The Simulation Study Of Final-state Particals’F-B Multiplicity Correlations In (S_NN)^1/2=200 GeV Au+Au Collisions

High energy heavy-ion collision is an important experimental method to explore properties of nuclear matter at high density and high temperature. People are interested in generation mechanism of hadrons and evolution process of the system in collisions. But it’s hard to observe the process derectly since it is so complicated. AMPT model, which contains interaction both on hardon level and on parton level, is one of many models that people built to simulate high energy heavy-ion collisions. Rapidity correlations have been seen in experiments, but generation mechanism of it has not been confirmed. Study on rapidity correlations is helpful to get inatial information of the sources in high energy heavy-ion collisions.A general way to study rapidity correlations is to analyse F-B(Forward-Backward) multiplicity correlations in rapidity(or pseudorapidity). Correlation strength can be expressed as ratio of backward- forward dispersions and forward-forward dispersions.NNs =200 Ge V Au+Au collisions are simulated using Default AMPT model in this thesis, correlation strength of different centrality and different pseudorapidity gaps are calculated using average method and profile methed, and results are analised. Correlation strength got using average method is independent with centrality and pseudorapidity gaps, almost a constant. Profile method is affected by cut in profile, and correlation strength in different pseudorapidity gaps have different orders, especially in Long-Range Correlations. From the analysis, for central collisions, F-B correlation strength will decrease with the increase of pseudorapidity gaps, and for non-central collisions, correlation strength is quite small, which is similar with the simulation of HIJIN G. Correlations of same charged particals are compared, pions are the majority of final-state particles, so they have similar correlation strength distributions with that of all charged final-state particals. Correlations between kaons and between protons are very week, and correlation strength increases with the increase of centrality, which is Contrary to expectations. Two methods are compared, and the profile method has better performance to describe rapidity correlations with experiment, but the method still has limitations, and it needs improvement.