ISSN - 15507998, Physical Review D - Particles, Fields, Gravitation and Cosmology, 2005, vol. 73, p. -
Search for rare quark-annihilation decays, B-→Ds
We report on searches for B-→Ds- and B-→Ds*-. In the context of the standard model, these decays are expected to be highly suppressed since they proceed through annihilation of the b and ū quarks in the B- meson. Our results are based on 234×106 Υ(4S)→BB̄ decays collected with the BABAR detector at SLAC. We find no evidence for these decays, and we set Bayesian 90% confidence level upper limits on the branching fractions B(B-→Ds-)<1.9×10-6 and B(B-→Ds*-)<1. 2×10-5. These results are consistent with standard model expectations. © 2006 The American Physical Society.