Form factors for the semileptonic decay B → πℓν

Abstract

Previously published determinations for B → πℓν form factors are fit using a parameterization proposed by Becirevic and Kaidalov which incorporates physical constraints on the form factors. We check the consistency of the extrapolation to p π = 0 by testing phenomenological expectations in the combined chiral and heavy quark limits. We then examine how well current lattice results constrain the form factors in extrapolations to the maximum pion recoil limit.