07/02/2026
Another new measurement from MicroBooNE, probing what happens when a neutrino interacts deep enough inside an argon nucleus to create a resonance: exciting one of the protons or neutrons up to a higher-energy state, which can then decay to produce a new particle such as a pion.
When a muon neutrino strikes an argon nucleus and produces a neutral pion, the particles that emerge should balance their momenta in the plane perpendicular to the beam. They don't quite, and that imbalance tells us about the nuclear physics inside the argon: the motion of the struck nucleon, and the re-scattering of particles on their way out. By measuring this 'transverse kinematic imbalance' with the muon, proton and pion, we can test how well our models capture these effects.
We find that none of the leading neutrino simulations reproduce all of the data, and this matters because these nuclear effects are among the largest uncertainties facing the next generation of oscillation experiments, including the Deep Underground Neutrino Experiment.
Neutrino-nucleus cross-section measurements are needed to improve interaction modeling and to enable precision neutrino oscillation measurements in upcoming experiments such as the Deep Underground Neutrino Experiment (DUNE), Hyper-Kamiokande, and the Short-Baseline Neutrino program. Baryon-resonanc...