Towards a global fit to extract the B->Xs gamma decay rate and Vub

Abstract

© Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike Licence. The total B → Xsγ decay rate and the CKM-matrix element |Vub| play an important role in finding indirect evidence for new physics affecting the flavor sector of the Standard Model, complementary to direct searches at the LHC and Tevatron. Their determination from inclusive B-meson decays requires the precise knowledge of the parton distribution function of the b quark in the B meson, called the shape function. We implement a new model-independent framework for the shape function with reliable uncertainties based on an expansion in a suitable set of basis functions. We present the current status of a global fit to BABAR and Belle data to extract the shape function and the B → Xsγ decay rate.