相对论平均场理论对Se，Kr，Sr和Zr同位素链形状共存的系统研究

在约束形变的相对论平均场理论下，用NL3参数组系统地研究了Se，Kr，Sr和Zr四个同位素链中的偶-偶核，理论计算的基态束缚能和实验值符合得非常好.通过对这些核的位能曲面的分析，发现在此区域内有着丰富的形状共存现象，系统地指出可能存在形状共存现象的原子核，并且进一步指出在这些核的位能曲面上两个能量极小点的能量差.另外通过对位能曲面以及单中子能级的研究，提出在此区域内N＝70可能是一个中子幻数. 关键词： 形状共存 相对论平均场 位能曲面 幻数

Systematic investigation of shape-coexistence in Se,Kr,Sr and Zr isotopes with relativistic mean field theory

The even-even nuclei of Se, Kr, Sr and Zr isotopes are investigated systemically by the constrained relativistic mean field theory with the interactions NL3. The calculated binding energies of ground state for Se, Kr, Sr and Zr isotopes are described fairly well as compared with experiments. By examining the potential energy surfaces obtained by this microscopic approach, it can be found that the shape-coexistence phenomenon is very common in this region. The possible nuclei with shape-coexistence are pointed out systemically and the energy differences between the two minima in the potential energy surfaces for those nuclei are presented as well. In addition, by examining the potential energy surfaces and the microscopic neutron single particle spectra, N=70 are suggested to be a possible neutron magic number in this region.