Data-Driven Background Constraints for Electron Neutrino Appearance in the NOvA Oscillation Analysis

NOvA is a long baseline neutrino oscillation experiment, comprised of two functionally identical detectors, which measures electron neutrino appearance and muon neutrino disappearance at the Far Detector (FD) using neutrinos originating from the NuMI Beam at Fermilab. The Near Detector (ND) observes the highly pure muon neutrino or antineutrino NuMI beam before oscillations can occur, and provides us with a high statistics probe into understanding any misidentified events which could mimic our signal at the FD. This background to the electron neutrino appearance signal at the FD has three main components: charged current muon neutrino, neutral current, and charged current electron neutrino events. To accurately predict these FD background events, NOvA uses three different methods to obtain a data-driven correction to the background components at the ND and uses these ND constraints to estimate each of these at the FD. In my talk, I will present details of the background constraints and the extrapolation techniques for estimating the FD spectrum using both the neutrino and antineutrino dominated modes of the NuMI beam.