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
Theρmeson line shape factor is
fρ(m2)=(1?4m2π/m2)3/2(37)
which takes account of the P-wave threshold behavior forρ→ππdecay.For the line shape of the a1meson we shall use the phenomenological parametrisation of Kuhn and Santamaria[15]
f a(m2)=1.623+10.38
m4
+
0.65
ΓππdΓ(ρ±L→π±π0)
2
cos2θ′?3
ΓππdΓ(ρ±T→π±π0)
4
sin2θ′?3x′(1?x′)(40) x′= 1+
s
(45)
where we have dropped a constant multiplicative factor in(44),which will not be relevant for our analysis.It will be adequate for our purpose to evaluate the
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