Summary: Measurement of the rapidity and transverse momentum distributions of Z bosons
in pp collisions at
ffiffi
ð
p
sÞ¼7 TeV
S. Chatrchyan et al.*
(CMS Collaboration)
(Received 23 October 2011; published 7 February 2012)
Measurements of the normalized rapidity (y) and transverse-momentum (qT) distributions of Drell­Yan
muon and electron pairs in the Z-boson mass region (60 < M`` < 120 GeV) are reported. The results are
obtained using a data sample of proton-proton collisions at a center-of-mass energy of 7 TeV, collected by
the CMS experiment at the Large Hadron Collider (LHC), corresponding to an integrated luminosity of
36 pbÀ1. The distributions are measured over the ranges jyj < 3:5 and qT < 600 GeV and compared with
quantum chromodynamics (QCD) calculations using recent parton distribution functions to model the
momenta of the quarks and gluons in the protons. Overall agreement is observed between the models and
data for the rapidity distribution, while no single model describes the Z transverse-momentum distribution
over the full range.
DOI: 10.1103/PhysRevD.85.032002 PACS numbers: 13.60.Hb, 13.38.Dg, 13.85.Qk
I. INTRODUCTION

Source: Adolphs, Ralph - Psychology and Neuroscience, California Institute of Technology

Collections: Biology and Medicine