Thermal suppression of moving heavy quark pairs in strongly coupled plasma

Abstract

The imaginary part of the heavy quark-antiquark potential experienced by moving heavy quarkonia in strongly coupled plasmas dual to theories of gravity is computed by considering thermal worldsheet fluctuations of the holographic Nambu-Goto string. General results for a wide class of gravity duals are presented and an explicit formula for $\mathrm{Im} \, V_{Q\bar{Q}}$ is found in the case where the axis of the moving $\bar{Q}Q$ pair has an arbitrary orientation with respect to its velocity in the plasma. These results are applied to the study of heavy quarkonia propagating through a strongly coupled $\mathcal{N} = 4$ SYM plasma. Our results indicate that the onset of $\mathrm{Im} \, V_{Q\bar{Q}}$ decreases with increasing rapidity (though our analysis is limited to slowly moving quarkonia) and that, in general, a $Q\bar{Q}$ pair is more strongly bound if its axis is aligned with its direction of motion through the strongly coupled plasma.