Jet measurements in the STAR experiment

TL;DR

This paper reviews jet measurements in the STAR experiment across different collision systems, highlighting how jets serve as probes for the quark-gluon plasma and discussing the challenges and methods of jet reconstruction amidst high background.

Contribution

It provides a comprehensive overview of jet measurements in heavy-ion collisions at RHIC, including new results from reconstructed di-jets and jet-hadron correlations.

Findings

Jet quenching observed in Au+Au collisions

Medium effects modify jet structure and correlations

Background characterization is crucial for accurate measurements

Abstract

Jets are produced from hard scatterings in the early stages of heavy-ion collisions, therefore they can be exploited as probes for medium tomography. Such high-$p_T$ partons are expected to suffer energy loss in the hot and dense nuclear medium via gluon radiation or elastic collisions along their path. Jet reconstruction gives access to the kinematics of the hard scattering that produced the jet, improving our understanding of energy loss and its effect on the jet structure. Such measurements are challenging in heavy-ion collisions at RHIC, due to the large background, therefore a precise characterization of the background in Au+Au is needed. We present an overview of the results on jet measurements obtained by the STAR experiment in p+p, d+Au and central Au+Au collisions at 200 GeV. We also present results obtained with reconstructed di-jets and jet-hadron correlations as tools to study the medium effects on jet production.