The sensitivity of the ICAL detector at India-based Neutrino Observatory to neutrino oscillation parameters

Abstract: The India-based Neutrino Observatory (INO) will host a 50 kt magnetized iron calorimeter (ICAL) detector that will be able to detect muon tracks and hadron showers produced by Charged-Current muon neutrino interactions in the detector. The ICAL experiment will be able to determine the precision of atmospheric neutrino mixing parameters and neutrino mass hierarchy using atmospheric muon neutrinos through earth matter effect. In this paper, we report on the sensitivity for the atmospheric neutrino mixing parameters ($\sin^{2}\theta_{23}$ and $|\Delta m^{2}_{32}|$) for the ICAL detector using the reconstructed neutrino energy and muon direction as observables. We apply realistic resolutions and efficiencies obtained by the ICAL collaboration with a GEANT4-based simulation to reconstruct neutrino energy and muon direction. Our study shows that using neutrino energy and muon direction as observables for a $\chi^{2}$ analysis, ICAL detector can measure $\sin^{2}\theta_{23}$ and $|\Delta m^{2}_{32}|$ with 13% and 4% uncertainties at 1$\sigma$ confidence level for 10 years of exposure.