Electroweak Corrections to the Deacy H^+to W^+h in the Minimal Supersymmetric Model

We calculate the $O(\alpha_{ew}m_{t(b)}^{2}/m_{W}^{2})$ and $O(\alpha_{ew} m_{t(b)}^4/m_W^4)$ supersymmetric electroweak corrections to the process $H^+\to W^+h$ in the Minimal Supersymmetric Model. These corrections arise from the virtual effects of the third family quaurks (top and bottom) and squarks (top-squark and bottom-squark). We find that for $m_{H^+}>200$GeV at low $\tan\beta(\leq 3)$, the corrections can increase the tree-level decay widths and the branching radios more than 20% and 40%, respectively.