, Shanghai, China.
27. M. Takahashi, W. Konishi and K. Ohshima, The electron density   distribution   in   α-Sn, AsCA
12/CRYSTAL 28 Conference and BRAGG Symposium, 3 Dec., 2012, Adelaide.
28. Yasushi Kanke, Takuro Yoshikawa, Hideto Yanagihara, Eiji Kita, Yorihiko Tsunoda, Kiiti Siratori and
Kay Kohn, Formation of stoichiometric of FeO synthesized under high pressure, 19th International
Conference on Magnetism (ICM 2012), 8-13 July, 2012, Busan.
29. D. Isaka, Y. Kikuchi, A. Seki, Ka. Suzuki, M. Kishimoto, H. Yanagihara, E. Kita, Effects of viscosityof ferromagnetic dispersant on specific loss power, International Conference of the Asian Union ofMagnetic Societies (ICAUMS 2012), 2pPS-119, 2-5 Oct., 2012, Nara.
30. Daichi Oka, Yasushi Hirose, Hideyuki Kamisaka, Tomoteru Fukumura, Tetsuya Hasegawa, Seiji Ito,
Akira Morita, Hiroyuki Matsuzaki, Katsuyuki Fukutani, Satoshi Ishii, Kimikazu Sasa, Daiichiro
Sekiba, Dielectric properties of perovskite oxynitride epitaxial thin films, APS March Meeting 2013,
March 18 - 22, Baltimore, Maryland, USA.

46

7.

THESES

Master’s theses
Ryo FUNATO

Multiplicity dependence of 2-particle correlation in 200GeV p-p collisions
with pythia simulation

Kaoru GUNJI

Azimuthal dependence of 2-particle interferometry in √scollisions at LHC-ALICE experiment

Satoshi HORIUCHI

Reaction plane and azimuthal anisotropy measurements with participants
and spectators in √s =2.76TeV Pb-Pb collisions at LHC-ALICE
experiment

Hiroshi NAKAGOMI

Pseudo-rapidity dependence of azimuthal anisotropy with silicon vertex
detector in √s =200GeV Au-Au collisions at RHIC-PHENIX experiment

Daisuke WATANABE

Azimuthal correlation of pi0-jet in √s
at LHC-ALICE experimentToshiaki YUASA

Measurement of the astrophysical S-factor for the 7Li(3He, p0) 9Be reaction

Takahiro NIWA

Developments of apparatus to determine the sign of nuclear magnetic
moments for radioactive nuclei

Ryou NISHIKIORI

Measurements of Charge-Changing Cross Sections for Ca Isotopes andDeduction of Charge Radii

Hiroki MITA

Surface current electrostatic lens for an ion guide gas cell=2.76TeV Pb-Pb=2.76TeV p-p and Pb-Pb collisions

Undergraduate theses
Tomo NAKAJIMA

Radon detector for radiological education - Development of teaching material
and practical approach –

47

8.
2012
May 14SEMINARS
Rare-RI Ring Project – toward of investigation for r-process nucleosynthesis -, Akira Ozawa(University of Tsukuba)

Jul 18

Electron momentum distribution of organic crystals by 2D-ACAR and Leaching properties ofself-healing paint for anti corrosion application, Selvakumar Sellaiyan (University ofTsukuba)

Aug 29Positron Beamlines for Materials Studies and Atomic and Molecular, James Sullivan(Australian National University)

Nov 8

Neutron halos in excited states of stable nuclei, Prof. A. Ogloblin (Kurchatov Institute,
Moscow, Russia)

Dec 19Precise measurement of elliptic anisotropy with an upgraded detector and quark number
scaling at   √sNN =200GeV Au+Au in RHIC-PHENIX, Yosimasa Ikeda (RIKEN)
Measurements of azimuthal correlation between jet and charged particle at LHC-ALICE
experiment, Dousatu Sakata (University of Tsukuba)

Dec 20Measurements of Hanbury-Brown and Twiss effect with respect to the event plane in
relativistic heavy ion collisions at RHIC-PHENIX, Takafumi Niida (University of Tsukuba)
Measurements of Anisotropic Flow for Identified Hadrons in   √sNN =2.76TeV Pb + Pb
Collisions at LHC-ALICE, Masato Sano (University of Tsukuba)

Dec 212013
Jan 15

Mearsurments of higher-order flow harmonics and two particle, Takahito Todoroki(University of Tsukuba)

Multiplicity dependence of 2-particle correlation in 200GeV p-p collisions with pythia
simulation, Ryo Funato (University of Tsukuba)Radon detector for radiological education - Development of teaching material and practical
approach –, Tomo Nakajima (University of Tsukuba)
Measurements of Charge-Changing Cross Sections for Ca Isotopes and Deduction ofCharge Radii, Ryou Nishikiori (University of Tsukuba)

Jan 16

Azimuthal correlation of pi0-jet in √s =2.76TeV p-p and Pb-Pb collisions at LHC-ALICE
experiment, Daisuke Watanabe (University of Tsukuba)
Surface current electrostatic lens for an ion guide gas cell, Hiroki Mita (University ofTsukuba)
Reaction plane and azimuthal anisotropy measurements with participants and spectators in√s =2.76TeV Pb-Pb collisions at LHC-ALICE experiment, Satoshi Horiuchi (University ofTsukuba)

Jan 18Azimuthal dependence of 2-particle interferometry in √s =2.76TeV Pb-Pb collisions at
LHC-ALICE experiment, Kaoru Gunji (University of Tsukuba)

48

Jan 18

Developments of apparatus to determine the sign of nuclear magnetic moments forradioactive nuclei, Takahiro Niwa (University of Tsukuba)
Pseudo-rapidity dependence of azimuthal anisotropy with silicon vertex detector in√s =200GeV Au-Au collisions at RHIC-PHENIX experiment, Hiroshi Nakagomi(University of Tsukuba)
Measurement of the astrophysical S-factor for the 7Li(3He, p0) 9Be reaction, Toshiaki Yuasa(University of Tsukuba)

Feb 28

Research program at the RCNP cyclotron facility, Kichiji Hatanaka (Osaka University)

49

9.

SYMPOSIUM=== A debrief meeting of the Pre-Strategic Initiatives ===Inclusive liaisons around UTTAC on the recent researches and innovational uses
by using accelerated ion beams and radioactive sources.
18 March 2013
Laboratory of Advanced Research B 0110

1. Openning : E. Kita (University of Tsukuba)
2. Status and future prospects of the 6 MV tandem accelerator project at the University of Tsukuba:
K. Sasa (University of Tsukuba)
3. Study of nucleosynthesis by using 1MV tandetron: T. Komatsubara (University of Tsukuba)
4. Rare RI Ring: D. Nagae (University of Tsukuba)
5. High-Precision Mass Measurements at RIKEN with Multi-Reflection Time-of-Flight Mass
Spectrograph: Peter Schury (University of Tsukuba)
6. Transport properties of chromate-containing self healing epoxy films using radiotracer, PALS andSEM: Selvakumar Sellaiyan (University of Tsukuba)
7. Recent studies on hydrogen in materials and renewal of hydrogen analysis systems: D. Sekiba(University of Tsukuba)
8. Development of E-E telescope ERDA for light element analysis: I. Harayama (University ofTsukuba)
9. Nitrogen doping-concentration dependence in the amorphous insulator AlN for spintronics: R.
Akiyama (University of Tsukuba)
10. Outline of irradiation facilities and their utilization sharing at JAEA Takasaki institute: W. Yokota(JAEA)
11. Open Advanced Research Facilities Initiative at JAEA Takasaki site: A. Yamazaki (JAEA)
12. Perpendicular magnetic anisotropy in CoFe2O4 epitaxial thin film: T. Niizeki (University of Tsukuba)

50

13. Evaluation of Radiation Resistance of On-board Microprocessor for University of Tsukuba Cubesat
ITF-1 "YUI": T. Kameda (University of Tsukuba)
14. Closing remarks: T. Komatsubara (University of Tsukuba)

51

10.

LIST OF PERSONNEL

Tandem Accelerator Complex
E. Kita

Director, Professor

K. Sasa

Associate Professor

T. Komatsubara

Assistant Professor

D. Sekiba

Assistant Professor

H. KimuraComputer Engineer

H. Oshima

Electric Engineer

Y. Tajima

Mechanical Engineer

S. Ishii

Mechanical Engineer

T. Takahashi

Electric Engineer

Y. YamatoElectric Engineer

S. Selvakumar

Research Fellow

Y. Tagishi

Research Supporter

K. Iitake

Administrative Stuff

N. YamadaAdministrative Stuff

S. AbeAdministrative Stuff

Research Members1
Inst. of Physics
I. AraiT. Komatsubara

K. Sasa

P. Schury

D. Nagae

A. Ozawa

Inst. of Applied Physics
K. Akimoto

S. Aoki

E. Kita

M. Minagawa

D. Sekiba

T. Suemasu

S. Tomita

A. Uedono

H. Yanagihara
Inst. of Materials Science
T. Kondo

M. Takahashi

Inst. of Engineering Mechanics and Systems
K. Matsuuchi
1

The “research members” include the authors and coauthors within 5 years back from this fiscal year, as well as themembers of research projects running at UTTAC.

52

Inst. of Geoscience
M. Kurosawa
Inst. of Chemistry
K. Sueki
Staff of Open Advanced Facilities Initiative
H. KudoS. LeeH. Naramoto

M. Matsumura

H. Muromachi

Graduate students
Doctoral Programs of Pure and Applied Science
Y. AbeS. Fukuoka

Y. Ishibashi

K. ItoY. ItoY. Kiguchi

K. Kurita

K. Suzuki

Master’s Programs of Pure and Applied Science
K. Chito

S. Funada

N. Inaba

D. Isaka

M. IuraI. Harayama

S. Kimura

H. Mita

A. Mori

M. Myouka

M. MukaiR. Nishikiori

T. Niwa

S. Okada

T. Onishi

Y. Saito

Y. Shiina

N. Takemoto

T. Tsutsui

M. UehiraY. Yamashita

K. Yamazaki

Z. Yang

S. Yoshimatsu

T. Yuasa

Y. Watahiki

T. Watanabe

Master’s Programs of Life and Environmental Science
M. Ishikawa

Y. SatoUndergraduates
R. Aoyama

S. Aldyyarov

F. AraiA. Horiuchi

D. Izumi

R. Kinoshita

K. Kitajima

K. Nakashima

K.Sawahata

N. Shibayama

S. Shohata

A. Terakado

R. Watanabe

N. Yoshihara

53

Scientific Gutests and Fellows
K. Awazu

National Institute of Advanced Industrial Science and Technology (AIST)

M. Fujimaki

National Institute of Advanced Industrial Science and Technology (AIST)

Y. Tosaki

National Institute of Advanced Industrial Science and Technology (AIST)

T. Hayakawa

Japan Atomic Energy Agency (JAEA)

T. Shizuma

Japan Atomic Energy Agency (JAEA)

S. KubonoCenter for Nuclear Study, Univ. of Tokyo (CNS)

A. SatoOsaka Univ.

A. Yamamoto

High Energy Accelerator Research Organization (KEK)

T. AdachiHigh Energy Accelerator Research Organization (KEK)

M. YoshidaHigh Energy Accelerator Research Organization (KEK)

N. Kawamura

High Energy Accelerator Research Organization (KEK)K. Shimomura

High Energy Accelerator Research Organization (KEK)

P. Strasser

High Energy Accelerator Research Organization (KEK)

T. Nakamoto

High Energy Accelerator Research Organization (KEK)

M. IioHigh Energy Accelerator Research Organization (KEK)K. YoshimuraHigh Energy Accelerator Research Organization (KEK)54