Physics and Astronomy Colloquium

The MiniBooNE neutrino oscillation experiment at Fermilab has reported first results ruling out a two neutrino oscillation interpretation of the LSND signal. The LSND experiment observed electron anti-neutrino appearance in a muon anti-neutrino beam. Taken with other evidence for neutrino oscillations, the LSND measurement suggests the existence of physics beyond the standard model in the neutrino sector. MiniBooNE has performed two independent and blind oscillation searches for electron neutrino appearance in a muon neutrino beam. In both, analysis selections and fitting procedures were determined before candidate electron neutrino events were examined. While MiniBooNE did not observe oscillations as expected in the analysis region, an excess of events was observed at low energy. There are a number of models suggesting these events could signal new physics. Ongoing studies to understand these events will be presented. A follow-on experiment to address this low energy excess will be described.