Prompt photons from relativistic heavy ion collisions

We calculate the inclusive cross section for prompt photon production in heavy-ion collisions at RHIC energies $(\sqrt{s}=130\mathrm{}$ GeV and $\sqrt{s}=200\mathrm{}$ GeV) in the central rapidity region including next-to-leading order, $O\left({\alpha }_{\mathrm{em}}{\alpha }_s^2\right),$ radiative corrections, initial state nuclear shadowing, and parton energy loss effects. We show that there is a significant suppression of the nuclear cross section, up to ∼30% at $\sqrt{s}=200\mathrm{}$ GeV, due to shadowing and medium induced parton energy loss effects. We find that the next-to-leading order contributions are large and have a strong $p_t$ dependence.