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arXiv · hep-ph/9504235

Model-Independent Extraction of |V_{cb}| Using Dispersion Relations

C. Glenn Boyd·Benjamin Grinstein·Richard F. 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 νform factors, and extract |V_{cb}|=0.037^{+0.003}_{-0.002} 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. The method also allows a description of B -> D l nu form factors accurate to 1% in terms of two parameters.

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C. Glenn Boyd, Benjamin Grinstein, Richard F. Lebed. 1995-04-06. Model-Independent Extraction of |V_{cb}| Using Dispersion Relations. https://doi.org/10.1016/0370-2693(95)00480-9

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