Solar Modulation of the Cosmic Ray Intensity and the Measurement of the Cerenkov Reemission in NOvA’s Liquid Scintillator

The NOνA (NuMI Off-axis electron neutrino Appearance) experiment is a long baseline neutrino oscillation experiment at Fermi National Accelerator Laboratory. Its purpose is to observe the oscillation of ν_μ (muon neutrino) to ν_e (electron neutrino) and to investigate the neutrino mass hierarchy and CP violation in the neutrino sector. Two detectors have been built for this purpose, a Near Detector 300 feet underground at Fermilab, and a Far Detector, on the surface at Ash River, Minnesota.

The completion of NOνA’s Far Detector in October 2014 enabled not only the recent measurement of neutrino oscillations, but an array of other physics studies. Coronal mass ejections cause an observable effect on the cosmic ray intensity measured at and around Earth, through the enhancement of the interplanetary magnetic field. Studying this phenomenon generally entails the measurement of the change in intensity of secondary neutrons from air showers, but it is of equal interest to observe the effects on secondary muons. Presented here is the study of the intensity modulation as measured in cosmic muon data from NOνA’s Far Detector in Ash River, MN. In addition, this thesis details the study of the non-linear energy response of NOνA’s liquid scintillator through the measurement of Cerenkov reemission, providing a needed correction to NOνA’s energy calibration.