This book is based on the author's work in the T2K long-baseline neutrino oscillation experiment, in which neutrinos are generated by a proton beam and are detected by near and far neutrino detectors. In order to achieve the precise measurement of the neutrino oscillation, an accurate understanding of the neutrino beam and the neutrino interaction is essential. Thus, the author measured the neutrino beam properties and the neutrino interaction cross sections using a near neutrino detector called INGRID and promoted a better understanding of them. Then, the author performed a neutrino oscillation analysis using the neutrino beam and neutrino interaction models verified by the INGRID measurements. As a result, some values of the neutrino CP phase are disfavored at the 90% confidence level. If the measurement precision is further improved, we may be able to discover the finite CP phase which involves the CP violation. Thus, this result is an important step towards the discovery of CP violation in the lepton sector, which may be the key to understanding the origin of the matter–antimatter asymmetry in the universe.

This book reviews the status of a very exciting field OCo neutrino oscillations OCo at a very important time. The fact that neutrinos have mass has only been proved in the last few years and the acceptance of that fact has opened up a whole new area of study to understand the fundamental parameters of the mixing matrix. The book summarizes the results from all the experiments which have played a role in the measurement of neutrino oscillations and briefly describes the scope of some new planned experiments. Contributions include a theoretical introduction by Stephen Parke from FNAL, as well as articles from all the major experimental groups who have been pivotal in uncovering the nature of the neutrino mass. Sample Chapter(s). Chapter 1: Neutrino Oscillation Phenomenology (677 KB). Contents: Neutrino Oscillation Phenomenology (S J Parke); The Super-Kamiokande Experiment (C W Walter); Sudbury Neutrino Observatory (S J M Peeters & J R Wilson); Neutrino Oscillation Physics with KamLAND: Reactor Antineutrinos and Beyond (K M Heeger); K2K: KEK to Kamioka Long-Baseline Neutrino Oscillation Experiment (R J Wilkes); MINOS (P Vahle); The LSND and KARMEN Neutrino Oscillation Experiments (W C Louis); MiniBooNE (S J Brice); The OPERA Experiment in the CNGS Beam (D Autiero et al.); The T2K Experiment (D L Wark); The NO?A Experiment (G J Feldman); Double Chooz (G A Horton-Smith & T Lasserre); Daya Bay: A Sensitive Determination of ? 13 with Reactor Antineutrinos (K B Luk & Y Wang). Readership: Physicists, researchers and graduate students in high energy/nuclear and particle physics."

This thesis reports the measurement of muon neutrino and antineutrino disappearance and electron neutrino and antineutrino appearance in a muon neutrino and antineutrino beam using the T2K experiment. It describes a result in neutrino physics that is a pioneering indication of charge-parity (CP) violation in neutrino oscillation; the first to be obtained from a single experiment. Neutrinos are some of the most abundant—but elusive—particles in the universe, and may provide a promising place to look for a potential solution to the puzzle of matter/antimatter imbalance in the observable universe. It has been firmly established that neutrinos can change flavour (or ‘oscillate’), as recognised by the 2015 Nobel Prize. The theory of neutrino oscillation allows for neutrinos and antineutrinos to oscillate differently (CP violation), and may provide insights into why our universe is matter-dominated. Bayesian statistical methods, including the Markov Chain Monte Carlo fitting technique, are used to simultaneously optimise several hundred systematic parameters describing detector, beam, and neutrino interaction uncertainties as well as the six oscillation parameters.

Many experiments have provided evidence for neutrino flavor oscillations, and consequently that neutrinos are in fact massive which is not predicted by the Standard Model. Many experiments have been built to constrain the parameters which determine flavor oscillations, and for only three flavors of neutrinos the mixing parameters are well known, aside from the CP violating phase for two mass hierarchies. Most experimental data can be well explained by mixing between three flavors of neutrinos, however oscillation anomalies from several experiments, most notably from LSND (Liquid Scintillator Neutrino Detector) have suggested that there may be additional flavors of neutrinos beyond those in the Standard Model. One of the focuses of this dissertation is the possibility of adding new flavors of right-handed neutrinos to the Standard Model to account for oscillation anomalies, and exploring the consequences of sterile neutrinos for other experiments.Sensitivities to a particular model of sterile neutrinos at the future Long-Baseline Neutrino Experiment will be determined, in which CP effects introduced by the sterile neutrinos play an important role. It will be demonstrated how, by combining data from the Long-Baseline Neutrino Experiment along with data from Daya Bay and T2K, it is possible to provide evidence for or rule out this model of sterile neutrinos.A chi-squared analysis is used to determine the significance of measuring the effects of sterile neutrinos in IceCube; it will be shown that it may be possible to extract evidence for sterile neutrinos from high energy atmospheric neutrinos in IceCube. Furthermore it will be demonstrated how measuring neutrino flavor ratios from astrophysical sources in IceCube can help to distinguish between the three flavor scenario and a beyond the Standard Model (BSM) scenario involving sterile neutrinos. Measuring astrophysical as well as atmospheric neutrinos can evince the existence of sterile neutrinos.Despite the fact that the mixing parameters for the three Standard Model neutrino flavors are well known, some implications of neutrino interactions for flavor oscillations are not well understood. Neutrinos can interact with one another in a similar way to how neutrinos interact with normal matter. Neutrino-neutrino forward scattering can lead to a flavor swap for the propagating neutrino, or the propagating neutrino can retain its original flavor. These interactions contribute an effective potential to the Hamiltonian describing the flavor evolution which depends on a background neutrino density. In normal matter the neutrino density is very low which allows for neutrino-neutrino interactions to be ignored, however these interactions can dominate over vacuum and normal matter interactions in very dense environments such as core-collapse supernovae and early universe scenarios.Neutrino-neutrino interactions give rise to terms quadratic in neutrino densities in the equations of motion, and can give rise to what is called collective oscillations resulting from interference with vacuum and normal matter effects. The non-linearity has made the problem of solving for collective oscillations analytically intractable without simplifying assumptions, and has made this a problem relegated to supercomputer simulations. This dissertation is concerned with analytic methods for solving the equations of motion for core-collapse neutrino propagation. It will be shown here that, by keeping only $\nu\nu$-interactions at initial distances outward from the supernova core, it is possible to solve the equations of motion by factorizing vacuum oscillations and the effects of $\nu\nu$-interactions. Furthermore, it will be shown how using this factorization scheme it is possible to predict where flavor oscillations become unstable. This is an important development because it can allow one to predict the neutrino flux in Earth experiments from core-collapse supernovae, while at the same time gaining an understanding of the underlying physics involved in complicated processes such as collective oscillations and the rapid growth of oscillations at medium range distances. Using the factorization ansatz together with a measured supernova spectrum it is possible in principle to determine the thermal spectra inside of the supernova.

Neutrino oscillation (N.O.) is the only firm evidence of the physics beyond the Standard Model of particle physics and is one of the hottest topics in elementary particle physics today. This book focuses on the N.O., from its history to the future prospects, from the basic theories to the experiments. Various phenomena of N.O. are described intuitively with thorough explanations of the fundamental physics behind well-known formulations. For example, while many textbooks start with a discussion of the mixing matrix, this book stresses that N.O. is caused by the transition amplitudes between different neutrino flavors, and that the purpose of N.O. experiments is to measure transition amplitudes and think of its origin. The current understanding of neutrino oscillation is also summarized using the most up-to-date measurements, including the recently measured neutrino mixing angle θ13, and the future prospects of N.O. studies are described as well. The level of this book makes it a bridge between introductory textbooks and scientific papers.

The study of neutrino interactions and propagation has produced evidence for physics beyond the standard model and promises to continue to shed light on rare phenomena. Since the discovery of neutrino oscillations in the late 1990s there have been rapid advances in establishing the three flavor paradigm of neutrino oscillations. The 2012 discovery of a large value for the last unmeasured missing angle has opened the way for future experiments to search for charge-parity symmetry violation in the lepton sector. This thesis presents an analysis of the future sensitivity to neutrino oscillations in the three flavor paradigm for the T2K, NO A, LBNE, and T2HK experiments. The theory of the three flavor paradigm is explained and the methods to use these theoretical predictions to design long baseline neutrino experiments are described. The sensitivity to the oscillation parameters for each experiment is presented with a particular focus on the search for CP violation and the measurement of the neutrino mass hierarchy. The variations of these sensitivities with statistical considerations and experimental design optimizations taken into account are explored. The effects of systematic uncertainties in the neutrino flux, interaction, and detection predictions are also considered by incorporating more advanced simulations inputs from the LBNE experiment.