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arXiv · hep-ph/9702300

Analyticity, Shapes of Semileptonic Form Factors, and B to pi l nu

C. Glenn Boyd·Martin J. Savage
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Abstract

We give a pedagogical discussion of the physics underlying dispersion relation-derived parameterizations of form factors describing B -> pi l nu and B -> D l nu. Moments of the dispersion relations are shown to provide substantially tighter constraints on the f_+ (t) form factor describing B -> pi l nu than the unweighted dispersion relation alone. Heavy quark spin symmetry relations between the B -> pi l nu and B^* -> pi l nu form factors enables such constraints to be tightened even further.

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C. Glenn Boyd, Martin J. Savage. 1997-02-11. Analyticity, Shapes of Semileptonic Form Factors, and B to pi l nu. https://doi.org/10.1103/physrevd.56.303

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