1. g-factor measurement at RISING: The case of 127 Sn Liliya Atanasova University of Sofia

2. MOTIVATION g-factors  reveal information about the nuclear single particle structure: wave function, spin, magnetic dipole operator, …  unique probe to study changes in nuclear shell structure far from stability spin-alignment - in relativistic fission - for projectile fragmentation beams with Z>30  never experimentally proven !  neutron rich nuclei become accessible for moments studies

3. B J Fragment beam METHODOLOGY  L = -g  N B/h Measure Larmor precesion and decay I(t) time 2L2L Time Differential Perturbed Angular Distribution  det 1 det 2 t=0 time Field UP Field DOWN 2A 2 B 2 relative phases depend on g-factor

4. EXPERIMENTAL SET-UP magnet + 8 RISING detectors (top view) Pb-wall + collimator with 7.5 cm to avoid beam scattering Spin-aligned secondary beam selected (S2 slits + position selection in SC21) SC41 SC41 gives t=0 signal for  -decay time measurement SC42 validates the event SC42 Implantation: plexi degrader + 2 mm Cu (annealed) SC43 is a veto (reject non-stopped particle events)

5. g-RISING setup MW1 MW2 music SC43 veto Al degrader SC41 start slits Pb-wall BEAM 4 clusters with BGO anticompton shields and short collimators 4 clusters with the former RISING shields Electronics: VXI and DGF Stopper: 15mm plexiglas + 2 mm Cu

6. 136 Xe fragmentation at 600 Mev/u Sn Spin-alignment and g-factors of isomers in 127,128 Sn from fragmentation of a 136 Xe beam. Dec. 2005 Beam: – 136 Xe at 600 MeV/u Target: 9 Be Thickness: 1023 mg/cm 2 Implantation in thick stopper: 15mm plexiglas + 2 mm Cu (cubic lattice structure, without electric field gradients)

7. Isomers produced in the experiment Z A/Q 128 FIRST RESULTS

8. Pinston et al. PRC61 (2000) 4.5(3)  s 128 Sn 127 Sn FIRST RESULTS

9. 79657721321 Field down Field upStatistics 128Sn 630957201243 34379320561095 3042728571715 Field downField upStatistics 127Sn 128 Sn(8 +  7 - ) 127 Sn 321 128 Sn 127 Sn 128 From S. Lakshmi Counts

10. Analysis is in progress

11. 1. K.U. Leuven, Belgium: N. Vermeulen, G. Neyens, S. Mallion, M. De Rydt, K. Turzó 2. University of Sofia, Bulgaria: A. Blazhev, R. Lozeva (now Leuven), P. Detistov, L. Atanasova 3. ILL Grenoble, France: G. Simpson 4. CEA, Bruyères le Chatel, France: J.M. Daugas, O. Perru 5. ISKP Bonn, Germany: H. Hübel, S Chmel 6. GSI-Darmstadt, Germany: F. Becker, P. Bednarczyk, L. Caceres, P. Doornenbal, J. Gerl, H. Grawe, M. Górska, I. Kojuharov, N. Kurz, W. Prokopowicz, T. Saitoh, H. Schaffner, H.J. Wollersheim 7. IKP Koeln, Germany: J. Jolie, G. Illie 8. IKHP Rossendorf, Germany: R. Schwengner 9. ATOMKI, Debrecen, Hungary: A. Krasznahorkay 10. The Weizmann Institute, Israel: S. Chamoli, M. Hass, B.S. Nara Singh, Laksmi 11. University of Camerino, Italy: D. Balabanski, G. Lo Bianco, K. Galdnishki, A. Saltarelli, C. Petrache 12. University of Milano, Italy: G. Benzoni, N. Blasi, A. Bracco, F. Camera, B. Million, S. Leoni, O. Wieland 13. IFJ-PAN Krakow, Poland: J. Grébosz, M. Kmiecik, A. Maj, K. Mazurek, W. Méczyński, S. Myalsky, J. Styczen, M. Zieblinski 14. Jaggielonian University, Krakow, Poland: R. Kulessa; 15. Warsaw University, Poland: M. Pfűtzner, A. Korgul 16. NIPNE, Bucharest, Romania: M. Ionescu-Bujor 17. Universidad Autonoma de Madrid, Spain: A. Jungclaus, 18. Univerity of Lund, Sweden: C. Fahlander, R. Hoishen, D. Rudolf 19. ISOLDE-CERN, Switzerland: G. Georgiev 20. University of Surrey, UK: Zs. Podolyàk, P.Regan, J. Walker, PD Paddy, PD Zsolt THE g-RISING COLLABORATION