Thermal Width of the $\Upsilon$ at Large t' Hooft Coupling

TL;DR

This paper uses AdS/CFT correspondence to demonstrate that heavy quarkonium states like the $$ acquire a thermal width at strong coupling, affecting their suppression in heavy-ion collisions.

Contribution

It introduces a method to compute the imaginary part of the heavy quark potential at strong coupling using holography, revealing thermal effects on quarkonia.

Findings

Heavy quark potential develops an imaginary part at finite temperature.

Deeply bound $$ states gain a thermal width at large t'Hooft coupling.

Predicted suppression of $$ in heavy-ion collisions.

Abstract

We use the AdS/CFT correspondence to show that the heavy quark (static) potential in a strongly-coupled plasma develops an imaginary part at finite temperature. Thus, deeply bound heavy quarkonia states acquire a small nonzero thermal width when the t'Hooft coupling $\lambda=g^2 N_c \gg 1$ and the number of colors $N_c \to \infty$. In the dual gravity description, this imaginary contribution comes from thermal fluctuations around the bottom of the classical sagging string in the bulk that connects the heavy quarks located at the boundary. We predict a strong suppression of $\Upsilon$'s in heavy-ion collisions and discuss how this may be used to estimate the initial temperature.