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 ${\nu }_{\mu }$ and ${\nu }_{\tau }$ 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 $m_{{\nu }_{\alpha }}\text{lsim}0.08$ eV for $\alpha =e,\mu ,\tau$. In a four neutrino universe, and assuming neutrino oscillations also account for the LSND experimental results, $m_{{\nu }_{\alpha }}\text{lsim}5.4$ eV. We also obtain lower limits on the masses.

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