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Model-Independent Semileptonic Form Factors Using Dispersion Relations

C. G. Boyd·B. Grinstein·R. Lebed
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Abstract

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 B -> D* l nu form factors, and extract |V_cb|=0.0355^{+0.0029}_{-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.

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C. G. Boyd, B. Grinstein, R. Lebed. 1995-08-29. Model-Independent Semileptonic Form Factors Using Dispersion Relations. https://doi.org/10.1007/bf02823628

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