Two-loop heavy Higgs corrections to the Higgs fermionic width

摘要

We calculate the two--loop electroweak corrections to the fermionic decay width of the Higgs boson at leading order in m_{H}. The sum of one--loop and two--loop radiative corrections turns out to be at 6% level over the whole range of m_{H} where the perturbation theory is supposed to be a sensible approximation. We show that the perturbative approach breaks down at m_{H} \sim 1.4 TeV, and address the question of its relevance beyond this limit.