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Mass effects in muon and semileptonic b-->c decays
Alexey Pak1, Andrzej Czarnecki
1Department of Physics, University of Alberta Edmonton, AB T6G 2G7, Canada.
Abstract:
Quantum chromodynamics (QCD) effects in the semileptonic decay b-->clnu are evaluated to the second order in the coupling constant, O(alpha(s){2}), and to several orders in the expansion in quark masses, m{c}/m{b}. Corrections are calculated for the total decay rate as well as for the first two moments of the lepton energy and the hadron system energy distributions. Translated into QED and applied to the muon decay, they decrease its predicted rate by -0.43 ppm.
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