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

TL;DR

This paper reports precise measurements of specific one-prong hadronic tau decay branching ratios using data from the OPAL detector at LEP, providing important tests of the Standard Model.

Contribution

It presents the first simultaneous measurement of three tau decay branching ratios with detailed statistical and systematic uncertainties.

Findings

Measured branching ratios with improved precision

Consistent with Standard Model predictions

Provides data for testing tau decay models

Abstract

The branching ratios of the \tau^- -> h^- \nu_\tau, \tau^- -> h^- \pi^0 \nu_\tau, \tau^- -> h^- >=2 \pi^0 \nu_\tau decays 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(\tau^- -> h^- \nu_\tau) = (11.98 +/- 0.13 +/- 0.16)% BR(\tau^- -> h^- \pi^0 \nu_\tau) = (25.89 +/- 0.17 +/- 0.29)% BR(\tau^- -> h^- >=2 \pi^0 \nu_\tau) = ( 9.91 +/- 0.31 +/- 0.27)% where the first error is statistical and the second is systematic.