New sub-µs isomers have been observed in the neutron-rich Sn isotopes. Sn-125,Sn-127,Sn-129 nuclei have been produced in a relativistic fission reaction of U-238 on a Be-9 target at 750 A.MeV and by the fragmentation of Xe-136 at 600 A.MeV populating high-spin yrast states. In addition to the already known µs isomers, three new ones with sub-µs half-lives have been observed. These yrast isomers are the high-spin members of the nu(d(3/2)(-1)h(11/2)(-2)) and nu h(11/2)(-n), seniority v = 3 multiplets leading to isomeric (23/2(+)) and (27/2(-)) states, respectively. Added to the already known 19/2(+) µs isomers in this region the current work completes the systematic information of neutron-hole excitations toward the filling of the last h(11/2) orbital at N = 82. The results are discussed in the framework of state-of-the-art shell-model calculations using realistic interactions.
|Titolo:||New sub-µs isomers in Sn-125,Sn-127,Sn-129 and isomer systematics of Sn124-130|
|Parole Chiave:||heavy-ion collision ; gamma-ray ; transition-probabilities ; yrast isomers ; energy-levels ; beta-decay ; isotopes ; nuclei ; GSI ; detectors|
|Settore Scientifico Disciplinare:||Settore FIS/01 - Fisica Sperimentale|
Settore FIS/04 - Fisica Nucleare e Subnucleare
|Data di pubblicazione:||giu-2008|
|Digital Object Identifier (DOI):||10.1103/PhysRevC.77.064313|
|Appare nelle tipologie:||01 - Articolo su periodico|