We explore the prospect of charged Higgs boson search in top quark decay at the Tevatron collider upgrade, taking advantage of the opposite states of $\tau$ polarization resulting from the $H^\pm$ and $W^\pm$ decays. Methods of distinguishing the two contr
narrows down to tanβ=3?10(2.5?12)for m H=100(120)GeV.Moreover one can probe for m H=140GeV except for a gap in the region tanβ=2?15.
For the sake of completeness we have computed the signal and background
√
cross-sections for the suggested Ditevatron energy of