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Related papers: A structure function analysis of VST-COSMOS AGN

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The dependence of the long-term optical/UV variability on the spectral and the fundamental physical parameters for radio-quiet active galactic nuclei (AGNs) is investigated. The multi-epoch repeated photometric scanning data in the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Y. L. Ai , W. Yuan , H. Y. Zhou , T. G. Wang , X. -B. Dong , J. G. Wang , H. L. Lu

We investigate the properties of a variability-selected complete sample of AGN in order to identify the mechanisms which cause large amplitude X-ray variability on time scales of years. A complete sample of 24 sources was constructed, from…

High Energy Astrophysical Phenomena · Physics 2016-08-09 N. L. Strotjohann , R. D. Saxton , R. L. C. Starling , P. Esquej , A. M. Read , P. A. Evans , G. Miniutti

Low luminosity active galactic nuclei (LLAGN) probe accretion physics in the low Eddington regime and can provide additional clues about galaxy evolution. AGN variability is ubiquitous and thus provides a reliable tool for finding AGN. We…

The active galactic nuclei X-ray luminosity function traces actively accreting supermassive black holes and is essential for the study of the properties of the active galactic nuclei (AGN) population, black hole evolution, and galaxy-black…

In this work, we study the relation of cosmic environment and morphology with the star-formation (SF) and the stellar population of galaxies. Most importantly, we examine if this relation differs for systems with active and non-active…

Astrophysics of Galaxies · Physics 2023-07-12 G. Mountrichas , G. Yang , V. Buat , B. Darvish , M. Boquien , Q. Ni , D. Burgarella , L. Ciesla

[Abbreviated] We search for scaling relations between the fundamental AGN parameters and rest-frame UV/optical variability properties for a sample of $\sim$90 X-ray selected AGNs covering a wide redshift range from the XMM-COSMOS survey,…

Astrophysics of Galaxies · Physics 2016-01-13 T. Simm , M. Salvato , R. Saglia , G. Ponti , G. Lanzuisi , K. Nandra , R. Bender

Context. Variability is a ubiquitous feature of active galactic nuclei (AGNs), and the characterisation of the variability is crucial to constrain its physical mechanism and proper applications in AGN studies. The advent of all-sky and…

High Energy Astrophysical Phenomena · Physics 2025-06-04 Heechan Yuk , Xinyu Dai

The morphological study is crucial to investigate the connections between active galactic nuclei (AGN) activities and the evolution of galaxies. Substantial studies have found that radiative-mode AGNs primarily reside in disk galaxies,…

Astrophysics of Galaxies · Physics 2022-02-09 Yuxing Zhong , Akio K. Inoue , Satoshi Yamanaka , Toru Yamada

One of the most peculiar characteristics of Active Galactic Nuclei (AGN) is their variability over all wavelengths. This property has been used in the past to select AGN samples and is foreseen to be one of the detection techniques applied…

We use $\sim 1,000$ X-ray sources in the COSMOS-Legacy survey and study the position of the AGN relative to the star forming main sequence (MS). We also construct a galaxy (non-AGN) reference sample that includes $\sim 90,000$ sources. We…

Astrophysics of Galaxies · Physics 2022-05-18 G. Mountrichas , V. A. Masoura , E. M. Xilouris , I. Georgantopoulos , V. Buat , E. -D. Paspaliaris

Unraveling the growth of supermassive black holes and their connection to host galaxies requires disentangling the Active Galactic Nuclei (AGN) emission from that of the stellar populations. When an AGN spectrum is observed at different…

We present results of recurrence analysis of 46 active galactic nuclei (AGN) using light curves from the 157-month catalog of the Swift Burst Alert Telescope (BAT) in the 14-150 keV band. We generate recurrence plots and compute recurrence…

High Energy Astrophysical Phenomena · Physics 2022-11-28 R. A. Phillipson , M. S. Vogeley , P. T. Boyd

We are conducting an archival Swift program to measure multiwavelength variability in active galactic nuclei (AGN). This variability information will provide constraints on the geometry, physical conditions and processes of the structures…

High Energy Astrophysical Phenomena · Physics 2015-05-21 Jonathan Gelbord , Caryl Gronwall , Dirk Grupe , Dan Vanden Berk , Jian Wu

Variability is a property shared by virtually all active galactic nuclei (AGNs), and was adopted as a criterion for their selection using data from multi epoch surveys. Low Luminosity AGNs (LLAGNs) are contaminated by the light of their…

Astrophysics · Physics 2009-11-13 D. Trevese , K. Boutsia , F. Vagnetti , E. Cappellaro , S. Puccetti

We study the morphology of the central region of a sample of Active Galactic Nuclei (AGN) and a ``control'' sample of normal galaxies using archival observations of the WFPC2 instrument onboard the Hubble Space Telescope (HST). We use the…

Astrophysics · Physics 2009-11-07 E. M. Xilouris , I. E. Papadakis

We study the properties of 975 active galactic nuclei (AGN) selected by variability in the Pan-STARRS1 Medium-Deep Survey. Using complementary multi wavelength data from the ultraviolet to the far-infrared, we use SED fitting to determine…

Astrophysics of Galaxies · Physics 2016-07-27 S. Heinis , S. Gezari , S. Kumar , W. S. Burgett , H. Flewelling , M. E. Huber , N. Kaiser , R. J. Wainscoat , C. Waters

Motivated by upcoming photometric and spectroscopic surveys (Vera C. Rubin Observatory Legacy Survey of Space and Time (LSST), Manuakea Spectroscopic Explorer), we design the statistical proxies to measure the cadence effects on active…

With the advent of GRAVITY+, the upgrade to the beam combiner GRAVITY at the Very Large Telescope Interferometer (VLTI), fainter and higher redshift active galactic nuclei (AGNs) are becoming observable, opening an unprecedented opportunity…

Under the unified model for active galactic nuclei (AGNs), narrow-line (Type 2) AGNs are, in fact, broad-line (Type 1) AGNs but each with a heavily obscured accretion disk. We would therefore expect the optical continuum emission from Type…

Using the wide multi-band photometry available in the COSMOS field we explore the host galaxy properties of a large sample of Active Galactic Nuclei (AGN) obtained by combining X-ray and optical spectroscopic selections. Based on a careful…