Extracting matter effects, masses and mixings at a neutrino factory Original Research Article

We discuss and quantify different possibilities to determine matter effects, the value and the sign of Δm231 , as well as the magnitude of sin22θ13 in very long baseline neutrino oscillation experiments. We study neutrino oscillation at a neutrino factory in the νμ→νμ disappearance and νe→νμ appearance channels with and without muon charge identification. One possibility is to analyze the νe→νμ appearance channels leading to wrong sign muon events, which requires however very good muon charge identification. Without charge identification it is still possible to operate the neutrino factory both with μ− and μ+ beams and to analyze the differences in the total neutrino event rate spectra. We show that this leads already to a quite good sensitivity, which may be important if right sign charge rejection capabilities are insufficient. With muon charge identification one can study the νμ→νμ disappearance and the νe→νμ appearance channels independently. The best method is finally achieved by combining all available information of the νμ→νμ disappearance and νe→νμ appearance channels with charge identification and we show the sensitivity which can be achieved.