SNO+ Data Taking and Operations: Years 1-2

SNO+是萨德伯里中微子天文台（SNO）的后续实验。液体闪烁体将取代SNO探测器中的重水。通过这样做，将实现在较低能量下具有扩展灵敏度的新实验。SNO+将能够解决粒子物理学、地球科学和天体物理学中的基本问题。SNO+将从SNO停止的地方开始，并将扩大我们对中微子及其对宇宙演化的影响的理解。与水中相比，当中微子在液体闪烁体中相互作用时，液体闪烁体发射的光要多50倍。因此，SNO+将能够探测到比SNO能量更低的中微子。来自太阳的低能中微子将被研究，以揭示中微子的性质和恒星中的能量产生过程。另外，来自地球天然放射性的地球中微子将被SNO+探测到。探测到的地球中微子的数量可以与地球深部的放射性总量及其在地球热过程和历史中的作用有关。来自附近核能反应堆的反中微子将被用来测量控制中微子振荡现象的参数。最后，还将通过在液体闪烁体中分散碲来研究SNO+中极其罕见的核衰变。对这个过程的观测，被称为无中微子双β衰变（130 Te），将告诉物理学家中微子的物质-反物质性质，以及它与宇宙中物质和反物质的宇宙学问题的联系。基本对称性和与高能尺度物理学的联系也都与双β衰变有关。因此，对无中微子双β衰变的实验研究被认为是当今核物理和粒子物理最重要的研究课题之一。SNO+探测器和处理系统的建设已接近完成。调试、操作和数据采集将很快开始。2016年初，探测器将完全充满水。充水SNO+的数据将用于研究探测器光学和背景，并完成电子/数据采集调试。闪烁体净化厂的试运行将同时进行。2016年晚些时候，闪烁体工厂和SNO+探测器将准备好接收和纯化液体闪烁体。加拿大将进行强有力的分析工作，从第一批SNO+数据中提取物理结果。本提案要求资金支持：HQP、差旅以及与SNO+调试、数据采集、碲液体闪烁体材料处理和早期物理研究相关的材料和用品。此外，需要并正在申请资金，以支持现场SNO+操作（例如，检测器管理员、分析技术员、工厂操作员）。

SNO+ is the follow-up experiment to the Sudbury Neutrino Observatory (SNO). Liquid scintillator will replace the heavy water that was in the SNO detector. By doing so, a new experiment with extended sensitivity at lower energies will be realized. SNO+ will be able to address fundamental questions in particle physics, in geosciences, and in astrophysics. SNO+ will start where SNO left off and will expand our understanding of the neutrino and its impact on the evolution of the Universe.A liquid scintillator emits over 50 times more light when a neutrino interacts in it compared to in water. Consequently SNO+ will be able to detect neutrinos with lower energies than SNO. Lower energy neutrinos from the Sun will be studied to shed light on the properties of neutrinos and the energy generation processes in stars. Separately, geo neutrinos from natural radioactivity in the Earth will be detected by SNO+. The quantity of geo neutrinos detected can be related to the total amount of radioactivity in the deep Earth and its role in Earth's thermal processes and history. Antineutrinos from nearby nuclear power reactors will be used to measure the parameters that govern the phenomenon of neutrino oscillations. Finally, an extremely rare nuclear decay will also be studied in SNO+ by dispersing tellurium in the liquid scintillator. Observation of this process, known as neutrinoless double beta decay (of 130Te), would tell physicists about the matter-antimatter properties of the neutrino, and its connection to cosmological questions about matter and antimatter in the Universe. Fundamental symmetries and a connection to physics at higher energy scales are also both related to double beta decay. Hence, the experimental search for neutrinoless double beta decay is considered one of the most important pursuits in nuclear and particle physics today.SNO+ detector and process systems construction is nearing completion. Commissioning, operations and data taking will soon begin. In early 2016, the detector will be completely filled with water. Data from water-filled SNO+ will be used to study detector optics and backgrounds, and to complete electronics/data acquisition commissioning. The commissioning of the scintillator purification plant will take place concurrently. Later in 2016, the scintillator plant and the SNO+ detector will be ready to receive and purify liquid scintillator. There will be a strong Canadian analysis effort that will extract physics results from the first SNO+ data. This proposal requests funds to support: HQP, travel, and materials and supplies related to SNO+ commissioning, data taking, tellurium liquid scintillator materials processing, and early physics studies. In addition, funds to support SNO+ operations at site (e.g. Detector Manager, assay technicians, plant operators) are required and are being requested.