Reconstruction Techniques used in the NOvA Experiment

NOvA is a long-baseline neutrino oscillation experiment that is designed to probe the neutrino mass hierarchy and mixing structure. It uses two functionally identical liquid scintillator detectors 14mrad off-axis from the NuMI beamline at Fermilab, allowing for a tightly focused neutrino flux peaked at around 2 GeV. The world-leading intensity of the NuMI beamline, over 700 kW, along with the very high cosmic background rate at its on-surface Far Detector, pose unique challenges in reconstructing single neutrino events separated from other physics interactions in the detector environment. Furthermore, one needs to estimate the energies and momenta of the products from neutrino interactions with high enough resolutions in order to measure oscillation parameters with high precision. To do this, NOvA leverages the detectors' excellent timing and spatial resolutions and employs a wide suite of techniques, both kinematic and deep-learning based, to reconstruct important physics information. In this talk, I will provide an overview of the reconstruction algorithms used in NOvA to address these and many other challenges.