Light Fermionic Dark Matter and its Possible Detection in Neutrino Experiments

We explore the potential for the direct detection of light fermionic dark matter in neutrino detectors. We consider the possible observation of the process $\bar{f} p \to e^+ n$, where $f$ is a dark matter fermion, in a model-independent manner. All operators of dimension six or lower which can contribute to this process are listed, and we place constraints on these operators from decays of $f$ which contain $\gamma$ rays or electrons. One operator is found which is sufficiently weakly constrained that it could give observable interactions in neutrino detectors. We find that Super-Kamiokande can probe the new physics scale for this operator up to $O(100{TeV})$.