Discovery limit of the charged Higgs boson via top quark decay at future hadron colliders

Abstract

We study the kinematic cuts which can be used to enhance the charged Higgs signal over the W boson background, for m_H± >m_w, in the decay of a heavy top quark at LHC energy. With suitable cuts it is possible to ensure a sizeable signal and a signal-to-background ratio ≳1 up to m_H± ⋍m_t-20 GeV, which hold throughout the allowed coupling parameter (tan β) space in the minimal SUSY model. Thus one should be able to search for the charged Higgs boson to within 20 GeV of the parent top quark mass at the LHC/SSC colliders, i.e., up to 130 GeV for m_t⋍150 GeV, going up to 180 GeV for m_tr⋍200 GeV.