核物质热力学性质的同位旋和动量相关性  

Effects of Isospin and Momentum-dependent Interactions on Thermal Properties of Nuclear Matter

作　　者：徐骏[1] 陈列文[1,2] 李宝安 马红孺[1] 

机构地区：[1]上海交通大学理论物理研究所,上海200240 [2]兰州重离子加速器国家实验室原子核理论中心,甘肃兰州730000 [3]Department of Physics, Texas A＆M University-Commerce, Commerce, TX 75429, USA

出　　处：《原子核物理评论》2009年第2期93-101,共9页Nuclear Physics Review

基　　金：国家自然科学基金资助项目(10334020,10575071,10675082);教育部新世纪优秀人才计划项目(NCET-05-0392973);上海市青年科技启明星计划项目(06QA14024);国家重点基础研究发展规划项目(973计划项目)(2007CB815004);李宝安的工作由美国国家科学基金(PHY-0652548,PHY-0757839);研究合作奖(7123);美国德得州董事会奖项目资助(003565-0004-2007)~~

摘　　要：利用3个具有不同的同位旋和动量相关性的热力学模型研究了非对称核物质的热力学性质,它们是重离子碰撞中同位旋弥散数据约束下的、同位旋和动量相关的MDI模型,完全动量无关的MID模型,以及同位旋标量动量相关的extended MDYI(eMDYI)模型。主要研究了同位旋非对称热核物质的对称能和系统力、化学不稳定性以及液气相变的温度效应。MDI模型对称能的温度效应来源于动能和势能两部分贡献,而MID和eMDYI模型只有势能部分对对称能的温度效应有贡献。研究结果还表明,力学不稳定性区域、化学不稳定性区域和液气共存区都依赖于模型的同位旋和动量相关性,以及对称能的密度依赖关系。In this article, three models with different isospin and momentum dependence are used to study the thermodynamical properties of asymmetric nuclear matter. They are isospin and momentum-dependent MDI interaction constrained by the isospin diffusion data of heavy ion collision, the momentum-independent MID interaction and the isoscalar momentum-dependent eMDYI interaction. Temperature effects of symmetry energy, mechanical and chemical instability and liquid-gas phase transition are analyzed. It is found that for MDI model the temperature effects of the symmetry energy attribute from both the kinetic and potential energy, while only potential part contributes to the decreasing of the symmetry energy for MID and eMDYI models. We also find that the mechanical instability, chemical instability and liquid-gas phase transition are all sensitive to the isospin and momentum dependence and the density dependence of the symmetry energy.

关 键 词：同位旋 动量相关 对称能 不稳定性 液气相变 

分 类 号：O571.415[理学—粒子物理与原子核物理]