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Measurement of the Branching Ratio for the Process b -> tau nu X

The OPAL collaboration·G. Abbiendi
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Abstract

The inclusive branching ratio for the process b -> tau nu X has been measured using hadronic Z decays collected by the OPAL experiment at LEP in the years 1992-2000. The result is: BR(b -> tau nu X) = (2.78 +/- 0.18 +/- 0.51)% This measurement is consistent with the Standard Model expectation and puts a constraint of tan(beta) / M(H+/-) < 0.53 GeV-1 at the 95% confidence level on Type II Two Higgs Doublet Models.

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The OPAL collaboration, G. Abbiendi. 2001-08-16. Measurement of the Branching Ratio for the Process b -> tau nu X. https://doi.org/10.1016/s0370-2693(01)01012-7

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