WoP-MMA: Multi-TeV, Multi-Messenger, and Multi-Wavelength Particle Astrophysics with HAWC

伽马射线是电磁辐射中能量最高的形式。对天体物理伽马射线的观测是对整个宇宙中最极端环境中的物理条件和过程的探测，可以用来测试基础物理学。高海拔水切伦科夫（HAWC）天文台位于墨西哥内格拉山脉的斜坡上，是一个地面设施，具有独特的观测高能伽马射线的能力。该奖项支持宾夕法尼亚州立大学的科学家利用HAWC天文台收集的数据进行研究。宾夕法尼亚州立大学小组最重要的成果是确定了我们银河系中观测到的最高能量源。这些物体可以将宇宙射线加速到比地球上人造粒子对撞机产生的任何粒子高十倍的能量。宾夕法尼亚州立大学还积极参与教育和外展活动。作为该计划的一部分，已经开发了一个在线数据存储库和显示器，使广大公众可以访问HAWC数据。HAWC天文台的两个非常显著的特点是连续观测和大视场，这对北方天空的多信使天体物理学至关重要。这使得HAWC对于探测来自扩展区域的高能伽马射线以及对三分之二的天空进行连续调查尤为重要。作为这些能力的一个例子，HAWC首次捕获了两颗快速旋转的恒星发出的高能光的广角视图。对这些恒星邻居的新视角使人们对地球附近神秘的过量粒子的一个可能起源产生了严重的怀疑，这些粒子的起源在过去十年中一直吸引着科学家。这些测量证明了HAWC天文台探测这种非常大的物体的能力。相对较近的星系天体，如这两颗脉冲星，看起来如此之大，以至于人们只能用视野较宽的仪器才能看到它们。来自HAWC天文台的数据为这些非常广泛的源提供了一个独特的和互补的视图，这是更尖锐的伽玛射线望远镜不可能做到的。HAWC在获奖项目中能力的另一个重要例子是继续寻找第一个银河系pevatron，一种能够将质子加速到PeV能量的宇宙射线加速器。最近对超新星遗迹G106.3+2.7、银河微类星体SS 433和HAWC发现的伽玛射线源HAWC J1825-134的观测表明，伽玛射线的光谱持续超过100 TeV。这意味着能量至少达到800 TeV的相对论性质子或能量至少达到270 TeV的相对论性电子的产生。HAWC天文台收集的数据使我们更接近于发现第一个宇宙pevatron并了解它们的性质。这个项目推进了NSF宇宙大构想窗口的目标。该奖项反映了美国国家科学基金会的法定使命，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。

Gamma-rays are the highest energy form of electromagnetic radiation. Observations of astrophysical gamma-rays serve as probes of physical conditions and processes in the most extreme environments throughout the Universe and can be used to test fundamental physics. The High Altitude Water Cherenkov (HAWC) observatory, located on the slopes of the Sierra Negra in Mexico, is a ground-based facility designed with unique capabilities to observe very high-energy gamma-rays. This award supports scientists at Pennsylvania State University doing research with data collected with the HAWC observatory. The most significant result from the Penn State group is the identification of the highest-energy sources ever observed in our Galaxy. These objects can accelerate cosmic rays to energies about ten times higher than any particles produced using man-made particle colliders on Earth. The Penn State group is also actively engaged in education and outreach activities. As part of this program, an online data repository and display has been developed that makes the HAWC data accessible to the broad public. Two very distinctive features of the HAWC Observatory are the continuous observations and the large field of view, which are vital to multi-messenger astrophysics of the northern sky. These make HAWC particularly important for the detection of very high energy gamma rays from extended regions and for the continuously survey of 2/3 of the sky. As an example of these capabilities, HAWC captured the first wide-angle view of very-high-energy light emanating from two rapidly spinning stars. The fresh perspective on these stellar neighbors casts serious doubt on one possible origin for a mysterious excess of particles near Earth whose origin has tantalized scientists in the last decade. These measurements demonstrate the capability of the HAWC observatory to detect such very extended objects. Relatively close galactic objects, like these two pulsars, appear so extended that one can only see them with an instrument with a wide field-of-view. Data from the HAWC observatory provides a unique and complementary view of these very extended sources that is not possible with the more pointed gamma-ray telescopes. Another important example of HAWC’s capabilities in the awarded program is the continued search for the first galactic PeVatrons, a cosmic-ray accelerator capable of accelerating protons to PeV energies. Recent observations of the gamma-ray emission from the supernova remnant G106.3+2.7, Galactic microquasar SS 433 and HAWC discovered a gamma-ray source- HAWC J1825-134 – indicate spectra that continue well past 100 TeV. This implies production by relativistic protons with energies up to at least 800 TeV, or by relativistic electrons with energies up to at least 270 TeV. The data collected with the HAWC observatory bring us significantly closer to finding the first cosmic PeVatrons and understanding their nature. 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.