Long-time drift of the isospin degree of freedom in heavy ion collisions
Long-time drift of the isospin degree of freedom in heavy ion collisions
复制标题
重离子碰撞中同位旋自由度的长时间漂移
DOI：
10.1103/physrevc.95.041602
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发表时间：
2017
影响因子：
3.1
通讯作者：
Yan
中科院分区：
文献类型：
--
作者：
Zhang Yan;Tian Junlong;Cheng Wenjing;Guan Fenhai;Huang Yan;Li Hongjie;Lu Liming;Wang Rensheng;Wang Yijie;Wu Qianghua;Yi Han;Zhang Zhao;Zhao Yixuan;Duan Limin;Hu Rongjiang;Huang Meirong;Jin Genming;Jin Shilun;Lu Chengui;Ma Junbing;Ma Peng;Wang Jiansong;Yan
通过对重离子碰撞中产生的轻带电粒子（LCP）的同位旋组成的大范围角分布和束流能量依赖关系，对同位旋自由度（IDOF）的漂移进行了实验可视化。结果表明，从早期的动态发射到统计蒸发一直持续到非常晚的阶段，整个过程都存在净同位旋输运。由于同位旋效应的长期积累，lcp上相对中子过剩和的角分布被用作对称能的敏感探测。当S固定在28.3 MeV时，利用改进的量子分子动力学输运模型附带统计发射加力燃烧器，间接推导出ρ0时L= 33-61 MeV（0.95保密水平）的软密度依赖关系。
The drift of the isospin degree of freedom (IDOF) is experimentally visualized through the wide-range angular distribution and the beam energy dependence of the isospin composition of light charged particles (LCP) produced in heavy ion collisions. It is evidenced that the net isospin transport is presented in the whole process from early dynamic emission to the statistical evaporation lasting to very late stage. Due to the long-time accumulation of the isospin effect, the angular distribution of the relative neutron excess summing over the LCPs is utilized as a sensitive probe to the symmetry energy. With S fixed at 28.3 MeV, a soft density dependence with L=33–61 MeV (0.95 confidential level) at ρ0 is circumstantially deduced using an improved quantum molecular dynamics transport model attached with a statistical emission afterburner.