Heavy-to-light-quark decays with two-loop accuracy.
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(alpha2(s)) corrections to the top quark decay t --> bW and to the distribution of lepton invariant mass in the semileptonic b quark decay b --> ulnu. We also confirm the previously determined total rate of that process as well as the O(alpha2) corrections to the muon lifetime.
Department of Physics, University of Alberta, Edmonton, AB T6G 2J1, Canada.
Ian
I
Blokland
Andrzej
A
Czarnecki
Maciej
M
Slusarczyk
Fyodor
F
Tkachov