Measurement of three-family neutrino mixing and search for CP violation

The measurements of the parameters of the neutrino mixing matrix in the present and future neutrino oscillation experiments at accelerators are presented. The perspectives for high intensity new neutrino facilities as SuperBeams, BetaBeams and Neutrino Factories devoted to precise measurements subleading numu to nue oscillation parameters at the atmospheric scale are discussed. Emphasis is on the determination of the currently unknown 1-3 sector of the leptonic mixing matrix (i.e.the mixing between the first and third generation and the CP violating Dirac phase) and on possible experimental programs to be developed in Europe. 1 Neutrino oscillations The experimental evidences for neutrino oscillations collected in the last six years represent a major discovery in modern particle physics. The oscillation phenomenon allows the measurement of fundamental parameters of the Standard Model and provides the first insight beyond the electroweak scale [1]. Moreover, they are important for many fields of astrophysics and cosmology and open the possibility to study CP violation in the leptonic sector. Neutrino flavor oscillations can be described in term of three mass eigenstates ν1, ν2, ν3 with mass values m1, m2 and m3 that are connected to the flavor eigenstates νe, νμ and ντ by a mixing matrix U , usually parameterized as U(θ12, θ23, θ13, δCP ) =   c13c12 c13s12 s13e −iδCP −c23s12 − s13s23c12eCP c23c12 − s13s23s12eCP c13s23 s23s12 − s13c23c12eCP −s23c12 − s13c23s12eCP c13c13 