Measurement of the {bar B} {yields} D{ell}{bar {nu}} Anti-Neutrino Partial Width and Form Factor Parameters

Abstract

We have studied the decay {bar B} {yields} D{ell}{bar {nu}}, where {ell} = e or {mu}. From a fit to the differential decay rate d{Lambda}/dw we measure the rate normalization F{sub D}(1)|V{sub cb}| and form factor slope {rho}{sub D}{sup 2}, and, using measured values of {tau}{sub B}, find {Lambda}({bar B} {yields} D{ell}{bar {nu}}) = (12.0 {+-} 0.9 {+-} 2.1) ns{sup -1}. The resulting branching fractions are {Beta}({bar B}{sup 0} {yields} D{sup +}{ell}{sup -}{bar {nu}}) = (1.87 {+-} 0.15 {+-} 0.32)% and {Beta}(B{sup -} {yields} D{sup 0}{ell}{sup -}{bar {nu}}) = (1.94 {+-} 0.15 {+-} 0.34)%. The form factor parameters are in agreement with those measured in {bar B} {yields} D*{ell}{bar {nu}} decays, as predicted by heavy quark effective theory.