1210.6486 (ATLAS Collaboration)

Measurement of Z boson Production in Pb+Pb Collisions at sqrt(s_NN)=2.76
TeV with the ATLAS Detector    [PDF]

ATLAS Collaboration

The ATLAS experiment has observed 1995 Z boson candidates in data corresponding to 0.15 inverse nb of integrated luminosity obtained in the 2011 LHC Pb+Pb run at sqrt(s_NN)=2.76 TeV. The Z bosons are reconstructed via di-electron and di-muon decay channels, with a background contamination of less than 3%. Results from the two channels are consistent and are combined. Within the statistical and systematic uncertainties, the per-event Z boson yield is proportional to the number of binary collisions estimated by the Glauber model. The elliptic anisotropy of the azimuthal distribution of the Z boson with respect to the event plane is found to be consistent with zero.

View original: http://arxiv.org/abs/1210.6486