Study of neutron density fluctuation and neutron-proton correlation in Au+Au collisions using PYTHIA8/Angantyr  

作　　者：张祖满 李莎 喻宁 林健平 李双 汤思宇 周代翠 Zuman Zhang;Sha Li;Ning Yu;Jianping Lin;Shuang Li;Siyu Tang;Daicui Zhou(School of Physics and Mechanical Electrical&Engineering,Hubei University of Education,Wuhan 430205,China;Institute of Theoretical Physics,Hubei University of Education,Wuhan 430205,China;Key Laboratory of Quark and Lapten Physics(MOE),Central China Normal University,Wuhan 430079,China;College of Science,China Three Gorges University,Yichang 443002,China;Center for Astronomy and Space Sciences,China Three Gorges University,Yichang 443002,China;School of Mathematical&Physical Sciences,Wuhan Textile University,Wuhan 430200,China)

机构地区：[1]School of Physics and Mechanical Electrical&Engineering,Hubei University of Education,Wuhan 430205,China [2]Institute of Theoretical Physics,Hubei University of Education,Wuhan 430205,China [3]Key Laboratory of Quark and Lapten Physics(MOE),Central China Normal University,Wuhan 430079,China [4]College of Science,China Three Gorges University,Yichang 443002,China [5]Center for Astronomy and Space Sciences,China Three Gorges University,Yichang 443002,China [6]School of Mathematical&Physical Sciences,Wuhan Textile University,Wuhan 430200,China

出　　处：《Chinese Physics C》2023年第11期62-67,共6页中国物理C（英文版）

基　　金：Supported in part by the Natural Science Foundation of Henan Province,China (212300410386);the Key Research Projects of Henan Higher Education Institutions (20A140024);the Scientific Research Foundation of Hubei University of Education for Talent Introduction (ESRC20220028,ESRC20230002);the NSFC(12005114);NSFC key Grant (12061141008);the Key Laboratory of Quark and Lepton Physics (MOE) in the Central China Normal University(QLPL2022P01)

摘　　要：Utilizing the PYTHIA8 Angantyr model,which incorporates the multiple-parton interaction(MPI)based color reconnection(CR)mechanism,we study the relative neutron density fluctuation and neutron-proton correlation in Au+Au collisions at√sNN=7.7,11.5,14.5,19.6,27,39,62.4,and 200 GeV.In this study,we not only delve into the dependence of these two remarkable observations on rapidity,centrality,and energy,but also analyze their interplay with the MPI and CR.Our results show that the light nuclei yield ratio of protons,deuterons,and tritons,expressed by the elegant expression N_(t)N_(p)/N^(d)^(2),remains unchanged even as the rapidity coverage and collision centrality increase.Interestingly,we also reveal that the effect of CR is entirely dependent on the presence of the MPI;CR has no impact on the yield ratio if the MPI is off.Our findings further demonstrate that the light nuclei yield ratio experiences a slight increase with increasing collision energy,as predicted by the PYTHIA8 Angantyr model;however,it cannot describe the non-monotonic trend observed by the STAR experiment.Based on the Angantyr model simulation results,it is essential not to overlook the correlation between neutron and proton fluctuations.The Angantyr model is a good baseline for studying collisions in the absence of a quark-gluon plasma system,given its lack of flow and jet quenching.

关 键 词：relativistic heavy-ion collisions quark deconfinement quark-gluon plasma production phase transitions 

分 类 号：O572.342[理学—粒子物理与原子核物理]