用中子晕弹核探寻同位旋非对称核物质状态方程  

Probing the Equation of State for Ansymmetrical Isospin Nuclear Matter by Means of Halo-neutron Projectile

作　　者：刘建业[1] 

机构地区：[1]中国科学院近代物理研究所,甘肃兰州730000

出　　处：《原子核物理评论》2008年第1期8-14,共7页Nuclear Physics Review

基　　金：国家重点基础研究发展计划(G2000077400);国家自然科学基金重点项目(10435080);国家自然科学基金面上项目(10447006;10575075);中国科学院知识创新工程重要方向项目(KJCX2-SW-No2)~~

摘　　要：总结和评述了用中子晕弹核探寻同位旋非对称核物质状态方程。在具有同位旋和动量依赖的同位旋相关量子分子动力学框架内,采用对比中子晕弹核和相等质量稳定弹核在完全相同入射道条件下物理观测量的差别,来突出中子晕核明显的同位旋效应和加强物理观测量对于同位旋的灵敏性,从而提取核物质状态方程。例如,与稳定弹核碰撞系统相比,中子晕弹核明显提高了发射核子的中子-质子比和增加了它对于对称势的灵敏性,这两点特征非常有利于提取对称势。同样,由于中子晕弹核碰撞系统在低能区(E<60MeV)由于内部松散结构减弱了核子碰撞力度和动量耗散,与稳定核碰撞系统相比,明显提高了原子核阻止;而在高能区由于两体碰撞同位旋效应的增加,从而明显提高了原子核阻止。利用这些特征可以提取核子-核子碰撞截面的介质效应和同位旋依赖性。Based on the isospin and momentum dependent quantum molecular dynamics, we use the comparison for the differences between observables in the reactions induced by the halo-neutron projectile and stable projectile with the same mass under complete same incident channel condition to protrude the isospin effect of halo-neutron projectile and strengthen the sensitivity of observable on the isospin for extracting the information for the equation of state. For example, the halo-neutron projectile increases the emitted neutron-proton ratio and then enhances its sensitivity on the symmetrical potential. Two points above are more favorable than the normal neutron-rich and neutron-poor projectiles for extracting the symmetry potential. We also found that the neutron-halo projectile induces the decrease of nuclear stopping in lower beam energy region and the increase in higher beam energy region, compared to corresponding same mass stable projectile under the same incident channel condition, so that we can use these properties to extract the information for the medium effect and isospin effect of in-medium nucleon-nucleon cross section.

关 键 词：中子晕弹核 对称势 核子-核子碰撞截面 

分 类 号：O571.251[理学—粒子物理与原子核物理] O571.4[理学—物理]