Bychkov, Vladimir2018-11-282018-11-282018-08https://hdl.handle.net/11299/201067University of Minnesota Ph.D. dissertation August . 2018. Major: Physics. Advisor: Gregory Pawloski. 1 computer file (PDF); xiii, 137 pages.The NuMI Off-axis νe Appearance (NOvA) experiment studies neutrino oscillations in the NuMI (Neutrinos at the Main Injector) beam. The goal of the experiment is to determine the mass hierarchy and measure δCP , however it is also sensitive to sin2 θ23, and ∆m232. The present work tries to improve experimental sensitivity to the oscillation parameters by considering neutrino events which are discarded by the previous analysis — escaping events. The biggest issues with the escaping sample are significant cosmic background and correct energy estimation. Both issues were addressed and inclusion of escaping sample to the final fit led to an effective increase of statistics by 4% with best-fit measurements of sin2 θ23 = 0.504 and ∆m232 = 2.45 × 10−3 eV2.enmuon neutrino disappearanceneutrino oscillationneutrino physicsNOvAThesis or Dissertation