核质量公式壳层修正项的比较

本文对核质量公式中的壳层修正项进行比较。我们选择了目前常用的四种核质量公式和三种壳层修正项互相配合,计算了1270个核素的质量,并讨论了计算结果,指出了与实验符合最好的核质量公式和壳修正项的形式。这些计算可作为进一步改进壳修正项的参考。

A COMPARISON OF SHELL CORRECTION TERMS IN THE NUCLEAR MASS FORMULAS

In this paper, We compare various shell correction terms in the nuclear mass formulas. We add one of three types of shell correction term (Wing-Fong′s, Seeger′sand Myers′term) to each of the four mass formulas (Tseng-Cheng-Yang, Danos-Gillet, Myers-Swiatecki and Weizsacker formula) respectively. Thus, We can get 12 different combination, or 12 mass formulas. These are used to calcula-te the mass of 1270 nuclides (A≥16) respectively. The results show that Wing-Fong′s correction term is best, and Myers one is worst of these 12 mass formulas, Tseng-Cheng-yangformulas plus Wing-Fong correction term have least root-mean-spuare deviation (1.54 Mev). If we omit the light nuclid (A<50), then the root-mean-square deviation decrease to 1.24 MeV. In the above calculations, We have not consider the deformation of nuclei and neutron-proton interaction in light nuclei and well-deformed nuclei. We believe that the root-mean-square-deviation will decrease if one takes these effect into account and readjusts the parameters in the mass formulas.