QCD BASIS FOR FACTORIZATION IN DECAYS OF HEAVY MESONS

The amplitudes for nonleptonic decays of heavy mesons are notoriously difficult to calculate. Factorization has been used in an attempt to transcribe results from model calculations of semileptonic decay rates of heavy mesons. We propose that factorization holds perturbatively in QCD, provided one looks in the appropriate kinematic regime. This is studied with the use of a novel expansion in which factorization holds in leading order, which includes all orders in the loop expansion. Our results are contrasted with large-N expansion arguments.