Speaker: Andrew Olivier (Notre Dame)

Abstract: Neutrino oscillations are the key to unlocking two of the final puzzles of the Standard Model: neutrino masses and CP violation in the lepton sector. Accelerator-based oscillation experiments with O(1 GeV) neutrinos are a promising method to measure these properties. GeV-scale charged leptons from these neutrinos are easy to measure, but the hadrons they produce are not. Interactions inside the target nucleus make O(100 MeV) changes to the hadrons detected, and neutrons invisibly carry energy away from the interaction. The MINERvA neutrino scattering experiment has helped constrain nuclear effects in neutrino scattering since 2009. New sensivity to neutrons at MINERvA presents an opportunity for novel cross section measurements. The MINERvA collaboration recently used neutron direction reconstruction to isolate the cross section for antineutrino interactions on a free proton. Our latest result, the multi-neutron production cross section, opens new windows for understanding nuclear effects.