Probing Nuclear Effects at the T2K Near Detector Using Transverse Kinematic Imbalance

Abstract

In this work we utilise variables characterising kinematic imbalance in the plane transverse to an incoming neutrino, which have recently been shown to act as a direct probe of nuclear effects (such as final state interactions, Fermi motion and multi-nucleon processes) in $\mathcal{O}$(GeV) neutrino scattering. We present a methodology to measure the charged current differential cross-section with no final state pions and at least one final state proton ($CC0π+Np, N \geq 1$) in these variables at the near detector of the T2K experiment (ND280), using the upstream Fine Grained Detector (FGD1) as a hydrocarbon target. Overall these measurements will allow us to better understand the impact of nuclear effects on the observables in neutrino scattering, providing valuable constraints on the systematic uncertainties associated with neutrino oscillation and scattering measurements for both T2K and other experiments with similar energy neutrino beams.