Study of jet-medium interactions using jet shape observables in heavy ion collisions at LHC energies with JEWEL

Abstract

Based on a pQCD inspired dynamical model of jet-medium interactions, Jewel, we have studied possible modifications to inclusive jet yields and a set of jet shape observables, namely, the fragmentation functions and radial momentum distributions when jets propagate through a deconfined partonic medium created in collisions of heavy nuclei at Large Hadron Collider (LHC) energies. Jets are reconstructed with anti-k T algorithm in the pseudorapidity range $|{\eta }_{\mathrm{jet}}|<2.1$ for resolution parameter R= 0.2, 0.3 and 0.4. For background subtraction, a Jewel-compatible 4-Momenta subtraction technique (4MomSub) have been used. The modification of inclusive jet-yields in Pb-Pb collisions relative to proton-proton interactions, quantified by $R_{AA}^{\mathrm{jet}}$, are seen to be in reasonable agreement with ALICE, ATLAS and CMS data over a broad transverse momentum range. Jewel is able to capture the qualitative features of the modifications to the fragmentation functions and radial momentum distributions in data but not always quantitatively. This quantitative discrepancy may be related to the simplified treatment of recoil partons in the background model and partly due to background subtraction procedure itself. Nevertheless, observed modification of jet shape variables in Jewel corroborates the fact that in-medium fragmentation is harder and more collimated than the fragmentation in vacuum. We further observe that these modifications depend on the transverse momentum of jets and it seems that medium resolves the core structure of low momentum jets below 100 GeV/c at LHC energies.

References in corpus (10)

• Measurements of the Nuclear Modification Factor for Jets in Pb+Pb Collisions at $\sqrt{s_{\mathrm{NN}}}=2.76$ TeV with the ATLAS Detector
• Radiative and Collisional Jet Energy Loss in the Quark-Gluon Plasma at RHIC
• Jet physics in heavy-ion collisions
• Measurement of jet suppression in central Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 2.76 TeV
• Medium response in JEWEL and its impact on jet shape observables in heavy ion collisions
• Parton shower evolution in a 3-d hydrodynamical medium
• Collision Energy Dependence of Viscous Hydrodynamic Flow in Relativistic Heavy-Ion Collisions
• Resolving the plasma profile via differential single inclusive suppression
• The theory and phenomenology of jets in nuclear collisions
• Inclusive jet measurements in pp and Pb-Pb collisions with ALICE

Cited by in corpus (3)

• Impact of scale, nuclear PDF and temperature variations on the interpretation of medium-modified jet production data from the LHC
• Study of medium modified jet shape observables in Pb-Pb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV using EPOS and JEWEL event generators
• Medium modification of jet shape observables in Pb-Pb collisions at $\sqrt{s_{NN}}$= 2.76 TeV using EPOS and JEWEL event generators