Michel Hass (Weizmann Institute of Science, Israel), Measurements of static electromagnetic moments in fragmentation reactions - experiments at GANIL and at GSI

Thursday 10 May 2007, 10:00 → 11:00 Europe/Bucharest

Fragmentation reactions at intermediate and relativistic energies are one of the best means to produce nuclei-far-from stability and hence study nuclear structure at extreme isospin. The deter- mination of Electromagnetic moments has always played a crucial role in elucidation and verifying nuclear structure models and, hence, it is of extreme importance in this context to extend the exper-imental tools for measurement of static electromagnetic moments, that have been developed before for, e.g., fusion-evaporation reactions, to this domain as well. We present results from GANIL, at intermediate energies and, from GSI, at relativistic energies. At GANIL, we report on the first quadrupole moment measurement of an isomeric level populated by a projectile fragmentation reaction using the Time Dependent Perturbed Angular Distribution (TDPAD) technique. The 61Fe(9/2+) (E = 861 keV and T1=2= 239(5) ns) isomeric state was produced and spin-aligned by the intermediate energy fragmentation of a 64Ni beam at the GANIL facility and the quadrupole interaction frequency was measured in a Cd single crystal. The deduced quadrupole moment jQj = 41(6) efm2 is compared with large scale shell model calculations. The present measurement paves the way for future determinations of isomeric quadrupole moments in more exotic nuclei. At GSI, we report on an experiment to measure magnetic moments of Sn isotopes at the RISING Ge-detector array, using the fragmentation of a relativistic 136Xe beam. We present preliminary results for 127;128Sn. PACS numbers: PACS 21.10.Ky, 23.20.En, 25.70.Mn,21.60.-n