Microscopic description of Gamow-Teller transitions in middle pf--shell nuclei by a realistic shell model calculation
Microscopic description of Gamow-Teller transitions in middle pf--shell nuclei by a realistic shell model calculation
复制标题
通过真实壳模型计算对中pf-壳核中伽莫夫-泰勒转变的微观描述
DOI：
10.1088/0954-3899/22/9/008
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发表时间：
1996
期刊：
影响因子：
--
通讯作者：
T. Sebe
中科院分区：
文献类型：
--
作者：
H. Nakada;T. Sebe
利用Towner的微观参数，通过大规模的真实壳模型计算，研究了N=28\sim 30$原子核中的GT跃迁。$B({\rm gt})$值以合理的精度复制到低位终态。用这组波函数和算符研究了关于GT跃迁的几个总体性质。虽然计算的总GT^-$强度与实测值没有明显的不一致，但计算的总GT^+$强度比电荷交换实验得到的稍大一些。关于池田求和规则，$S与$(N-Z)$的比例保持在一个极好的近似值，猝灭因子为0.68。对于可能的同位旋分量中的相对GT$^-$强度，最低的同位旋分量聚集的分数比同位旋耦合的平方CG系数所预期的要大。事实证明，这些相对强度对模型空间的大小不敏感。对于每个同位旋分量，讨论了相加的$B({\rm gt})$值的系统学。
GT transitions in $N=28\sim 30$ nuclei are studied in terms of a large-scale realistic shell-model calculation, by using Towner's microscopic parameters. $B({\rm GT})$ values to low-lying final states are reproduced with a reasonable accuracy. Several gross properties with respect to the GT transitions are investigated with this set of the wavefunctions and the operator. While the calculated total GT$^-$ strengths show no apparent disagreement with the measured ones, the calculated total GT$^+$ strengths are somewhat larger than those obtained from charge-exchange experiments. Concerning the Ikeda sum-rule, the proportionality of $S_{\rm GT}$ to $(N-Z)$ persists to an excellent approximation, with a quenching factor of 0.68. For the relative GT$^-$ strengths among possible isospin components, the lowest isospin component gathers greater fraction than expected by the squared CG coefficients of the isospin coupling. It turns out that these relative strengths are insensitive to the size of model space. Systematics of the summed $B({\rm GT})$ values are discussed for each isospin component.