Revisiting the T2K data using different models for the neutrino-nucleus cross sections

TL;DR

This paper reanalyzes T2K neutrino oscillation data using alternative models for neutrino-nucleus interactions, revealing that the choice of cross section model influences the inferred oscillation parameters.

Contribution

It introduces a fit to T2K data incorporating multinucleon emission models, highlighting the impact of nuclear modeling on oscillation parameter determination.

Findings

Allowed regions in parameter space are affected by the choice of cross section model.

Best fit points shift when using multinucleon emission models.

Model choice influences the interpretation of neutrino oscillation data.

Abstract

We present a three-flavour fit to the recent \nu\mu --> \nu e and \nu\mu --> \nu\mu T2K oscillation data with different models for the neutrino-nucleus cross section. We show that, even for a limited statistics, the allowed regions and best fit points in the (\theta_{13},\delta_{CP}) and (\theta_{23},\Delta m^2_{atm}) planes are affected if, instead of using the Fermi Gas model to describe the quasielastic cross section, we employ a model including the multinucleon emission channel.