Measurements of thermal photons in heavy ion collisions with PHENIX

TL;DR

This paper reports on measurements of thermal photons in heavy ion collisions using the PHENIX detector, providing insights into the quark-gluon plasma temperature and establishing a baseline with p+p collision data.

Contribution

First measurement of direct thermal photons in heavy ion collisions at RHIC, using internal conversion method, with baseline p+p data for comparison.

Findings

Thermal photon spectra observed in Au+Au collisions.

Baseline p+p photon measurements established.

Results support thermal photon production in quark-gluon plasma.

Abstract

Thermal photons are thought to be the ideal probe to measure the temperature of the quark-gluon plasma created in heavy ion collisions. PHENIX has measured direct photons with p_T < 5 GeV/c via their internal conversions into e+e- pairs in Au+Au collisions at sqrt(s_NN) = 200 GeV and has now provided a baseline measurement from p+p data.