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arXiv · hep-ex/9801029

Measurement of the one-prong hadronic tau branching ratios at LEP

The OPAL Collaboration·K. Ackerstaff et al
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Abstract

The branching ratios of the τ^- -> h^- ν_τ, τ^- -> h^- π^0 ν_τ, τ^- -> h^- >=2 π^0 ν_τdecays have been measured using the 1991-1995 data recorded with the OPAL detector at LEP. These branching ratios are measured simultaneously using three selection criteria and are found to be BR(τ^- -> h^- ν_τ) = (11.98 +/- 0.13 +/- 0.16)% BR(τ^- -> h^- π^0 ν_τ) = (25.89 +/- 0.17 +/- 0.29)% BR(τ^- -> h^- >=2 π^0 ν_τ) = ( 9.91 +/- 0.31 +/- 0.27)% where the first error is statistical and the second is systematic.

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The OPAL Collaboration, K. Ackerstaff et al. 1998-01-30. Measurement of the one-prong hadronic tau branching ratios at LEP. https://doi.org/10.1007/s100520050197

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