QCD corrections to charged Higgs - mediated b → c τ ν decay
نویسندگان
چکیده
We calculate the O(αs) corrections to the charged Higgs mediated inclusive semi-tauonic B decay. By working in the Landau gauge, we demonstrate how to obtain the charged Higgs contributions (both direct and interference terms) from the known QCD corrections to t → bH+. Combining our results with O(1/mb) corrections to the spectator model and comparing the theoretical prediction with the recent experimental measurements, we find a model-independent 2σ upper bound on the ratio of Higgs vacuum expectation values, tanβ < 0.52 (mH/1GeV). CERN-TH/95-182 July, 1995 Permanent address: Santa Cruz Institute for Particle Physics, University of California, Santa Cruz, CA 95064 USA.
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