Tests of three-flavor mixing in long-baseline neutrino oscillation experiments

We compare the effectiveness of various tests of three-flavor mixing in future long-baseline neutrino oscillation experiments. We analyze a representative case of mixing in a simplified three-flavor scheme, whose relevant parameters are one neutrino mass-square difference, $m^2$, and two mixing angles, $\psi$ and $\phi$. We show that an unambiguous determination of $\psi$ and $\phi$ requires flavor-appearance tests in accelerator experiments, as well as supplementary information from reactor experiments.