Operation of the Telescope Array, TALE, and the TAx4 Expansion by the University of Utah

望远镜阵列（TA）是北方半球最大的超高能宇宙射线（UHECR）探测器。 TAx4是目前正在进行的一项扩展，它将使地面探测器（SD）的数量增加一倍，由于SD的部署可以沿着操作，到2025年，TA将使现有的数据集增加两倍。 该奖项支持犹他州的宇宙射线物理组运行望远镜阵列（TA）复合体一年，包括低能扩展（TALE）和TAx 4。 这包括管理、工程和技术人员的努力和费用。 与往年相比，这意味着支助水平有所降低，这将减少收集数据的夜晚数，并减少网站和设备维护的数量。 日本和韩国的合作伙伴将集中精力建造和部署剩余的SD部队，并维护新的SD联队。 犹他州的工作人员全权负责设施维护、人员配备、观察班次和处理数据，并遵守土地管理局的土地使用法规。 TA支持辅助和测试实验，最近主持了一个闪电测绘阵列。 ASPIRE项目是TA的公共教育和外展部门，每年接受数百万次在线访问。 TA最近的令人兴奋的结果清楚地表明，需要从扩大的实验中获得更多的数据。 结果之一是明显存在一个“热点”，可能具有奇怪的性质，例如不同的，明显依赖于位置的宇宙射线（CR）光谱。 另一个是在最高能量下，由TA和皮埃尔·俄歇天文台（Pierre Auger Observatory）测量的光谱和CR成分之间的明显差异，皮埃尔·俄歇天文台是南半球最大的UHECR探测器。 从长远来看，将TA数据量增加两倍将有助于澄清这些比较，因此持续的TA操作非常重要。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。

The Telescope Array (TA) is the largest detector of ultra-high-energy cosmic rays (UHECR) in the northern hemisphere. TAx4 is an expansion currently under way which will double the number of surface detectors (SD), and since SD deployment can occur along with operations, by 2025 TA will have tripled the existing data set. This award supports the cosmic ray physics group at Utah for one year of running the Telescope Array (TA) complex, including the Low Energy Extension (TALE) and TAx4. This covers managerial, engineering and technical staff effort and expenses. This constitutes a somewhat lower level of support compared to past years, which will reduce the number of nights of collecting data, and provide for a smaller amount of site and equipment maintenance. The Japanese and Korean partners will concentrate on construction and deployment of the remaining SD units, and maintenance of the new SD wings. The Utah staff have sole responsibility for facility maintenance, staffing observing shifts and handling data, and maintaining compliance with Bureau of Land Management land use regulations. TA supports auxiliary and test experiments, recently hosting a lightning mapping array. The ASPIRE project is the TA’s public education and outreach arm, receiving millions of online visits each year. Direct outreach also reaches tens of thousands of teachers and students.Recent exciting results from TA clearly demonstrate the need for more data from an enlarged experiment. One result is the apparent existence of a “hotspot” with possibly curious properties, such as a different, and apparently position-dependent, cosmic ray (CR) spectrum. Another is the apparent discrepancy between spectra and CR composition at the highest energies as measured by TA and by the Pierre Auger Observatory, the largest UHECR detector but in the southern hemisphere. In the longer term, tripling the amount of TA data will help to clarify these comparisons, and continuing TA operations is therefore very important.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.