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We map the co-eval growth of galaxies and their central supermassive black holes in detail by measuring the incidence of Active Galactic Nuclei (AGN) in galaxies as a function of star formation rate (SFR) and redshift (to z~4). We combine…

Astrophysics of Galaxies · Physics 2019-02-20 James Aird , Alison L. Coil , Antonis Georgakakis

Accretion disk winds are commonly observed in active galactic nuclei (AGN). The winds may be associated with the changing spectral properties of such sources, yet such connections have not been studied in detail so far. This paper presents…

Astrophysics of Galaxies · Physics 2025-04-29 Hagai Netzer

The merger of supermassive black holes (SMBHs) produces mHz gravitational waves (GW), which are potentially detectable by future Laser Interferometer Space Antenna (LISA). Such binary systems are usually embedded in an accretion disk…

High Energy Astrophysical Phenomena · Physics 2024-07-17 Fatemeh Hossein Nouri , Agnieszka Janiuk

We present a numerical framework for the variability of active galactic nuclei (AGN), which links the variability of AGN over a broad range of timescales and luminosities to the observed properties of the AGN population as a whole, and…

Astrophysics of Galaxies · Physics 2019-10-09 Lia F. Sartori , Benny Trakhtenbrot , Kevin Schawinski , Neven Caplar , Ezequiel Treister , Ce Zhang

Recent models of super-massive black hole (SMBH) and host galaxy joint evolution predict the presence of a key phase where accretion, traced by obscured Active Galactic Nuclei (AGN) emission, is coupled with powerful star formation. Then…

Astrophysics of Galaxies · Physics 2015-06-18 Cristian Vignali

This paper estimates the specific accretion-rate distribution of AGN using a sample of 4821 X-ray sources from both deep and shallow surveys. The specific accretion-rate distribution is defined as the probability of a galaxy with a given…

High Energy Astrophysical Phenomena · Physics 2017-08-23 A. Georgakakis , J. Aird , A. Schulze , T. Dwelly , M. Salvato , K. Nandra , A. Merloni , Donald P. Schneider

We examine the continuum variability of active galactic nuclei (AGNs) by analyzing the multi-epoch spectroscopic data from the Sloan Digital Sky Survey. To achieve this, we utilized approximately 2 million spectroscopy pairwise combinations…

Astrophysics of Galaxies · Physics 2025-11-13 Minjin Kim , Suyeon Son , Luis C. Ho

It is still a matter of intense debate how supermassive black holes (SMBH) grow, and the role played by feedback from active galactic nuclei (AGN) in the co-evolution of SMBHs and galaxies. To test the coevolution proposed by theoretical…

Astrophysics of Galaxies · Physics 2022-11-30 George Mountrichas , Francesco Shankar

The sampling strategy of the Transiting Exoplanet Survey Satellite (TESS) make TESS light curves extremely valuable to investigate high cadence optical variability of AGN. However, because the TESS instrument was primarily designed for…

Instrumentation and Methods for Astrophysics · Physics 2023-10-16 Krista Lynne Smith , Lia Sartori

Understanding the dynamical response of quantum materials is central to revealing their microscopic properties, yet access to long-time and large-scale dynamics remains severely limited by rapidly growing computational costs and…

Strongly Correlated Electrons · Physics 2025-12-16 Hubert Pugzlys , Shreyas Varude , Sam Dillon , Huy Tran , Ta Tang , Zhe Jiang , Xuzhe Ying , Chunjing Jia

We analyze the wavelength-dependent variability of a sample of spectroscopically confirmed active galactic nuclei (AGN) selected from near-UV ($NUV$) variable sources in the GALEX Time Domain Survey that have a large amplitude of optical…

High Energy Astrophysical Phenomena · Physics 2016-12-28 T. Hung , S. Gezari , D. O. Jones , R. P. Kirshner , R. Chornock , E. Berger , A. Rest , M. Huber , G. Narayan , D. Scolnic , C. Waters , R. Wainscoat , D. C. Martin , K. Forster , J. D. Neill

The 4 Ms Chandra Deep Field-South (CDF-S) and other deep X-ray surveys have been highly effective at selecting active galactic nuclei (AGN). However, cosmologically distant low-luminosity AGN (LLAGN) have remained a challenge to identify…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 M. Young , W. N. Brandt , Y. Q. Xue , M. Paolillo , D. M. Alexander , F. E. Bauer , B. D. Lehmer , B. Luo , O. Shemmer , D. P. Schneider , C. Vignali

Apart from regular, low-level stochastic variability, some AGN occasionally show exceptionally large changes in the luminosity, spectral shape, and/or X-ray absorption. The most notable are the changes of the spectral type when the source…

High Energy Astrophysical Phenomena · Physics 2022-02-16 Marzena Sniegowska , Mikolaj Grzedzielski , Bozena Czerny , Agnieszka Janiuk

We compile a sample of 92 active galactic nuclei (AGNs) at z<0.75 with $gri$ photometric light curves from the archival data of the Zwicky Transient Facility and measure the accretion disk sizes via continuum reverberation mapping. We…

Astrophysics of Galaxies · Physics 2022-04-20 Wei-Jian Guo , Yan-Rong Li , Zhi-Xiang Zhang , Luis C. Ho , Jian-Min Wang

We adopt a Bayesian X-ray spectral approach to investigate the accretion properties of unobscured ($20<\log(N_{\rm H}/{\rm cm}^{-2}<22$) and obscured ($22< \log(N_{\rm H}/{\rm cm}^{-2}<24$) active galactic nuclei (AGN) to shed light on the…

According to the standard paradigm, the strong and compact luminosity of active galactic nuclei (AGN) is due to multi-temperature black body emission originating from an accretion disk formed around a supermassive black hole. This central…

Astrophysics of Galaxies · Physics 2016-10-18 P. Andrea Rojas Lobos , Rene W. Goosmann , Frederic Marin

A common feature of Active Galactic Nuclei (AGN) is their random variations in brightness across the whole emission spectrum, from radio to $\gamma$-rays. Studying the nature and origin of these fluctuations is critical to characterising…

Astrophysics of Galaxies · Physics 2025-10-17 Mehdy Lefkir , Simon Vaughan , Daniela Huppenkothen , Phil Uttley , Vysakh Anilkumar

X-ray observations of active galactic nuclei (AGN) show variability on timescales ranging from a few hours up to a few days. Some of this variability may be associated with occultation events by clouds in the broad line region. In this…

High Energy Astrophysical Phenomena · Physics 2018-08-08 E. S. Kammoun , F. Marin , M. Dovciak , E. Nardini , G. Risaliti , M. Sanfrutos

Active galactic nuclei (AGNs) exhibit stochastic optical variability, commonly characterized by a damped random walk. The damping timescale is of particular interest because it is related to fundamental properties of the central black hole,…

Astrophysics of Galaxies · Physics 2025-09-29 Ruisong Xia , Zhen-Yi Cai , Yongquan Xue , Xian-Liang Lu , Guowei Ren , Shuying Zhou , Mouyuan Sun , Shifu Zhu , Zhen-Bo Su , Hao Liu

Observations have shown that the Eddington ratios (the ratio of the bolometric luminosity to the Eddington luminosity) in QSOs/active galactic nuclei (AGNs) cover a wide range. In this paper we connect the demography of AGNs obtained by the…

Astrophysics · Physics 2009-11-10 Qingjuan Yu , Youjun Lu , Guinevere Kauffmann
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