Plasma photoemission from string theory

Abstract

Leading ’t Hooft coupling corrections to the photoemission rate of the planar limit of a strongly-coupled N = 4 SYM plasma are investigated using the gauge/string duality. We consider the full O(α ′3 ) type IIB string theory corrections to the supergravity action, including higher order terms with the Ramond-Ramond five-form field strength. We extend our previous results presented in [1]. Photoemission rates depend on the ’t Hooft coupling, and their curves suggest an interpolating behaviour from strong towards weak coupling regimes. Their slopes at zero light-like momentum give the electrical conductivity as a function of the ’t Hooft coupling, in full agreement with our previous results of [2]. Furthermore, we also study the effect of corrections beyond the large N limit.