Study of Isolated-photon and Jet Momentum Imbalance in $pp$ and $PbPb$ collisions

TL;DR

This paper develops a perturbative QCD and Sudakov resummation framework to analyze isolated-photon and jet momentum imbalance in $pp$ and $PbPb$ collisions, aiding the extraction of jet transport properties in quark-gluon plasma.

Contribution

It introduces a comprehensive theoretical approach combining perturbative QCD and Sudakov resummation to study gamma-jet correlations in heavy-ion collisions, including energy-loss effects and jet flavor differentiation.

Findings

Predicted enhancement of momentum imbalance in $PbPb$ compared to $pp$ collisions.

Provided a method to distinguish quark and gluon jet interactions with quark-gluon plasma.

Offered a reliable tool for extracting jet transport coefficients from experimental data.

Abstract

In this paper, we study the production of isolated-photon plus a jet in $pp$ and $PbPb$ collisions, which can be used as an important probe to the jet transport property in quark gluon plasma created in heavy ion collisions. Normally, there are two types of observables associated with the production of isolated-photon plus a jet, namely, the azimuthal angular correlation and the transverse momentum imbalance. To understand both observables in the full kinematical region, we need to employ the perturbative QCD calculation, which takes into account the hard splitting of partons, together with the Sudakov resummation formalism, which resums soft gluon splittings. Furthermore, by introducing energy-loss into the system, we calculate the enhancement of the momentum imbalance distribution for $AA$ as compared to $pp$ collisions and make predictions for future unfolded experimental data. In addition, in order to extract the jet transport coefficient more precisely in our numerical calculation, we also distinguish quark jets from gluon jets, since they interact with quark gluon plasma with different strengths. This work provides a reliable theoretical tool for the calculation of the gamma-jet correlation, which can lead us to a more precise extraction of the jet transport coefficient in relativistic heavy-ion collisions.