Regular Article - Theoretical Physics
Neutrino mixing and the exponential form of the Pontecorvo–Maki–Nakagawa–Sakata matrix
Gruppo Fisica Teorica e Matematica Applicata Unita Tecnico Scientifica Tecnologie Fisiche Avanzante (FIS-MAT), ENEA – Centro Ricerche Frascati, Via Enrico Fermi 45, 00044, Frascati, Rome, Italy
2 Dept. of Optics and Spectroscopy, Faculty of Physics, M.V. Lomonosov Moscow State University, Moscow, 119991, Russia
Revised: 25 March 2008
Published online: 27 May 2008
The form of the neutrino mixing matrix is discussed. The exponential parameterisation of the Pontecorvo–Maki–Nakagawa–Sakata (PMNS) matrix is proposed and the generation of the new unitary parameterisation of the neutrino mixing matrix by the exponential form is demonstrated. The CP violating phase and the Majorana phases in the PMNS matrix are accounted for by a special term, separated from the rotational one. The O(3) rotation matrix in the angle-axis form is discussed in the context of such a representation of the mixing matrix. Its properties are reviewed in the context of the unitarity requirement.
© Springer-Verlag , 2008