QCD and SUSY-QCD corrections to the Three-Body Decay of the Charged Higgs Boson

Abstract

The $\mathcal{O}({\alpha }_s)$ QCD corrections to the three-body decay width of the charged Higgs $\Gamma$($H^{+}\to W^{+}b\bar{b}$) are discussed in the MSSM model. Our calculations indicate that the standard QCD corrections to the three-body decay mode raise the width by about 12% and the supersymmetric QCD corrections(due to $\tilde{g},\tilde{t},\tilde{b}$ exchanges) can be comparable to or even larger than the standard QCD corrctions in some regions of the supersymmetric parameter space. This is mainly due to the effect of large left-right mixing of stop($\tilde{t}$). It could significantly affect the phenomenology of the $H^{+}$ search.

Comments: 14 pages, 14figures