QCD临界点附近的动力学临界涨落

Critical dynamical fluctuations near the QCD critical point

探寻量子色动力学(Quantum Chromodynamics,QCD)相图的临界点是相对论重离子碰撞实验低能量扫描(Beam Energy Scan program in Relativistic Heavy-Ion Collisions,RHIC-BES)项目的重要实验目标。初步的实验探测发现了净质子数涨落随着对撞能量的非单调行为,定性上符合基于静态模型的理论预言,这暗示着QCD临界点的存在。由于相对论重离子碰撞是一个高速膨胀的体系,动力学效应能显著地改变QCD临界点附近的临界涨落。为最终确定QCD临界点的存在以及研究QCD在有限温有限密区域的相结构,人们发展了一系列QCD临界点附近的动力学模型。本文回顾了近年来关于寻找QCD临界点在实验测量和理论模型的进展,着重强调在临界点及一级相变区域动力学模型的发展和挑战。

The exploration of the critical point on the QCD(Quantum Chromodynamics)phase diagram is one of the most important goals of the beam energy scan program in relativistic heavy-ion collisions(RHIC-BES).Preliminary experimental measurement observed the non-monotonic behavior of net-proton fluctuations as a function of collision energy,which qualitatively agrees with the prediction of the static theoretical models and this hints the existence of the QCD critical point.The system created in heavy-ion collision is highly expanding system with which the dynamical effects dramatically modify the critical fluctuations near the QCD critical point.To confirm the existence of QCD critical point and study the phase structure of QCD system at finite temperature and finite density region,a series of dynamical models near the QCD critical point has been developed.This paper reviews the recent developments related to the exploration of the QCD critical point from experimental and theoretical viewpoints.In particular,we emphasize on the developments and challenges of the dynamical model near the QCD critical point and the first-order phase transition.