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A Measurement of the Tau Topological Branching Ratios

The DELPHI Collaboration·P. Abreu
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Abstract

Using data collected in the DELPHI detector at LEP-1, measurements of the inclusive tau branching ratios for decay modes containing one, three, or five charged particles have been performed, giving the following results: B_1 = B(τ^- -> (particle)^- \geq 0pi^0 \geq 0K^0 ν_τ(\barν)) = (85.316 +/- 0.093 +/- 0.049)%; B_3 = B(τ^- -> 2h^-h^+ \geq 0pi^0 \geq 0K^0 ν_τ) = (14.569 +/- 0.093 +/- 0.048)%; B_5 = B(τ^- -> 3h^-2h^+ \geq 0pi^0 \geq 0K^0 ν_τ) = (0.115 +/- 0.013 +/- 0.006)%, where h is either a charged pi or K meson. The first quoted uncertainties are statistical and the second systematic.

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The DELPHI Collaboration, P. Abreu. 2001-05-18. A Measurement of the Tau Topological Branching Ratios. https://doi.org/10.1007/pl00011152

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