The Inclusive B̄ → τ ν̄ X Decay in Two Higgs Doublet Models
نویسنده
چکیده
We calculate in the framework of two Higgs doublet models the differential decay rate for inclusive B̄ → τ ν̄ X transitions to order 1/m2b in the heavy quark expansion, for both polarized and unpolarized tau leptons. In contrast to the situation in the standard model, we find sizeable 1/m2b corrections. A systematic heavy quark expansion significantly reduces the theoretical uncertainties in the calculation compared to the existing free quark decay model results. From the experimental measurement of the branching ratio, we derive the bound tan β < 0.51mH± [GeV]. We point out that the tau polarization is potentially a more sensitive probe of multi scalar models than the branching ratio itself.
منابع مشابه
Heavy Quark Expansion for the Inclusive Decay B̄ → τ ν̄ X
We calculate the differential decay rate for inclusive B̄ → τ ν̄ X transitions to order 1/m2b in the heavy quark expansion, for both polarized and unpolarized tau leptons. We show that using a systematic 1/mb expansion significantly reduces the theoretical uncertainties in the calculation. We obtain for the total branching ratio BR(B̄ → τ ν̄ X) = 2.30±0.25%, and for the tau polarization Apol = −0.7...
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