QCD相结构的全息模型研究  

QCD phase structure from holographic models

作　　者：朱洲润 赵彦清 侯德富 ZHU Zhourun;ZHAO Yanqing;HOU Defu(Institute of Particle Physics and Key Laboratory of Quark and Lepton Physics(MOS),Central China Normal University,Wuhan 430079,China)

机构地区：[1]夸克与轻子教育部重点实验室华中师范大学粒子物理研究所,武汉430079

出　　处：《核技术》2023年第4期88-95,共8页Nuclear Techniques

基　　金：国家重点研发(No.2022YFA1604900);国家自然科学基金(No.11735007,No.11890711,No.11890710,No.12275104)资助。

摘　　要：探寻量子色动力学(Quantum Chromodynamics,QCD)相结构一直是高能重离子碰撞物理研究的重要目标。近年来,转动背景下的QCD相变引起了研究者们的关注。本文基于AdS/QCD对偶,研究了化学势、角速度对QCD临界点的影响。研究发现:化学势减小了临界转速ωc,角速度降低了μc和相变温度。我们通过计算一些可以表征QCD相变的探针,如拖曳力、扩散系数、喷注淬火参数和J/ψ的谱函数,发现喷注淬火参数和拖曳力在相变温度附近有增强,峰值所对应的温度随着化学势的增加降低,这与相图中相变温度随化学势增加而降低相对应。谱函数的结果表明,磁场促进重介子的溶解,使末态J/ψ产额的压低更明显。我们研究了早期宇宙QCD全息相变产生的引力波,发现胶子凝聚抑制了引力波的能量密度,峰值频率位置随着胶子凝聚增加而下降。We aim to study the effects of chemical potential and angular velocity on the critical endpoint of quantum chromodynamics(QCD).We used several probes(drag force,jet quenching parameter,heavy vector meson spectral function)to characterize the phase transition and studied gravitational waves from the holographic QCD phase transition in the early universe.We used different holographic QCD models to discuss the QCD phase transition,energy loss,spectral function,and gravitational waves.We found that the chemical potential and angular velocity changed the location of the critical endpoint,and the drag force and jet quenching parameter were temperature dependent and enhanced near the phase transition temperature.The magnetic field had a nontrivial effect on the spectral function.We conclude that the chemical potential decreasesωc,and the angular velocity decreasesμc and the phase transition temperature.The jet quenching parameter and drag force can characterize the phase transition,and the magnetic field promotes the dissociation of heavy vector mesons.Moreover,the energy density of gravitational waves decreases as the gluon condensate increases,and the peak frequency shifts downward with increasing gluon condensate.Exploring the phase structure of QCD is an important task in high-energy heavy ion collision physics,and recently,there has been considerable interest in the QCD phase transition for rotating backgrounds.

关 键 词：相变 能量损失 谱函数 引力波 

分 类 号：TL99[核科学技术—核技术及应用]