NEP-ton: Lead glass neutrino experiments at the SNS

In 2015, the COHERENT collaboration measured the electron-neutrino charged-current (CC) cross-section on lead. The Eljen cell and the Neutrino Cubes detectors hunted for the Neutrino Induced Neutrons (NINs) produced by this process. The results indicated a surprisingly small cross-section — less than one third of the predicted signals were observed. Understanding the NINs production rate is crucial for COHERENT, seeing as lead is a common shielding material for the detector subsystems used. To further investigate this curiosity, a new experiment, NEP-ton, will search for this process by detecting only the resulting lepton produced, instead of the secondary neutron. Lead glass is both the target material and the detection medium, which is made possible because it is transparent to the Cherenkov radiation produced by the lepton. The goal is to seek a concrete measurement of this cross-section using NEP-ton, a 640kg array of repurposed lead glass. Planning is also underway for Plνt³o, a multi-tonne lead glass detector, which will build on NEP-ton and will be able to perform a precision search for sterile neutrinos.