A Comparison of the Physics Potential of Future Long Baseline Neutrino Oscillation Experiments ∗

We compare the generic physics potential of various combinations of conventional Wide Band or Neutrino Factory Beams with different detectors to determine several oscillation parameters in long baseline experiments. For each combination of beam and detector we show the precision which can be obtained for the leading oscillation parameters ∆m 31 and sin 2θ23. Furthermore we show the sensitivity to sin 2θ13 and the range in sin 2 2θ13 for which the sign of ∆m 2 31 can be extracted via matter effects. The results suggest that existing conventional Wide Band Beam and detector technology can be used to considerably improve the precision of neutrino properties until a neutrino factory will be built. Recent studies of neutrino factories as powerful neutrino sources have shown that precision measurements of neutrino masses and mixings are possible in the future [1]. The development of a neutrino factory includes however challenging technological issues and the development will certainly take some time. It is therefore of interest what can be achieved meanwhile in comparison by using conventional neutrino beams. Such improved conventional experiments will lead to a better knowledge of neutrino parameters, which might be considered as a useful step to simply bridge the time until a neutrino factory will be operating. We will however show in this paper that conventional setups may be able to compete in some aspects with the long baseline neutrino oscillation program of neutrino factories. The results of such intermediate experiments would also be important since they affect the optimal strategies for neutrino factories. This applies especially to the measurement of CPviolation at neutrino factories, where further advance information on the mixing parameters ∗Work supported by ”Sonderforschungsbereich 375 für Astro-Teilchenphysik” der Deutschen Forschungsgemeinschaft. Email: [email protected] Email: [email protected] Email: [email protected]–muenchen.de Email: [email protected]–muenchen.de