Collaborative Proposal: Enhanced Gravitational Wave Search via Simultaneous Advanced LIGO/Virgo and Evryscope Detection

最近LIGO/室女座引力波天文台及其对应的电磁(EM)天文台探测到了第一颗双星中子星(BNS)合并的引力波(GW)，开启了一个多信使天体物理的新时代。GW170817事件启发了一种新的GW搜索战略，使用同步全天光学成像测量来提供更高的探测置信度以及源识别/定位。这笔赠款将用于在高级LIGO/处女座(aLIGO/处女座)运行3(03)操作中开发和测试改进的GW搜索，有可能大幅增加确认的GW检测数量。这将通过利用引力波和光学观测站的现有投资，使臭氧期间探测到的系统数量估计增加约25%，从而极大地促进国家利益的科学进步，并为未来的多信使调查铺平道路，这可能会使探测到的源数量翻两番。这项拟议的研究是多信使天体物理学、广义相对论、数字信号处理和计算的交叉学科，这要求年轻的研究人员深入了解现代天体物理理论，了解引力波仪器，并让他们有机会获得复杂的信号/图像处理算法、计算方法、大数据集处理和高性能计算的第一手经验。这里提出的新的GW搜索基于LIGO/Virgo亚阈值触发和使用EvryScope技术的同步光学成像。EvryScope以2分钟的节奏同时拍摄了整个可观察到的夜间天空。然后，科学家可以只选择aLIGO/Virgo误差区域中出现在与GW候选对象相同的2分钟窗口内的光学瞬变事件-将仅GW-Only的虚警概率降低20,000倍以上。任何夜间GW活动。这使得能够提高边缘GW事件的检测置信度，从而增强GW检测量。GW1708187‘S光学对应物可以被当前的射电望远镜探测到D~260MPC，未来的射电望远镜系统可以探测到350MPC以上的距离。分析表明，未来的EvryScope式探测器网络将使探测到的GW事件的数量比仅观测GW事件的数量增加约2-4倍。这样一个未来的网络将特别有利于GW源人口研究和GW事件的宇宙学应用。这种方法还将覆盖光学光曲线的最亮部分，并为所有这些事件提供弧形第二级定位，这将极大地改善整个社区的EM后续响应，从而改善解释GW事件含义的天体物理学背景。这里拟议的工作是在LIGO/Virgo 03中进行亚阈值GW搜索，使用EvryScope北和南设施同时进行光学覆盖。基于GW170817的S GW属性、光学对应项和此处提供的分析，这样的搜索可能会使O3中确认的BNS合并数量额外增加~25%的检测。此裁决反映了美国国家科学基金会的法定使命，并已通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

The recent gravitational wave (GW) detection of the first binary neutron star (BNS) merger by the LIGO/Virgo gravitational wave observatories and its associated electromagnetic (EM) counterparts has ushered in a new era of multi-messenger astrophysics. The GW170817 event has inspired a new GW search strategy using simultaneous all-sky optical imaging measurements to provide improved detection confidence as well as source identification/localization. This grant will fund the development and testing of this improved GW search in Advanced LIGO/Virgo (aLIGO/Virgo) operation run 3 (O3), with the potential to substantially increase the number of confirmed GW detections. This will significantly improve the progress of science in the national interest by leveraging the existing investments in gravitational wave and optical observatories to provide an estimated ~25% enhancement in the number of detected systems during O3, and pave the way for future multi-messenger investigations that could potentially quadruple the number of detected sources. The proposed research is at the intersection of the multi-messenger astrophysics, general relativity, digital signal processing and computing, which require young researchers to develop a deep knowledge of modern astrophysical theories, and understanding of gravitational wave instrumentation, and gives them opportunity to get firsthand experience with sophisticated signal/image-processing algorithms, computational methods, manipulation of large data sets and high performance computing.The novel GW search proposed here is based on combining aLIGO/Virgo sub-threshold triggers with simultaneous optical imaging using the Evryscope technique. Evryscope images the entire observable night-time sky simultaneously with 2-minute cadence. Scientists can then select only those optical transient events in the aLIGO/Virgo error region which appear within the same 2-minute window as the GW candidate - reducing the GW-only false alarm probability by factors larger than 20,000. for any night-time GW events. This enables improved detection confidence for marginal GW events and thus enhanced GW detection volume. GW1708187's optical counterpart could be detected by the current Evryscope out to D ~260 Mpc, and future Evryscope-style systems to distances further than 350 Mpc. Analyses show that a future network of Evryscope-style detectors would enhance the number of GW events detected by a factor of ~2-4 compared to GW-only observations. Such a future network would particularly benefit GW source population studies and cosmological applications of GW events. This approach will also provide coverage of the brightest portion of the optical lightcurve, and arcsecond-level localization for all of these events, which will dramatically improve the EM followup response from the community as a whole, leading to improved astrophysical context for interpreting the implications of the GW event. The proposed work here is to carry out a sub-threshold GW search in aLIGO/Virgo O3, using the Evryscope North and South facilities for simultaneous optical coverage. Based on the properties of GW170817's GW properties, optical counterpart, and analyses presented here, such a search could add an additional ~25% more detections to the number of confirmed BNS mergers in O3.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.