Determination of fs/fd for 7 TeV pp Collisions and Measurement of the B0→D−K+ Branching Fraction

Abstract

The relative abundance of the three decay modes B0→D−K+, B0→D−π+, and B0s→D−sπ+ produced in 7 TeV pp collisions at the LHC is determined from data corresponding to an integrated luminosity of 35 pb−1. The branching fraction of B0→D−K+ is found to be B(B0→D−K+)=(2.01±0.18stat±0.14syst)×10−4. The ratio of fragmentation fractions fs/fd is determined through the relative abundance of B0s→D−sπ+ to B0→D−K+ and B0→D−π+, leading to fs/fd=0.253±0.017±0.017±0.020, where the uncertainties are statistical, systematic, and theoretical, respectively.