Nonfactorizable contribution to B-d(0) -> pi D-0(0)

作者：Leganger Lars E^*; Eeg Jan O

来源：Physical Review D - Particles, Fields, Gravitation and Cosmology, 2010, 82(7): 074007.

DOI：10.1103/PhysRevD.82.074007

The decay modes of the type B -> pi D are dynamically different. For the case B-d(0) -> pi D--(+) there is a substantial factorized contribution which dominates. In contrast, the decay mode B-d(0) -> pi D-0(0) has a small factorized contribution, being proportional to a very small Wilson coefficient combination. In this paper we calculate the relevant Wilson coefficients at one loop level in the heavy quark limits, both for the b quark and the c quark. We also emphasize that for the decay mode B-d(0) -> pi D-0(0) there is a sizeable nonfactorizable contribution due to long-distance interactions, which dominate the amplitude. We estimate the branching ratio for this decay mode within our framework, which uses the heavy quark limits, both for the b and the c quarks. In addition, we treat energetic light (u, d, s) quarks within a variant of large energy effective theory and combine this with a new extension of chiral quark models in order to estimate the effect of soft-gluon emission. For reasonable values of the model-dependent parameters of our model, we can account for at least 3/4 of the amplitude needed to explain the experimental branching ratio similar or equal to 2.6 x 10(-4).

• 出版日期2010-10-5