YRAST ISOMERS, MULTI-QUASI-PARTICLE STATES AND BLOCKING IN TA-176 AND TA-177

被引:25
作者
DASGUPTA, M [1 ]
WALKER, PM [1 ]
DRACOULIS, GD [1 ]
BYRNE, AP [1 ]
REGAN, PH [1 ]
KIBEDI, T [1 ]
LANE, GJ [1 ]
YEUNG, KC [1 ]
机构
[1] UNIV SURREY,DEPT PHYS,GUILDFORD GU2 5XH,SURREY,ENGLAND
关键词
D O I
10.1016/0370-2693(94)90421-9
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
K(pi) = 20- and 49/2- yrast isomers have been discovered in Ta-176 and Ta-177, with meanlives of 1.4 ms and 0.19 ms, respectively. The long meanlives arise from substantial K-hindrance in the Ta-176 case but from spin-trapping in the Ta-177 case. Quasiparticle calculations, which treat the Fermi and pairing energies self-consistently, reproduce the excitation energies of these isomers and the other multi-quasiparticle high-K states observed. Due to blocking, pairing is significantly reduced in the 3-quasiparticle states, the extent depending on the specific configurations. It is completely quenched for both protons and neutrons in the highest seniority states. Yrast traps of even higher spin are predicted to exist in Ta-176 and Ta-177.
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页码:16 / 21
页数:6
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