Dark matter or neutrino recoil? Interpretation of recent experimental results

The elastic nuclear recoil signal, being under intense scrutiny by multiple underground experiments, can be interpreted either as coming from the interaction of nuclei with WIMP dark matter or from the scattering of new species of MeV-energy neutrinos. The most promising model for the latter case is a neutrino νb that interacts with baryon number and with a flux sourced by the oscillations of regular solar B8 neutrinos. We reanalyze this model in light of the latest experimental results. In contrast to the light-DM interpretation of various tentative positive signals (anomalies) that is now seriously challenged by the negative results of the LUX experiment, the neutrino interpretation remains a viable explanation to most of the anomalies. Considering future prospects, we show that the superCDMS experiment alone, when equipped with Ge and Si detectors, will be able to detect νb and discriminate the model from a light DM interpretation. In addition, we also provide the forecast for the new CRESST-II run that now operates with new detectors and diminished backgrounds.