Screening length in plasma winds

TL;DR

This paper analyzes how the screening length of a heavy quark-antiquark pair in strongly coupled plasma flows depends on velocity and background geometry, revealing universal scaling behaviors via AdS/CFT.

Contribution

It develops a general analytical method to determine the scaling exponent of the screening length in various holographic backgrounds, including conformal and non-conformal theories.

Findings

In conformal theories, the screening length scales as (boosted energy density)^{-1/d}.

The scaling exponent deviates from -1/d in non-conformal theories, correlating with the speed of sound.

The method applies to R-charged black holes, Schwarzschild-AdS, Klebanov-Tseytlin, and Dp-brane geometries.

Abstract

We study the screening length L_s of a heavy quark-antiquark pair in strongly coupled gauge theory plasmas flowing at velocity v. Using the AdS/CFT correspondence we investigate, analytically, the screening length in the ultra-relativistic limit. We develop a procedure that allows us to find the scaling exponent for a large class of backgrounds. We find that for conformal theories the screening length is (boosted energy density)^{-1/d}. As examples of conformal backgrounds we study R-charged black holes and Schwarzschild-anti-deSitter black holes in (d+1)-dimensions. For non-conformal theories, we find that the exponent deviates from -1/d and as examples we study the non-extremal Klebanov-Tseytlin and Dp-brane geometries. We find an interesting relation between the deviation of the scaling exponent from the conformal value and the speed of sound.