Leptonic unitarity triangle and CP violation -: art. no. 113001

The area of the unitarity triangle is a measure of CP violation. We introduce the leptonic unitarity triangles and study their properties. We consider the possibility of reconstructing the unitarity triangle in future oscillation and nonoscillation experiments. A set of measurements is suggested which will, in principle, allow us to measure all sides of the triangle, and consequently to establish CP violation. For different values of the CP-violating phase delta(D), the required accuracy of measurements is estimated. The key elements of the method are the determination of parallel toU(e3)parallel to and studying the nu(mu)-nu(mu) survival probability in the oscillations driven by the solar mass splitting Deltam(sun)(2). We suggest additional astrophysical measurements which may help to reconstruct the triangle. The method of the unitarity triangle is complementary to the direct measurements of CP asymmetry. It requires mainly studies of the survival probabilities and processes where oscillations are averaged or the coherence of the state is lost.