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Next-to-next-to-leading order calculations for heavy-to-light decays

I. Blokland·A. Czarnecki·M. Slusarczyk·F. Tkachov
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Abstract

We present technical aspects of next-to-next-to-leading order calculations for heavy-to-light decays such as top quark decay, semileptonic b quark decay into a u quark, muon decay, and radiative decays like b -> s gamma. Algebraic reduction of integrals to a set of master integrals is described, methods of determining the master integrals are presented, and a complete list of master integrals is given. As a sample application, the top quark decay width is calculated to O(alpha_s^2) accuracy.

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I. Blokland, A. Czarnecki, M. Slusarczyk, F. Tkachov. 2009-01-14. Next-to-next-to-leading order calculations for heavy-to-light decays. https://doi.org/10.1103/physrevd.71.054004%2010.1103%2Fphysrevd.79.019901

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