Lr. Surguladze, QUARK MASS EFFECTS IN FERMIONIC DECAYS OF THE HIGGS-BOSON IN O(ALPHA(S)(2)) PERTURBATIVE QCD, Physics letters. Section B, 341(1), 1994, pp. 60-72
The results of analytical evaluation of O(alpha(s)(2)) QCD contributio
ns due to the nonvanishing quark masses to Gamma(H-->qf (q) over bar f
) are presented. The ''triangle anomaly'' type contributions are inclu
ded. As a byproduct the O(alpha(s)(3)) logarithmic contributions are e
valuated. The results are presented both in terms of running and pole
quark masses. The partial decay modes H --> b (b) over bar and H --> c
(c) over bar are considered. The calculated corrections decrease the
absolute value of large and negative O(a:) massless limit coefficient
by less than or equal to 1% in the intermediate mass region and by 1%-
20% in the low mass region which, however, is experimentally ruled out
. The results are relevant for H --> t (t) over bar decay mode for the
higher Higgs mass region where the mass effects are large and importa
nt The high order corrections remove a very large discrepancy between
the results for Gamma(H-->qf (q) over bar f) in terms of running and p
ole quark masses almost completely and reduce the scale dependence fro
m about 40% to nearly 5%. The remaining theoretical uncertainties are
discussed.