Neutrino oscillation at T2K and Hyper Kamiokande and development of the Hyper Kamiokande light injection calibration system

中微子振荡是粒子物理学标准模型或超越标准模型的物理学中的关键现象，但许多问题仍然没有答案。CP破坏阶段仍然难以捉摸，中微子质量等级的确切性质仍然未知。因此，超神冈（Hyper-K）实验，中微子物理学的一项主要努力，准备解开中微子振荡和CP破坏的奥秘。这项研究源于对中微子科学的精确性和创新性的日益增长的需求，因此Hyper-K旨在通过利用实验技术的进步来扩大我们对这些现象的理解，并为深入研究中微子振荡提供了独特的机会。这个雄心勃勃的项目建立在T2 K实验的成功基础上，将在塑造中微子物理学的未来方面发挥关键作用。该项目增强了我们对中微子振荡的理解，特别是专注于使用T2 K实验和Hyper-K数据寻找CP破坏。虽然T2 K已经取得了显着的进展，但需要更多的数据，升级的ND 280探测器和增加的光束功率才能达到最终的灵敏度。主要目的是开发和构建Hyper-K光注入校准系统的元件并分析其数据。通过这样做，我们打算填补我们的知识空白，并为这项研究的下一阶段铺平道路。该研究项目提出了一种双重方法来减少Hyper-K探测器系统中的系统性和适合T2 K实验的振荡。总体目标是通过最大限度地减少探测器系统学和数据分析产生的不确定性来提高实验的精度和准确性。第一部分旨在通过优化光注入系统并使用它来确定具有相关不确定性的detcor属性来提高Hyper-K探测器的性能。除了这个硬件工作，水切伦科夫模拟（WCSim）将被用来模拟探测器对中微子相互作用的响应。模拟事件将用于研究测量的探测器属性对测量信号的影响。本研究的第二部分旨在将改进的探测器系统学纳入T2 K和Hyper K实验的振荡拟合中。因此，T2 K振荡拟合将与更新的探测器系统升级，以提高中微子振荡测量的精度。将进行广泛的模拟和统计分析，以评估这些变化对拟合性能的影响。通过结合这两项研究工作，我们的目标是大大降低Hyper-K探测器的系统不确定性，并提高T2 K实验中中微子振荡测量的精度。总之，这个项目弥补了我们对中微子振荡和CP破坏的知识的差距。Hyper-K光注入系统的开发和建设，加上对增强T2 K数据的分析，将为粒子物理学领域做出重大贡献。理解CP破坏可能对我们理解物质-反物质不对称性和宇宙的演化产生深远的影响，使这项研究在更广泛的科学背景下具有至关重要的意义。

Neutrino oscillations are crucial phenomena in the Standard model of particle physics or specifically the physics beyond the Standard model, yet many questions remain unanswered. The CP-violating phase remains elusive, and the exact nature of neutrino mass hierarchy is still unknown. Thus, the Hyper Kamiokande (Hyper-K) experiment, a leading endeavour in neutrino physics, is poised to unlock the mysteries of neutrino oscillations and CP violation. This research stems from the ever-increasing need for precision and innovation in neutrino science and so Hyper-K aims to expand our understanding of these phenomena by leveraging advancements in experimental techniques and offers a unique opportunity to delve into neutrino oscillation studies. This ambitious project builds upon the success of the T2K experiment and will be pivotal in shaping the future of neutrino physics. This project enhances our understanding of neutrino oscillations, specifically focusing on the search for CP violation using the T2K experiment and Hyper-K data. While T2K has made remarkable progress, more data, an upgraded ND280 detector, and increased beam power are required to achieve ultimate sensitivity. The primary aim is to develop and construct elements of the Hyper-K light injection calibration system and analyse its data. By doing so, we intend to fill the gaps in our knowledge and pave the way for the next phase of this research. The research project presents a two-fold approach to reduce systematics in the Hyper-K detector systematics and the oscillation fit for the T2K experiment. The overarching goal is to improve the precision and accuracy of the experiments by minimising uncertainties stemming from both the detector systematics and the data analysis. The first part is aimed to enhance the performance of the Hyper-K detector by optimising the light injection system and using it to determine detcor properties with associated uncertainties. Alongside this hardware work, the Water Cherenkov Simulation (WCSim) will be employed to model the detector response to neutrino interactions. The simulated events will be used to study the impact of measured detector properties on the measured signals. The second part of this research aims to incorporate the improved detector systematics into the oscillation fit for the T2K and Hyper K experiments. Therefore, the T2K oscillation fit will be upgraded with the updated detector systematics to improve the precision of the neutrino oscillation measurements. Extensive simulations and statistical analyses will be conducted to assess the impact of these changes on the fit's performance. By combining these two research efforts, we aim to substantially reduce systematic uncertainties in the Hyper-K detector and improve the precision of neutrino oscillation measurements in the T2K experiment. In conclusion, this project bridges the gap in our knowledge of neutrino oscillations and CP violation. The development and construction of the Hyper-K light injection system, coupled with the analysis of enhanced T2K data, will contribute significantly to the field of particle physics. Understanding CP violation could have profound implications for our understanding of matter-antimatter asymmetry and the evolution of the universe, making this research critically significant in the broader context of science.