Next-Order Estimate of Higgs to Two-Gluon Rate

Abstract

Using asymptotic Pade approximant methods, we have calculated the O(alpha_s^5) contribution to the Standard-Model H to gg decay rate. This process is of particular interest because of the slow convergence evident from the known terms of its QCD series. The O(alpha_s^5) term is expressed as a 3rd degree polynomial in $L= log (\frac{\mu^2}{m_t^2(\mu)})$. We find that the asymptotic Pade predictions for the renormalization-group accessible coefficients of L, L^2 and L^3 are within 1%, 2% and 7% of their respective values. The inclusion of the O(alpha_s^5) contribution renders the full decay rate virtually scale independent over the entire 0.3 M_H < mu < M_t range of the renormalization scale mu.