New constraints on the tau neutrino mass and fourth generation mixing

John Swain; Lucas Taylor

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arXiv · hep-ph/9712383

New constraints on the tau neutrino mass and fourth generation mixing

John Swain·Lucas Taylor

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Abstract

We present new constraints on the mass $m_{ν_τ}$ of the tau neutrino and its mixing with a fourth generation neutrino. From an analysis of the partial widths of tau lepton decays we obtain the following bounds at the 90% confidence level: $m_{ν_τ} < 32$ MeV and $\sin^2θ< 0.007$, where $θ$ describes the Cabibbo-like mixing of the third and fourth generation neutrinos.

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John Swain, Lucas Taylor. 1997-12-15. New constraints on the tau neutrino mass and fourth generation mixing. https://arxiv.org/abs/hep-ph/9712383

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