Inferred 4.4 eV Upper Limits on the Muon- and Tau-Neutrino Masses

Abstract

By combining experimental constraints from atmospheric and solar neutrino oscillations and the tritium beta decay endpoint, we infer upper limits of 4.4 eV on the $\hat{I}{½}_{\hat{I}}¼$ and $\hat{I}{½}_{\ddot{I}}„$ masses, if the universe consists of three neutrinos. For hierarchical mass spectra $m_3\gg m_1,m_2$ or $m_3\simeq m_2\gg m_1$ we infer that $m_{ν_α} \lsim 0.08$ eV for $\hat{I}\pm =e,\hat{I}¼,\ddot{I}„$. In a four neutrino universe, and assuming neutrino oscillations also account for the LSND experimental results, $m_{ν_α} \lsim 5.4$ eV. We also obtain lower limits on the masses.

7 pages, Revtex, uses epsf.sty, 1 postscript figure