Measurement of the cross-section for Z → e⁺e^- production in pp collisions at √s = 7 TeV

A measurement of the cross-section for pp → Z → e ⁺e ^- is presented using data at √s = 7 TeV corresponding to an integrated luminosity of 0.94 fb ^-1. The process is measured within the kinematic acceptance p _T > 20 GeV=c and 2 < η < 4:5 for the daughter electrons and dielectron invariant mass in the range 60-120 GeV=c ². The cross-section is determined to be σ(pp → Z → e ⁺e ^-) = 76:0 ± 0:8 ± 2:0 ± 2:6 pb where the first uncertainty is statistical, the second is systematic and the third is the uncertainty in the luminosity. The measurement is performed as a function of Z rapidity and as a function of an angular variable which is closely related to the Z transverse momentum. The results are compared with previous LHCb measurements and with theoretical predictions from QCD. Copyright CERN.