非对称核物质中的中子-质子对关联  

Neutron-proton pair correlations in asymmetric nuclear matter

作　　者：尚新乐[1] 

机构地区：[1]中国科学院近代物理研究所

出　　处：《中国科学：物理学、力学、天文学》2016年第1期210-218,共9页Scientia Sinica Physica,Mechanica & Astronomica

基　　金：国家自然科学基金资助项目(批准号:11347151;11435014;11175219)

摘　　要：n-p对关联的准确知识对于核物理及天体物理的相关研究非常重要,然而,当前对核物质超流性的准确认识仍有许多问题.基于此,我们总结了影响非对称核物质n-p对关联的两个因素,能隙的方向依赖性以及n-n,p-p,n-p三种Cooper对的耦合.能隙的方向依赖性可以在一定程度上缓解非对称度对n-p对关联的抑制.同时,当考虑能隙的方向依赖性时,FFLO态的Cooper对动量在空间的取向不再是简并的,会劈裂成两种超流态,并且会在较大的非对称度范围存在.另一方面,n-n,p-p,n-p三种Cooper对的共存在非对称核物质中是可以发生的,并且当n-p对相互作用远强于n-n对相互作用时,n-n对,p-p对的存在也会缓解非对称度对n-p对的抑制.Neutron-proton pair correlations are potentially important in related research of nuclear physics and astrophysics. However, there are still many problems to understand the superfluidity of the nuclear matter accurately. Accordingly, we summarize the influences of the angle dependence of the pairing gap and the coupling of the neutron-neutron, neutron-proton, proton- proton Cooper pairs on the n-p pair correlations in asymmetric nuclear matter. The angle dependence of the pairing gap can reduce the suppression by the isospin asymmetry. Meanwhile, the FFLO state is nondegenerate for the orientations of the Cooper pair momentum by considering the angle dependence of the pairing gap. The superconducting state then splits into two branches. And the critical isospin asymmetry αc, where the superfluid vanishes, is enhanced largely by considering the Cooper pair momentum with the angle dependence of the pairing gap. Moreover, the coexistence of the neutron-neutron, neutron-proton, proton-proton Cooper pairs in the asymmetric nuclear matter is possible. If the pairing interaction of n-p pair correlations is much stronger than that of n-n pair correlations, the existences of n-n and p-p pair correlations can also reduce the the suppression by the isospin asymmetry.

关 键 词：非对称核物质 超流性 BCS理论 

分 类 号：O571.2[理学—粒子物理与原子核物理]