CERN Accelerating science

ATLAS Slides
Report number	ATL-PHYS-SLIDE-2022-109
Title	Novel Measurements of Dijet Quenching with ATLAS
Author(s)	Rinn, Timothy Thomas (Brookhaven National Laboratory (US))
Corporate author(s)	The ATLAS collaboration
Collaboration	ATLAS Collaboration
Submitted to	29th International Conference on Ultra-relativistic Nucleus-Nucleus Collisions, Krakow, Poland, 4 - 10 Apr 2022, pp.ATL-PHYS-SLIDE-2022-109
Submitted by	[email protected] on 11 May 2022
Subject category	Particle Physics - Experiment
Accelerator/Facility, Experiment	CERN LHC ; ATLAS
Free keywords	HEAVYIONS
Abstract	High energy partons are well established to lose energy when traversing the hot and dense medium produced in heavy-ion collisions. This results in a modification to the transverse momentum distributions of jets, producing a phenomenon known as jet quenching. It has been previously established in Pb+Pb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV that jet quenching results in significant modifications to the transverse momentum balance of dijet pairs. More differential measurements are needed to better understand the asymmetric jet quenching observed and explore the role of energy loss fluctuations and path-length dependent energy loss. In this talk, we report new, fully unfolded measurements of the dijet momentum balance in Pb+Pb and pp collisions at $\sqrt{s_{NN}}$ = 5.02 TeV with extended kinematic reach over previous publications, as well as in Xe+Xe collisions at $\sqrt{s_{NN}}$ = 5.44 TeV. This talk will additionally present a new observable, the nuclear modification factor of subleading and leading jets, which provides a precise quantification of asymmetric energy loss experienced by dijets.