First observations of B̄s0→D+D-, Ds+D- and D0D̄0 decays

Abstract

First observations and measurements of the branching fractions of the B̄s0→D+D-, B̄s0→Ds+D- and B̄s0→D0D̄0 decays are presented using 1.0 fb -1 of data collected by the LHCb experiment. These branching fractions are normalized to those of B̄0→D +D-, B0→D-Ds+ and B-→D0Ds- , respectively. An excess of events consistent with the decay B ̄0→D0D̄0 is also seen, and its branching fraction is measured relative to that of B-→D0Ds-. Improved measurements of the branching fractions B(B̄s0→Ds+Ds-) and B(B -→D0Ds-) are reported, each relative to B(B0→D -Ds+). The ratios of branching fractions are B(B̄s0→D +D-)B(B̄0→D+D -)=1.08±0.20±0.10, B(B̄s0→Ds+D -)B(B0→D-Ds+)=0.050±0.008±0.004, B(B̄s0→D0D̄0)B(B-→D0Ds-)=0. 019±0.003±0.003, B(B̄0→D0D ̄0)B(B-→D0Ds-)<0.0024 at 90% CL, B(B̄s0→Ds+Ds-)B(B0→D-Ds+)=0.56±0.03±0. 04, B(B-→D0Ds-)B(B0→D-Ds+)=1.22±0. 02±0.07, where the uncertainties are statistical and systematic, respectively. © 2013 CERN.