Probing Neutrino Oscillations at Very Short Baselines with Reactors and Radioactive Sources
Data from a variety of neutrino experiments as well as cosmology seem to suggest the existence of additional light, sterile neutrino states. A re-analysis of short-baseline reactor neutrino experiments recently revealed a discrepancy of about 5.7%, or ˜2.5σ, between the measured reactor antineutrino flux and predictions. This reactor anomaly can be interpreted as a sign of new physics, or could be due to uncertainties in the nuclear physics underlying reactor antineutrino flux and spectrum predictions. A new experiment at very short baselines of O(10m) is needed to test the hypothesis of oscillation into sterile neutrinos and to make a precision measurement of the reactor antineutrino spectrum. US research reactors with highly-enriched fuel and compact cores provide a unique opportunity for a definitive reactor experiment at very short-baselines. Alternatively, radioactive antineutrino sources may be used in existing detector facilities. We discuss the experimental prospects for resolving this neutrino anomaly.
