Ms Sevda Esen (University of Cincinnati)
The large data sample being recorded with the Belle detector at the Y(5S) energy provides a unique opportunity to study the poorly-known Bs meson decays. Following our recent measurement of Bs->Ds π in a sample of 23.6 fb-1, we extend the analysis to include decays with photons in the final state. Using the same sample, we report the first observation of three other dominant exclusive Bs decays, in the modes Bs->Ds-* π+, Bs->Ds- ρ+ and Bs->Ds-* ρ+. We measure their respective branching fractions and, using helicity-angle distributions, the longitudinal polarization fraction of the Bs->Ds-* ρ+ decay. We also present a measurement of the branching fractions for the decays Bs->Ds+* Ds-*. In the heavy quark limit, this branching fraction is directly related to the width difference between the CP-odd and CP-even Bs states.
Dr Karim TRABELSI (KEK)