核势和核子有效质量的同位旋相关性(英文)

Isospin-Dependence of Nucleon Potential and Effective Mass in Relativistic Approach

在Dirac Brueckner Hartree-Fock(DBHF)理论框架下研究了核子光学势和核子有效质量的同位旋相关性．非对称核物质的计算采用了DBHF的核子自能的Dirac结构的新的分解方法,核子自能的实部是用G矩阵在Hartree-Fock近似下计算得到,而虚部从极化图得到．用核子的薛定谔等价势可以得到核子矢量有效质量．研究表明考虑了核势的能量相关性在丰中子核物质情况下核子矢量有效质量比质子的大．

The isospin-dependence of nucleon optical potentials and the nucleon effective mass is studied in the framework of the Dirac Brueckner Hartree-Fock （DBHF） approach. A new decomposition of the Dirac structure of the nuclear self-energy in the DBHF is extended to asymmetric nuclear matter calculations. The real part of the nucleon self-energy in asymmetric nuclear matter is calculated with the G-matrix in the Hartree-Fock approach, while the imaginary part is obtained from the polarization diagram. The nucleon vector effective mass is derived from the Schroedinger equivalent potentials. It is found that the neutron vector effective mass is larger than that of proton in the neutron-rich nuclear matter once the energy dependence of the nucleon potentials is considered.