非对称核物质中同位旋对称势的动量和密度依赖性  

Momentum and Density Dependence of Isospin Symmetry Potential in Asymmetric Nuclear Matter

作　　者：左维[1] 陈继延[2] 李宝安 罗培燕[1] Lombardo U 

机构地区：[1]中国科学院近代物理研究所 [2]兰州大学物理学院 [3]INFN-LNS,44 Via S.Sofia,I-95123 Catania,Italy

出　　处：《高能物理与核物理》2005年第9期881-885,共5页High Energy Physics and Nuclear Physics

基　　金：中国科学院知识创新工程重要方向性项目(KJCX2-SW-N02)国家重点基础研究发展规划项目(G2000077400)国家科技部重大前期研究专项基金(2002CCB00200)国家自然科学基金(10235030;10175082)国家自然科学基金委创新群体项目资助~~

摘　　要：在Brueckner-Hartree-Fock理论框架内,研究了同位旋非对称核物质中质子和中子单粒子势的动量相关性及其随同位旋非对称度的变化,在此基础上计算了同位旋对称势,并讨论了三体核力的影响.结果表明同位旋对称势对于同位旋非对称度的依赖性很弱,但对于动量和密度均有较强的依赖性.当密度固定时,同位旋对称势随动量增加而减小.尽管三体核力对于质子和中子单粒子势的动量相关性有较大影响,但对同位旋对称势的影响很小.还与目前重离子碰撞输运理论模型中所使用的各种参数化的唯象对称势进行了比较.Within the isospin dependent Brueckner-Hartree-Fock framework, the proton and neutron single particle potentials in isospin asymmetric nuclear matter as well as their isospin denpendence have been investigated. The symmetry potential is extracted from the proton and neutron single nucleon potentials. The symmetry potential turns out to depend strongly on both momentum and density, while it is almost independent of the isospin asymmetry. The density and momentum dependence of the predicted symmetry potential has been compared with the phenomenological parameterizations adopted in the BUU simulations of the heavy ion collisions induced by neutron-rich nuclei. It is found that the microscopic symmetry potential shows a completely different momentum and density dependence from the phenomenological ones and thus the present results are useful for putting a strict constraint on the phenomenological models for the symmetry potential.

关 键 词：Brueckner-Hartree-Fock方法 同位旋对称势 动量和密度相关性 三体核力 重离子碰撞 密度依赖性 非对称核物质 动量相关 Brueckner-Hartree-Fock理论 同位旋 

分 类 号：O571.2[理学—粒子物理与原子核物理]