Testing Flavor Changing Neutrino Interactions in Long Baseline Experiments

We have investigated the possibility of discerning mass from flavor changing neutrino interactions induced $\nu_\mu \to \nu_\tau$ oscillations in the long baseline neutrino experiments K2K and MINOS. We have found that for virtually any value of the flavor conserving parameter $\epsilon^\prime$ it will be possible to, independently, distinguish these two mechanisms at K2K, if the flavor changing parameter $\epsilon$ is in the range $\epsilon \gsim 0.77$, and at MINOS, if $\epsilon \gsim 0.2$. Moreover, if K2K measures a depletion of the expected $\nu_\mu$ flux then MINOS will either observe or discard completely flavor changing neutrino oscillations.