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arXiv · 0808.3509

Heavy-to-heavy quark decays at NNLO

Alexey Pak·Andrzej Czarnecki
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Abstract

Details of a recent calculation of O(alpha_s^2) corrections to the decay b -> c,l,nu_l, taking into account the c-quark mass, are described. Construction of the expansion in the mass ratio m_c/m_b as well as the evaluation of new four-loop master integrals are presented. The same techniques are applicable to the muon decay, mu -> e,nu_mu,anti-nu_e. Analytical results are presented, for the physical cases as well as for a model with purely-vector couplings.

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Alexey Pak, Andrzej Czarnecki. 2008-08-26. Heavy-to-heavy quark decays at NNLO. https://doi.org/10.1103/physrevd.78.114015

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