CAREER: Multimessenger Astrophysics with Pulsar Timing Arrays in the Detection Era

职业：探测时代脉冲星计时阵列的多信使天体物理学

• 批准号: 2339728
• 负责人: Jeffrey Hazboun
• 金额: $ 40万
• 依托单位: Oregon State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-01-01 至 2028-12-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2339728&HistoricalAwards=false
• 关键词: CAREER; Multimessenger; Astrophysics; Pulsar; Timing

The recent announcement by the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) and pulsar timing array (PTA) collaborations around the world of evidence for a gravitational wave background (GWB) demonstrates that PTAs are moving into an unprecedented sensitivity regime for gravitational wave (GW) signals in the nanohertz frequency range. PTAs can see further back in time than the cosmic microwave background radiation and allow us to survey the population of supermassive binary black holes (SMBBHs) as a stochastic GWB. Detection of the background heralds the coming of individual source detections just when the Vera C. Rubin Observatory and the ten-year Legacy Survey of Space and Time (LSST) are scheduled to begin obtaining consistent and high quality time series data of active galactic nuclei (AGN) --- perfectly timed to coincide with the era of the first single-source detections in the PTA band. GW detections at these frequencies take time and necessitate the use of state-of-the-art data analysis techniques to build custom noise models for individual pulsar data sets in order to enhance the huge investment of the NSF into nanohertz gravitational wave astronomy just as PTAs enter the detection era. As the cosmic symphony of the stochastic GWB becomes more significant in the data, it is now necessary for PTAs to tune these galactic-scale detectors to optimize the ability to also resolve individual SMBBHs. PTAs will arbitrate the SMBBH hypothesis for quasiperiodic light curves in AGN, and this work will maximize the multimessenger detectability space of SMBBH systems by informing PTA and LSST observing strategies in order to ensure the detection of a multimessenger source during the LSST-era. The project includes curriculum development and implementation of a summer workshop in astrophysics-themed data analysis that will foster inspired teaching, stimulate excitement in PTA research, facilitate the learning goals of undergraduate and graduate students, and support the transition of community college students into 4-year schools. The first research goal will be using techniques recently pioneered to transform PTA noise mitigation strategies with the use of custom Bayesian models to gain from the data we already have in hand. Preliminary analyses have shown significant changes in parameter recovery and significance statistics when using these custom models. This work will inform a reconceptualization of the use of detector characterization tools to rethink pulsar observing strategies and the reorganization of these tools for lightweight predictions of single-source detectability of GW candidates from electromagnetic time-domain surveys. Supported by these first two goals will be research to develop the framework and software interface needed to quickly assess AGN for the presence of SMBBHs.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.

最近，北美纳赫兹引力波天文台（NANOGrav）和脉冲星定时阵列（PTA）在世界各地合作宣布了引力波背景（GWB）的证据，表明PTA正在进入纳赫兹频率范围内引力波（GW）信号的前所未有的灵敏度范围。PTA可以看到更远的时间比宇宙微波背景辐射，并允许我们调查人口的超大质量双黑洞（SMBBH）作为一个随机的GWB。背景检测预示着个体源检测的到来。鲁宾天文台和为期十年的时空遗产调查（LSST）计划开始获得活动星系核（AGN）的一致和高质量的时间序列数据---完美的时间安排与PTA波段首次单源探测的时代相吻合。在这些频率下的GW探测需要时间，并且需要使用最先进的数据分析技术来为单个脉冲星数据集构建自定义噪声模型，以便在PTA进入探测时代时，提高NSF对纳赫兹引力波天文学的巨额投资。随着随机GWB的宇宙交响乐在数据中变得更加重要，现在有必要让PTA调整这些银河尺度的探测器，以优化分辨单个SMBBH的能力。PTA将仲裁SMBBH假设AGN中的准周期光变曲线，这项工作将最大限度地提高SMBBH系统的多信使探测空间，通过通知PTA和LSST观测策略，以确保在LSST时代检测到多信使源。该项目包括课程开发和实施以天体物理学为主题的数据分析夏季研讨会，这将促进启发式教学，激发PTA研究的兴奋，促进本科生和研究生的学习目标，并支持社区大学生过渡到4年制学校。第一个研究目标将是使用最近开创的技术，通过使用自定义贝叶斯模型来转换PTA噪声缓解策略，以从我们已经掌握的数据中获益。初步分析表明，使用这些自定义模型时，参数恢复和显著性统计量发生了显着变化。这项工作将告知使用探测器表征工具的重新概念化，以重新思考脉冲星观测策略，并重新组织这些工具，用于从电磁时域调查中对GW候选者的单源可探测性进行轻量级预测。在前两个目标的支持下，将研究开发快速评估活动星系核是否存在SMBBH所需的框架和软件接口。该奖项反映了NSF的法定使命，并被认为值得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来支持。