Isoscaling properties for neutron-rich fragments in highly asymmetric heavy ion collision systems  

作　　者：彭丹 马春旺 乔春源 刘星泉 魏慧玲 Dan Peng;Chun-Wang Ma;Chun-Yuan Qiao;Xing-Quan Liu;Hui-Ling Wei(Institute of Particle and Nuclear Physics,College of Physics,Henan Normal University,Xinxiang 453007,China;Institute of Nuclear Science and Technology,Henan Academy of Sciences,Zhengzhou 450046,China;Key Laboratory of Radiation Physics and Technology of the Ministry of Education,Sichuan University,Chengdu 610064,China)

机构地区：[1]Institute of Particle and Nuclear Physics,College of Physics,Henan Normal University,Xinxiang 453007,China [2]Institute of Nuclear Science and Technology,Henan Academy of Sciences,Zhengzhou 450046,China [3]Key Laboratory of Radiation Physics and Technology of the Ministry of Education,Sichuan University,Chengdu 610064,China

出　　处：《Chinese Physics C》2024年第6期136-144,共9页中国物理C（英文版）

基　　金：Supported by the National Natural Science Foundation of China(12375123,11975091);the Program for Innovative Research Team(in Science and Technology)in University of Henan Province(21IRTSTHN011),China。

摘　　要：Traditionally,isoscaling has been interpreted and applied within the framework of the grand canonical ensemble,based on the assumption that fragment production occurs following the attainment of a statistical equilibrium state.However,the influence of the symmetry energy can lead to differences in the neutron and density distribution in neutron-rich nuclei.This in turn may impact the iso scaling parameters(usually denoted byαandβ).We examine the isoscaling properties for neutron-rich fragments produced in highly asymmetric systems on inverse kinematics,namely^(40,48)Ca and ^(58,64)Ni+^(9)Be at 140 MeV per nucleon.We evaluate α and β values and sort them as a function of the neutron excess I≡N-Z.The significant differences in a extracted from fragments within different ranges of I emphasize the importance of understanding the dependence of isoscaling parameters on fragments generated in various collision regions.Furthermore,the|β(N)|/α(Z)value for a specific fragment in small size and highly iso spin asymmetry systems can serve as a probe to detect the variations in neutron density and proton density in different regions of the nucleus and indicate the limitations of theoretical models in investigating these issues.

关 键 词：ISOSCALING symmetry energy nuclear density neutron-rich fragment heavy ion collision 

分 类 号：O571.6[理学—粒子物理与原子核物理]