SNO+ Initial Construction and Continued Development

加拿大世界领先的中微子物理设施萨德伯里中微子天文台正在开发一项新的实验。 该实验被称为SNO+，它包括在2007年SNO中的重水被移除后，用液体闪烁体填充SNO探测器。 通过将SNO转变为SNO+，将创建一个具有不同科学目标的多用途实验。 SNO+将能够解决粒子物理学、微物理学和天体物理学中的基本问题。 SNO+将从SNO结束的地方开始，它将扩展我们对中微子及其对物理宇宙影响的理解。与水中的中微子相互作用相比，当中微子在液体闪烁体中相互作用时，液体闪烁体发出的光要多100倍。 这意味着SNO+将能够探测到能量较低的中微子。 可以研究来自太阳的低能量中微子。 另外，还将观测地球天然放射性产生的反中微子。 通过这样做，SNO+将能够测定地球深处的放射性总量。 地球热量中来自放射性的部分是一个可以回答的基本问题。通过将钕装入液体闪烁体中，可以在SNO+中研究一种极其罕见的核衰变。 这一过程被称为无中微子双β衰变，对它的观测将揭示中微子的基本性质，并对我们理解宇宙中的物质和反物质产生潜在影响。SNO+自2005年4月以来一直在进行研究与开发，由NSERC资助。 在项目开发的这一点上，SNO+已经准备好实施。 我们已准备好推进初步建设和持续发展，该提案要求提供资金，以开始将SNO转换为SNO+。

A new experiment is being developed at the Sudbury Neutrino Observatory, Canada's world-leading neutrino physics facility.  The experiment is called SNO+ and it consists of filling the SNO detector with liquid scintillator after the heavy water currently in SNO is removed in 2007.  By turning SNO into SNO+, a multipurpose experiment with diverse scientific goals would be created.  SNO+ will be able to address fundamental questions in particle physics, in geophysics, and in astrophysics.  SNO+ will start where SNO leaves off and it will stretch our understanding of the neutrino and its impact on the physical universe.A liquid scintillator emits 100 times more light when a neutrino interacts in it compared to a neutrino interaction in water.  This means that SNO+ will be able to detect neutrinos with lower energies.  Lower energy neutrinos from the Sun could be studied.  Separately, antineutrinos from natural radioactivity in the Earth will be observed.  By doing this SNO+ will be able to assay the total amount of radioactivity in the deep Earth.  The fraction of Earth's heat that originates from radioactivity is a fundamental question that could be answered.An extremely rare nuclear decay might be studied in SNO+ by loading neodymium into the liquid scintillator.  Observation of this process, known as neutrinoless double beta decay, would shed light on the fundamental nature of the neutrino with potential impact on our understanding of matter and antimatter in the Universe.SNO+ has been conducting R&D, funded by NSERC since April 2005.  At this point in the development of the project, SNO+ is ready for implementation.  We are ready to move forward with initial construction and continued development and this proposal requests funding to begin converting SNO to SNO+.