QCD corrections to Higgs boson self-energies and fermionic decay widths

We present the QCD corrections to Higgs boson self-energies for an arbitrary momentum transfer and for different internal quark masses to treat the case of CP-even, CP-odd, and charged Higgs bosons which appear in extensions of the standard model scalar sector. Using Ward identities, we then relate these results obtained by directly evaluating the relevant two-loop Feynman diagrams to the known expressions for the electroweak vector boson vacuum polarization functions. Finally, we derive the exact analytical expressions for the QCD corrections to the decays of these Higgs particles into quark pairs in the general case, and reproduce in a completely independent way known results in some special cases.