Construction of the HAWC Gamma-Ray Observatory

该奖项将为墨西哥内格拉山脉高海拔水切伦科夫（HAWC）伽马射线天文台的建设提供资金。此处提供了建造 HAWC 的硬件、工程和合同（非科学家）劳动力的成本。 HAWC 的观测将探测宇宙中最极端的环境，为银河系及其他地区的非热过程提供独特的视角。 HAWC 的主要科学目标是： (a) 测量银河源最高能量的光谱； (b) 绘制从 1 TeV 到 100 TeV 的银河漫射伽马射线发射图，测量整个银河系的宇宙射线通量和光谱； (c) 研究活动星系核（AGN）的瞬态发射； (d) 监测天空中伽马射线爆发的 100 GeV 发射； (e) 利用 HAWC 的无偏天空巡天寻找新的 TeV 物理学。 HAWC 测量有可能揭示自然的基本对称性，包括寻找极端能量下的洛伦兹破坏、寻找宇宙中的暗物质以及直接探测大量遗迹粒子。HAWC 是一个由 250 个大型水箱组成的阵列，每个水箱底部都安装有三个光电倍增管 (PMT)。这些储罐的占地面积约为20,000平方米。探测器元件的探测范围扩大、高度增加和光学隔离使得灵敏度相对于 Milagro 提高了 15 倍，Milagro 进行了迄今为止最深的 TeV 天空广域观测。通过原型设计和在 HAWC 现场部署测试阵列，实现了设计和成本的改进。在整个开发过程中，成本估算和设计敏感性基本保持不变。目标是在阵列建设期间开始采集数据，并在大约三年内上线。这将使 HAWC 在费米任务正在进行时运行。 更广泛的影响：HAWC 是一种全天空仪器，其灵敏度将卫星发现的来源扩展到 TeV 能量的测量。 HAWC 将在 Milagro 强大的外展记录的基础上，将这一令人兴奋的研究领域带给学生和公众。由于 HAWC 是美国和墨西哥的联合项目，这将是吸引有才华的西班牙裔学生进入粒子天体物理学和一般物理学领域的绝佳机会。该小组制作了有关 HAWC 的宣传视频以及有关 HAWC 和粒子天体物理学的西班牙语和英语网络材料。

This award will provide funds for the construction of the High Altitude Water Cherenkov (HAWC) gamma-ray observatory to be built at Sierra Negra in Mexico. The costs for hardware, engineering, and contract (nonscientist) labor to build HAWC are being provided here. The observations of HAWC will probe the most extreme environments in the Universe, providing a unique view of non-thermal processes in the Galaxy and beyond. The key science goals of HAWC are to: (a) Measure the spectrum of Galactic sources to the highest energies; (b) Map the Galactic diffuse gamma-ray emission from 1 TeV to 100 TeV measuring the cosmic-ray flux and spectrum across the Galaxy; (c) Study transient emission from active galactic nuclei (AGN); (d) Monitor the sky for 100 GeV emission from gamma-ray bursts; and (e) Search for new TeV physics with HAWC's unbiased sky survey. HAWC measurements have the potential to shed light on the fundamental symmetries of nature, including the search for Lorentz violation at extreme energies, the search for the dark matter in the universe, and the direct detection of massive relic particles.HAWC is an array consisting of 250 large water tanks, each instrumented with three photomultiplier tubes (PMTs) mounted on the bottom of the tank. The tanks will cover an area of ~20,000 square meters. The expanded detection, increased altitude and optical isolation of the detector elements lead to a 15-fold increase in sensitivity relative to Milagro, which performed the deepest wide-field survey of the TeV sky to date. Refinement of the design and cost has been achieved through prototyping and deploying a test array at the HAWC site. The cost estimate and design sensitivity have stayed roughly constant through the development process. The goal is to begin taking data while the array is under construction and to be online within approximately three years. This will allow HAWC to run while the Fermi mission is ongoing.Broader Impacts: HAWC is an all-sky instrument that will have the sensitivity to extend the measurement of satellite-discovered sources to TeV energies. HAWC will build on the strong outreach record of Milagro to bring this exciting field of research to students and the general public. Since HAWC is a joint US-Mexican project, this will be an excellent opportunity to attract talented Hispanic students to the field of Particle Astrophysics and to Physics in general. The group has developed an outreach video about HAWC and web materials about HAWC and Particle Astrophysics in both Spanish and English.