Particle Astrophysics at Princeton: Solar Neutrino and Dark Matter Studies with Borexino and DarkSide

该奖项将为粒子天体物理学的两个实验项目提供支持：Borexino液体闪烁体探测器的太阳中微子和DarkSide-50液体氩气时间投影室（TPC）的暗物质。这个新生的暗物质项目将利用Borexino在20多年的研究中积累的低背景方法的专业知识和设备。DarkSide-50将利用Borexino计数测试设备（CTF）以及由Borexino合作在意大利Gran Sasso的地下实验室建造的闪烁体和水净化设备。虽然Borexino和DarkSide合作仍然是两个独立的实体，但几乎所有的Borexino团队都加入了DarkSide合作，并将同时参与这两项活动。Borexino是一个用来观测低能太阳中微子的探测器。它是最近投入使用的大型实时太阳中微子探测器，已经运行了三年多一点，在此期间它收集了太阳和地球上的中微子数据。太阳中微子的目标是将铍-7中微子的测量精度提高到不确定度小于5%，并首次对其他中微子分支进行实时测量，尤其是pep，可能还有pp和CNO中微子。DarkSide-50是一个50公斤的双相氩探测器，正在开发中，用于直接探测暗物质粒子。它旨在测试创新的低背景方法，以确保无背景操作。它将开创地下氩气用于暗物质研究的先河。它将被部署，封闭在液体闪烁体中子否决，在CTF水箱内。闪烁体-水组合屏蔽提供无背景操作的年曝光。就更广泛的影响而言，建议的活动将以多种方式推动科学和教育使命：(1)它将提供一个训练学生的绝佳机会，使他们有机会为基础科学和先进工程领域的前沿项目的成功作出贡献；(2)通过开发可应用于从国家安全到医学成像等领域的技术，使社会受益；(3)支持继续发展成功的e&o项目，如普林斯顿-阿布鲁佐-南达科他州高中生暑期学校。

This award will provide support for operations on two experimental initiatives in particle astrophysics: solar neutrinos with the Borexino liquid scintillator detector and dark matter with the DarkSide-50 liquid argon Time Projection Chamber (TPC). The nascent dark matter project will take advantage of the expertise in and facilities for low background methods accumulated by the Borexino collaboration in over two decades of research. DarkSide-50 will take advantage of the Borexino Counting Test Facility (CTF) and of the scintillator and water purification equipment built at the underground lab at Gran Sasso, Italy by the Borexino collaboration. While the Borexino and DarkSide collaborations remain two separate entities, almost all of the Borexino groups have joined the DarkSide Collaboration, and will work on both activities.Borexino is a detector designed to observe low-energy solar neutrinos. It is the most recent large-scale, real-time solar neutrino detector to become operational and has been in operation for a little more than three years, during which time it has acquired solar and terrestrial neutrino data. The solar neutrino goal is to improve the measurement of Beryllium-7 neutrinos to an uncertainty less than 5%, and to make the first real time measurements of other neutrino branches, especially the pep, and possibly also the pp and CNO neutrinos. DarkSide-50 is a 50-kg dual-phase argon detector under development for the direct detection of dark matter particles. It is designed to test innovative low background methods to ensure background-free operation. It will initiate the use of underground argon for dark matter applications. It will be deployed, enclosed in a liquid scintillator neutron veto, within the CTF water tank. The scintillator-water combined shield provides background-free operation for ton-year exposures.For Broader Impacts, the proposed activity will advance the scientific and educational mission in a variety of ways: (1) it will offer an excellent opportunity for the training of students, who will have a chance to contribute to the success of a cutting edge project in fundamental science and advanced engineering; (2) it will benefit society by developing techniques that could find application in areas ranging from national security to medical imaging; and (3) it will support continued development of successful E&O programs such as the Princeton-Abruzzo-South Dakota summer school for high school students.