v 2 2 9 A ug 1 99 5 UCSD / PTH 95 - 15 Model - Independent Semileptonic Form Factors Using Dispersion Relations §
نویسنده
چکیده
We present a method for parametrizing heavy meson semileptonic form factors using dispersion relations, and from it produce a two-parameter description of the B → B elastic form factor. We use heavy quark symmetry to relate this function to B̄ → Dlν̄ form factors, and extract |Vcb| = 0.0355 −0.0025 from experimental data with a least squares fit. Our method eliminates model-dependent uncertainties inherent in choosing a parametrization for the extrapolation of the differential decay rate to threshold.
منابع مشابه
ar X iv : h ep - p h / 95 08 24 5 v 1 5 A ug 1 99 5 UCSD / PTH 95 - 07 June 1995 EFFECTIVE FIELD THEORIES
These lectures introduce some of the basic notions of effective field theories, as used in particle physics. The topics discussed are the ∆S = 1 and ∆S = 2 weak interactions, and chiral perturbation theory as applied to mesons, baryons, and hadrons containing heavy quarks.
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