Direct-Photon Production in p+p Collisions at sqrt(s)=200 GeV at Midrapidity

TL;DR

This paper reports measurements of direct-photon production in proton-proton collisions at 200 GeV, extending the transverse momentum range and comparing results with theoretical calculations and other experiments.

Contribution

It provides new measurements of direct-photon cross sections at higher transverse momentum and compares them with NLO pQCD calculations and previous data.

Findings

Good agreement with NLO pQCD calculations.

Extended the transverse momentum range beyond previous measurements.

Data aligns with other experiments when expressed versus x_T.

Abstract

The differential cross section for the production of direct photons in p+p collisions at sqrt(s)=200 GeV at midrapidity was measured in the PHENIX detector at the Relativistic Heavy Ion Collider. Inclusive-direct photons were measured in the transverse-momentum range from 5.5--25 GeV/c, extending the range beyond previous measurements. Event structure was studied with an isolation criterion. Next-to-leading-order perturbative-quantum-chromodynamics calculations give a good description of the spectrum. When the cross section is expressed versus x_T, the PHENIX data are seen to be in agreement with measurements from other experiments at different center-of-mass energies.