Speaker
Description
Precision neutrino oscillation measurements rely on reconstructing the incident neutrino energy from the observed final state. In neutrino–nucleus interactions, nuclear effects can distort the relationship between reconstructed kinematics and the underlying energy and momentum transfer, introducing model dependence into neutrino-energy reconstruction.
The superscaling variable (ψ′) is studied as a probe of nuclear effects in charged-current interactions without pions at the Tokai to Kamioka (T2K) ND280 Upgrade detector. These studies demonstrate that the correlation between ψ′ and the reconstructed proton-energy imbalance connects departures from the quasielastic response to shifts in reconstructed neutrino energy, directly linking nuclear effects to oscillation measurements.
An alternative-model closure study within the near-detector fit has also been performed to test whether the nominal model can reproduce predictions from a different nuclear model. Projecting the pre- and post-fit predictions into these observables shows which model differences are constrained and which remain, providing a direct diagnostic of nuclear-model effects on neutrino-energy reconstruction and the near-to-far extrapolation. Such diagnostics will be increasingly important for next-generation experiments such as Hyper-Kamiokande.