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The next generation of long baseline neutrino oscillation experiments will aim at determining the unknown mixing angle $\theta_{13}$, the type of neutrino mass hierarchy and CP-violation. We discuss the separation of these properties by means of the energy dependence of the oscillation probability and we consider an hybrid setup which combines the electron capture and the $\beta^+$ decay from the same radioactive ion with the same boost. We study the sensitivity to the mixing angle and the CP-phase, the CP discovery potential and the reach to determine the type of neutrino mass hierarchy. The analysis is performed for different boosts and baselines. We conclude that the combination of the two decay channels, with different neutrino energies, achieves remarkable results., Comment: 21 pages, 8 figures. Talk given at 13th International Workshop on Neutrino Telescopes, Venice, March 10-13, 2009

The ultimate goal for future neutrino facilities is the determination of CP violation in neutrino oscillations. Besides $| U(e3) | \ne 0$, this will require precision experiments with a very intense neutrino source and energy control. With this objective in mind, the creation of monochromatic neutrino beams from the electron capture decay of boosted ions by the SPS of CERN has been proposed. We discuss the capabilities of such a facility as a function of the energy of the boost and the baseline for the detector. We compare the physics potential for two different configurations: I) $��=90$ and $��=195$ (maximum achievable at present SPS) to Frejus; II) $��=195$ and $��=440$ (maximum achievable at upgraded SPS) to Canfranc. We conclude that the SPS upgrade to 1000 GeV is important to reach a better sensitivity to CP violation iff it is accompanied by a longer baseline. In both Setups, the gain in the CP violation sensitivity with a previous knowledge of $| U(e3) |$ is apparent., 11 pages, 7 figures

The goal for future neutrino facilities is the determination of the $[U_{e3}]$ mixing and CP violation in neutrino oscillations. This will require precision experiments with a very intense neutrino source. With this objective the creation of neutrino beams from the radioactive decay of boosted ions by the SPS of CERN from either beta or electron capture transitions has been propossed. We discuss the capabilities of such facilities as a function of the energy of the boost and the baseline for the detector. We conclude that the SPS upgrade to 1000 GeV is crucial to have a better sensitivity to CP violation if it is accompanied by a longer baseline. We compare the physics potential for two different configurations. In the case of beta beams, with the same boost for both $\beta^+$ (neutrinos) and $\beta^-$ (antineutrinos), the two setups are: I) $\gamma=120$, L=130 Km (Frejus); II) $\gamma=330$, L=650 Km (Canfranc). In the case of monochromatic EC beams we exploit the energy dependence of neutrino oscillations to separate out the two parameters $U(e3)$ and the CP phase $\delta$. Setup I runs at $\gamma=90$ and $\gamma=195$ (maximum achievable at present SPS) to Frejus, whereas Setup II runs at $\gamma=195$ and $\gamma=440$ (maximum achievable at upgraded SPS) to Canfranc. The main conclusion is that, whereas the gain in the determination of $U(e3)$ is rather modest, setup II provides much better sensitivity to CP violation., Comment: 6 pages, 10 figures, Proceedings of LHC LUMI 2006 CARE-HHH-AP Wokshop, October 2006, Valencia

The goal for future neutrino facilities is the determination of the $[U_{e3}]$ mixing and CP violation in neutrino oscillations. This will require precision experiments with a very intense neutrino source. Here a novel method to create a monochromatic neutrino beam based on the recent discovery of nuclei that decay fast through electron capture is discussed. The boost of such radioactive ions will generate a monochromatic directional neutrino beam when decaying at high energy in a storage ring with long straight sections. We show that the capacity of such a facility to discover new physics is impressive, so that the principle of energy dependence in the oscillation probability of the $\nu_e \to \nu_{\mu}$ channel is operational to separate out the two parameters of the mixing $\theta_{13}$ and of the CP-violating phase $\delta$., Comment: 16 pages, 7 figures, Proc. 3rd. International Workshop on NO-VE: Neutrino Oscillations in Venice, 7-10 February 2006, Venice