The L-dependence of the static potential between Nc quarks arranged in a circle of radius L (a "baryon") immersed in the hot plasma of a gauge theory with Nc colors defines a screening length Ls. We use the AdS/CFT correspondence to compute this screening length for the case of heavy quarks in the plasma of strongly coupled N=4 super Yang-Mills theory moving with velocity v relative to the baryon. We find that in the v -> 1 limit, Ls \propto (1-v^2)^{1/4}/T, and find that corrections to this velocity dependence are small at lower velocities. This result provides evidence for the robustness of the analogous behavior of the screening length defined by the static quark-antiquark pair, which has been computed previously and in QCD is relevant to quarkonium physics in heavy ion collisions. Our results also show that as long as the hot wind is not blowing precisely perpendicular to the plane of the baryon configuration that we analyze, the Nc different quarks are not all affected by the wind velocity to the same degree, with those quarks lying perpendicular to the wind direction screened most effectively.
Gauge-invariant screening masses and static quark free energies in $N_f = 2+1$ QCD at non-zero baryon density
我们讨论了夸克-胶子等离子体中规范不变的电磁屏蔽质量在有限重子密度情况下的推广，用Polyakov圈子矩阵定义它们。我们给出了具有物理夸克质量的$N_f=2+1$ QCD的格点结果，用虚化学势方法得到，结果表明屏蔽质量随$μ_B$的增加而增加。一个单独的分析进行了理论上有趣的情况下$μ_B/T=3 i π$，其中电荷共轭没有明确打破和通常的定义的屏蔽质量可以用于温度低于罗伯特-魏斯过渡。最后，我们研究了静态夸克自由能对重子化学势的依赖关系，表明它是$μ_B$的递减函数，并在接近$μ_B=0$的赝临界转变温度时表现出特殊的行为。
Uncertainty quantification of holographic transport and energy loss for the hot and baryon-dense QGP
University of Houston（休斯顿大学）；Universidade Federal do Rio de Janeiro（里约热内卢联邦大学）；University of Illinois Urbana-Champaign（伊利诺伊大学厄巴纳-香槟分校）；Kent State University（肯特州立大学）；Centro Brasileiro de Pesquisas Físicas（巴西物理研究中心）；Universidade Federal de Goiás（戈亚斯联邦大学）
Fermions obstruct dimensional reduction in hot QCD
本文首次研究了在1.5Tc < T <3Tc（T_c为手征跃迁发生的温度）范围内，由四种夸克轻动力学味的量子色动力学类胶球凝聚子得到的屏蔽质量。我们还研究了类π介子和类σ屏蔽质量，发现它们在整个T范围内都是简并的。这些阻碍微扰降维，因为最低的胶球屏蔽质量比它们重。我们的结果外推表明，这种阻碍可能会影响整个温度范围内预期达到甚至在大型强子对撞机。
利用对偶弦论，我们研究了在重子平面上吹的N=4强耦合杨-米尔斯等离子体风中的圆形重子位形，一个夸克与之解离前后的情况.一个足够简单的模型是当重子中有四个夸克时，它能捕捉到许多有趣的特征.作为迈向唯象学的一步，我们比较了有代表性的离解构型，并对它们的能量学和其他性质作了一些评论。我们发现的相关结果包括：以前对其它色单重态得到的屏蔽长度公式L_s T ~（1-v^2）^{1/4}对圆形重子也是稳健的。
