Electric quadrupole moment of17Band anomalousE2effective charges for neutron-rich nuclei
Electric quadrupole moment of17Band anomalousE2effective charges for neutron-rich nuclei
复制标题
富中子核17带反常E2有效电荷的电四极矩
DOI：
10.1103/physrevc.67.064308
复制
发表时间：
2003
影响因子：
3.1
通讯作者：
S. Teughels
中科院分区：
文献类型：
--
作者：
H. Ogawa;K. Asahi;K. Sakai;T. Suzuki;H. Izumi;H. Miyoshi;M. Nagakura;K. Yogo;A. Goto;T. Suga;T. Honda;H. Ueno;Y. Watanabe;K. Yoneda;A. Yoshimi;N. Fukuda;Y. Kobayashi;A. Yoshida;T. Kubo;M. Ishihara;N. Imai;N. Aoi;W. Schmidt;G. Neyens;S. Teughels
用β核磁共振法测定了17B基态的电四极矩Q。由测得的四极耦合常数|e q q/h(17B单位为mg)|=137.4±4.5 kHz，推算出镁单晶阻挡层中17B的Q矩为|q(17B)|=38.6±1.5mb。与前面的15B结果一样，所得到的Q矩与N=8的同位素13B的Q矩非常接近，这与用常有效电荷的常规壳层模型计算结果形成鲜明对比。壳层模型计算结果表明，对于(N−Z)/A较大的同位素，E_2有效电荷显著降低。用玻尔和莫特森预测的依赖于(N-−-Z)/A的E2极化电荷和考虑了松散结合粒子的解耦特性，很好地解释了这一结果。
The electric quadrupole moment Q for the ground state of 17 B was determined by the β-NMR method applied to spin-polarized projectile fragments. From the measured quadrupole coupling constant,| e q Q/h (17 B in Mg)|= 137.4±4.5 kHz, for 17 B in a Mg single crystal stopper the Q moment was deduced as| Q (17 B)|= 38.6±1.5 mb. As was the case in the previous 15 B result, the obtained Q moment is very close to that for the N= 8 isotope 13 B, in sharp contrast to the results of conventional shell-model calculations using constant effective charges. Comparison of the shell-model calculations indicates substantial reduction of the E 2 effective charges for isotopes with large (N− Z)/A ratios. The results were well accounted for in terms of (N− Z)/A dependent E 2 polarization charges as predicted by Bohr and Mottelson and by incorporating the decoupling feature of loosely bound particles.