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Improved Constraints on $B \to π\ell \barν_{\ell}$ Form Factors

Damir Becirevic
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Abstract

The behavior of the $\bpi$ form factors in the entire physical range is examined in a model independent way. Unitarity bounds are further constrained by the lattice results (APE). From this analysis, we obtain $f^{+}(0) = 0.38 \pm .03$ if the $B^{*}$-pole dominance behavior is assumed. However, to get the information on the behavior of the form factor $f^{+}$, QSR results are included. We see the deviations from the pole dominance due to the contributions of the higher singularities which are to be treated with more precise lattice data.

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Damir Becirevic. 1996-03-13. Improved Constraints on $B \to π\ell \barν_{\ell}$ Form Factors. https://arxiv.org/abs/hep-ph/9603298

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