Optimization and calibration of the same-side kaon tagging algorithm using hadronic B0s decays in 2011 data

Abstract

We report on the optimization and calibration of the same-side kaon tagging algorithm using the decay B0s→D−π+s with 1.0~fb−1 of data from the LHCb 2011 physics run. After a data-driven optimization and calibration, we measured an effective tagging efficiency for the same-side tagger of (1.5±0.4) using event-by-event predicted mistag for B0s→D−π+s decays. For the combination of same-side kaon and opposite-side taggers the corresponding effective tagging efficiency is (3.8±0.7) using event-by-event predicted mistag in this channel.