Two-loop heavy Higgs corrections to the Higgs fermionic width

Abstract

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