Non-Accelerator Physics with The Super-Kamiokande Detector

该奖项将为该小组在日本神冈实验室的非加速器物理计划提供支持，并使用Super-Kamiokande（Super-K）探测器。自1996年以来，Super-K一直是天体物理学探测器的一个主要例子，用于帮助理解中微子的性质和寻找质子衰变。通过目前的升级，它现在正准备用大气中微子精确确定中微子振荡参数。大气中微子也提供了一个机会来了解各种中微子口味的相对质量，并且对所谓的电荷宇称（CP）破坏阶段很敏感，这可以帮助确定为什么宇宙中的物质比反物质多得多。该奖项还将支持观测其他类型的中微子相互作用的可能性，从而将暗物质的间接搜索扩展到中等/低质量的暗物质。神冈实验室有一个广泛的计划，让公众、本科生和K-12学生参与这项研究的兴奋。在新系统上工作的研究生将被整合到这些活动中，并讲授来自于Super-K中天体粒子物理学的物理学。每年夏天，该组织都会挑选UCI的本科生和高中生到UCI或日本工作。加州COSMOS计划为高中生提供住宿学术体验，其使命是激发新一代未来科学家，工程师和数学家的最具创造力的头脑。UCI教师创建课程“集群”的主题从天体物理学到数学建模海洋生态系统只是为了宇宙。在这里，他们建议在实验粒子物理学中发起一个集群，强调检测技术。之前的NSF资助支持设计，建造和安装一个新的触发系统，宽带智能触发（WIT）系统，该系统完全处理未触发的原始流中的所有数据，并以2.49 MeV的高效率提取电子，Super-K稳定可靠的事件重建极限。UCI集团将利用上一个奖项的投资，并在WIT数据分析方面处于领先地位。目前正在对超级K进行升级，增加钆，以提高其中子探测能力。目前，中子是通过在大约200微秒后从氢上捕获发射的2.2 MeV光子来观察的。平均只有7个探测到的光子，探测效率相当低。在溶解0.2%的Gd 2（SO 4）3之后，90%的中子将捕获在Gd上，这产生8 MeV的伽马级联，并且在约35微秒之后每次捕获产生约22个检测到的光子。高效率的中子探测将对超K-Gd中的许多物理问题产生积极的影响。 该项目推进了NSF宇宙大创意窗口的目标。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This award will provide support for the group’s non-accelerator physics program at the Kamioka Laboratory in Japan with the Super-Kamiokande (Super-K) detector. Super-K has been a prime example of an astrophysics detector searching to help understand the properties of neutrinos and the search for proton decay since 1996. With the current upgrade, it is now preparing to precisely determine neutrino oscillation parameters with atmospheric neutrinos. Atmospheric neutrinos also provide an opportunity to understand the relative masses of the various neutrino flavors and are sensitive to the so-called Charge-Parity (CP)-violation phase, which could help identify why there is so much more matter than anti-matter in the Universe. This award will also support the possibility of observing other types of neutrino interactions that will extend the indirect search for dark matter to medium/low Dark Matter masses.The Kamioka Laboratory has an extensive program for involving the public, undergraduate students, and K-12 students in the excitement of this research. The graduate student working on the new system will be integrated into these activities and lecture on the physics that comes from looking at astroparticle physics in Super-K. Each summer, the group selects undergraduate students from UCI and high school students to work at UCI or in Japan. The State of California COSMOS program provides a residential academic experience for high school students with a mission to motivate the most creative minds of the new generation of prospective scientists, engineers, and mathematicians. UCI faculty create course “clusters” in topics from astrophysics to mathematical modeling to marine ecosystems just for COSMOS. Here, they propose to originate a cluster in experimental particle physics emphasizing detection techniques.A previous NSF grant supported the design, construction and installation of a new trigger system, the Wideband Intelligent Trigger (WIT) system, which completely processes all of the data in the un-triggered, raw stream and extracts electrons with high efficiency down 2.49 MeV, the limit of stable and reliable event reconstruction at Super-K. The UCI group will capitalize on the investment of the previous award and take the lead in WIT data analysis. Super-K is currently in the process of being upgraded with the addition of gadolinium in order to enhance its neutron detection capabilities. At present, neutrons are observed by the 2.2 MeV photon emitted from capture on Hydrogen after about 200 micro-sec. On average there are only seven detected photons and the detection efficiency is quite low. After dissolving 0.2% Gd2(SO4)3, 90% of the neutrons will capture on Gd which makes an 8 MeV gamma cascade and produces about 22 detected photons per capture after about 35 micro-sec. High efficiency neutron detection will benefit many physics topics in Super-K-Gd. This project advances the goals of the NSF Windows on the Universe Big Idea.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.