^(190,192)Pb原子核的超形变带的带外衰变（英文）  

Decay Out of Superdeformed Bands in ^(190,192)Pb

作　　者：顾建中[1] 彭帮保 李振宇[3] 于国梁[4] 

机构地区：[1]中国原子能科学研究院,北京102413 [2]哈尔滨工程大学核安全与仿真技术国家实验室,哈尔滨150001 [3]贵州师范学院物理与电子学院,贵阳550018 [4]华北电力大学数理系,河北保定071003

出　　处：《原子核物理评论》2017年第1期57-61,共5页Nuclear Physics Review

基　　金：National Natural Science Foundation of China(11275271);Foundation for Innovative Research Groups of the National Natural Science Foundation of China(11321064)~~

摘　　要：将基于组合方法的角动量投影的位能曲面群用于研究铅同位素原子核^(190,192)Pb的超形变转动带。位能曲面群计算中采用了Gogny D1S以及Skyrme Sk P SLy4三种相互作用。如用Gogny D1S相互作用,^(190)Pb原子核没有明显的超形变转动带,而^(192)Pb原子核有非常显著的超形变转动带。用W.K.B.方法计算了^(192)Pb原子核的超形变带穿透宽度。该穿透宽度很大与用GW模型(Nucl.Phys.A 660(1999)197)分析实验数据给出的结果相近。在Gogny D1S相互作用情形下,就角动量投影对位能曲面群的影响作了讨论,发现角动量投影压低了分隔超形变转动带与正常形变转动带之间的位垒。还用Skyrme Sk P和SLy4相互作用计算了角动量投影的位能曲面群,发现位垒明显高于Gogny D1S相互作用给出的位垒。在Skyrme相互作用情形下,^(192)Pb原子核的超形变带穿透宽度明显小于Gogny相互作用给出的宽度,但是较SB方法 (Phys.Rev.C,60(1999)051305)分析实验数据得到的结果高出几个数量级。于是,对SB方法提出了质疑,因为它给出了极其微小的传播宽度。The combined method is applied to calculate the angular momentum projected potential energy surfaces（AMPPES） of ^190,192Pb. The Supper-deformed（SD） rotational bands of the two nuclei are studied with the AMPPES computed with the Gogny D1 S and Skyrme Sk P and SLy4 interactions.It is found that there is no pronounced SD band in ^190Pb in the case of the Gogny interaction, which is consistent with the experimental observation. A well developed SD band with the Gogny interaction is found in ^（192）Pb. The tunneling width of ^192Pb is comparable to that given by the GW approach（Nucl. Phys. A 660（1999）197） and orders of magnitude larger than that given by the SB approach（Phys. Rev. C 60（1999） 051305）. The influence of the angular momentum projection on the potential energy surfaces is examined in the case of the Gogny interaction for ^190,192Pb. It is shown that the angular momentum projection suppresses the barrier separating the SD and ND rotational bands. Higher barriers of the AMPPESs for the two nuclei computed with the Skyrme Sk P and SLy4 interactions are obtained compared with those given by the Gogny force. The tunneling width of ^192Pb is also big for the Skyrme interactions. We put the SB approach into question which gives only an extremely small spreading width.

关 键 词：组合方法 带外衰变 角动量投影的位能面群 

分 类 号：O571.6[理学—粒子物理与原子核物理]