Measurement of the B¯0–B0 and B¯s0–Bs0 production asymmetries in pp collisions at s=7 TeV

The B¯0–B0 and B¯s0–Bs0 production asymmetries, AP(B0) and AP(Bs0) , are measured by means of a time-dependent analysis of B0→J/ψK⁎0 , B0→D−π+ and Bs0→Ds−π+ decays, using a data sample corresponding to an integrated luminosity of 1.0 fb−1 , collected by LHCb in pp collisions at a centre-of-mass energy of 7 TeV . The measurements are performed as a function of transverse momentum and pseudorapidity of the B0 and Bs0 mesons within the LHCb acceptance. The production asymmetries, integrated over pT and η in the range 4<pT<30 GeV/c and 2.5<η<4.5 , are determined to be AP(B0)=(−0.35±0.76±0.28)% and AP(Bs0)=(1.09±2.61±0.66)% , where the first uncertainties are statistical and the second systematic.