  The (inverse) beta-decay of uniformly accelerated protons (p -> n + e+ + ne)
has been recently analyzed in the context of two-flavor neutrino mixing and
oscillations. It has been shown that the decay rates as measured by an inertial
and comoving observer are in agreement, provided that: i) the thermal nature of
the accelerated vacuum (Unruh effect) is taken into account; ii) the asymptotic
behavior of neutrinos is described through flavor (rather than mass)
eigenstates; iii) the Unruh radiation is made up of oscillating neutrinos. Here
we extend the above considerations to a more realistic scenario including three
generations of Dirac neutrinos. By following the outlined recipe, we find that
the equality between the two rates still holds true, confirming that mixing is
perfectly consistent with the General Covariance of Quantum Field Theory.
Notably, we prove that the analysis of CP violation in neutrino oscillations
provides a further solid argument for flavor states as fundamental
representation of asymptotic neutrino states. Our approach is finally discussed
in comparison with the other treatments appeared in literature.
