Sensitivity of ORCA to the neutrino mass ordering and oscillation parameters

ORCA (Oscillations Research with Cosmics in the Abyss) is a megaton-scale Cherenkov neutrino detector currently under construction by the KM3NeT collaboration, at a depth of 2450m in the Mediterranean Sea. Atmospheric neutrinos cross the Earth along a wide range of baselines, undergoing matter effects which enhance neutrino oscillations in the few GeV energy range with a dependence on the neutrino mass ordering (NMO). The ORCA design consists of a dense configuration of multi-PMT optical modules, exploiting the excellent optical properties of deep seawater to reconstruct both cascade events (mostly νe {\nu_e} ) and track events (mostly νμ \nu_\mu ) down to a few GeV. ORCA is expected to measure the NMO with a median significance greater than 3σ \sigma after a few years of operation. This contribution focuses on the methods and results of the sensitivity studies for the measurement of the mass ordering as well as oscillation parameters (θ23 \theta_{23} , ΔM2 \Delta M^2 ).