Measurement of the D s+-D s- production asymmetry in 7 TeV pp collisions

Abstract

Heavy quark production in 7 TeV centre-of-mass energy pp collisions at the LHC is not necessarily flavour symmetric. The production asymmetry, A P, between Ds+ and Ds- mesons is studied using the φπ ± decay mode in a data sample of 1.0fb -1 collected with the LHCb detector. The difference between π + and π - detection efficiencies is determined using the ratios of fully reconstructed to partially reconstructed D ± decays. The overall production asymmetry in the Ds± rapidity region 2.0 to 4.5 with transverse momentum larger than 2 GeV is measured to be A P=(-0.33±0.22±0.10)%. This result can constrain models of heavy flavour production. © 2012 CERN.