The flavor of neutrinos in muon decays at a neutrino factory and the LSND puzzle

The accurate prediction of the neutrino beam produced in muon decays and theabsence of opposite helicity contamination for a particular neutrino flavormake a future neutrino factory the ideal place to look for the lepton flavorviolating (LFV) decays of the kind $\mu^+\ra e^+\nuebar\numu$ and lepton numberviolating (LNV) processes like $\mu^-\ra e^-\nue\numu$. Excellent sensitivitiescan be achieved using a detector capable of muon and/or electron identificationwith charge discrimination. This would allow to set experimental limits thatimprove current ones by more than two orders of magnitude and test thehypothesis that the LSND excess is due to such anomalous decays, rather thanneutrino flavor oscillations in vacuum.Comment: 19 pages, 4 figure