Fermion mass effects on Γ(Z → bb + a light Higgs) in a two-Higgs-doublet model

A large fermion mass effect on the Yukawa process Z → bb → bbh(A) in the entire range of neutral Higgs boson masses is found. This is particularly important for light Higgs bosons, which are still not excluded experimentally in a general two-Higgs-doublet model.