Photon and Eta Production in p+Pb and p+C Collisions at sqrt{sNN} = 17.4 GeV

TL;DR

This paper reports measurements of direct photon and eta meson production in p+Pb and p+C collisions at 17.4 GeV, providing upper limits on photon yields and eta production rates to inform understanding of particle production mechanisms.

Contribution

It presents the first measurements of direct photon upper limits and eta meson production in p+Pb and p+C collisions at this energy, aiding in the analysis of photon signals in heavy-ion collisions.

Findings

Upper limits on direct photon yields as a function of pT.

Determined eta meson production in p+C collisions.

Comparison with Pb+Pb collision results.

Abstract

Measurements of direct photon production in p+Pb and p+C collisions at $\sqrt{s_\mathrm{NN}} = 17.4\mathrm{GeV}$ are presented. Upper limits on the direct photon yield as a function of $p_\mathrm{T}$ are derived and compared to the results for Pb+Pb collisions at $\sqrt{s_\mathrm{NN}} = 17.3$ GeV. The production of the $\eta$ meson, which is an important input to the direct photon signal extraction, has been determined in the $\eta \rightarrow 2\gamma$ channel for p+C collisions at $\sqrt{s_\mathrm{NN}} = 17.4\mathrm{GeV}$.