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arXiv · 1303.0958

A model independent determination of the B -> Xs gamma decay rate

Florian U. Bernlochner·Heiko Lacker·Zoltan Ligeti·Iain W. Stewart·Frank J. Tackmann·Kerstin Tackmann
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Abstract

The goal of the SIMBA collaboration is to provide a global fit to the available measurements of inclusive B -> X_s gamma and B -> X_u l nu decays. By performing a global fit one is able to simultaneously determine the relevant normalizations, i.e. the total B -> X_s gamma rate and the CKM-matrix element |Vub|, together with the required hadronic parameters, most importantly the b-quark mass and the b-quark distribution function in the B-meson, called the shape function. In this talk, the current status on the model-independent determination of the shape function and |C7^\incl Vtb Vts*|, which parametrizes the total B -> Xs gamma rate, from a global fit to the available B -> X_s gamma measurements from Babar and Belle is presented. In particular, the theoretical uncertainties originating from variations of the different factorization scales are evaluated.

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Florian U. Bernlochner, Heiko Lacker, Zoltan Ligeti, Iain W. Stewart, Frank J. Tackmann, Kerstin Tackmann. 2013-03-05. A model independent determination of the B -> Xs gamma decay rate. https://arxiv.org/abs/1303.0958

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