有效液滴模型对超铅区结团放射性的研究

Systematic calculations on cluster radioactivity half-lives of trans-lead nuclei with effective liquid drop model

利用有效液滴模型计算了超铅区结团放射半衰期.在计算Gamow势垒穿透因子时采用了碎块体积不守恒以及有效惯性系数因子,并用有效的核半径常数公式代替原来的经验公式.理论计算得到的结团放射半衰期和实验值符合得很好,其半衰期对数值的均方差只有0.895.理论结果表明,有效液滴模型能充分反映N=126和Z=82的壳效应,并且在奇数结团25Ne,29Mg中出现了明显的奇偶质量摆动现象.另外,理论计算得到的结团半衰期基本符合盖革-努塔尔定律,并基于理论结果得到了一些关于盖革-努塔尔定律的有意义的结论.

The cluster radioactivities of trans-lead nuclei are systematically investigated by using the effective liquid drop description with the varying mass asymmetry shape and effective inertial coefficient. An effective nuclear radius constant formula is used instead of the original empirical formula in calculation. The calculated half-lives are in good agreement with the available experimental data. The root-mean-square deviation between the calculated logarithmic half-lives and the experimental ones is only 0.895. From the plots of the calculated lgT1/2 values versus the neutron （or proton） number of daughter, the shell effect of neutron magic number N =126 （or proton magic number Z =82） can be clearly seen. The odd-even-stagger can be clearly seen in the odd clusters 25Ne, 29Mg. The calculated half-lives conform to the Geiger-Nuttall law. We obtain some important conclusions about the Geiger-Nuttall law from the calculated results.