Study of jet quenching using photon-jet events in PbPb collisions at 2.76 TeV with CMS

[摘要] The first measurement of the transverse momentum (p[subscript T]) imbalance of isolated–photon + jet pairs in relativistic heavy ion collisions is reported. The analysis uses data from PbPb collisions at a centre-of-mass energy of 2.76 TeV per nucleon pair, corresponding to an integrated luminosity of 150μb[superscript −1] recorded by the CMS experiment at the LHC in 2011. For events containing an isolated photon with transverse momentum p[subscript T] > 60GeV/c and an associated jet with p[subscript T] > 30GeV/c, the photon + jet p[subscript T] imbalance is studied as a function of collision centrality and compared to pp data and pythia calculations at the same centre-of-mass energy. Using the p[subscript T] of the isolated photon as an estimate of the energy of the scattered parton, this measurement allows an unbiased characterization of the in-medium parton energy loss.

[发布机构] Elsevier