1 st RIBF PAC N ucleus Pionicatom - m eson Advanced Meson Science Laboratory Kenta Ita Strong Interaction -Nucleus (Chiral symmetry in nuclear matter) cision Spectroscopy of Pionic Atoms in (d, 3 He) Nuclear Reactions 130 131 132 133 134 135 136 137 138 139 E xcitation E nergy [M eV ] 0 5 10 15 (3 p,3 d,4 p,...) (1 s ) ( f 5/2 , p 1/2 , p 3/2 ) n -1 -1 (2 p ) ( f 5/2 , p 1/2 , p 3/2 ) n
Precision Spectroscopy of Pionic Atoms in ( d , 3 He) Nuclear Reactions. Strong Interaction p -Nucleus ( Chiral symmetry in nuclear matter). Advanced Meson Science Laboratory Kenta Itahashi. Experimental Principle = Missing Mass Spectroscopy. Nuclear reaction to - PowerPoint PPT Presentation
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1st RIBF PAC
Nucleus
Pionic atom
- meson
Advanced Meson Science Laboratory Kenta Itahashi
Strong Interaction -Nucleus( Chiral symmetry in nuclear matter)
Precision Spectroscopy of Pionic Atoms in (d,3He) Nuclear Reactions
130 131 132 133 134 135 136 137 138 139E xcita tion E nergy [M e V ]
Experimental Principle = Missing Mass Spectroscopy
Nuclear reaction to directly populate pionic atoms.
P ion bound sta te
S. Hirenzaki, H. Toki and T.Yamazaki
1st RIBF PAC
Pion-nucleus interaction is fairly-well determined
0
10
20
30124S n (d ,3H e )
0 1 2 3 4 5B [M eV]
120S n (d ,3H e)
B [MeV]
3 60 3 65 3 7 0
116S n (d ,3H e)
B [M eV]
3He Kinetic Energy [MeV]
0 1 2 3 4 5
0 1 2 3 4 5
0
1 0
2 0
3 0
0
10
20
30
1s
Calibration
Previous experiments and results
Likelihood contour in potential parameters
2001 GSI
PRL K. Suzuki et al. 92 (04) 072302
1st RIBF PACAmbiguity and error can be smaller
2) Likelihood maxima changewith different matter radius models
Strong interaction potential and nuclear density distribution arecoupled.
1) Precision can be improved
Systematic Study Determine strong interaction and nuclear matter distribution with smaller ambiguity.High Resolution Experimental resolution is improved from 400 keV < 200 keV (FWHM)
Goals in the 1st experimentother inputs: c.f. p-scattering data
1st RIBF PAC
Targets to start systematic study
i) Not measured previously ii) Measure chains of isotopes and isotones.iii) First measurement with odd-neutron number nucleusiv) Check whole system by re-measuring 124Sn & 120Sn
Selection criteria
1st RIBF PAC
Experimental SetupBigRIPS as Spectrometer
Beam: 250 MeV/u deuteron beam Intensity=1 x 1012/s p/p = 1 x 10-3
TA-F5: F5 position depends only on missing mass in TA
F5
1st RIBF PAC
FY 2006-3
FY 2006-4
FY 2007-1
FY 2007-2
FY 2007-3
DAY-1
Beam
MW Drift Chamber
Segmented Scintillation Counters
Beam Optics Calculation
Target Fabrication
Electronics/Gas System/Cables
DAQ
Beam Test Run
Preparation Status and Schedule (slightly changed due to budget situation)
Beam opticsBeam property measurement
1st RIBF PAC
Study of pionic atoms has been yielding fruitful results on the -nucleus s-wave interaction, with interesting implications for the study of chiral restoration in a nuclear medium.
Theoretical evaluation of expected cross section is reliable and is ongoing. (Nara Women's Univ. theory group)
RIBF is the most suitable facility to proceed the study and to perform the systematic spectroscopy. Systematic study is expected to lead to smaller ambiguities in determination of the strong interaction and nuclear matter distribution.
Preparation is now in progress.
Summary
1st RIBF PAC
Human ResourcesRIKEN (Iwasaki-lab) + Tokyo Tech. K. Itahashi, M. Iwasaki, H. Ohnishi, S. Okada, H. Outa, M. Sato, T. Suzuki, T.Yamazaki (Detectors + Electronics + Gas handling) RIKEN (Accelerator) M. Wakasugi, Y. Yano, (Collinear Laser Spectroscopy)GSI (FRS-group) H. Geissel, C. Nociforo, H. Weick (Beam Optics Calculation and Test)University of Tokyo R.S. Hayano, S. Itoh, N. Ono, H. Tatsuno, (Physics + Detectors)Nara Women’s University S. Hirenzaki, R. Kimura, J. YamagataStefan Meyer Institute P. Kienle, K. Suzuki (Target + Physics)Stockholm University P.E. Tegner, K. Lindberg, I. Zartova (Detectors + Electronics + Gas handling)
1st RIBF PAC
Spare
1st RIBF PAC
Readout Electronics + DAQ
MWDC: 8 planes x 48 wires x 2 sets = 768 ch (TDC) 16ch PreAmp + Amp = newly designed by KEK ⇒ fed to VME 64ch TDC (AMT-KEK)
Four step calibration of incident energy in 100 keV precision
Step 0. Set BigRIPS to primary deuteron beam rigidityStep 1. Measure 12C3+ beam velocity by Collinear laser spectroscopy.Step 2. Calibrate BigRIPS by measuring 12C3+ beam position at focus. Step 3. Keep BigRIPS and measure deuteron beam position at focus.