Fluctuations and asymmetric jet events in PbPb collisions at the LHC

TL;DR

This paper investigates how background fluctuations influence jet asymmetry measurements in PbPb collisions at the LHC, emphasizing the importance of accurately estimating these fluctuations for understanding jet quenching.

Contribution

It highlights the sensitivity of jet asymmetry to background fluctuations and discusses how analysis choices affect the interpretation of jet quenching data.

Findings

Background fluctuations significantly impact jet asymmetry measurements.

Estimating true fluctuations is crucial for accurate jet quenching analysis.

The choice of low-pt threshold affects the perceived influence of fluctuations.

Abstract

Recent LHC results concerning full jet-quenching in PbPb collisions have been presented in terms of a jet asymmetry parameter, measuring the imbalance between the transverse momenta of leading and subleading jets. We examine the potential sensitivity of this distribution to fluctuations from the heavy-ion background. Our results suggest that a detailed estimate of the true fluctuations would be of benefit in extracting quantitative information about jet quenching. We also find that the apparent impact of fluctuations on the jet asymmetry distribution can depend significantly on the choice of low-pt threshold used for the simulation of the hard pp events.