| High-energy heavy-ion collisions provide the possibility to produce a hot anddense nuclear matter, which mostly involved in strong interactions. Experimentally,the final state observables is the main tool as studying the evolution mechanism ofnucleus-nucleus collisions. A multiphase transport model is used to simulate Au+Aucollisions in RHIC’s beam energy scan region in this paper. The mass dependence，energy dependence and parton cross section dependence of the differential ellipticflow are discussed. The hydrodynamic calculations conclude a consistent resultregarding mass dependence. Considering the ratio of particles is calculated， theenergy dependence relation of elliptic flow is qualitatively in evidence. This couldbe due to the change of chemical composition in different energys. Involving theparton cascade and hadron cascade in AMPT, chemical composition will distinguishthe values of elliptic flow in different cross sections, which can reflect a change ofdegrees of systemic freedom.The constituent quark scaling of elliptic flow in RHIC’s beam energy scanregion has been considered as a direct evidence of quark-gluon plasma. Afterstudying the phenomenon of bayon stopping(transport), J. C. Dunlop et al. proposeda concept of transported quarks. According to the above view， the ratio oftransported quarks is calculated in this paper. Considering the flow fuction of quarks,the elliptic flow of particles and their corresponding anti-particles could berecalculated. This is an access to discussing the relation between baryon stoppingeffect and constituent quark scaling of elliptic flow. Finally, the paper gave thedifferent value between particles and their corresponding anti-particles. What’s more,compared energy dependence of the different value with experimental result. Thereis a obvious conclusion to the baryon stopping being capable to account forconstituent quark scaling violation in part, which reflect the incomplete partondegrees of freedom in these collisions. |
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