Data Fitter of Neutrino Oscillation Experiments in the GNA Software

Although neutrino physics has been actively developing for a last few decades some questions are still not answered. One of urgent tasks is to measure neutrino oscillation parameters such as the charge-parity phase $${{\delta }_{{{\text{CP}}}}}$$ , the neutrino mass ordering, and the octant of the mixing angle $${{\theta }_{{{\text{23}}}}}$$ . One of the ways to reach a high significant level for these values is to combine data taken from various experiments. Currently operating neutrino accelerator experiments, NOvA and T2K, have been detecting neutrino interactions in electron (anti)neutrino appearance and muon (anti)neutrino disappearance modes, and nowadays these data are the main source of information to estimate unknown neutrino oscillation parameters. The data fitter of accelerator neutrino experiments is created within the GNA software and 2D contours of individual and combined sensitivities to $$\Delta m_{{{\text{32}}}}^{{\text{2}}},\;{{\delta }_{{{\text{CP}}}}}$$ and $${{\sin }^{2}}{{\theta }_{{{\text{23}}}}}$$ for NOvA and T2K experiments are plotted based on Monte-Carlo simulation and Asimov data.