Measurement of neutrino-nucleus interactions with the upgraded ND280 detector at T2K

Tokai-to-Kamioka, T2K, is a long baseline experiment with the primary goal of investigating neutrino oscillations. This experiment uses a muon neutrino (or antineutrino) beam, produced at the J-PARC facility, targeting Super-Kamiokande (Super-K) which is positioned 295 km downstream of the beam at an off-axis angle of 2.5 degrees. The experiment also uses the ND280 off-axis near detector and by working in conjunction with the far detector, Super-K, measurements of the electron and muon neutrinos present in the beam before and after oscillation can be taken.
The ND280 near detector has the primary goal of measuring, and constraining, the neutrino flux and measuring the interaction cross sections. These measurements are used to estimate the varieties of neutrino interactions that would be observed at Super-K, reducing the systematic uncertainty in the measurements. Classification of the different events relies on the use of an accurate particle identification (PID), utilising the data collected by the ND280 sub-detectors to correctly identify each event. The dominant systematic uncertainty in the oscillation analysis is the cross-section uncertainty. However, the ND280 near detector is currently undergoing a major upgrade, removing one of the old detectors and installing all new sub-detectors in its place. These new detectors should significantly improve the performance and sensitivity of ND280. The new data that will be recorded by the upgraded ND280 near detector can then be exploited as to create an improved PID to improve event classification and reduce the systematic uncertainties of the measurements. The improved PID of the upgraded ND280 will be used to take measurements of the neutrino cross-section.