Compelling Evidence for a Harmonic in the Light Curve of the Supermassive Black Hole Binary Candidate PKS J1309+1154
California Institute of Technology（加州理工学院）；University of Michigan（密歇根大学）；Stanford University（斯坦福大学）；University of Warsaw（华沙大学）；Purdue University（普渡大学）；University of Crete（克里特大学）；Foundation for Research and Technology-Hellas（希腊研究与技术基金会）；University of Colorado（科罗拉多大学）；National Institute of Standards and Technology（国家标准与技术研究院）；University of Turku（图尔库大学）；Aalto University（阿尔托大学）
A. C. S. Readhead, M. F. Aller, A. G. Sullivan, R. D. Blandford, P. Mróz, P. V. De la Parra, B. Molina, E. R. Most, M. L. Lister, A. Synani, H. Aller, M. C. Beg… 展开作者
A. C. S. Readhead, M. F. Aller, A. G. Sullivan, R. D. Blandford, P. Mróz, P. V. De la Parra, B. Molina, E. R. Most, M. L. Lister, A. Synani, H. Aller, M. C. Begelman, Y. Ding, M. J. Graham, F. Harrison, T. Hovatta, I. Liodakis, W. Max-Moerbeck, V. Pavlidou, T. J. Pearson, V. Ravi, R. A. Reeves, T. Surti, K. Tassis, S. E. Tremblay, J. A. Zensus
We recently discovered a supermassive black hole binary (SMBHB) candidate, PKS J1309+1154, in the combined 46-yr University of Michigan Radio Astronomy Observatory (UMRAO) plus Owens Valley Radio Observatory (OVRO) blazar monitoring programs at 14.5/15 GHz. The light curve of PKS 1309+1154 exhibits a 17.9 year periodicity. We also reported a hint of a first harmonic with a 9 year periodicity in this object. Further analysis of the PKS J1309+1154 light curve provides compelling evidence that both the fundamental and the harmonic are real, confirming the existence of real periodicities in blazar light curves. This is the first case, to our knowledge, of watertight evidence for a fundamental and a harmonic periodicity in a blazar light curve. It makes PKS J1309+1154 a \textit{strong\/} supermassive black hole binary (SMBHB) candidate, and thus the third such candidate to be revealed through long-term radio monitoring, the other two being PKS J0805--0111 and PKS 2131--021, both discovered through the OVRO 40 m Telescope monitoring program. It is argued that hundreds of SMBHB candidates will be discovered by the Vera Rubin and Simons Observatories. Coherent searches for gravitational waves from a network of SMBHB candidates, starting immediately, are strongly motivated.
Atacama Cosmology Telescope: Observations of supermassive black hole binary candidates. Strong sinusoidal variations at 95, 147 and 225 GHz in PKS 2131$-$021 and PKS J0805$-$0111
David A. Dunlap Department of Astronomy & Astrophysics, University of Toronto（多伦多大学）；Specola Vaticana (Vatican Observatory)（梵蒂冈天文台）；Kavli Institute for Astronomy & Astrophysics, Peking University（北京大学）；Department of Astronomy, School of Physics, Peking University（北京大学物理学院天文学系）；Astronomical Observatory, University of Warsaw（华沙大学）；Institute of Theoretical Astrophysics, University of Oslo（奥斯陆大学）；Institute of Astrophysics, Foundation for Research & Technology-Hellas（希腊研究与技术基金会）；Kavli Institute for Particle Astrophysics and Cosmology, Department of Physics, Stanford University（斯坦福大学）；Canadian Institute for Theoretical Astrophysics, University of Toronto（多伦多大学）；Department of Physics & Astronomy, University of Pennsylvania（宾夕法尼亚大学）；Joseph Henry Laboratories of Physics, Jadwin Hall, Princeton University（普林斯顿大学）；Department of Astrophysical Sciences, Peyton Hall, Pr（普林斯顿大学）
PKS 2131-021 -- Discovery of Strong Coherent Sinusoidal Variations from Radio to Optical Frequencies: Compelling Evidence for a Blazar Supermassive Black Hole Binary
Constraining Orbital Eccentricity of a Supermassive Black Hole Binary Candidate PKS 2131-0211
Joint Astronomy Programme, Department of Physics, Indian Institute of Science（印度科学研究所物理系联合天文学项目）；Department of Astronomy and Astrophysics, Tata Institute of Fundamental Research（塔塔基础研究院天文与天体物理学系）；Max-Planck-Institut für Radioastronomie（马克斯·普朗克射电天文研究所）；Department of Physical Sciences, Indian Institute of Science Education and Research Kolkata（加尔各答印度科学教育研究所物理科学系）
Relativistic Jets and Winds in Radio-Identified Supermassive Black Hole Binary Candidates
Stanford University（斯坦福大学）；University of Crete（克里特大学）；Foundation for Research and Technology-Hellas（希腊研究与技术基金会）；University of Colorado（科罗拉多大学）；California Institute of Technology（加州理工学院）
A Search for Supermassive Black Hole Binary Candidates in 46-Year Radio Light Curves of 83 Blazars
University of Warsaw（华沙大学）；California Institute of Technology（加州理工学院）；Foundation for Research and Technology-Hellas（希腊研究与技术基金会）；University of Michigan（密歇根大学）；NASA Ames Research Center（美国国家航空航天局艾姆斯研究中心）；University of Colorado（科罗拉多大学）；National Institute of Standards and Technology（美国国家标准与技术研究院）；Stanford University（斯坦福大学）；University of Turku（图尔库大学）；Aalto University（阿尔托大学）；Purdue University（普渡大学）；University of Crete（克里特大学）
Upper limits on microhertz gravitational waves from supermassive black-hole binaries using PSR J1909-3744 data from the second IPTA data release
Xinjiang Astronomical Observatories, Chinese Academy of Sciences（中国科学院新疆天文台）；University of Chinese Academy of Sciences（中国科学院大学）；Institute of Optoelectronic Technology, Lishui University（丽水学院光电技术研究所）
A Dark-matter Origin of Little Red Dots: Early Seeding and Super-Bondi Accretion
Peking University（北京大学）；Kavli Institute for Astronomy and Astrophysics, Peking University（北京大学科维理天文与天体物理研究所）；Beijing Normal University（北京师范大学）；School of Physics and Astronomy, Beijing Normal University（北京师范大学物理学院）；University of Chinese Academy of Sciences（中国科学院大学）；School of Astronomy and Space Science, University of Chinese Academy of Sciences（中国科学院大学天文与空间科学学院）
