RUI: Multi-Messenger Astronomy with LIGO Gravitational-Wave Bursts

2017年8月观测到的两颗中子星既有引力波又有光的合并，开启了引力多信使天文学时代。虽然仍然可以从两个巨大致密天体的合并中学到很多东西，但重要的是也要倾听引力波交响乐中的其他声音。当一颗古老的大质量恒星坍塌成一颗超高密度中子星时，某些类型的超新星应该会发出引力波和光。对这些超新星的多信使观测可以帮助我们了解这些壮观的爆炸是如何发生的，为什么会发生，以及由此形成的中子星。多信使观测也可能是解开太空中短暂而明亮的射电发射的神秘来源的关键，这种闪光被称为快速射电爆发。该奖项还将包括识别和消除LIGO干涉仪拾取的噪声源的工作，这些噪声源可能会干扰探测到来自太空的真实信号。随着LIGO继续寻找这些新类型的引力波来源，这项工作尤其重要，这些引力波来源没有黑洞或中子开始碰撞时出现的特有的“啁啾”。一年一度的STEM外展工作服务于恩布里-里德尔以北的纳瓦霍民族，也得到了这笔赠款的支持，这是LIGO成员与更广泛的社区分享这一新的、令人兴奋的科学前沿的一种方式。多信使天文学方面的成果，包括与核心坍塌超新星和射电瞬变巧合的搜索，将促进LIGO的科学，同时为学生提供许多参与的机会。核心崩塌的超新星是多信使天文学的一个令人兴奋的目标。从核心坍塌的超新星重建引力波将解决天体物理学中的一些悬而未决的问题，包括爆炸本身的机制，以及关于中微子相互作用和中子星状态方程的基本问题。在接下来的几年里，先进的LIGO的灵敏度的提高，加上更复杂的超新星信号探测和参数估计算法，将极大地增强LIGO对超新星天体物理的贡献，未来的干涉仪具有更大的前景。LIGO开展的另一个多信使天文学领域是寻找与持续时间为毫秒级的射电瞬变的天体物理来源一致的瞬变引力波。由于从中子星小行星地震到宇宙弦尖端的各种情景，这些辐射可能会与引力波同时发射。引力波天文学有可能揭示几种类型的射电发射，可能包括快速射电爆发。由于环境干扰和干涉仪自身行为的共同作用，瞬变地球背景的存在使寻找引力波爆发变得更加困难。了解这些环境干扰并从干涉数据中删除它们对于进行引力波的敏感搜索至关重要，因为这可能意味着在统计上具有重大意义的引力波探测和低于阈值的事件之间的差异。这笔赠款将支持在探测器特性、确定和减轻干涉仪中的非天体物理背景以及应用否决权以消除这些背景方面的大量工作。该奖项还促进了从高中到研究生的各个层面的科学教育和推广。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。

The observation of the merger of two neutron stars in August 2017 with both gravitational waves and light began the era of gravitational multi-messenger astronomy. While much can still be learned from the mergers of two massive compact objects, it is important to also be listening for other sounds in the symphony of gravitational waves. Certain types of supernovae should emit gravitational waves along with light as an old and massive star collapses into an ultra-dense neutron star. Multi-messenger observations of these supernova could help us learn a great deal about how and why these spectacular explosions occur, and about the neutron star that forms as a result. Multi-messenger observations could also be a key to unlocking the mysterious origin of short, bright flashes of radio emission from space called fast radio bursts. This award will also cover work in identifying and getting rid of sources of noise picked up by the LIGO interferometers that can interfere with detecting real signals from space. This work is particularly important as LIGO continues to look for these new types of gravitational wave sources which don't have the characteristic "chirp" that occurs when black holes or neutron starts collide. Annual STEM outreach work serving the Navajo nation north of Embry-Riddle, also supported by this grant, is one way in which LIGO members can share this new and exciting frontier in science with the broader community.Efforts in multi-messenger astronomy, including searches in coincidence with core-collapse supernovae and radio transients, will enhance LIGO science while providing many opportunities for student involvement. Core-collapse supernovae are an exciting target for multi-messenger astronomy. The reconstruction of a gravitational wave from a core-collapse supernova would address a number of open questions in astrophysics, including the mechanism of the explosion itself as well as fundamental questions about neutrino interactions and the neutron star equation of state. In the next few years, the improved sensitivity of Advanced LIGO combined with more sophisticated algorithms for detection and parameter estimation of supernova signals will greatly enhance LIGO's contributions to supernova astrophysics, and future interferometers carry even more promise. Another area of multi-messenger astronomy which LIGO has undertaken is the search for transient gravitational waves in coincidence with astrophysical sources of radio transients of duration on the scale of milliseconds. These could be emitted simultaneously with gravitational waves due to scenarios ranging from neutron star asteroseismology to cosmic string cusps. Gravitational wave astronomy has the potential to shed light on several types of radio emission, possibly including fast radio bursts. The search for gravitational wave bursts is made more difficult by the presence of transient terrestrial background, resulting from a combination of environmental disturbances and behavior of the interferometers themselves. Understanding these environmental disturbances and removing them from interferometric data is critical in conducting sensitive searches for gravitational waves, as it can mean the difference between a statistically significant gravitational wave detection and a sub-threshold event. This grant will support substantial effort in detector characterization, the identification and mitigation of non-astrophysical background in the interferometers and application of vetoes to eliminate them. This award also facilitates science education and outreach at every level from high school to graduate student.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.