Rivet Analysis of Low-Momentum Direct Photon Yield from Au+Au Collisions*

At the Relativistic Heavy Ion Collider (RHIC) beams of ionized particles are collided into each other at nearly the speed of light. Due to the extremely high energy of these collisions, the particles go beyond the boundary of maintaining hadronic form, thus momentarily creating a quark gluon plasma (QGP) which can be studied. Photons are an extremely useful probe of the QGP due to their large mean free path in the medium, allowing them to travel non-interactively through the strongly dominated material. The PHENIX collaboration measured the photons and other particles produced in heavy ion collisions at multiple energies during the beam energy scan at RHIC. The Robust Independent Validation of Experimental and Theory program (RIVET) uses Monte Carlo modelling as a means of comparison to the experimental data. We used Rivet to make comparisons between low-momentum (0.4 < p_T < 3 GeV/c) direct-photon yields from Au+Au collisions at various energies and several other collision systems measured by PHENIX. These yields are analyzed and plotted along with their respective comparisons to theoretical models via RIVET and the results are discussed.