Optimization of neutrino oscillation facilities for large \theta_{13}

TL;DR

This paper suggests re-optimizing neutrino oscillation experiments by targeting the second oscillation peak, which enhances CP violation discovery potential, reduces systematic impact, and improves mass hierarchy sensitivity, especially if 3 is large.

Contribution

It introduces a re-optimization strategy focusing on the second oscillation peak for neutrino experiments, improving their sensitivity and robustness in the case of larger 3.

Findings

Enhanced CP discovery potential at the second peak.

Reduced impact of systematic uncertainties.

Improved sensitivity to mass hierarchy with larger L/E.

Abstract

Up to now, future neutrino beam experiments have been designed and optimized in order to look for CP violation, \theta_{13} and the mass hierarchy under the conservative assumption that \theta_{13} is very small. However, the recent results from T2K and MINOS favor a \theta_{13} which could be as large as 8^{\circ}. In this work, we propose a re-optimization for neutrino beam experiments in case this hint is confirmed. By switching from the first to the second oscillation peak, we find that the CP discovery potential of future oscillation experiments would not only be enhanced, but it would also be less affected by systematic uncertainties. In order to illustrate the effect, we present our results for a Super-Beam experiment, comparing the results obtained at the first and the second oscillation peaks for several values of the systematic errors. We also study its combination with a \beta-beam facility and show that the synergy between both experiments would also be enhanced due to the larger L/E. Moreover, the increased matter effects at the larger L/E also significantly improves the sensitivity to the mass hierarchy.