Selecting Charged Current Muon Neutrino Interactions on Argon with the Short-Baseline Near Detector

Abstract

The uncertainties associated with neutrino-nucleus cross section modelling need to be reduced in order to measure neutrino oscillation parameters, the mass hierarchy and CP violation to a high degree of precision. SBND, a 112 ton liquid argon time projection chamber, will be the near detector of the short-baseline neutrino program at Fermilab. Once data taking begins in 2022, it will provide flux constraints for sterile neutrino searches and produce world leading neutrino-argon cross sections with up to seven million neutrino events in three years. This thesis describes the simulation, calibration and reconstruction tools developed to measure charged current muon neutrino interactions. Backgrounds from cosmic ray muons, neutrino interactions outside of the detector and different neutrino interaction channels were identified and removed as part of this process. The signal events were selected with purity of 90% and an efficiency of 67%, providing a strong starting point for measurements of exclusive channels. The expected statistical and systematic uncertainties on rate predictions and cross section measurements at the full 6.6×10 20 proton on target exposure were evaluated. i Gleb to show me all (three) of the nearby bars and give me unrealistic expectations about how cheaply I could buy a car. Living at site 56 with Andy, Rhiannon and (all to briefly) Jack was one of the highlights of my experience. My only regret was not getting to know Andy and Rhiannon better during my undergrad, who knew there were people that could make being trapped in a house in the middle of nowhere without working cars and running water and an outside temperature of-40 fun? Fermilab is full of great people and I'd especially like to thank the young MicroBooNErs for taking in your younger experimental siblings and letting us tag along to the taco Tuesday's, game nights and murder mysteries (I hope Lizzie is in a safe pair of hands). I would mention you all by name but that would probably take up another half a page, iii y'all know who you are. None of this work would have been possible without the tireless efforts of the SBND collaboration. Michelle showed me and Dom the ropes when we were both starting out and provided consistently excellent advice until the very end. Andrzej, Costas and Ornella all helped to guide my research with their helpful input and discussions. Gianluca and Vito, thanks for helping me keep sbndcode functioning over all of these years. I owe both Ed and Gray a pint for rerunning a production so I could get my thesis finished. The students and post-docs on SBND are second to none, Diego and Nicola taught me so much about hardware and were also just great people to be around. I couldn't end this without mentioning SBND's most valuable resource, Dom Brailsford. His endless patience and willingness to help students has me convinced he is either a saint or involved in a bet over who can get into the most acknowledgement sections.