Factorization in leptonic radiative B→γeν decays Original Research Article

We discuss factorization in exclusive radiative leptonic B→γeν̄ decays using the soft-collinear effective theory. The form factors describing these decays can be expanded in a power series in ΛQCD/Eγ with Eγ the photon energy. We write down the most general operators in the effective theory which contribute to the form factors at leading order in ΛQCD/Eγ, proving their factorization into hard, jet and soft contributions, to all orders in αs.