库仑作用对同位旋分馏过程的影响  

Effect of Coulomb Interaction on Isospin Fractionation Process

作　　者：郭文军[1] 刘建业[1] 邢永忠[1] 

机构地区：[1]兰州重离子加速器国家实验室原子核理论中心

出　　处：《高能物理与核物理》2004年第8期850-853,共4页High Energy Physics and Nuclear Physics

基　　金：国家重大基础研究发展项目 (G2 0 0 0 0 7740 0 );国家自然科学基金(10 175 0 80;10 0 0 40 12 ;10 175 0 82 );中国科学院知识创新工程重点方向项目(KJCX2 SW N0 2 )资助~~

摘　　要：利用同位旋相关的量子分子动力学模型研究了中能重离子碰撞中库仑作用对同位旋分馏过程的影响 .研究结果表明 ,在所研究的能区 ,无论是丰 (缺 )中子碰撞系统或者轻 (重 )反应系统 ,库仑作用都使同位旋分馏过程减弱 ,而这种影响主要来自于库仑作用对质子的排斥作用 ,使更多的质子发射 ,从而降低了气相中子We studied the effect of Coulomb interaction on the isospin fractionation in intermediate energy heavy ion collisions by using isospin dependence quantum molecular dynamics model (IQMD).The results show that Coulomb interaction reduces the isospin fractionation process whatever the system mass,beam energy and system neutron proton ratio are,because Coulomb interaction is repulsive for proton.The more bound protons became free under Coulomb interaction,which produces neutron poor gas phase and neutron rich liquid phase,thus isospin fractionation degree is weaken.On the contrary,the symmetry potential is repulsive for neutrons and attractive for protons in neutron rich systems.The bound neutrons more than protons became free,which produces neutron rich gas phase and neutron poor liquid phase,so the isospin fractionation degree increases.Total effects of the Coulomb interaction and symmetry potential make the isospin fractionation degree to be in between those induced by themselves individually.

关 键 词：库仑作用 同位旋分馏 对称势 量子分子动力学模型 中能重离子碰撞 

分 类 号：O571.4[理学—粒子物理与原子核物理]