Theoretical Analysis of B -> D^{**} pi Decays

Abstract

The decays B -> D^{**} pi, where D^{**} is a narrow p-wave charm resonance, are investigated in the context of a generalized factorization hypothesis, including the leading nonfactorizable corrections. The decay rates for these processes are related to the corresponding semileptonic rates at maximum recoil. It is pointed out that the current data on the branching ratio for the decay B^- -> D_2^{*0} pi^- may pose a problem for theory. We predict that future, more accurate measurements of this branching ratio will find a value B(B^- -> D_2^{*0} pi^-) = 4 * 10^{-4}, a factor 5 lower than the current central value.