Impact parameter and beam energy dependence for azimuthal asymmetry of direct photons and free protons in intermediate energy heavy-ion collisions  

作　　者：刘桂华 马余刚 蔡翔舟 方德清 沈文庆 田文栋 王鲲 

机构地区：[1]Shanghai Institute of Applied Physics, Chinese Academy of Sciences [2]Graduate University of Chinese Academy of Sciences

出　　处：《Chinese Physics C》2009年第S1期89-91,共3页中国物理C（英文版）

基　　金：Supported by National Basic Research Program of China (973 Program) (2007CB815004);Shanghai Development Foundation from Science and Technology (06JC14082, 06QA14062);National Natural Science Foundation of China (10535010, 10775167)

摘　　要：Hard photon emitted from energetic heavy ion collisions is of very interesting since it does not experience the late-stage nuclear interaction, therefore it is useful to explore the early-stage information of matter phase. In this work, we have calculated the impact parameter and beam energy dependence for azimuthal asymmetry, characterized by directed transverse flow parameter F and elliptic asymmetry coeffcient v2, of direct photons and the corresponding free protons in intermediate energy heavy-ion collisions. It is further shown the anti-correlated azimuthal asymmetry between direct photons and free protons.Hard photon emitted from energetic heavy ion collisions is of very interesting since it does not experience the late-stage nuclear interaction, therefore it is useful to explore the early-stage information of matter phase. In this work, we have calculated the impact parameter and beam energy dependence for azimuthal asymmetry, characterized by directed transverse flow parameter F and elliptic asymmetry coeffcient v2, of direct photons and the corresponding free protons in intermediate energy heavy-ion collisions. It is further shown the anti-correlated azimuthal asymmetry between direct photons and free protons.

关 键 词：hard photon azimuthal asymmetry BUU impact parameter dependence energy dependence 

分 类 号：O571.6[理学—粒子物理与原子核物理]