ISSN - 15507998, Physical Review D - Particles, Fields, Gravitation and Cosmology, 2007, vol. 75, p. -
Improved measurement of B̄0→Ds-D+ and search for B̄0→Ds+Ds- at Belle
We reconstruct B̄0→Ds-D+ decays using a sample of 449×106 BB̄ pairs recorded by the Belle experiment, and measure the branching fraction to be B(B̄0→Ds-D+)=[7.5±0.2(stat)±0.8(syst) ±0.8(B′s)]×10-3. A search for the related decay B̄0→Ds+Ds- is also performed. Since we observe no statistically significant signal, an upper limit on the branching fraction is set at 3.6×10-5 (90% C.L.). © 2007 The American Physical Society.