Modification of jet shapes in PbPb collisions at root s(NN)=2.76 TeV


Chatrchyan S., Khachatryan V., Sirunyan A. M., Tumasyan A., Adam W., Bergauer T., ...More

PHYSICS LETTERS B, vol.730, pp.243-263, 2014 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 730
  • Publication Date: 2014
  • Doi Number: 10.1016/j.physletb.2014.01.042
  • Journal Name: PHYSICS LETTERS B
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.243-263
  • Keywords: CMS, Heavy ion physics, Jet shapes, LARGE TRANSVERSE-MOMENTUM, CENTRAL AU+AU COLLISIONS, QUARK-GLUON PLASMA, SUPPRESSION, PERSPECTIVE
  • Çukurova University Affiliated: Yes

Abstract

The first measurement of jet shapes, defined as the fractional transverse momentum radial distribution, for inclusive jets produced in heavy-ion collisions is presented. Data samples of PbPb and pp collisions, corresponding to integrated luminosities of 150 mu b(-1) and 5.3 pb(-1) respectively, were collected at a nucleon-nucleon centre-of-mass energy of root s(NN) = 2.76 TeV with the CMS detector at the LHC. The jets are reconstructed with the anti-k(T) algorithm with a distance parameter R = 0.3, and the jet shapes are measured for charged particles with transverse momentum P-T > 1 GeV/c. The jet shapes measured in PbPb collisions in different collision centralities are compared to reference distributions based on the pp data. A centrality-dependent modification of the jet shapes is observed in the more central PbPb collisions, indicating a redistribution of the energy inside the jet cone. This measurement provides information about the parton shower mechanism in the hot and dense medium produced in heavy-ion collisions. (C) 2014 The Authors. Published by Elsevier B.V.