Radiative and semi-leptonic B-meson decay spectra: Sudakov resummation beyond logarithmic accuracy and the pole mass

Abstract

The inclusive spectra of radiative and semi-leptonic B-meson decays near the endpoint is computed taking into account renormalons in the Sudakov exponent (Dressed Gluon Exponentiation). In this framework we demonstrate the factorization of decay spectra into hard, jet and soft functions and discuss the universality of the latter two. Going beyond perturbation theory the soft function, which we identify as the longitudinal momentum distribution in an on-shell b quark, is replaced by the b-quark distribution in the B meson. The two differ by power corrections. We show how the resummation of running-coupling effects can be used to perform consistent separation to power accuracy between perturbative and non-perturbative contributions. In particular, we prove that the leading infrared renormalon ambiguity in the Sudakov exponent cancels against the one associated with the definition of the pole mass. This cancellation allows us to identify the non-perturbative parameter that controls the shift of the perturbative spectrum in the heavy-quark limit as the mass difference between the meson and the quark.

to appear in JHEP; small changes, some refs. added; 36 pages, 2 ps figures

Cited by in corpus (17)

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• Theory of Charmless Inclusive B Decays and the Extraction of V_{ub}
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• Inclusive spectra in charmless semileptonic B decays by Dressed Gluon Exponentiation
• Measurements of the B -> X_s gamma Branching Fraction and Photon Spectrum from a Sum of Exclusive Final States
• Factorization for Power Corrections to B->Xs gamma and B-> Xu e nu
• Inclusive Measure of |V_ub| with the Analytic Coupling Model
• On the quark distribution in an on-shell heavy quark and its all-order relations with the perturbative fragmentation function
• Radiative B decay spectrum: DGE at NNLO
• The asymptotic behavior of the heavy quark form factors at higher order
• B Meson Decays
• Taming the B --> X(s) gamma spectrum by Dressed Gluon Exponentiation
• A dispersive approach to Sudakov resummation
• Running-coupling effects in the triple-differential charmless semileptonic decay width
• Progress in computing inclusive B decay spectra
• Vub extraction using the Analytic Coupling model
• High order perturbative corrections to the determination of |Vub| from the P+ spectrum in B -> Xu l nu