Corrections of Order ${\cal O}(G_F\alpha_s m_t^2)$ to the Higgs Decay Rate $\Gamma(H\to b\bar{b})$

Abstract

QCD corrections to the electroweak one-loop result for the partial width $\Gamma(H\rightarrow b\bar{b})$ are studied. For the decay channel into bottom quarks the rate is affected by a virtual top quark through electroweak interactions. The calculation of QCD corrections to this quantity is performed for an intermediate range Higgs mass in the heavy top mass limit. The leading correction of order ${\cal O}(G_F\alpha_s m_t^2)$ is estimated. Numerically the contribution is of comparable size as the electroweak correction, but of opposite sign.