Study of Z boson production in PbPb collisions at √sNN=2.76  TeV

Abstract

A search for Z bosons in the μ+μ- decay channel has been performed in PbPb collisions at √sNN=2.76  TeV with the CMS detector at the LHC, in a 7.2  μb-1 data sample. The number of opposite-sign muon pairs observed in the 60–120  GeV/c2 invariant mass range is 39, corresponding to a yield per unit of rapidity (y) and per minimum bias event of [33.8±5.5(stat)±4.4(syst)]×10-8, in the |y|<2.0 range. Rapidity, transverse momentum, and centrality dependencies are also measured. The results agree with next-to-leading order QCD calculations, scaled by the number of incoherent nucleon-nucleon collisions. Published by the American Physical Society under the terms of the Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. © 2011 CERN, for the CMS Collaboration