Tea Time 学术活动系列邀请报告(83)Effect of volume corrections on cumulants of multiplicity distributions

报告题目：Effect of volume corrections on cumulants of multiplicity distributions

报告人：徐浩洁 博士 （北京大学）
时  间：1月6日（星期五）下午13:30-15:00
地  点：3-323

报告人简介：

    徐浩洁，博士，2006年本科毕业于合肥工业大学，2012年博士毕业于�中国科学技术大学粒子物理与核物理专业,2012.6-至今先后在中国科学技术大学和�北京大学从事博士后研究。徐浩洁博士的研究内容主要为相对论重离子碰撞中的现象学、�相对论流体力学模拟、电磁探针和重味探针、逐事例粒子多重数涨落等。 

报告摘要：

    High order cumulants of multiplicity fluctuations are expected to provide us some crucial information about the phase diagram of Quantum Chromodynamics. Besides the fluctuation data and theoretical studies on critical fluctuations, it is clear that the theoretical baselines from non-critical statistical fluctuation studies are also important. In this talk, I investigate the non-critical volume corrections on the cumulants of net-charge distributions and net-proton distributions reported by the STAR collaboration.
From a general formalism in statistical model, I find that the volume corrections play crucial role on the cumulants of net-charge distributions: the corrected cumulant products Sσ and κσ2 of net-charge distributions are about four times as large as the Skellam expectations. The effect of volume corrections on cumulants of net-proton distributions can be neglected at the top RHIC energy, but, as the collision energy decreases, it make substantially contributions to the high order cumulants . Recently, I implement this idea to Monte Carlo hadron resonance gas (MCHRG) simulations. Based on the MCHRG calculations, I find that the large deviations of Sσ and κσ2 of net charge distributions from Skellam expectations are mainly due to the effect of volume corrections, which are consist with the previous statistical studies. While the deviations of scale variances ω are mainly due to the effect of resonance decays.