Measurement of Neutrino Oscillations with the MINOS Detectors in the NuMI Beam

The data disfavor two alternative explanations for the disappearance of neutrinos in flight: namely, neutrino decays into lighter particles and quantum decoherence of neutRinos, at the 3.7 and 5.7 standard-deviation levels, respectively.

Abstract

This Letter reports new results from the MINOS experiment based on a two-year exposure to muon neutrinos from the Fermilab NuMI beam. Our data are consistent with quantum-mechanical oscillations of neutrino flavor with mass splitting $|\ensuremath{\Delta}{m}^{2}|=(2.43\ifmmode\pm\else\textpm\fi{}0.13)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}3}\text{ }\text{ }{\mathrm{eV}}^{2}$ (68% C.L.) and mixing angle ${sin}^{2}(2\ensuremath{\theta})>0.90$ (90% C.L.). Our data disfavor two alternative explanations for the disappearance of neutrinos in flight: namely, neutrino decays into lighter particles and quantum decoherence of neutrinos, at the 3.7 and 5.7 standard-deviation levels, respectively.