We present non-perturbative, model-independent parametrizations of the individual QCD form factors relevant to B̄ → D*lv̄ and B̄ → Dlv̄ decays. These results follow from dispersion relations and analyticity, without recourse to heavy quark symmetry. To describe a form factor with two percent accuracy, three parameters are necessary, one of which is its normalization at zero recoil, ℱ(1). We combine the individual form factors using heavy quark symmetry to extract values for the product |Vcb|ℱ(1) from B̄ → D*lv̄ data with negligible extrapolation uncertainty.
ASJC Scopus subject areas
- Nuclear and High Energy Physics