Collaborative Research: WoU-MMA: New Advancements to Enable Multi-Messenger Neutrino Astrophysics with the Radio Neutrino Observatory in Greenland

该奖项支持相对论和相对论天体物理学的研究，并阐述了美国国家科学基金会“宇宙之窗”宏伟构想的优先领域。对高能天体物理中微子的观测进一步加深了我们对宇宙中最强大的宇宙线加速器和爆炸事件的理解。将天体物理中微子观测与光子、宇宙射线和引力波等其他信使的观测相结合，使我们能够通过多个透镜观察宇宙中最剧烈的过程，并对驱动这些过程的物理学有新的见解。冰立方的中微子观测表明，中微子天空是复杂和动态的，揭示了中微子的未分辨但稳定的背景，以及与blazar有关的中微子耀斑。根据该奖项开展的工作将在射电中微子望远镜和其他多信使天文台之间建立第一个连接，扩大我们对宇宙的多信使视野，将最高能量的中微子包括在内。此外，这项工作将使从冰川学到生物学的广泛跨学科科学成为可能，并使来自世界各地的各种背景的人参与多信使天体物理。格陵兰的射电中微子观测站目前正在建设中，在前几代射电探测器的综合成功和专业知识的基础上，对其进行了优化，以搜索极地冰中的中微子相互作用产生的射电闪光。其领先的灵敏度、巨大的占地面积和精确的指向将提供前所未有的高能中微子流量测量。RNO-G也是第一个可以看到北方天空的超高能中微子天文台。因此，它具有对最高能量中微子源的多信使观测的独特能力，包括由冰立方进行的低能中微子观测引发的中微子源观测。根据该合同开展的工作将对正在建造的RNO-G项目进行必要的升级，以实现其作为完全融入全球多信使观测站网络的最先进仪器的潜力。这一拟议的计划将提高RNO-G的灵敏度和角度分辨率，并使其能够对重要目标做出快速反应，这是多信使战役的必要进步。这项工作将为在第一批高能中微子候选被确定后不久为更广泛的多信使社区提供高质量的事件重建奠定基础。根据该奖项，建议团队将(1)通过改进天线设计和多个站点的重合观测来提高中微子指向分辨率，(2)开发实时事件处理能力，允许更快地周转候选对象并提高触发率，以提高灵敏度，以及(3)使RNO-G能够对来自领先天文台的传入多信使警报做出反应，暂时提高警报方向的灵敏度。该团队将利用这些进展利用RNO-G首次搜索多信使点源和瞬变源。该奖项反映了NSF的法定使命，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。

This award supports research in relativity and relativistic astrophysics and it addresses the priority areas of NSF's "Windows on the Universe" Big Idea. Observations of high energy astrophysical neutrinos further our understanding of the most powerful cosmic ray accelerators and explosive events in the universe. Combining astrophysical neutrino observations with observations from other messengers like photons, cosmic rays, and gravitational waves allows us to view the most violent processes in the universe through multiple lenses and make new insights into the physics that drives them. Neutrino observations with IceCube have shown that the neutrino sky is complex and dynamic, revealing both an unresolved, but steady, background of neutrinos and flares of neutrinos associated with a blazar. The work performed under this award will establish the first connection between a radio neutrino telescope and other multi-messenger observatories, expanding our multi-messenger view of the universe to include the highest-energy neutrinos. In addition, this work will enable a broad range of interdisciplinary science, from glaciology to biology, and engage people from a broad range of backgrounds from around the world in multi-messenger astrophysics.The Radio Neutrino Observatory in Greenland is currently under construction at Summit Station and is optimized to search for the radio flash generated by neutrino interactions in polar ice, building on the combined successes and expertise of earlier generations of radio detectors. Its leading sensitivity, large footprint, and precision pointing will deliver unprecedented measurements of the high-energy neutrino flux. RNO-G is also the first ultra-high energy neutrino observatory with a view of the Northern sky. As such it has unique capabilities for multi-messenger observations of the highest energy neutrinos sources, including those initiated by lower-energy neutrino observations made with IceCube. The work performed under this award will provide the necessary upgrades to the RNO-G project, as it is being built, to realize its potential as a state-of-the-art instrument fully integrated into the world-wide network of multi-messenger observatories. This proposed program will improve RNO-G's sensitivity and angular resolution and enable it to respond rapidly to important targets, necessary advancements for multi-messenger campaigns. This work will lay the groundwork to provide the broader multi-messenger community high-quality event reconstructions shortly after the first high-energy neutrino candidates are identified. Under this award, the proposal team will (1) enhance neutrino pointing resolution through improved antenna designs and coincident observations in multiple stations, (2) develop real-time event processing capabilities, allowing for quicker turnaround on candidates and increased trigger rates to improve sensitivity, and (3) enable RNO-G to respond to incoming multi-messenger alerts from leading observatories, temporarily boosting sensitivity in the alert direction. The team will use these advances to conduct the first searches for multi-messenger point sources and transient sources with RNO-G.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.