The status of neutrino interaction theory and its impact on future neutrino oscillation experiments

Abstract

Over the last decade, there has been enormous effort to measure neutrino interaction cross sections important to oscillation experiments. However, a number of results from modern experiments appear to be in tension with model predictions. It also has been known that our models are outdated and with assumptions for simplicity therefore, many efforts have been devoted to the quasielastic peak and dip region to improve them but very little attention has been given to the resonance and higher regions. The MK model provides a full kinematic description of single pion production in the neutrino-nucleon interactions, including resonant and nonresonant interactions in the helicity basis, in order to study the interference effect. The MK model shows better agreements with data compare to the exciting (RS) model in NEUT. The effects of new (MK) model on T2K oscillation measurements shows bias on $\Delta^2_{23}$ and $\theta_{23}$. Although bias is small with respect to the uncertainty right now, clearly mis-modelling can produce biased oscillation parameters, and this will be a serious problem for next-generation experiments.