Eur. Phys. J. C (2013) 73: 2434
https://doi.org/10.1140/epjc/s10052-013-2434-6

Regular Article - Theoretical Physics

Dissipation and θ ₁₃ in neutrino oscillations

Instituto de Física Gleb Wataghin, Universidade Estadual de Campinas, Unicamp, 13083-970, Campinas, São Paulo, Brazil

^* e-mail: robertol@ifi.unicamp.br

Received: 25 October 2012
Revised: 21 March 2013
Published online: 22 May 2013

Abstract

We obtain a complete survival and transition probability involving three neutrino flavors when dissipation effects in vacuum are taken into consideration. In an approach that presents decoherence and relaxation effects, we study the behavior of the probabilities obtained from complete positivity constraints. Making the von Neumann entropy increase in time, many cases can be obtained and studied with the Lindblad master equation with addition of only one or two parameters related to dissipation. New possibilities are obtained when we take into account two decoherence parameters with different magnitudes which are given by reactor and accelerator neutrino oscillation experiments. We also present a model with only one parameter that has an important symmetry property, which can be used when the effective matter potential is important. Furthermore, the dissipation effects can contribute to the appearance of neutrinos that can hide or imitate the θ ₁₃ effects and we study these possibilities showing that dissipative effects have an important role in three-neutrino oscillations.