The Symmetry Energy from the Neutron-Rich Nucleus Produced in the Intermediate-Energy 40,48Ca and 58,64Ni Projectile Fragmentation  

作　　者：MA Chun-Wang PU Jie WANG Shan-Shan WEI Hui-Ling 马春旺;普洁;王闪闪;魏慧玲(Department of Physics,Henan Normal University,Xinxiang 453007)

机构地区：[1]Department of Physics,Henan Normal University,Xinxiang 453007

出　　处：《Chinese Physics Letters》2012年第6期90-93,共4页中国物理快报（英文版）

基　　金：Supported by the National Natural Science Foundation of China under Grant No 10905017;the Program for Innovative Research Team(in Science and Technology)under Grant No 2010IRTSTHN002 in the Universities of Henan Province,and the Young Teacher Project in Henan Normal University.

摘　　要：In the framework of a modified Fisher model,using the isobaric yield ratio method,we investigate the fragments produced in the 140 A Me V 40,48Ca+9Be and 58,64Ni+9Be projectile fragmentation reactions.Using different approximation methods,asym/T (the ratio of symmetry-energy coefficient to temperature) of symmetric and neutron-rich fragments are extracted.It is found that asym/T of fragments depend on the reference nucleus and the neutron excess of fragments.The asym/T of the isobar decreases when the neutron-excess of the isobar increases,while for a fragment with the same neutron-excess,asym/T increases as the mass of the fragment increases but saturate when the mass of the fragment becomes larger.

关 键 词：EXCESS SYMMETRY FRAGMENTATION 

分 类 号：O57[理学—粒子物理与原子核物理]