Velocity Dependence of Baryon Screening in a Hot Strongly Coupled Plasma

TL;DR

This paper uses AdS/CFT to analyze how the screening length of a baryon in a hot plasma depends on velocity, revealing a universal velocity dependence and directional effects relevant to quarkonium physics in heavy ion collisions.

Contribution

It provides the first detailed computation of velocity-dependent baryon screening length in a strongly coupled plasma using holography, extending previous quark-antiquark results.

Findings

Screening length scales as (1-v^2)^{1/4}/T at high velocities.

Velocity corrections are small at lower velocities.

Directional dependence affects quark screening effectiveness.

Abstract

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.