Neutrino Oscillation parameter determination at INO-ICAL using track and hit information from GEANT

Abstract: We study the capability of INO-ICAL to determine the atmospheric neutrino oscillation parameters $|\Delta m^2_{31}|$ and $\sin^2 \theta_{23}$. We do not use any generator level information. Instead, we process the generated atmospheric neutrino events through GEANT4 simulation of the detector and the event reconstruction framework. Among the outputs of this framework, only the momentum and direction of the longest track were used in a previous study by other authors. In this study, in addition to these variables, we consider a third variable based on additional hits, which arise due to hadrons in the event. We show that the inclusion of the this variable leads to a 30% reduction in the uncertainties of $|\Delta m^2_{31}|$ for a 5-year run of ICAL. We find that doubling the exposure time leads to a 30% reduction in the uncertainties of both $|\Delta m^2_{31}|$ and $\sin^2 \theta_{23}$.