Development of a novel Kalman filter and its application to neutrino interaction measurements in next-generation time projection chambers

Thesis

The Deep Underground Neutrino Experiment (DUNE) is a next-generation neutrino oscillation experiment designed to achieve new levels of precision in the study of neutrino flavour oscillations. Its primary goals include measuring charge-parity violation in neutrinos and determining the neutrino mass hierarchy. To achieve these objectives, DUNE relies on a near detector complex to constrain systematic uncertainties, including those related to neutrino flux and interaction cross-sections. A key component of the near detector is a high-pressure gas time projection chamber called ND-GAr, whose novel application in neutrino physics enables low tracking thresholds and high precision, critical for addressing systematic uncertainties arising from nuclear effects. A novel momentum reconstruction algorithm, based on the Kalman filter technique, was developed for ND-GAr, facilitating the reconstruction of low energy tracks. This algorithm significantly improves the detector's performance in momentum reconstruction, eliminating bias and achieving a relative momentum resolution of approximately 2.6 % for muons and 5.3 % for protons. Its effectiveness was demonstrated through an evaluation of ND-GAr's performance in applying the transverse kinematic imbalance (TKI) technique. The double transverse kinematic imbalance, δpTT, can be used to isolate neutrino-hydrogen interactions, providing a sample free from nuclear effects. The novel Kalman filter enhances ND-GAr's ability to implement the TKI technique, achieving a δpTT resolution of (11.9 ± 0.7) MeV/c. These improvements will extend ND-GAr's capabilities in studying nuclear effects and will provide stronger support for DUNE's scientific goals.

Authors: Battisti, F

• DOI: 10.5287/ora-xqk206ggn
• Type of award: DPhil
• Level of award: Doctoral
• Awarding institution: University of Oxford
• Language: English
• Keywords: Kalman filter; neutrino interactions; accelerator neutrinos; particle tracking; nuclear effects; time projection chambers; neutrino oscillations; detector physics; neutrino physics
• Subjects: Neutrino interactions; Particle accelerators