Jet Quenching via Jet Collimation

TL;DR

This paper proposes a jet collimation mechanism to explain dijet modifications in heavy ion collisions, suggesting that medium-induced soft component trimming accounts for observed asymmetries with realistic quenching parameters.

Contribution

It introduces a simple kinematic model of jet collimation that links soft component trimming to observed dijet asymmetries in heavy ion collisions.

Findings

The mechanism explains dijet asymmetry with realistic $\hat{q} L$ values.

Soft components of jets are efficiently trimmed by the medium.

The model aligns with experimental data from ATLAS.

Abstract

The ATLAS Collaboration recently reported strong modifications of dijet properties in heavy ion collisions. In this work, we discuss to what extent these first data constrain already the microscopic mechanism underlying jet quenching. Simple kinematic arguments lead us to identify a frequency collimation mechanism via which the medium efficiently trims away the soft components of the jet parton shower. Through this mechanism, the observed dijet asymmetry can be accomodated with values of $\hat{q}\, L$ that lie in the expected order of magnitude.