Jet properties from direct $\gamma$ - hadron correlation in PHENIX at RHIC

TL;DR

This paper uses direct photon-hadron correlations in p+p collisions at RHIC to study the away-side parton fragmentation function, providing insights into parton dynamics and testing pQCD predictions.

Contribution

It introduces a method to constrain the initial momentum of away-side partons using direct photon triggers, enabling detailed fragmentation function measurements.

Findings

Direct photon associated yields are measured and compared with PYTHIA simulations.

The effect of $k_{T}$ smearing on the spectra is analyzed.

Results support the use of photon-hadron correlations as a tool for parton fragmentation studies.

Abstract

Two-particle correlations of direct photon triggers with associated hadrons are obtained by isolation method in p+p collisions at \sqrt{s} = 200 GeV in PHENIX at RHIC. The initial momentum of the away-side parton is tightly constrained, because the parton-photon pair is balanced in momentum at the leading order in perturbative quantum chromodynamics (pQCD). Therefore making such correlations can be used as a tool to measure the away-side parton fragmentation function. The direct photon associated yields in p+p collisions are compared with PYTHIA and the effect of the $k_{T}$ smearing in the spectra is discussed.