Consequences of Majorana and Dirac Mass Mixing for Neutrino Oscillations

This Letter considers a second class of neutrino oscillations which can arise when both Majorana and Dirac neutrino mass terms exist. These oscillations mix neutrino members of weak current doublets with singlets of the same chirality. A depletion of a neutrino beam results, with apparent nonconservation of probability. Possible relevance to current oscillation experiments is discussed.