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Heavy-to-light decays with a two-loop accuracy

Ian Blokland·Andrzej Czarnecki·Maciej Slusarczyk·Fyodor Tkachov
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Abstract

We present a determination of a new class of three-loop Feynman diagrams describing heavy-to-light transitions. We apply it to find the O(alpha_s^2) corrections to the top quark decay t -> bW and to the distribution of lepton invariant mass in the semileptonic b quark decay b -> ulν. We also confirm the previously determined total rate of that process as well as the O(alpha^2) corrections to the muon lifetime.

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Ian Blokland, Andrzej Czarnecki, Maciej Slusarczyk, Fyodor Tkachov. 2004-03-19. Heavy-to-light decays with a two-loop accuracy. https://doi.org/10.1103/physrevlett.93.062001

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