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

该项目将全面研究正在积极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的黑洞，它们的活动星系核(AGN)释放出巨大的能量，可以超过银河系中所有恒星的能量。AgN辐射随时间变化，这种变化是随机的或随机的，这编码了重要的AGN吸积物理。该团队将分析两项调查的数据集：全天超新星自动调查(ASAS-SN)和凌日系外行星调查卫星(TESS)。合并后的数据集将使该团队能够研究几分钟到十年时间尺度的光学波段中活动星系核的可变性，频率跨度为五个数量级。这个项目的AGN样本接近10,000个，比之前的研究大得多。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异性特征。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项目。这些活动每年将影响1200名K-12学生，让拟议教育计划的参与者参与高质量的学习体验，以加强他们的STEM内容知识，并激励下一代学生追求并在STEM职业生涯中脱颖而出。AAS-SN是一个分布在全球各地的小型望远镜网络，每天对亮度超过18等的天体进行全天候监测。ASS-SN已经积累了10年的监测数据，这使得能够在光学波段对明亮的AGN进行大样本的AGN变异性研究。这些明亮的活动星系核也将由TESS在太空中以10-30分钟的节奏进行短时间尺度的监测。结合ASAS-SN和TESS数据将允许在频率空间中以五个数量级研究AGN光学变异性，探测分钟到十年的时间尺度。AAS-SN、TESS、SWIFT和RXTE测量的组合为联合研究明亮活动星系核的光学和X射线变化提供了独特的数据集。该项目由MPS/天文科学部(AST)和既定的激励竞争性研究计划(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。

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.