Precision experiments of stored exotic nuclei mass & lifetime - PowerPoint PPT Presentation

Precision experiments of stored exotic nuclei mass & lifetime measurements at the storage rings Taka Yamaguchi (Saitama, Japan) For FRS-ESR/ILIMA collaboration, For Rare-RI Ring collaboration 1. Highlights of the ESR experiments  Time-resolved Schottky mass spectrometry (SMS)  Isochronous mass spectrometry (IMS) 2. Future facilities ILIMA collaboration (FAIR) • Upgrade of present activities at ESR • Rare-RI Ring collaboration (RIBF) • Concept, principle, R&D  2010 年 9 月 26 日日曜日 1

FRS-ESR Facility at GSI All elements: H-U Energy: up to 1GeV/u Monoisotopic fragment beams stored in the ESR 2010 年 9 月 26 日日曜日 2

Schottky Mass Spectrometry, Isochronous Mass Spectrometry SMS IMS Stochastic Isochronous + optics Electron cooling 2010 年 9 月 26 日日曜日 3

Frequency Spectrum, an example Y. Litvinov Yu.A. Litvinov 2010 年 9 月 26 日日曜日 4

Sensitivity to single ions 2010 年 9 月 26 日日曜日 5

High-accuracy Mass Measurements Mass Evaluation of Close-lying Frequency Peaks δ m/m=4.3x10 -8 2010 年 9 月 26 日日曜日 6

Mass Surface measured with the SMS Masses of more than 1000 Nuclides were measured Mass accuracy: 1.5 ·10 -7 Mass resolving power: 2 ·10 6 Results: 320 new masses In addition more than 300 improved mass values Yu.A. Litvinov et al., Nucl. Phys. A756 (2005) 3. 2010 年 9 月 26 日日曜日 7

Recent Highlights with the SMS •Proton-neutron interaction strength around N=126 •L. Chen et al., PRL102(2009)122503. •New isomers •Excitation energies, lifetimes •B. Sun et al., PLB688(2010)294. •M.W. Reed et al., PRL accepted. •New isotopes discovered at ESR •Mass simultaneously measured •L. Chen et al. PLB691(2010)234. 2010 年 9 月 26 日日曜日 8

Time-resolved Schottky Mass Spectrometry Electron cooling SMS amplification Schottky summation Pick-ups FFT 0 f ~ 2 MHz 0 Continuous digitizing and storage of raw data Stored ion beam 0 Time after injection / s Noise power density / arb. u. + β -decay - nuclear e -capture 150 300 450 + β -decay 600 153.9 8.2 8.3 8.4 8.5 154.0 154.1 154.2 8.0 8.1 Frequency / kHz 2010 年 9 月 26 日日曜日 9

Nuclear Decays observed in the Ring Yu.A. Litvinov 2010 年 9 月 26 日日曜日 10

Lifetime Measurements via SMS Exotic decay modes of highly-charged ions Bound-state beta decay of 207 Tl 81+ T. Ohtsubo at al., PRL95(2005)052501. 2010 年 9 月 26 日日曜日 11

Recent Highlights with the SMS Fully ionized •Electron capture decays of HCI Enhancement of EC rates of hydrogen-like ions •Y. Litvinov et al., PRL99(2007)262501. •N. Winckler et al., PLB679(2009)36. •Non-exponential EC decays •Y. Litvinov et al., PLB664(2008)162. H-like He-like 2010 年 9 月 26 日日曜日 12

Isochronous Mass Spectrometry -> 40GS (TDS6154C) TOF detector MCP C foil MCP Secondary electrons 2010 年 9 月 26 日日曜日 13

Pulses of Stored Ions raw data Look for repeating peaks J. Stadlmann 2010 年 9 月 26 日日曜日 14

Time-of-Flight Spectrum Fragments from fission of 238 U Δ (m/q)/(m/q) ~ 13% Identification by m/q ratio B. Sun, R. Knoebel, S. Nakajima 2010 年 9 月 26 日日曜日 15

Isochronicity - improvement - B ρ -tagging method Revolution Time Δ T/T [10 -5 ] Δ B ρ /B ρ [10 -3 ] H. Geissel 2010 年 9 月 26 日日曜日 16

Experiment 2006 Goal: to measure the masses of n-rich fission products at the r-process path B ρ -tagging was applied Primary beam: 238 U Intensity: ~ 3 · 10 9 /spill E SIS : 411MeV/u Target : 1g/cm 2 9 Be B. Sun et al. Nucl. Phys. A 812 (2008) 1 2010 年 9 月 26 日日曜日 17

FAIR - Future Facility - SIS 100/300 Future facility SIS 18 ESR GSI today Super -FRS RESR from FAIR web site CR NESR 2010 年 9 月 26 日日曜日 18

Mass & Lifetime Measurements at CR/NESR ILIMA collaboration B ρ -tagging IMS SMS R&D • Ion optics • Resonant Schottky probe • TOF Detectors • Multiple pickup • DAQ, analysis softwares • Decay particle detectors 2010 年 9 月 26 日日曜日 19

ILIMA collaboration at FAIR K. Takahashi (Bruxelles) E. Badura, K. Beckert, F. Bosch, D. Boutin, A. Dolinski, B. Franzke, H. Geissel, F. Herfurth, J. Hoffmann, H.-J. Kluge, C. Kozhuharov, S.A. Litvinov, G. Muenzenberg, I. Nesmiyan, F. Nickel, F. Nolden, W. Otto, W. Quint, C. Scheidenberger M. Steck, Th. Stoehlker, S. Typel, H. Weick, M. Winkler (GSI) M. Hausmann, M. Matos, H. Schatz (MSU) T. Faestermann, P. Kienle, L. Maier, P. Ring, D. Vretenar (Muenchen) D.M. Seliverstov, G.K. Vorobjev (St. Petersburg) L. Chen, Z. Di, T. Dickel, A. Fettouhi, R.K. Knoebel, M. Petrick, W.R. Plass (Giessen) Z. Podolyak, P.M. Walker (Surrey) stable nuclei Th. Buervenich (Frankfurt) R. Mao, Z. Sun, G. Xiao (Lanzhou) nuclides with known masses G.Audi et al., Nucl. Phys. A729 (2003) 3 D. Madland, P. Moeller, D. Vieira (Los Alamos) to be measured with SUPER-FRS-CR-RESR-NESR K.-L. Kratz, B. Pfeiffer (Mainz) Conceptual Design Report, GSI 2001 K. Blaum (Max-Planck) observed nuclei 82 D. Cullen (Manchester) T. Ohtsubo (Niigata) G. Audi, D. Lunney (Orsay) r-process T. Yamaguchi (Saitama) path 126 G.A. Lalazissis (Thessaloniki) Z. Patyk (Warsaw) 50 82 28 Isomeric Beams, Lifetimes and Masses 50 20 Spokesperson: P.M. Walker 8 28 20 8 2010 年 9 月 26 日日曜日 20

Measure the masses in the r-process Rare-RI Ring project at RIBF T. Fujinawa, N. Fukunishi, A. Goto, H. Sakurai, M. Wakasugi, Y. Yamaguchi, Y. Yano RIKEN Nishina Center I. Arai, T. Moriguchi, D. Nagae, A. Ozawa, H. Suzuki Univ. of Tsukuba 82 T. Suzuki, T. Yamaguchi, Saitama Univ. proton drip-line T. Kikuchi A/Z =3 line Nagaoka Univ.of Tech 50 126 neutron drip-line 28 82 20 50 r-process path 8 stable nuclei 28 20 Z 2 16 unstable nuclei 8 (with known masses) 2 N A ME2003 2010 年 9 月 26 日日曜日 21

Conceptual Design Individual injection method Trigger signal B SRC PID A Isochronous F3 100MeV/u Storage Kicker TOF ~ 1ms Ring BigRIPS PID C Long injection beam line Accuracy of requirement β measurement TOF δ T / T measurement < 10 -6 Δ m/m ~ 10 -6 β measurement < 10 -4 δβ / β Isochronous magnetic field < 10 -6 δ B 0 / B 0 2010 年 9 月 26 日日曜日 22

Layout of Rare RI Ring Mass measurement = BigRIPS + SHARAQ line + Storage Ring RI Beam Factory Rare RI Ring BigRIPS 2010 年 9 月 26 日日曜日 23

R&D ongoing TARNII-D 、 24 • Optics calculations TARNII-Q 、 20 • Injection beam line KEK-PS-Q 、 23 • Injection/ejection scheme • Storage Ring o Higher-order/realistic calculations • Kicker, Septum • Improved controller: response time ~450ns • Specifications o Test of model kicker • TOF counters • Test of µ m-thick plastic scintillator • Test of hybrid photo detector • Test of MCP detector • High-precision NMR probe • Precision ~ 10 -7 2010 年 9 月 26 日日曜日 24

CSR - Cooler Storage Ring at Lanzhou - Major parameters of CSRe Max. Energy: 400MeV/u (U 90+ ) Intensity: 10 9 B ρ (max): 8.40 Tm First IMS at CSRe : 2009 Sep.-Oct. 59 Zn, 61 Ga, 63 Ge, 65 As, 67 Se, 71 Kr 2010 年 9 月 26 日日曜日 25

Concluding Remarks - Storage Ring Mass Spectrometry at ESR is ongoing. - Large areas of unknown mass surface - Exotic decay modes of highly-charged ions - The future international collaboration ILIMA at FAIR is promising for the continuation and upgrade of the current ESR activities. - Rare-RI Ring project will work in a complementary style. - The storage ring in China is a candidate to extend our activities. 2010 年 9 月 26 日日曜日 26