Directed flow of isospin sensitive fragments within a modified clusterization algorithm in heavy-ion collisions  

作　　者：KUMAR Sanjeev MA Yugang 

机构地区：[1]Amity Institute of Nuclear Science and Technology,Amity University [2]Shanghai Institute of Applied Physics,Chinese Academy of Sciences,Jiading Campus

出　　处：《Nuclear Science and Techniques》2013年第5期44-49,共6页核技术（英文）

基　　金：Supported by the Chinese Academy of Sciences Support program for young international scientists(No.2010Y2JB02);National Natural Science Foundation of China(NSFC) projects (Nos.11220101005,11035009 and 10979074);the Knowledge Innovation project of the Chinese Academy of Sciences(No.KJCX2-EW-N01)

摘　　要：By extending the minimum spanning tree(MST)clusterization algorithm for the binding energy cut,the isospin asymmetry dependence of directed flow for isospin sensitive isobar pairs(neutrons-protons,3H-3He) is studied from low towards high incident energies.The modified clusterization method(MSTB) has the advantage to identify the fragments at quite early time.It enhances(reduces) the production of free nucleons(fragments) over MST method.The directed flow of isobaric pair3H-3He is more sensitive towards isospin asymmetry caused by MSTB than isobaric pair n-p.This sensitivity becomes quite strong towards the high incident energy and neutron-rich reaction system.In conclusion,the inclusion of binding energy in clusterization method for the flow studies has been uniquely important for understanding the isospin physics,especially for high density behavior of symmetry energy.By extending the minimum spanning tree （MST） clusterization algorithm for the binding energy cut, the isospin asymmetry dependence of directed flow for isospin sensitive isobar pairs （neutrons-protons, 3H-3He） is studied from low towards high incident energies. The modified clusterization method （MSTB） has the advantage to identify the fragments at quite early time. It enhances （reduces） the production of free nucleons （fragments） over MST method. The directed flow of isobaric pair 3H-3He is more sensitive towards isospin asymmetry caused by MSTB than isobaric pair n-p. This sensitivity becomes quite strong towards the high incident energy and neutron-rich reaction system. In conclusion, the inclusion of binding energy in clusterization method for the flow studies has been uniquely important for understanding the isospin physics, especially for high density behavior of symmetry energy.

关 键 词：集群化 同位旋 敏感性 重离子碰撞 流量 算法 修改 入射能量 

分 类 号：O571.6[理学—粒子物理与原子核物理]