Measurement of Jets and Jet Suppression in sqrt(s_NN)=2.76 TeV Lead-Lead Collisions with the ATLAS detector at the LHC

TL;DR

This paper reports on measurements of jet suppression and properties in lead-lead collisions at 2.76 TeV using the ATLAS detector, revealing significant jet suppression with minimal change in fragmentation patterns.

Contribution

It provides the first detailed measurements of jet suppression and fragmentation in Pb+Pb collisions at the LHC with the ATLAS detector.

Findings

Jet yields are suppressed in central collisions for ET >100 GeV.

Fragmentation properties show little change across different jet sizes.

Jet suppression level remains consistent when using larger jet definitions.

Abstract

The first results of single jet observables in Pb+Pb collisions at sqrt(s_NN)=2.76 TeV measured with the ATLAS detector at the LHC are presented. Full jets are reconstructed with the anti-kt algorithm with R= 0.2 and 0.4, using an event-by-event subtraction procedure to correct for the effects of the underlying event including elliptic flow. The geometrically-scaled ratio of jet yields in central and peripheral events,Rcp, indicates a clear suppression of jets with ET >100 GeV. The transverse and longitudinal distributions of jet fragments is also presented. We find little no substantial change to the fragmentation properties and no significant change in the level of suppression when moving to the larger jet definition.