Impact of four-quark shape functions on inclusive B decay spectra
نویسندگان
چکیده
منابع مشابه
Impact of Four-Quark Shape Functions on Inclusive B Decay Spectra
It has recently been pointed out that a new class of subleading shape functions involving B-meson matrix elements of non-local four-quark operators contributes at order ΛQCD/mb to B̄ → Xu l ν̄ decay distributions in the endpoint region. The corresponding functions fu(ω) and fv(ω) are estimated using the vacuum-insertion approximation. A numerical analysis of various B̄ → Xu l ν̄ decay spectra sugge...
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A leading-power factorization formula for weight functions relating the B̄ → Xsγ photon spectrum to arbitrary partial decay rates in B̄ → Xu lν̄ is derived. These weight functions are independent of the hadronic shape function and allow for the determination of |Vub| in a model-independent way. We calculate the weight function in renormalizationgroup improved perturbation theory to complete next-t...
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ژورنال
عنوان ژورنال: The European Physical Journal C
سال: 2005
ISSN: 1434-6044,1434-6052
DOI: 10.1140/epjc/s2005-02360-4