Jet shape and redistribution of the lost energy from jets in Pb+Pb collisions at the LHC in a multiphase transport model

TL;DR

This study uses a multiphase transport model to analyze how energy lost by jets in Pb+Pb collisions at the LHC redistributes into soft particles at large angles, revealing medium response effects.

Contribution

It provides a systematic simulation-based analysis of jet energy redistribution and medium response in heavy-ion collisions, aligning with recent experimental observations.

Findings

Enhanced soft particle production at large angles in Pb+Pb collisions

Qualitative agreement with CMS experimental data

Significant energy carried by soft particles away from jet axis

Abstract

Jet-medium interaction involves two important effects: jet energy loss and medium response. The search for jet-induced medium excitations is one of the hot topics in jet quenching study in relativistic nuclear collisions. In this work, we perform a systematic study on how the lost energy from hard jets evolves with the bulk medium and redistributes in the final state of heavy-ion collisions via a multi-phase transport model. In particular, the ($\Delta \eta, \Delta \phi$) distribution of charged particles with respect to the jet axis and jet shape function are studied for various Pb+Pb collision centralities and for different transverse momentum intervals of charged particles. Our numerical result shows a strong enhancement of soft particles at large angles for Pb+Pb collisions relative to p+p collisions at the LHC, qualitatively consistent with recent CMS data. This indicates that a significant fraction of the lost energy from hard jets is carried by soft particles at large angles away from the jet axis.