Unravelling Soft Components in the Shape Function for Inclusive B Decays
نویسندگان
چکیده
منابع مشابه
Unravelling soft components in the shape function for inclusive B decays
In the heavy-quark limit, the decay spectrum in radiative and semileptonic inclusive B-meson decays is determined by a universal structure function, i.e. the shape function. We study the constraints on the bilocal heavy-quark operator for the shape function from the QCD equations of motion and heavy-quark symmetry, and obtain a new basis of nonlocal operators that reveal relevant soft component...
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Inclusive B-meson decays, such as semileptonic B → Xulν̄ decays and penguininduced B → Xsγ decays, are of special interest because they are sensitive probes of electroweak parameters as well as new physics. Especially for the precise determination of the CKM matrix element |Vub|, the region near the kinematic endpoint for the lepton energy spectrum, El ∼ E max l = mB/2, in the decay B → Xulν̄ pla...
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The contributions of subleading shape functions to inclusive decay distributions of B mesons are derived from a systematic two-step matching of QCD current correlators onto soft-collinear and heavy-quark effective theory. At tree-level, the results can be expressed in terms of forward matrix elements of bi-local light-cone operators. Fourquark operators, which arise at O(αs), are included. Our ...
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We discuss the non-perturbative and the radiative corrections to inclusive B decays from the point of view known from QED corrections to high energy ee processes. Here the leading contributions can be implemented through the so called “radiator function” which corresponds to the shape function known in heavy hadron decays. In this way some new insight into the origin of the shape function is ob...
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We compute 2-loop QCD corrections to the hard coefficient functions which arise in the factorization formula for B → Xulν decays in the shape-function region. Our calculation provides the last missing piece required for a NNLO analysis of inclusive semileptonic B decays, which may significantly reduce the theoretical uncertainty in the extraction of the CKM matrix element |Vub|. Among the techn...
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ژورنال
عنوان ژورنال: Progress of Theoretical Physics
سال: 2005
ISSN: 0033-068X,1347-4081
DOI: 10.1143/ptp.113.183