A Comprehensive Study of AGN Optical Variability from Minute to Decade Time Scales

从分钟到十年时间尺度的活动星系核光学变率的综合研究

• 批准号: 2307802
• 负责人: Xinyu Dai
• 金额: $ 35.64万
• 依托单位: University of Oklahoma Norman Campus
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-01 至 2026-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2307802&HistoricalAwards=false
• 关键词: Comprehensive; Study; AGN; Optical; Variability

This project will comprehensively investigate the variation of radiation emitted from supermassive black holes that are actively accreting matter. Almost all galaxies harbor a supermassive black hole at their centers, and their active galactic nuclei (AGN) emit an enormous amount of energy, which can surpass that of all the stars in the galaxy. AGN radiation is varying over time, and this variability is random or stochastic, which encodes important AGN accretion physics. The team will analyze the dataset from two surveys: the All-Sky Automated Survey for Supernovae (ASAS-SN) and the Transiting Exoplanet Survey Satellite (TESS). The combined datasets will allow the team to study AGN variability in the optical band from minutes to decade time scales, spanning five orders of magnitude in frequency. The AGN sample of this project is approaching 10,000, significantly larger than previous studies. Combining with other surveys in the X-ray band, the team will measure the correlated variability characteristics of AGN between optical and X-ray bands. The team will also train a graduate student and several undergraduate students. In addition, the team will further enrich a portable planetarium program for K-12 schools in central Oklahoma. These activities will impact 1,200 K-12 students annually, engage participants of the proposed educational programs in quality learning experiences that strengthen their STEM content knowledge, and inspire the next generation of students to pursue and excel in STEM careers. ASAS-SN is a network of small telescopes distributed around the globe to provide daily, all-sky monitoring of celestial objects brighter than 18th magnitude. ASAS-SN has accumulated 10 years of monitoring data, and this enables AGN variability studies in the optical band for a large sample of bright AGN. These bright AGN will also be monitored from space by TESS in short time-scales with 10–30 minute cadences. The combined ASAS-SN and TESS data will allow AGN optical variability study in five orders of magnitude in the frequency space, probing minute to decade timescales. The combination of ASAS-SN, TESS, Swift, and RXTE surveys provide a unique data set to jointly study optical and X-ray variability of bright AGN. This project is jointly funded by MPS/Division of Astronomical Sciences (AST) and the Established Program to Stimulate Competitive Research (EPSCoR).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.

该项目将全面调查从活跃地吸积物质的超大质量黑洞发出的辐射的变化。几乎所有星系的中心都有一个超大质量黑洞，它们的活动星系核（AGN）发出巨大的能量，可以超过星系中所有恒星的能量。活动星系核的辐射是随时间变化的，这种变化是随机的或随机的，这编码了重要的活动星系核吸积物理。该团队将分析来自两个调查的数据集：超新星全天自动调查（ASAS-SN）和凌日系外行星调查卫星（TESS）。合并后的数据集将使研究小组能够研究活动星系核在光学波段的变化，从几分钟到十年的时间尺度，跨越五个数量级的频率。该项目的活动星系核样本接近10，000个，明显大于以前的研究。结合X射线波段的其他调查，该团队将测量活动星系核在光学和X射线波段之间的相关变化特征。该团队还将培训一名研究生和几名本科生。此外，该团队还将进一步丰富俄克拉荷马州中部K-12学校的便携式天文馆计划。这些活动每年将影响1，200名K-12学生，让拟议教育计划的参与者参与优质的学习体验，以加强他们的STEM内容知识，并激励下一代学生追求并在STEM职业中脱颖而出。ASAS-SN是一个由分布在地球仪各地的小型望远镜组成的网络，对亮度超过18等的天体进行全天的日常监测。ASAS-SN已经积累了10年的监测数据，这使得在光学波段研究活动星系核的变化性成为可能。这些明亮的活动星系核也将由TESS在10-30分钟的短时间尺度内从太空进行监测。结合ASAS-SN和TESS数据将允许AGN光学可变性研究在五个数量级的频率空间，探测分钟到十年的时间尺度。ASAS-SN，TESS，Swift和RXTE调查的组合提供了一个独特的数据集，以联合研究明亮AGN的光学和X射线变化。该项目由MPS/天文科学部（AST）和刺激竞争性研究的既定计划（EPSCoR）共同资助。该奖项反映了NSF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。