Estimates for the Thermal Width of Heavy Quarkonia in Strongly Coupled Plasmas from Holography

TL;DR

This paper uses holography to analyze the imaginary part of the heavy quark potential in strongly coupled plasmas, providing insights into the thermal width of heavy quarkonia and its dependence on plasma properties.

Contribution

It revisits the thermal worldsheet fluctuation method, establishes a general connection between the imaginary potential and Wilson loop area law, and computes the potential in Gauss-Bonnet gravity.

Findings

Derived conditions for the imaginary part of the potential in classical gravity models.

Established a link between the imaginary potential and the Wilson loop area law in confining theories.

Estimated the variation of quarkonium thermal width with shear viscosity to entropy ratio.

Abstract

The gauge/gravity duality is used to investigate the imaginary part of the heavy quark potential (defined via the rectangular Wilson loop) in strongly coupled plasmas. This quantity can be used to estimate the width of heavy quarkonia in a plasma at strong coupling. In this paper the thermal worldsheet fluctuation method, proposed in [J.Noronha and A.Dumitru, Phys.\ Rev.\ Lett.\ {\bf 103}, 152304 (2009)], is revisited and general conditions for the existence of an imaginary part for the heavy quark potential computed within classical gravity models are obtained. We prove a general result that establishes the connection between this imaginary part of the potential determined holographically and the area law displayed by the Wilson loop in the vacuum of confining gauge theories. We also determine the imaginary part of the heavy quark potential in a strongly coupled plasma dual to Gauss-Bonnet gravity. This provides an estimate of how the thermal width of heavy quarkonia changes with the shear viscosity to entropy density ratio, $\eta/s$, at strong coupling.