WoU-MMA: Collaborative Research: A Next-Generation SuperNova Early Warning System for Multimessenger Astronomy

当一颗大质量恒星到达生命的尽头时，恒星的核心会坍塌，产生超新星。虽然在视觉上很壮观，但超新星中只有不到1%的能量以可见光或动能的形式释放到周围环境中。超新星的大部分能量被核心坍缩过程中产生的中微子带走了。与光子相比，中微子与物质的相互作用非常弱。因此，它们可以毫不延迟地从超新星爆炸中流出，从而在光学爆炸可见前几分钟到几小时到达地球。因此，探测到来自超新星的第一批中微子为进一步的观测提供了早期预警。超新星早期预警系统（SNEWS）是一个由世界各地的中微子探测器组成的网络，旨在为我们银河系中的超新星提供自动预警。虽然罕见，但星系超新星将为研究核心坍缩超新星的物理学以及中微子的性质提供一个独特的机会。来自SNEWS的警报将使世界各地的物理学家和天文学家能够观测到超新星的早期阶段。SNEWS项目致力于让业余天文学家参与这门科学，因为他们在超新星的光学观测中发挥着重要作用。该合同支持由几个机构组成的合作小组升级现有的SNEWS实时警报系统，包括新的探测器，并准备更好地利用这些探测器的集体能力。该团队将建立中微子光曲线模型，并使用这些模型来评估所有可用的中微子探测器中的预期信号。他们将利用中微子相互作用的各向异性，以及基于中微子信号的相对观测时间的实验间三角测量算法，开发出快速确定超新星方向的最佳方法。及时的方向信息将大大提高在多个通道中发现早期光曲线的可能性。这不仅对超新星爆炸的理解至关重要，而且对包括天体物理学、核物理学和粒子物理学在内的许多其他物理学领域也至关重要。最后，他们将根据对伴随一颗注定要灭亡的恒星最后燃烧阶段而产生的中微子的增加的观察，开发出超新星爆发前的警报。该提案还支持业余天文团体参与这一令人兴奋的研究领域，创建一个专题天文馆节目，以及用于教育和警报传播的智能手机应用程序。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。

When a massive star reaches the end of its life, the core of the star collapses, producing a supernova. While visually spectacular, less than 1% of the energy in the supernova is released as visible light or as kinetic energy in the surrounding environment. Most of the energy from the supernova is carried away by neutrinos produced during the collapse of the core. In contrast to photons, neutrinos interact only very weakly with matter. They can therefore stream out of the supernova explosion without delay and thus arrive at Earth minutes to hours before the optical explosion may be visible. Detecting the first neutrinos from a supernova therefore provides an early alert to trigger further observations. The SuperNova Early Warning System (SNEWS) is a network of neutrino detectors around the world designed to provide automated early alerts for supernovae in our galaxy. While rare, a galactic supernova would provide a unique opportunity to study the physics of core-collapse supernova, as well as the properties of neutrinos. Alerts from SNEWS will enable observations of the earliest phases of the supernova for physicists and astronomers around the world. The SNEWS project works to engage amateur astronomers by involving them in this science, as they play an important role in optical observations of supernova.This award supports a collaborative group from several institutions to upgrade the existing SNEWS real-time alert system to include new detectors, and to prepare to better exploit the collective capabilities of these detectors. The team will model neutrino light curves and use those models to evaluate the expected signals in all available neutrino detectors. They will develop optimal methods for prompt determination of the supernova direction using both neutrino interaction anisotropies, as well as inter-experiment triangulation algorithms which will be based on relative observed timing of the neutrino signals. Prompt directional information will sharply improve the likelihood to detect the early onset of the light curve in multiple channels. This is crucial not only for the understanding of supernova explosions, but also for many other areas of physics including astrophysics, nuclear physics, and particle physics. Finally they will develop pre-supernova alerts based on the observation of the uptick in neutrino production that accompanies the final burning stages of a doomed star. This proposal also supports involvement of the amateur astronomy community in this exciting area of research, the creation of a topical planetarium show, as well as a smartphone app for use in education and alert dissemination.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.