Resonance amplification and T-violation effects in three-neutrino oscillations in the earth

The matter effects in three-neutrino oscillations in a beam of neutrinos passing through the earth are discussed. An exact analytic expression for the T-violating asymmetry in oscillations involving the three flavour neutrinos in matter with constant density is derived and it is shown that this asymmetry can be amplified considerably by matter. In particular, the T-violating asymmetry in the oscillations of neutrinos which have passed through the earth can be much larger than the analogous asymmetry in the oscillations in vacuum. (orig.)