Photon production from an anisotropic quark-gluon plasma

Abstract

We calculate photon production from a quark-gluon plasma which is anisotropic in momentum space including the Compton scattering, $q(\overline{q})g\ensuremath{\rightarrow}q(\overline{q})\ensuremath{\gamma}$, and annihilation, $q\overline{q}\ensuremath{\rightarrow}g\ensuremath{\gamma}$, processes. We show that for a quark-gluon plasma which has an oblate momentum-space anisotropy, $⟨{p}_{L}^{2}⟩<⟨{p}_{T}^{2}⟩$, the photon production rate has an angular dependence which is peaked transverse to the beam line. We propose to use the angular dependence of high-energy medium photon production to experimentally determine the degree of momentum-space isotropy of a quark-gluon plasma produced in relativistic heavy-ion collisions.