PNNL

Abstract

We report measurements of branching fractions and time-dependent CP asymmetries in B0?D+D- and B0?D*±D± decays using a data sample that contains (772±11)×106BB¯ pairs collected at the ?(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. We determine the branching fractions to be B(B0?D+D-)=(2.12±0.16±0.18)×10-4 and B(B0?D*±D±)=(6.14±0.29±0.50)×10-4. We measure CP asymmetry parameters SD+D-=-1.06-0.14+0.21±0.08 and CD+D-=-0.43±0.16±0.05 in B0?D+D- and AD*D=+0.06±0.05±0.02, SD*D=-0.78±0.15±0.05, CD*D=-0.01±0.11±0.04, ?SD*D=-0.13±0.15±0.04 and ?CD*D=+0.12±0.11±0.03 in B0?D*±D±, where the first uncertainty is statistical and the second is systematic. We exclude the conservation of CP symmetry in both decays at equal to or greater than 4s significance.