Leptonic CP Violation at the neutrino factory

Abstract

In this talk, based on the work \cite{cpviolation}, we refine our previous analysis \cite{golden} of the sensitivity to leptonic CP violation and $\tetaot$ at a neutrino factory in the LMA-MSW scenario, by exploring the full range of these two parameters. We have discovered that there exist, at fixed neutrino energy, $E_\nu$, and baseline, $L$, degenerate solutions. Although the spectral analysis helps in disentangling fake from true solutions, a leftover product of this degeneracy remains for a realistic detector, which we analyse. Furthermore, we take into account the expected uncertainties on the solar and atmospheric oscillation parameters and in the average Earth matter density along the neutrino path. An intermediate baseline of O(3000) km is still the best option to tackle CP violation, although a combination of two baselines turns out to be very important in resolving degeneracies. This summary is based on a talk given at NUFACT01, May 2001, Tsukuba (Japan).