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arXiv · hep-ph/9909404

Extracting V_{ub} Without Recourse to Structure Functions

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

We present a closed form expression for |V_{ub}|^2/ |V_{tb} V_{ts}^*|^2 in terms of the endpoint photon and lepton spectra from the inclusive decays B -> X_sγand B -> X_u\ellν, respectively, which includes the resummation of the endpoint logs at next to leading order and is completely independent of the B meson structure function. The use of this expression for extracting V_{ub} would eliminate the large systematic errors usually incurred due to the modeling of the heavy quarks' Fermi motion.

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Adam K. Leibovich, Ian Low, I. Z. Rothstein. 1999-12-21. Extracting V_{ub} Without Recourse to Structure Functions. https://doi.org/10.1103/physrevd.61.053006

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