Measurement of inclusive jet charged-particle fragmentation functions in Pb+Pb collisions at $\sqrt{s_{NN}}=2.76$ TeV with the ATLAS detector

Abstract

Measurements of charged-particle fragmentation functions of jets produced in ultra-relativistic nuclear collisions can provide insight into the modification of parton showers in the hot, dense medium created in the collisions. ATLAS has measured jets in $\sqrt{s_{NN}}=2.76$ TeV Pb+Pb collisions at the LHC using a data set recorded in 2011 with an integrated luminosity of 0.14 nb${}^{-1}$. Jets were reconstructed using the anti-$k_t$ algorithm with distance parameter values $R$ = 0.2, 0.3, and 0.4. Distributions of charged-particle transverse momentum and longitudinal momentum fraction are reported for seven bins in collision centrality for $R=0.4$ jets with $p_T^{\mathrm{jet}}>100$ GeV. Commensurate minimum $p_{\mathrm{T}}$ values are used for the other radii. Ratios of fragment distributions in each centrality bin to those measured in the most peripheral bin are presented. These ratios show a reduction of fragment yield in central collisions relative to peripheral collisions at intermediate $z$ values, $0.04\lesssim z\lesssim 0.2$ and an enhancement in fragment yield for $z\lesssim 0.04$. A smaller, less significant enhancement is observed at large $z$ and large $p_{\mathrm{T}}$ in central collisions.

17 pages plus author list + cover pages (32 pages total), 8 figures, 4 tables, published in Physics Letters B 739 (2014) 320-342. All figures including auxiliary figures are available at http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HION-2012-08/

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Cited by in corpus (12)

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• Medium response in JEWEL and its impact on jet shape observables in heavy ion collisions
• Measurement of the production and lepton charge asymmetry of $\text{W}$ bosons in Pb+Pb collisions at $\sqrt{s_{\mathbf{NN}}}=$ 2.76 TeV with the ATLAS detector
• Using hadron-in-jet data in a global analysis of $D^{\ast }$ fragmentation functions
• Jet-like correlations with neutral pion triggers in pp and central Pb-Pb collisions at 2.76 TeV
• An overview of experimental results from ultra-relativistic heavy-ion collisions at the CERN LHC: hard probes
• Disappearance of the Mach Cone in heavy ion collisions
• Theory of Jet Quenching in Ultra-Relativistic Nuclear Collisions
• Medium-induced jet evolution: wave turbulence and energy loss
• Multi-particle correlations and KNO scaling in the medium-induced jet evolution
• In-medium parton branching beyond eikonal approximation