Measurements of jet quenching with semi-inclusive charged jet distributions in $Au+Au$ collisions at $\sqrt{s_{NN}}$=200 GeV

TL;DR

This paper presents measurements of jet quenching in gold-gold collisions at 200 GeV, analyzing recoil charged jets to understand energy loss, jet suppression, and intra-jet broadening, including the first search for QCD Molière scattering at RHIC.

Contribution

It introduces a novel background correction technique and provides new insights into jet quenching and Molière scattering in hot QCD matter at RHIC.

Findings

Jet yield suppression observed in recoil jets.

Evidence of intra-jet broadening.

First search for QCD Molière scattering at RHIC.

Abstract

We report measurements of jet quenching in $Au+Au$ collisions at $\sqrt{s_{NN}}$=200 GeV, based on the semi-inclusive distribution of reconstructed charged particle jets recoiling from a high $p_T$ hadron trigger. Jets are reconstructed with the anti-k$_T$ algorithm ($R$=0.2 to 0.5), with low IR-cutoff of track constituents ($p_{T}>0.2$ GeV/c). Uncorrelated background is corrected using a novel mixed-event technique, with no fragmentation bias imposed by the correction procedure on the accepted recoil jet population. Corrected recoil jet distributions, reported in the range $0<p_{T,jet}^{ch}<30$ GeV/c, are used to measure jet yield suppression, jet energy loss, and intra-jet broadening. The first search for QCD Moli\`ere scattering of jets in hot QCD matter at RHIC is reported.