Study of Z Production in PbPb and Pp Collisions at [arrow]"NN
Author | : |
Publisher | : |
Total Pages | : |
Release | : 2015 |
ISBN-10 | : OCLC:925455073 |
ISBN-13 | : |
Rating | : 4/5 (73 Downloads) |
Book excerpt: The production of Z bosons is studied in the dimuon and dielectron decay channels in PbPb and pp collisions at [arrow]"NN = 2.76 TeV, using data collected by the CMS experiment at the LHC. The PbPb data sample corresponds to an integrated luminosity of about 166 [mu]b-1, while the pp data sample collected in 2013 at the same nucleon-nucleon centre-of-mass energy has an integrated luminosity of 5.4 pb-1. The Z boson yield is measured as a function of rapidity, transverse momentum, and collision centrality. The ratio of PbPb to pp yields, scaled by the number of inelastic nucleon-nucleon collisions, is found to be 1.06 " 0.05 (stat) " 0.08 (syst) in the dimuon channel and 1.02 " 0.08 (stat) " 0.15 (syst) in the dielectron channel, for centrality-integrated Z boson production. This binary collision scaling is seen to hold in the entire kinematic region studied, as expected for a colourless probe that is unaffected by the hot and dense QCD medium produced in heavy ion collisions.