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A Comment on the Extractions of V_{ub} from Radiative Decays

Adam K. Leibovich·Ian Low·I. Z. Rothstein
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Abstract

We present a model independent closed form expression for |V_{ub}|^2/|V_{tb} V_{ts}^*|^2, which includes the resummation of large endpoint logarithms as well as the interference effects from the operators $O_2$ and $O_8$. We demonstrate that the method to extract |V_{ub}| presented by the authors in hep-ph/9909404, and modified in this letter to include interference effects, is not just a refinement of the method introduced in hep-ph/9312311. We also discuss the model dependence of the latter proposal. Furthermore, we show that the resummation is not negligible and that the Landau pole does not introduce any significant uncertainties.

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Adam K. Leibovich, Ian Low, I. Z. Rothstein. 2001-05-10. A Comment on the Extractions of V_{ub} from Radiative Decays. https://doi.org/10.1016/s0370-2693(01)00667-0

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