Canadian Participation in the T2K Long Baseline Neutrino Experiment

这项提议支持加拿大非常成功地参与了T2K长基线实验，在该实验中，J-PARC加速器实验室产生了一束强烈的Muon(反)中微子束，并将其定向到295公里外的Super-Kamiokande探测器，以研究它们向中微子振荡引起的其他中微子的转变。加拿大成员是这项工作的创始成员，为实验的设计引入了基本要素，并为光学跃迁辐射探测器、细粒探测器和时间投影室等关键部件作出了贡献，这些部件构成了近距离探测器跟踪系统的核心。在TRIUMF和ComputeCanada的支持下，加拿大人提供了其他关键贡献，如用于近探测器工作的网络、慢速控制和数据库、大规模计算和数据访问、Super-Kamiokande的新重建框架以及束线维修和维护。T2K在研究中微子方面已经建立了良好的科学成就记录，包括发现了从Muon中微子到电子中微子的出现，最精确地测量了中微子混合角theta23，现在是中微子与反中微子振荡中不对称的最灵敏的探测器，这可能会提供为什么宇宙由物质主导的线索。这些科学问题是当今粒子物理学面临的最紧迫的问题之一。

This proposal supports the highly successful Canadian involvement in the T2K long baseline experiment, where an intense muon (anti)neutrino beam is produced at the J-PARC accelerator laboratory and directed 295 km away to the Super-Kamiokande detector to study their transition to other neutrino flavours arising from neutrino oscillations. Canadian members were founding members of the effort, introducing fundamental elements to the design of the experiment, and contributing key components such as the optical transition radiation detector, the fine-grained detectors and time projection chambers that form the core of the tracking system for the near detectors. With support from TRIUMF and ComputeCanada, Canadians provide other critical contributions such as the network, slow control, and databases for the near detector effort, large scale computing and data access, a new reconstruction framework for Super-Kamiokande, and beam line repair and maintenance. T2K has established strong track record of scientific achievements in the study of neutrinos including the discovery of the muon neutrino to electron neutrino appearance, the most precise measurements of the neutrino mixing angle theta23, and now the most sensitive probes of asymmetries in the neutrino vs. antineutrino oscillations which may provide clues on why the universe is matter-dominated. These scientific issues are among the most urgent facing particle physics today.