Non-factorizable contributions to B[sub d][sup 0] → D[sub s][sup (∗)]D[sub s][sup (∗)] from chiral loops and tree level 1/Nc terms

Abstract

Abstract.We point out that the amplitudes for the decaysIf one or two of the D-mesons in the final state are vectors (i.e D * 's) there are relatively small factorizable contributions through the annihilation mechanism. The dominant contributions to the decay amplitudes arise from chiral loop contributions and 1/N c suppressed tree level. We predict that the branching ratios for the processesBare of order (4 − 7) × 10 −3 . If both D-mesons in the final state are D * 's, we obtain branching ratios of order two times bigger.

First observations ofB¯s0→D+D−,DAaij1, Beteta2, Adeva3 et al. 2013Phys. Rev. D260110View full textAdd to dashboardCite

“…Predictions of the " B 0 s ! D þ D À branching fraction using perturbative approaches yield $5:0 Â 10 À4 [21], while the use of nonperturbative approaches has led to a larger value of 4:5 Â 10 À3 [22]. More recent phenomenological studies, which assume a dominant contribution from rescattering, predict a significantly lower branching fraction of Bð " B 0…”