Fast Transients and Furious Spectroscopy: Revealing the High-Speed Sky with Argus Pathfinder

新的传感器技术和大规模生产的光学系统将使Argus探路者项目达到比以往任何望远镜都快得多的探测速度，这将使新的发现成为可能。例如，超耀斑是恒星发出的非常快的辐射爆发。了解超耀斑的行为对于寻找地球以外的生命至关重要，它需要高速观测，以及在事件发生时迅速将多个望远镜指向它们的能力。其他神秘的快速事件也在其他波长上被观测到，它们有对应的可见光，可以揭示它们是什么。这些和其他“瞬变”发生在天空中随机的时间和地点。捕捉它们的最好方法是尽可能快地勘测天空。《阿古斯探路者》将拍摄一大片天空的电影。它将观察数以千计的瞬变过程，并迅速向其他地面和太空望远镜发出警报。研究人员将为开发和升级莫尔黑德天文馆的主要时间域天文展览做出贡献，以提高每年与展览互动的大约15万学童的参与度和天文灵感。2.3GPix Argus探路者阵列覆盖了一条天空的条纹，赤纬92度，右纬3.7度，1.4英寸/像素的采样几乎达到了大气视界。该系统跟踪天空的每一条条纹15分钟，因此几乎每晚覆盖整个北方天空。Pathfinder的CMOS探测器能够以仅毫秒级的开销读出整个帧，并具有1电子级的读数噪声，这接近于单光子检测能力。探路者的大型高速探测器阵列、宽通带和非常宽的视场相结合，使该系统能够达到数量级，而不是最接近的1秒持续时间搜索。在30秒的节奏基础探测中，探路者将比之前最好的能够覆盖整个天空的探测器深8个数量级，它覆盖的调查区域将至少比更大望远镜上尝试的深度、窄时间尺度的探测器大5000倍。这些能力将使人们能够全面描述高速天空的特征，以及对个别群体的详细天体物理测量，如快速射电爆发和恒星超耀斑。对于后者，探路者将获得时间分辨的光曲线和光谱，以模拟耀斑至关重要的高能粒子释放，并限制它们的宜居性影响。对于最大的耀斑，该系统将使用SWIFT卫星的新的快速旋转能力来获得分钟级的直接EUV和X射线通量测量，从而直接测量潜在的行星宜居影响。该奖项反映了NSF的法定任务，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

New sensor technologies and mass-produced optical systems will allow the Argus Pathfinder project to push to far faster survey speeds than any telescope before, which will enable new discoveries. For example, superflares are very fast bursts of radiation from stars. Understanding superflare behavior is crucial to the search for life beyond Earth, and it requires high-speed observations and the ability to point multiple telescopes very rapidly to events as they occur. Other mysterious fast events have been seen at other wavelengths, and they have visible-light counterparts that can shed light on what they are. These and other “transients” occur at random times and places in the sky. The best way to catch them is to survey as much of the sky as possible, as quickly as possible. Argus Pathfinder will make a “movie” of a very large patch of sky. It will observe thousands of transients as they evolve, and rapidly alert other ground- and space-based telescopes. The investigators will contribute to developing and upgrading the Morehead Planetarium’s major time-domain astronomy exhibit to improve the engagement and astronomical inspiration of the approximately 150,000 schoolchildren who interact with the exhibit each year. The 2.3GPix Argus Pathfinder array covers a stripe of the sky 92 degrees in declination and 3.7 degrees in right ascension, with 1.4”/pixel sampling almost reaching the atmospheric-seeing limit. The system tracks each stripe of the sky for 15 minutes, and thus covers almost the entire Northern sky each night. Pathfinder’s CMOS detectors are capable of reading out entire frames with only millisecond-level overheads and have 1-electron-level readnoise, which comes close to single-photon detection capabilities. Pathfinder’s large high-speed detector array, wide passband, and very wide field of view combine to make the system capable of reaching orders of magnitude beyond the closest comparable searches for 1-second duration transients. In the 30s-cadence base survey, Pathfinder will push eight magnitudes deeper than the best previous probes capable of covering the entire sky, and it will cover a survey area at least 5,000 times larger than the deep, narrow minute-timescale probes attempted on larger telescopes. These capabilities will enable a comprehensive characterization of the high-speed sky – and detailed astrophysical measurements of individual populations such as fast radio bursts and stellar superflares. For the latter, Pathfinder will obtain time-resolved light curves and spectra to model the flares’ all-important energetic particle releases and constrain their habitability impacts. For the largest flares, the system will use the new rapid-slew capabilities of the Swift satellite to obtain minute-timescale direct EUV and X-ray flux measurements, and thus a direct measurement of potential planetary habitability impacts.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.