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Bound on the tau neutrino magnetic moment from the TRISTAN experiments

N. Tanimoto·I. Nakano·M. Sakuda
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Abstract

We set limits on the magnetic moment and charge radius of the tau neutrino by examining an extra contribution to the electroweak process $e^+ e^- \to ν\barνγ$ using VENUS, TOPAZ and AMY results. We find that $κ(ν_τ) < 9.1\times{10}^{-6}$ (i.e. $μ(ν_τ) < 9.1\times{10}^{-6}μ_B, μ_B = e/2m_e$) and $ < 3.1\times{10}^{-31}$cm$^2$ with Poisson statistics by combining their results. Whereas, similar to this method, with the Unified Approach we find that $κ(ν_τ) < 8.0\times{10}^{-6}$ and $ < 2.7\times{10}^{-31}$cm$^2$.

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N. Tanimoto, I. Nakano, M. Sakuda. 2000-02-16. Bound on the tau neutrino magnetic moment from the TRISTAN experiments. https://doi.org/10.1016/s0370-2693(00)00256-2

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