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arXiv · hep-ex/9803031

A Limit on the Mass of the $ν_τ$

R. Ammar·CLEO Collaboration et al
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Abstract

A limit on the mass of the tau neutrino is derived from 4.5 million tau pairs produced in an integrated luminosity of 5.0 fb^{-1} of electron-positron annihilation to tau pairs at center of mass energies near 10.6 GeV. The measurement technique involves a two-dimensional extended likelihood analysis, including the dependence of the end-point population on the neutrino mass, and allows for the first time an explicit background contribution. We use the decays of the tau to five charged pions and a neutrino as well as the decay to three charged pions, two neutral pions and a neutrino to obtain an upper limit of 30 MeV/c^2 at 95% C.L.

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R. Ammar, CLEO Collaboration et al. 1998-03-31. A Limit on the Mass of the $ν_τ$. https://doi.org/10.1016/s0370-2693(98)00539-5

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