HHIQCD2015

Experimental spectroscopy of
pionic atoms and eta'-mesic nuclei
Kenta Itahashi

HHIQCD2015

Mass of PS mesons[MeV/c2]1000η′M=958 MeV/c2750η

M=548 MeV/c2
2
M=498
MeV/c
K

500
250

2
M=140
MeV/c
π

Kenta Itahashi, RIKEN

pdg

0
2

HHIQCD2015[MeV/c2]

Mass of PS mesons+ explicit χs breaking

1000

dynamical χ symmetry 	breaking

η0750

UA(1) anomalyχ symmetry 	

manifests

500

π,K,η8,η0250
π,K,η8Another picture appears in 	

Klimt et al., NPA516(1990)429.

massless

Kenta Itahashi, RIKEN

0

Nagahiro et al., PRC 87 (2013) 045201	

Jido et al., NPA 914 (2013) 354

3

HHIQCD2015

Contents•

piAF project (RIBF-54) at RIBF
Physics
Pilot run 2010 and achievements
Main run 2014
Challenges for piA with unstable nuclei"•

EtaPrime (GSI-S437) at GSI/FAIR
Physics and strategy

Detail in next talk

Pilot run 2014
Future perspectives

Kenta Itahashi, RIKEN

4"

HHIQCD2015

Precision measurement of deeply boundpionic Sn atoms in RIBF
Kenta Itahashi

Advanced Meson Science Laboratory, RIKEN
for piAF
RILACcollaboration
DeukSoon Ahn, Georg P. A. Berg, Masanori Dozono, Hiroyuki Fujioka, Naoki Fukuda,
Nobuhisa Fukunishi, Hans Geissel, Emma Haettner, Ryugo S. Hayano, Satoru Hirenzaki,
AVF
HiroshiRIPS
Horii, Natsumi Ikeno, Naoto Inabe, Kenta Itahashi*, Masahiko Iwasaki,
Daisuke Kameda, Nobuyuki Kobayashi, Toshiyuki Kubo, Hiroaki Matsubara, Shin’ichiro Michimasa,
Kenjiro Miki, Go Mishima, Daichi Murai, Hiroyuki
Miya, Hideko Nagahiro, Megumi Niikura,
SRC
Takahiro Nishi**, Shumpei Noji,RRCShinsuke Ota, Haruhiko Outa, Naruhiko Sakamoto,fRC
Hiroshi Suzuki, Ken Suzuki, Motonobu Takaki, Hiroyuki Takeda,
Yoshiki K. Tanaka,
BigRIPS
Tomohiro Uesaka, Yuni N. Watanabe, Helmut Weick, Hiroki Yamakami, Koichi Yoshida.
IRC* spokesperson, ** co-spokesperson
RIKEN Nishina Center, RIKEN
Department of Physics, University of Notre Dame
050 m
Department of Physics, Kyoto University
GSI Helmholtzzentrum fuer Schwerionenforschung GmbH
Department of Physics, The University of Tokyo
Department of Physics, Nara Women's University
National Institute of Radiological Sciences
Center of Nuclear Study, The University of Tokyo
Research Center for Nuclear Physics, Osaka University
National Superconducting Cyclotron Laboratory, Michigan State University
Stefan-Meyer-Institut für subatomare Physik, Österreichische Akademie der WissenschaftenPionic Atoms and piA interaction

HHIQCD2015

π−pion wave function locates	

at vicinity of nucleus
sensitivity to	0.6ρ0π-nucleus s-wave potential

Vs-wave = b0 ρ + b1 (ρn − ρp) + B0 ρ2

for ρe= 0.6 ρ0Kenta Itahashi, RIKEN

N. Ikeno et al., PTP126(2011)483.

6

HHIQCD2015

Chiral symmetry at finite density
Jido, Hatsuda, Kunihiro, Phys.Lett.B670:109-113,2008.	

Kolomeitsev, Kaiser, Weise, Phys. Rev. Lett. 90(2003)092501	

M. Gell-Mann et al., PR175(1968)2195.

Gell-Mann-Oakes-Renner relation–|<qq>|f m =2-(250 MeV)32

2mq q̄qf : pion decay constant-35%

Y. Tomozawa, NuovoCimA46(1966)707.	

S. Weinberg, PRL17(1966)616.

Tomozawa-Weinberg relation

Normal Nuclear
Density

300 MeV
T

b1 =

5ρ0

ρ

m
8 f2

b1: isovector πN scattering length

q̄q
q̄q 0

Kenta Itahashi, RIKEN

bfree
1b1 ( )
7

HHIQCD2015

Present b1 precision
−0.14

−0.13

−0.12

−0.11

−0.10

−0.09

b1

Pb-1s
In-medium b1*

Sn-1s 	

+ Si, Ne, O

In-vacuum b1

b1* still has a large error

K. Suzuki et al., 	

PRL92(04)072302.

Vs-wave = b0 ρ + b1 (ρn − ρp) + B0 ρ2← spectroscopy of pionic atoms
In-medium b1 is calculated based on deeply bound pionicstates data combined with light spherical pionic atom data.

Kenta Itahashi, RIKEN

8Spectroscopy of pionic atoms

HHIQCD2015(d,3He) nuclear reaction	

to directly produce deeply	bound pionic atom i.e. hidden 	states in X-ray spectroscopy

Pion bound state	

Missing mass spectroscopy	

to measure excitation spectrum 	by Q-value measurement

We are aiming at	

300 keV (FWHM) resolution.	

(prev. 400 keV)(coupled with n hole)threshold
quasi
free

3He Kinetic energy

Kenta Itahashi, RIKEN

9

HHIQCD2015

Momentum Transfer

Kenta Itahashi, RIKEN

10Present b1 precision

HHIQCD2015

Calibration1s

Vs-wave = b0 ρ + b1 (ρn − ρp) + B0 ρ2
ρe= 0.6 ρ0
K. Suzuki et al.,PRL92(04)072302.

In-medium b1 is calculated based on deeply bound pionicstates data combined with light spherical pionic atom data.

Kenta Itahashi, RIKEN

11

Present b1 precision

HHIQCD2015

Γ1s
115Sn 0.441

123Sn 0.341

0.087
0.080
0.072

B1s
115Sn 3.906
119Sn 3.820
123Sn 3.744

0.024
0.018
0.018

119Sn 0.326

Vs-wave = b0 ρ + b1 (ρn − ρp) + B0 ρ2
ρe= 0.6 ρ0

K. Suzuki et al.,PRL92(04)072302.

In-medium b1 is calculated based on deeply bound pionicstates data combined with light spherical pionic atom data.

Kenta Itahashi, RIKEN

12

HHIQCD2015

Experimental resolution / systematic errors
Calibration1s

in-situ Calibration	

p(d,3He)pi0
	"using CH2 pasted Sn target

K. Suzuki et al.,PRL92(04)072302.

Resolution ~ 400 keV	(beam p spread, target thickness)	

""Systematic errors	

in absolute energy scale	(calibration, incident energy, dx/dp…)
Figure based on	

data taken at RIBF

We want to improve precision.

HHIQCD2015

Pionic Atom Factory Project in RIBF
Nuclear chart

Calibration

1s

Targets we measured in GSI
K. Suzuki et al.,PRL92(04)072302.

NNDC,BNL

Kenta Itahashi, RIKEN

14

HHIQCD2015

Pionic Atom Factory Project in RIBF

Chains of isotopes and isotones	

+ different quantum levels of
pionic states.
NNDC,BNL

Kenta Itahashi, RIKEN

15

HHIQCD2015

Precision Spectroscopy at RI Beam Factory
RILAC

RIKEN-RIBF
AVF

RIPS

SRC

RRC

fRC

BigRIPS
IRC

0

Target50 m

d beam Intensity
Target
Δ

GSI

RIBF

10

>10

20 mg/cm 10 mg/cm
0.03%

0.1%

Resolution (FWHM)

400 keV1000 keV

Acceptance (mrad)

15H, 10V 40H, 60V

Kenta Itahashi, RIKEN

16

HHIQCD2015

Precision Spectroscopy at RI Beam Factory
RILAC

RIKEN-RIBF
AVF

RIPS

SRC

RRC

fRC

BigRIPS
IRC

0

Target50 m

d beam Intensity
Target
Δ

GSI

RIBF

10

>10

20 mg/cm 10 mg/cm
0.03%

0.1%

Resolution (FWHM)

400 keV1000 keV

Acceptance (mrad)

15H, 10V 40H, 60V

Kenta Itahashi, RIKEN

17

HHIQCD2015

Precision Spectroscopy at RI Beam Factory
RILAC

RIKEN-RIBF
AVF

RIPS

SRC

RRC

fRC

BigRIPS
IRC

0

Target50 m

d beam Intensity
Target
Δ

GSI

RIBF

10

>10

20 mg/cm 10 mg/cm
0.03%

0.06%

Resolution (FWHM)

400 keV>500 keV

Acceptance (mrad)

15H, 10V 40H, 60V

Kenta Itahashi, RIKENSlit optimization

18

HHIQCD2015

Dispersion matching
Spectrometer

x
a

=

s11
s21
0

s12
s22
0

s16
s26
1

Beam position at focal plane

Beam line to Target

T

b11
b21
0

=C 0
C = 1.31

b12
b22
0

b16
b26
1

x0
a0
0

(d,3He)H. Fujita et al., NIMA484(2002)17

x = (s11 b11 + s12 b21 )x0+ (s11 b12 + s12 b22 )a0+ (s11 b16 + s12 b26 + s16 C) 0

TargetDispersion matching conditions11 b16 + s12 b26 + s16 C = 0
s16 C
b16 =
= 44.6 mm/%s11

Kenta Itahashi, RIKEN

19

HHIQCD2015

Ion Optics

T.Nishi

BigRIPS = Spectrometer
Focal Plane	

of tracking point

red : δp = +0.5%"
green : δp = 0%"blue : δp = -0.5%
TargetSRC
Beam
Transferline=
Analyzer
Kenta Itahashi, RIKEN

20

HHIQCD2015

Precision spectroscopy at RI Beam Factory
RILAC

RIKEN-RIBF
AVF

RIPS

SRC

RRC

fRC

BigRIPS
IRC

0

Target50 m

d beam Intensity
Target
Δ

GSI
10

RIBF
10

20 mg/cm 10 mg/cm
0.03%

0.06%

Resolution (FWHM)

400 keV < 300 keV

Acceptance (mrad)

15H, 10V 40H, 60V

Kenta Itahashi, RIKEN

Resol. Matching

21

HHIQCD2015

RIBF-54 Objectives•

2010 Pilot run (~3 days)
Establish experimental methods(calibration, optics, detectors etc.)
Take a short production run w. Sn target for overall test	"•2014 Main run (~10 days)
Achieve world highest resolution < 400 keVFirst observation of 1s + 2s pionic Sn states→ better precision + better sys. error for B and ΓFirst data for pionic even N Sn atom
Kenta Itahashi, RIKEN

22

HHIQCD2015

Pionic Atom Factory Project in RIBF

First Experiment
NNDC,BNL

Kenta Itahashi, RIKEN

23

Prepared targets

HHIQCD2015

122Sn 10 mg/cm2"
117Sn 10 mg/cm2"
116Cd 10 mg/cm2

Kenta Itahashi, RIKEN

24

HHIQCD2015

122
3
Theoretical Spectrum for Sn(d, He)
122Sn(d,3He)	

μb/sr/MeV

0 degreeQ-freeN. Ikeno, Eur.Phys.J. A47 (2011) 161

Kenta Itahashi, RIKEN

25

HHIQCD2015

Experimental setup
TOF measurement

ΔE measurement

BigRIPS
p 105 /s

F7

Scintillator

F5

3He Tracking

3He 102 /s

MWDC x 2	

Scintillator

TargetSRC

Dispersive focal planed beam >1012 /s, 250 MeV/u
Kenta Itahashi, RIKEN

26

HHIQCD2015

Experimental setup
TOF measurement

ΔE measurement

BigRIPS
p 105 /s

F7

Scintillator
3He Tracking

3He 102 /s

F5

MWDC x 2	

Scintillator

TargetSRC

d beam >1012 /s, 250 MeV/u
Kenta Itahashi, RIKEN

27

Particle identification
30000

HHIQCD2015

TOF:	

between F5 and F7	

Energy loss:	

at F5 scintillators

20000

10000

Time of flight [ns]0240deuteron
220
200
180
160

3

He

proton140

800 1000 1200 1400

Energy loss [a.u.]

Kenta Itahashi, RIKEN

30000

600

20000

400

10000

200

0

120
0

RIBF-5428

HHIQCD2015

Focal Plane 3He Spectrum in 2010	

(acceptance roughly corrected)
2400

3He)
1221223Sn(d,Sn(d, He)

2200

data accumulation	

with 1012/s beam	

for pilot exp.

1800

Counts/0.5 mm

15 hours(15 hours)

2000

1600
1400
1200
1000
800
600
400
-100

N. Ikeno, Eur.Phys.J. A47 (2011) 161

-50
0
50
3
Horizontal position of He [mm]low p3He

Kenta Itahashi, RIKEN

100

hi p3He

RIBF-54
29

HHIQCD2015

Focal Plane 3He Spectrum in 2010	

(acceptance roughly corrected)
2400
2200

data accumulation	

with 1012/s beam	

for pilot exp.

(15 hours)

1800

Counts/0.5 mm

15 hours

2000

Threshold3He)
1221223Sn(d,Sn(d, He)

1600
1400
1200

Free

Bound

1000
800
600
400
-100

N. Ikeno, Eur.Phys.J. A47 (2011) 161

-50
0
50
3
Horizontal position of He [mm]low p3He

Kenta Itahashi, RIKEN

100

hi p3He

RIBF-5430

HHIQCD2015

Focal Plane 3He Spectrum in 2010	

(acceptance roughly corrected)
2400
2200

data accumulation	

with 1012/s beam	

for pilot exp.

Threshold

1800

Counts/0.5 mm

15 hours

2000

2s,2p
2p

1600
1400
1200

3He)
1221223Sn(d,Sn(d, He)Free

(15 hours)

Bound
1s

1000
800
600
400
-100

N. Ikeno, Eur.Phys.J. A47 (2011) 161

-50
0
50
3
Horizontal position of He [mm]low p3He

Kenta Itahashi, RIKEN

100

hi p3He

RIBF-54
31

HHIQCD2015

Achievements in pilot run 2010 and goals for main run 2014
Achievements in 2010
All system works & surprisingly good statistics in a short time	

First observation of pionic 121Sn	

First observation of angular dependence of piA formation	(however w. insufficient calibration/correction data…)	

"Goals for 2014
Achieve better resolution	

Take calibration / acceptance / aberration correction data	Attempt to systematic study

Kenta Itahashi, RIKEN

32

HHIQCD2015

Improvements in 2014"

incident beam (dp/p, Id), beam optics, detectors, DAQ,/online…

Kenta Itahashi, RIKEN

33

Online spectrum from 2014
2014

HHIQCD2015

122Sn(d,3He)

Acceptance not corrected"
Higher order aberration roughly corrected

3He energy Smaller

Focal Plane Position [mm]Kenta Itahashi, RIKEN

3He energy Larger

RIBF-54
34

Online spectrum from 2014
2014

HHIQCD2015

2400
2200
2000
Counts/0.5 mm

1800
1600
1400
1200
1000

122Sn(d,3He)2010
Acceptance "roughly "corrected

800
600
400
-100

-50
0
50
Horizontal position of 3He [mm]100

Acceptance not corrected"
Higher order aberration roughly corrected

3He energy Smaller

Focal Plane Position [mm]Kenta Itahashi, RIKEN

3He energy Larger

RIBF-54
35

Online spectrum from 2014
2400

HHIQCD2015

122Sn(d,3He)
122Sn(d,
3He)

2200
2000

2010

Counts/0.5 mm

1800
1600

Acceptance "roughly "corrected

1400
1200
1000
800
600
400
-100

-50
0
50
Horizontal position of 3He [mm]100

Acceptance curve (eye-guide)

Free

Bound

Acceptance not corrected"
Higher order aberration roughly corrected

3He energy Smaller

Focal Plane Position [mm]Kenta Itahashi, RIKEN

3He energy Larger

RIBF-5436

Online spectrum from 2014
2400
2200
2000
1800

Counts/0.5 mm

2p
1s
2s,2p

1600
1400

Quasi-free pi

1200
1000

HHIQCD2015

122Sn(d,3He)
122Sn(d,3He)

2010
Acceptance "roughly "corrected

800
600
400
-100

Free

-50
0
50
Horizontal position of 3He [mm]

100

Bound

Acceptance not corrected"
Higher order aberration roughly corrected

3He energy Smaller

Focal Plane Position [mm]Kenta Itahashi, RIKEN

3He energy Larger

RIBF-54
37

Measured focal spectrum with angles
2s,2p… 2p

1s

Angle [mrad]

122Sn(d,3He)

HHIQCD2015

3He energy Smaller

Focal Position [mm]Kenta Itahashi, RIKEN

3He energy Larger

RIBF-54
38

Measured focal spectrum with angles

Angle [mrad]

122Sn(d,3He)2s,2p… 2p

HHIQCD2015

1s

We clearly observe theangular dependence 	

(= momentum transfer
dependence) of pionic atom
production cross section in(d,3He) reaction

3He energy Smaller

Focal Position [mm]Kenta Itahashi, RIKEN

3He energy Larger

RIBF-54
39

122Sn(d,3He)

Theory vs Experiment (2014)

HHIQCD2015

0 deg

0.5 deg

1 deg*N. Ikeno et al., Eur. Phys. J. A 47, 161 (2011)

Kenta Itahashi, RIKEN

Focal Position [mm]RIBF-5440

122Sn(d,3He)

HHIQCD2015
Theory and exp. basicallyagree.	

Very good resolution at 0 degree.	

The analysis still take time.

Theory vs Experiment (2014)

0 deg

0.5 deg

1 deg*N. Ikeno et al., Eur. Phys. J. A 47, 161 (2011)

Kenta Itahashi, RIKEN

Focal Position [mm]RIBF-54
41

HHIQCD2015

First observation with an even neutron number nucleus
Online spectrum from 2014

Ikeno et al., Prog. Theor. Exp. Phys. 2013 , 063D01

117Sn(d,3He)
θ < 10 mrad"no acc. correction

1s

3He energy "smaller

Focal Position [mm]3He energy "higherFirst observation of pionic atom with even N "→ better separation in the neutron hole configurations.

Kenta Itahashi, RIKEN

N. Ikeno (Hadron 2013)

RIBF-5442

HHIQCD2015

Summary for piAF
• World highest resolution	

• Extremely good statistics for 121Sn-pi	

• First data for pionic even N atom	

• Analysis is ongoing now (by T. Nishi)	

• Publish 2010 results in short

Kenta Itahashi, RIKEN

43

HHIQCD2015

Let me touch on a new subject before etaprime.

Feasibility study has started for

Deeply-Bound Pionic Atoms
with Unstable Nuclei

Y.N. Watanabe

Kenta Itahashi, RIKEN

44

Deeply-Bound Pionic Atoms
with Unstable Nuclei

HHIQCD2015

neutron rich nucleus
π−

0.6ρ0

neutron skin
Pion bound at ρ < 0.6 ρ0
ρ0 : normal nuclear density
Density dependenceof<qq>
N. Ikeno et al., PTP126(2011)483.

~ 0.6 ρ0

HHIQCD2015

Momentum Transfer

CM Kinematics must be conserved.

Kenta Itahashi, RIKEN

46

Missing mass spectroscopy3
in d(HI, He) reaction

HHIQCD2015

Keeping the same kinematical condition 	

as normal kinematics !!
Heavy Ion Beam
~ 250 MeV/u

Pionic Atomπ-n•
3He kinetic energy•
3He recoil angle 	

p
n

3He

Deuteron Targetp pn

THe ~ 60 MeV

Q value

60 MeV 3He range is 1.8 mm in Silicon
Kenta Itahashi, RIKEN

47

HHIQCD2015

Conceptual design at RIBF
as a first step

Kenta Itahashi, RIKEN

48

Experimental Setup

HHIQCD2015

Silicon Detector (Micron W1)

pure D2 MWDC

Heavy Ion
Beam

3

•
3He kinetic energy 	

••vertex point
3He recoil angle 	

He

○

B×

ΔE, Full Energy by Si + 	Trajectory by MWDC	

6
Incident beam < 10 /s

Kenta Itahashi, RIKEN

49

HHIQCD2015

cf. 400 keV for normal kinematics

Kenta Itahashi, RIKEN

50

Detector Development
Silicon in deuterium test 	

+ pure deuterium GEM-TPC	

(w. CNS) development.

HHIQCD2015

prototype MWDC in construction

First test run with	

stable nuclei in HIMAC
Y.N. Watanabe and S. Ogawa

Kenta Itahashi, RIKEN

51

HHIQCD2015

Detector Design
signal30	
  cm
Swagelok

HV

40	
  cm

・Wire feedthrough, hexagonal wire geometry	・Raw material is Al	

・Side walls are flange
Kenta Itahashi, RIKEN

52

HHIQCD2015

Detector Design

silicon	  strip	
  detectorα	  source

・Inside	  the	
  drift	
  chamber,	
  SSD	
  and	  α	  source	
  were	  installed

Kenta Itahashi, RIKEN

53

HHIQCD2015

Summary for pionic unstable atoms•

Started feasibility study for pionic atoms with unstable nuclei	

•Chance to approach chiral condensate at different density	

•

Testing with pure hydrogen active target MWDC now	•

Possible alternative setups are also in consideration

Kenta Itahashi, RIKEN

54

HHIQCD2015

Spectroscopy of η′ mesic nuclei
Y. Ayyad, J. Benlliure, K.-T. Brinkmann, S. Friedrich, H. Fujioka**, H. Geissel, J. Gellanki,
C. Guo, E. Gutz, E. Haettner, M. N. Harakeh, R. S. Hayano, Y. Higashi, S. Hirenzaki,
C. Hornung, Y. Igarashi, N. Ikeno, K. Itahashi*, M. Iwasaki, D. Jido, N. Kalantar-Nayestanaki,
R. Kanungo, R. Knoebel, N. Kurz, V. Metag, I. Mukha, T. Nagae, H. Nagahiro, M. Nanova,
T. Nishi,H. J. Ong, S. Pietri, A. Prochazka, C. Rappold, M. P. Reiter, J. L. R. Sánchez,
C. Scheidenberger, H. Simon, B. Sitar, P. Strmen, B. Sun, K. Suzuki, I. Szarka, M. Takechi,
Y. K. Tanaka, I. Tanihata, S. Terashima, Y. N. Watanabe, H. Weick, E. Widmann, J. Winﬁeld,
X. Xu, H. Yamakami, J. Zhao!
!
for Super-FRS collaboration*spokesperson, ** co-spokesperson!
Osaka University, Universidade de Santiago de Compostela, Universitaet Giessen, Kyoto University, GSI,
University of Groningen, Beihang University, The University of Tokyo, Nara Women's University, KEK,
RIKEN, Tokyo Metropolitan University, Saint Mary’s University, Technische Universitaet Darmstadt,
Comenius University Bratislava, Stefan Meyer Institut, Niigata University
Nagahiro, Jido, Fujioka, KI, Hirenzaki, PRC87(13)045201.	

KI, Fujioka et al., PTP 128 (12) 601.

Kenta Itahashi, RIKEN

55

HHIQCD2015

Mass of PS mesons[MeV/c2]1000η′M=958 MeV/c2750η

M=548 MeV/c2
2
M=498
MeV/c
K

500
250

2
M=140
MeV/c
π

Kenta Itahashi, RIKEN

pdg

0
56

HHIQCD2015

Large η′ mass can be explainedUA(1) symmetry breaking term of 	

effective Lagrangianqq̄
6-point vertex

q

q̄
q̄q

time

Kobayashi-Maskawa-’t Hooft-type interaction
Jido, Nagahiro, Hirenzaki,	

PRC85(2012)032201(R)Jido et al., NPA 914 (2013) 354

Kobayashi, Maskawa, PTP44(70)1422	

‘t Hooft, PRD14(76)3432.	

T. Kunihiro, Phys. Lett. B219(89)363.	

Klimt, Lutz, Vogl, Weise, NPA516(90)429.

Kenta Itahashi, RIKEN

57

HHIQCD2015[MeV/c2]

η′ mesic nuclei searchη′

1000
Naive estimation	

shows 30% reductionof |mη′−mη|

η′

30 %

750
η

11C

Q. Mass shift of 	~ 150 MeV/c2 can beobserved in experiment?

500
250

Jido, Nagahiro, Hirenzaki,	

PRC85(2012)032201(R)0
Kenta Itahashi, RIKEN

58

HHIQCD2015

η′ Mesic Nuclei in (p,d) Reaction

next talkη′ transfer reaction + Missing mass measurement

12C

11C

η′

η′ × 11C 	

mesic nuclei

Tp = 2.50 GeV → q ~ 400 MeV/c
KI, Fujioka et al., PTP 128 (12) 601.

Kenta Itahashi, RIKEN

59

HHIQCD2015

Spectrum in Inclusive
Measurement at GSI
Signal12C(p,d)11C

p

η′

d

285000⊗ η′(V , W0)=<(150, 5) MeV
0280000Backgroundp

270000ππcounts/2MeV

275000dπmu

265000πilt

BK

260000Kenta Itahashi, RIKEN

Simulation
-40

-20
0
Excitation Energy [MeV]2060

Principles of Exclusive
Measurement at FAIR Signals

HHIQCD2015

pη′→pη

pdηp
BackgroundpNη′→pπ

d
π

π
π

p

d
π

p

η′NN→pNd
N

Kenta Itahashi, RIKEN

61

Principles of Exclusive
Measurement at FAIR Signals

HHIQCD2015

BackgroundppNη′→pπ

d
π

π
π

d
η

tagging high-momentum protons	

(300-600 MeV)ppη′→pη

pdπpη′NN→pNd
N

Kenta Itahashi, RIKEN

62

Principles of Exclusive
Measurement at FAIR Signals

HHIQCD2015dηtagging high-momentum protons	

(300-600 MeV)ppη′→pη

pp

Nη′→pπd

Y.K. Tanakaπ

3

100 ×1090

η′p→ηp80η′p→πp70

η′pN→pN60

η′p→ππp504030η′NN→pN

d
N

20
10
0
0

p

100

200

300

400

500
600
700
800
Proton Kinetic Energy [MeV]

Kenta Itahashi, RIKEN

63

HHIQCD2015

Summary•

Spectroscopy of meson bound states for pi and η′•in missing mass spectroscopy	

piAF is in a harvest season after long straggling andwill soon start a precision systematic measurement	

Spectroscopy of piA in unstable nuclei is in progress	•η′ is interesting in relation to UA(1) anomaly	•

Just finished first physics run for inclusive (p,d)	

Preparation for exclusive measurement is in progress••

Kenta Itahashi, RIKEN

64