Using charged particle test beams to constrain systematic uncertainties for the DUNE experiment

The existence of non-zero neutrino masses is the one unexplained feature of the Standard Model. As such, neutrinos warrant further investigation. The Deep Underground Neutrino Experiment (DUNE) is a long-baseline neutrino oscillation experiment currently in its construction phase. Upon completion it aims to resolve several questions regarding the properties of neutrinos by making precise measurements of muon neutrino disappearance and electron neutrino appearance at a baseline of 1300 km. Specifically, DUNE will aim to find evidence of Charge-Parity symmetry (CP) violation in the lepton sector and determine the ordering of the neutrino mass eigenstates (the neutrino mass hierarchy). In order to accomplish these goals, DUNE’s systematic uncertainties must be understood and it is this that is the primary subject of this thesis. Initially, studies are presented showing the effect of DUNE’s nominal systematic uncertainties on its sensitivity to CP violation and the neutrino mass hierarchy, where the importance of controlling the detector systematics is highlighted. Following this, methods of controlling systematics resulting from neutrino cross-sections are presented, both utilising a high pressure gas time projection chamber. This includes a novel method for producing a low energy proton beam for use in neutrino experiments. Finally, a measurement of the electron lifetime in the ProtoDUNE-SP detector is presented. This lifetime is compared to the values obtained from dedicated purity monitors and translated to an energy scale uncertainty. The effect of this uncertainty on DUNE’s measurement of the neutrino oscillation parameters is assessed