非对称核物质中质子和中子的~1S_0态超流性

Proton and neutron ~1S_0 superfluidity in asymmetric nuclear matter

利用Brueckner-Hartree-Fock和BCS理论方法,计算了非对称核物质中处于1S0态的质子和中子的对关联能隙,着重研究和讨论了能隙的同位旋依赖性和三体核力的影响.结果表明:随核物质的同位旋非对称度增大,中子1S0态超流相存在的密度范围逐渐缩小而且对关联能隙峰值稍有升高;质子1S0态超流相存在的密度范围迅速扩大而且对关联能隙峰值显著降低.三体核力对非对称核物质中1S0态中子超流性及其同位旋依赖性的影响相对较小,但对1S0态质子超流性具有重要影响,而且其效应随核子数密度增大而迅速增强.三体核力的主要作用是强烈地抑制了具有高非对称度的核物质中高密度区域的1S0态质子超流性,导致质子超流相存在的密度范围显著缩小.

The proton and neutron 1SO pairing gaps and their isospin dependence in isospin asymmetric nuclear matter have been studied by the isospin dependent Brueckner-Hartree-Fock approach and the BCS theory. We have focused on investigating and discussing the effect of three-body force. The calculated results indicate that as the isospin asymmetry increases, the density range of the 1 So neutron superfluidity is narrowed slightly and the maximum value of the neutron pairing gap increases, while the density domain for the proton superfluidity enlarges rapidly and the peak value of the proton gap decreases remarkably. The three-body force turns out to affect only weakly the neutron 1 So superfluidity and its isospin dependence, i. e., it leads to a small reduction of the neutron 1So paring gap. However, the three-body force not only reduces largely the strength of the proton 1So gaps at high densities in highly asymmetric nuclear matter but also suppresses strongly the density domain for the proton 1So superfluidity phase.