Proposal to Operate and Analyze Data from the High Resolution Fly's Eye Detector (Part IV)

这是一份请求资金继续运行位于美国陆军犹他州杜格威试验场的高分辨率苍蝇眼（HiRes）天文台的提案。该探测器由两个相距12.6公里的观测站组成，它们通过大气中的氮荧光探测超高能宇宙射线。实验目的是研究从1018ev到1020ev以上的宇宙射线的光谱、组成和各向异性。先前的实验已经证明，光谱继续超过预测的Greisen-Zatsepin-Kuzmin （GZK）截止。截止点以上事件的性质是一个谜，激发了许多理论推测。单目HiRes数据有力地证实了立体Fly’s Eye在3x1018 eV观测到的倾斜结构，以及GZK截止能量附近光谱的硬化。在1020ev以上观测到一些突出的事件。倾角结构的位置和1020ev以上的事件通量都与AGASA地面阵列公布的结果存在显著差异。本提案描述了该探测器的额外操作将如何解决这些和其他突出问题。HiRes开发了一个名为ASPIRE的积极的教育推广项目。该项目是与犹他州教育办公室合作进行的，向公众传达了HiRes科学研究的兴奋之情。该合作组织建议继续这一成功的外联努力。

This is a proposal requesting funds to continue to operate the High Resolution Fly's Eye (HiRes) Observatory located on the U.S. Army's Dugway Proving Ground, Utah. The detector is comprised of two stations, separated by 12.6 km, which detect ultra high-energy cosmic rays via nitrogen fluorescence in the atmosphere. The goals of the experiment are to study the spectrum, composition, and anisotropy of cosmic rays starting from 1018 eV to beyond 1020 eV. Previous experiments have shown evidence that the spectrum continues past the predicted Greisen-Zatsepin-Kuzmin (GZK) cutoff. The nature of the events above the cutoff is a puzzle and has stimulated much theoretical speculation. Monocular HiRes data strongly confirm the dip structure observed by the stereo Fly's Eye at 3x1018 eV and the hardening of the spectrum around the GZK cut-off energy. A few outstanding events are observed above 1020 eV. Both the location of the dip structure and the flux of events above 1020 eV are in significant disagreement with published results from the AGASA ground array. This proposal describes how the additional operation of this detector will resolve these and other outstanding issues. HiRes has developed a vigorous educational outreach program, called ASPIRE. This project, conducted in collaboration with the Utah State Office of Education, communicates the excitement of the HiRes scientific research to the general public. The collaboration proposes to continue this successful outreach effort.