6533b860fe1ef96bd12c2d15

RESEARCH PRODUCT

Measurement of angular correlations in Drell-Yan lepton pairs to probe Z/gamma* boson transverse momentum at root s=7 TeV with the ATLAS detector

Atlas CollaborationSusana Cabrera UrbánMaría Victoria Castillo GiménezMaría José Costa MezquitaFarida FassiAntonio Ferrer SoriaLuca FioriniJuan A. Fuster VerdúCarmen García GarcíaJosé Enrique García NavarroSantiago González De La HozYesenia Hernández JiménezEmilio Higón RodríguezAdrián Irles QuilesMohammed KaciCarlos Lacasta LlácerVicente Lacuesta MiquelLuis March RuizSalvador Martí GarcíaMercedes Miñano MoyaVasiliki MitsouRegina Moles VallsMaría Moreno LlácerElena Oliver GarcíaSebastián Pedraza LópezMaría Teresa Pérez García-estañE. Romero AdamEduardo Ros MartínezJosé Salt CairolsVictoria Sánchez MartínezU. SoldevilaJavier Sánchez MartínezEmma Torró PastorAlberto Valero BiotE. Valladolid GallegoJuan Antonio Valls FerrerMiguel Villaplana PérezMarcel Vos

subject

High Energy Physics::PhenomenologyHigh Energy Physics::ExperimentFísica nuclear

description

A measurement of angular correlations in Drell-Yan lepton pairs via the phistar observable is presented. This variable probes the same physics as the Z/gamma* boson transverse momentum with a better experimental resolution. The Z/gamma*->e+e- and Z/gamma*->mu+mu- decays produced in proton--proton collisions at a centre-of-mass energy of sqrt(s) = 7 TeV are used. The data were collected with the ATLAS detector at the LHC and correspond to an integrated luminosity of 4.6 fb-1. Normalised differential cross sections as a function of phistar are measured separately for electron and muon decay channels. These channels are then combined for improved accuracy. The cross section is also measured double differentially as a function of phistar for three independent bins of the Z boson rapidity. The results are compared to QCD calculations and to predictions from different Monte Carlo event generators. The data are reasonably well described, in all measured Z boson rapidity regions, by resummed QCD predictions combined with fixed-order perturbative QCD calculations. Some of the Monte Carlo event generators are also able to describe the data. The measurement precision is typically better by one order of magnitude than present theoretical uncertainties.

yearjournalcountryeditionlanguage
2013-01-01
10.1016/j.physletb.2013.01.054http://hdl.handle.net/10550/37933