Z+jet productions in heavy-ion collisions

TL;DR

This paper presents a comprehensive study of Z+jet correlations in heavy-ion collisions at the LHC, combining advanced theoretical models to explain experimental observations of jet modifications due to quark-gluon plasma effects.

Contribution

It introduces a combined theoretical framework using Sherpa and Linear Boltzmann transport to accurately model Z+jet production and propagation in heavy-ion collisions, aligning with CMS data.

Findings

Successfully reproduces CMS measurements of Z+jet correlations

Highlights importance of high-order corrections at high energies

Shows jet suppression and azimuthal modifications in Pb+Pb collisions

Abstract

We report a systematic study of Z+jet correlation in Pb+Pb collisions at the LHC by combining the next-leading-order matrix elements calculations with matched parton shower in Sherpa for the initial Z+jet production, and Linear Boltzmann transport Model for jet propagation in the expanding quark-gluon-plasma. Our numerical results can well explain CMS measurements on Z+jet correlation in Pb+Pb collisions: the shift of $p_T$ imbalance $x_{jZ}=p_T^{jet}/p_T^Z$ and their mean values, the suppression of the average number of jet partners per Z boson $R_{jZ}$, as well as the modification of azimuthal angle correlations $\Delta \phi_{jZ}$. We also demonstrate that high-order corrections play a significant role in the understanding of Z+jet correlations at high energies.