Azimuthal anisotropy of charged jet production in $\sqrt{s_{\rm NN}}$ = 2.76 TeV Pb-Pb collisions

Submission Date: 
24/09/2015
Article Information
Submission Form
System: 
Pb-Pb
Energy: 
2.76 TeV
Abstract Plain Text: 

 The azimuthal dependence of jet suppression provides insight into the path-length dependence of in-medium parton energy loss. This paper presents measurements of $R=0.2$ charged jet production in central and peripheral \sqrtSnn~= 2.76 TeV Pb--Pb collisions with respect to the second-order event plane, quantified as \vj. Jet finding is performed with the anti-\kt~algorithm using charged tracks from the ALICE tracking system. The contribution of background flow to the underlying event shape is taken into account event-by-event; remaining fluctuations are removed on an ensemble basis by unfolding the jet spectra for different event plane orientations independently. Significant non-zero \vj~is observed in peripheral collisions for 20 $<$ \ptjet~$<$ 90 \GeVc. The observed \vj{} in central collisions is of similar magnitude, but the uncertainties are larger and therefore the results are not significantly different from zero. The azimuthal dependence of the jet production is similar to suppression observed in measurements of $v_2$ of single charged particles at high \pt{} and \vjfull{} of full jets. Good agreement between the data and predictions from JEWEL, an energy-loss model simulating parton shower evolution in the presence of a dense QCD medium, is found in peripheral collisions.