Yukawa Corrections to Charged Higgs Boson Production in Association with a Top Quark at Hadron Colliders

We calculate the Yukawa corrections of order $O(\alpha_{ew}m_{t(b)}^{2}/m_{W}^{2})$ to charged Higgs boson production in association with a top quark at the Tevatron and the LHC. The corrections are not very sensitive to the mass of the charged Higgs boson and can exceed -20% for low values of $\tan\beta$, where the contribution of the top quark is large, and high values of $\tan\beta$ where the contribution of the bottom quark becomes large. These Yukawa corrections could be significant for charged Higgs boson discovery searches based on this production process, particularly at the LHC where the cross section is relatively large.