QCD corrections to the charged Higgs decay of a heavy quark

Abstract

We present an analytic formula for the $O({\alpha }_s)$ corrections to the decay $t\to H^{+}b$ for nonzero $m_H$ and $m_b$. The Equivalence Theorem is used to relate these corrections to those for the process $t\to W^{+}b$. Contrary to previously published results we find that the effect of the $b$ quark mass is negligible for a wide range of $m_t$, $m_H$ and $\tan \beta$.

Comments: 11 pages, Alberta Thy-34-92 and CfPA-92-26