The relationship between theory and experiment is a symbiotic one, it shows that theory and experiment are not independent; instead, they continuously inform and challenge each other. Theoretical advancements suggest new experimental approaches and interpretations, while experimental results shape and sometimes redefine theoretical frameworks. This dynamic is evident in the collaborative nature of modern neutrino research, where extensive international collaborations pool resources and expertise to tackle the complexities of neutrino detection and analysis.
On the theoretical front, this thesis provides an in-depth comparison and analysis of various neutrino-nucleus interaction models, focusing on identifying physical observables sensitive to nuclear effects and model dependence. Aiming to understand the behavior of each model, the impact of its underlying assumptions on the distributions of physical observables, and the insights these distributions provide about the nuclear medium and its effect on the interaction. The models analyzed include the Relativistic Fermi Gas (RFG), Local Fermi Gas (LFG), Spectral Function (SF), Energy-Dependent Relativistic Mean Field (EDRMF), and Relativistic Plane-Wave Impulse Approximation (RPWIA) models. These models, each with different treatments of nuclear structure and interaction dynamics, are evaluated using a sample of Charged Current Quasielastic (CCQE) neutrino events on carbon-12, with one muon and one proton in the final state.
Further, the thesis introduces the novel approach of using the superscaling variable as an observable in neutrino-nucleus interactions that can be reconstructed experimentally, provided both final state particles are detected. We show that the superscaling variable can be a useful analysis tool, providing information about the removal energy of nucleons from the nucleus. Additionally, it aids in distinguishing between CCQE events that have undergone final state interactions and backgrounds originating from non-CCQE events that have a CCQE-like signature.
On the experimental front, the thesis leverages the Monte Carlo simulation of the T2K (Tokai to Kamioka) experiment's near detector (ND280) to provide experimental predictions, highlighting the impact of the detector's response and limitations on the distributions of observables, specifically the regions that were identified as model-dependent or sensitive to nuclear effects. The study concludes by discussing the implications of the ND280 detector's upgrade and the future prospects of incorporating advanced detection technologies in neutrino analyses.
This work not only enhances our understanding of neutrino-nucleus interactions but also guides future experimental and theoretical advancements in the field.
