HUNTER: Sterile Neutrino Search
Neutrino flavor oscillations and the predicted sub-eV values of the neutrino mass eigenstates point to physics beyond the Standard Model. Enormous insight would be gained from the discovery of a hypothetical particle called a sterile neutrino, getting its name from its complete lack of weak interactions. Potentially orders of magnitude heavier than their active versions, they could naturally explain the observed small mass splittings, and despite their abstinence from standard model interactions, could be detected through mixing with the active neutrinos. HUNTER (Heavy Unseen Neutrinos by Total Energy-Momentum Reconstruction) is a kinematic reconstruction experiment to search for keV-mass sterile neutrinos using electron capture isotope 131Cs (t = 9.7 days). Phase I will improve on existing laboratory limits, and pave the way for Phases II and III of this multi-institution, interdisciplinary experiment. In this project, in collaboration with Prof. Paul Hamilton, we are developing a radioactive 131Cs MOT which will serve as the continuously operated decay source, and contributing to the design of the spectrometer which will detect x-rays, 131Xe+, and Auger electrons with sufficient resolution to probe the mν = 30 - 300 keV mass range.