Measurement of the CP Asymmetry in B+→K+μ+μ− Decays

Abstract

A measurement of the C P asymmetry in B + → K + μ + μ − decays is presented using p p collision data, corresponding to an integrated luminosity of 1.0 fb − 1 , recorded by the LHCb experiment during 2011 at a center-of-mass energy of 7 TeV. The measurement is performed in seven bins of μ + μ − invariant mass squared in the range 0.05 < q 2 < 22.00 GeV 2 / c 4 , excluding the J / ψ and ψ ( 2 S ) resonance regions. Production and detection asymmetries are corrected for using the B + → J / ψ K + decay as a control mode. Averaged over all the bins, the C P asymmetry is found to be A C P = 0.000 ± 0.033 ( stat ) ± 0.005 ( syst ) ± 0.007 ( J / ψ K ), where the third uncertainty is due to the C P asymmetry of the control mode. This is consistent with the standard model prediction.