Corrections of O(\alpha_s^2) to the Decay of an Intermediate-Mass Higgs Boson into Two Photons

Abstract

The QCD correction of $O({\alpha }_s^2)$ to the decay of the Standard Model Higgs boson into two photons is presented. We consider the contribution coming from diagrams with a heavy top quark as virtual particle. The first three terms of the expansion in the inverse top mass is calculated. Expressing the result through the on-shell top mass M_t, we find large coefficients for the power-suppressed terms whereas in the $\overline{MS}$ scheme the coefficients are tiny.

Comments: 9 pages, LaTeX, 13 postscript figures. Contribution to the proceedings of the Ringberg Workshop, Tegernsee, Germany, 8-13 December 1996