CP-Violation in 3- and 4-family at the Neutrino Factory

The leptonic CP-violating phase δ can be measured with a Neutrino Factory with 2 × 10 useful muons per year, if the solar neutrino problem is solved by the LMA-MSW solution, with ∆m212 ≥ 2 × 10 −5 eV (in this analysis a 40 kT magnetized iron detector is considered, taking into account its efficiencies and backgrounds). If LSND is confirmed, CP-violating phenomena in four-family scenarios can be most easily addressed with a small 1 kT detector at L = O(10) km (no detailed analysis of the detector efficiencies and backgrounds has been performed in this case).