RUI: LIGO Calibration, Gravitational-Wave Searches, and Parameter Estimation in the Advanced Detector Era

RUI：先进探测器时代的 LIGO 校准、引力波搜索和参数估计

• 批准号: 1607178
• 负责人: Madeline Wade
• 金额: $ 15万
• 依托单位: Kenyon College
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-07-15 至 2020-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1607178&HistoricalAwards=false
• 关键词: RUI; LIGO; Calibration; Gravitational; Wave

The first direct detection of gravitational waves by Advanced LIGO in September 2015 has officially launched the era of gravitational-wave astronomy, bringing a plethora of new astrophysics to our doorstep. This grant supports the work of members of the LIGO Scientific Collaboration at Kenyon College. Kenyon LIGO group members have lead roles in the calibration of the Advanced LIGO (aLIGO) interferometers and the search for gravitational wave signals from large black holes. The calibration of the aLIGO detectors is the first fundamental step after data has been collected by the detector. Only after the data is calibrated can searches for gravitational wave signals begin. LIGO scientists search for a range of sources, but the most promising source is the coalescence of two compact, astrophysical objects, such as black holes and neutron stars. Historically, LIGO has performed careful searches for black hole systems with masses that range up to 100 times the mass of the Sun. Members of the Kenyon LIGO group are part of the effort to expand this search to black holes of even higher masses. These large black holes may hold key answers as to how the supermassive black holes at the centers of galaxies were formed. Additionally, the Kenyon LIGO group is exploring and improving aLIGO's ability to extract information about the matter that composes neutron stars in preparation for the first gravitational wave detection from a coalescing neutron star system. While electromagnetic signals from binary neutron star systems can provide insight into the surface of neutron stars, the detection of gravitational waves from a binary neutron star system could dig deeper and reveal secrets of the illusive neutron star matter itself. Finally, this project also supports the expansion of an existing NSF-funded outreach program at Kenyon College that targets engaging middle-school-aged audiences with exciting, hands-on science workshops. Separate workshops are held for middle school boys (LADS: Learning and Doing Science) and middle school girls (GSS: Girls Science Saturdays) several Saturdays throughout the school year. This award supports three main efforts in the field of gravitational-wave physics. The first is related to ongoing work in the calibration of the aLIGO detectors. Specifically, Kenyon LIGO group members will not only maintain existing low-latency calibration software, which is a large task as the calibration procedure is constantly changing with upgrades to the interferometers, but they will also work towards reducing the latency of the current calibration software from around a few tens of seconds down to a few seconds. The lowest possible latency calibration is crucial for electromagnetic follow-up of gravitational wave signal candidates. The main methods that will be employed to reduce the latency of the calibration software are to reduce the complexity of the procedure, shift as much of the calibration procedure as possible into the real-time instrument computers, and improve the computational efficiency of all existing calibration software. The award also supports the development and execution of a modeled, matched-filter search for intermediate mass black hole binary (IMBHB) systems. The goal of the search is to make the first confident detection of black holes in the intermediate mass range or to provide upper limits on the existence of IMBHB systems. Existing search software is being optimized to fit the needs of a higher mass, and therefore shorter waveform, matched filter search, and the search is being developed to run in a low-latency mode during future observing runs. Finally, this grant supports the development of tools to extract information about the neutron star equation of state from a binary neutron star gravitational wave detection. Markov Chain Monte Carlo (MCMC) gravitational wave parameter estimation software is being modified to more optimally explore the neutron star equation of state parameter space, and software to allow for the use of different models of the neutron star equation of state is being developed. The first few gravitational wave detections from binary neutron star systems will be able to provide a wealth of new knowledge about neutron star matter.

2015年9月，Advanced Ligo对引力浪的首次直接发现是正式推出了引力波天文学时代，这使我们家门口有很多新的天体物理学。 该赠款支持肯尼恩学院的Ligo科学合作成员的工作。 Kenyon Ligo Group成员在高级Ligo（Aligo）干涉仪的校准中具有铅角色，并从大型黑洞中搜索引力波信号。 Aligo探测器的校准是检测器收集数据后的第一步。 只有在校准数据后，才可以开始搜索引力波信号。 Ligo科学家正在寻找一系列来源，但最有希望的来源是两个紧凑的天体物理物体（例如黑洞和中子星）的合并。 从历史上看，Ligo仔细搜索了黑洞系统，其质量的范围是太阳质量的100倍。 Kenyon Ligo集团的成员是将这种搜索扩展到更高群体的黑洞的努力的一部分。 对于如何形成星系中心的超大质量黑洞，这些大孔可​​能会有关键的答案。 此外，Kenyon Ligo组正在探索和提高Aligo提取有关构成中子星的信息的能力，以准备从共融合的中子恒星系统中进行首次重力波检测。 虽然来自二进制中子星系的电磁信号可以提供对中子星体表面的洞察力，但从二元中子恒星系统中检测引力波可以更深入地挖掘并揭示幻象的中子恒星物质本身的秘密。 最后，该项目还支持Kenyon College现有的NSF资助的外展计划的扩展，该计划的目标是通过激动人心的动手科学讲习班吸引中学观众。 在整个学年几个星期六，为中学男孩（LAD：学习与做科学）和中学女生（GSS：女子科学星期六）举行了单独的研讨会。该奖项支持引力波物理学领域的三项主要努力。 第一个与阿里戈探测器校准的持续工作有关。 具体而言，Kenyon Ligo Group成员不仅将维护现有的低延迟校准软件，这是一项艰巨的任务，因为校准过程随着升级到干涉仪的升级而不断变化，而且还将致力于将当前校准软件的延迟从大约几秒钟减少到几秒钟。 最低可能的潜伏期校准对于重力波信号候选物的电磁随访至关重要。 减少校准软件潜伏期的主要方法是降低过程的复杂性，将尽可能多的校准过程转移到实时仪器计算机中，并提高所有现有校准软件的计算效率。 该奖项还支持对中间质量黑洞二进制（IMBHB）系统的建模，匹配过滤器搜索的开发和执行。 搜索的目的是首先在中间质量范围内对黑洞进行首次自信检测，或者为IMBHB系统的存在提供上限。 现有的搜索软件正在优化以满足较高质量的需求，因此较短的波形，匹配的过滤器搜索，并且正在开发搜索以在未来的观察过程中以低延迟模式运行。 最后，该赠款支持开发工具，以从二进制中子恒星重力波检测中提取有关状态的中子星方程的信息。 Markov Chain Monte Carlo（MCMC）重力波参数估计软件正在修改，以更优化地探索状态参数空间的中子星方程，并允许开发使用状态的中子星方程的不同模型的软件。二进制中子星系的前几个重力波检测将能够提供有关中子星形物质的大量新知识。