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Related papers: Absorption Measure Distribution in AGN

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We present a systematic investigation of extremely X-ray variable active galactic nuclei (AGNs) in the $\approx 5.3~{\rm deg}^2$ XMM-SERVS XMM-LSS region. Eight variable AGNs are identified with rest-frame 2 keV flux density variability…

Astrophysics of Galaxies · Physics 2025-03-03 Zijian Zhang , Bin Luo , Linhua Jiang , W. N. Brandt , Jian Huang , Qingling Ni

In recent years it has become clear that understanding the absorption present in AGN is essential given its bearing on unification models. We present the most recent XMM-Newton observation of Mrk 6, with the goal of understanding the nature…

Astrophysics · Physics 2009-11-11 N. J. Schurch , R. E. Griffiths , R. S. Warwick

Adopting the hypothesis that the nonthermal emission of Active Galactic Nuclei (AGN) is primarily due to the acceleration of protons, we construct a simple model in which the interplay of acceleration and losses can be studied together with…

Astrophysics · Physics 2008-02-03 A. Mastichiadis J. G. Kirk

Active Galactic Nuclei (AGN) are highly energetic astrophysical sources powered by accretion onto supermassive black holes in galaxies, which present unique observational signatures covering the full electromagnetic spectrum (and more) over…

High Energy Astrophysical Phenomena · Physics 2023-04-05 Stefano Bianchi , Vincenzo Mainieri , Paolo Padovani

X-ray absorption and emission lines now serve as powerful diagnostics of the outflows from active galaxies. Detailed X-ray line studies of outflows have recently been enabled for a significant number of active galaxies via the grating…

Astrophysics · Physics 2009-11-07 W. N. Brandt , S. Kaspi

We review the continuum emission of Active Galactic Nuclei (AGN) over the entire electromagnetic spectrum. After a brief historical introduction, we describe the main spectral properties of unobscured AGN, discussing the selection biases…

Astrophysics · Physics 2016-01-27 G. Risaliti , M. Elvis

Variable X-ray absorption has been observed in active galactic nuclei (AGN) on several time scales. Observations allow us to identify the absorber with clouds associated either with the clumpy torus (parsec scales, long timescales) or with…

High Energy Astrophysical Phenomena · Physics 2018-10-18 Mario Sanfrutos , Giovanni Miniutti , Michal Dovčiak , Beatriz Agís-González

Many studies have considered the roles of clouds, outflows, and turbulence in producing the broad emission and absorption lines in the spectra of active galactic nuclei (AGNs). However, these are often treated as separate or even competing…

Astrophysics of Galaxies · Physics 2019-12-10 Tim Waters , Hui Li

Modeling the spectral energy distribution (SED) of active galactic nuclei (AGN) plays a very important role in constraining modern cosmological simulations of galaxy formation. Here, we utilize an advanced supermassive black hole (SMBH)…

Astrophysics of Galaxies · Physics 2026-03-23 Tong Su , Qi Guo , Erlin Qiao , Wenxiang Pei , Luis C. Ho , Cedric G. Lacey

We present the broad-band Spectral Energy Distributions (SEDs) of the largest available highly (72%) complete spectroscopic sample of mid-infrared (MIR) selected galaxies and AGN at intermediate redshift. The sample contains 203…

We model the broadband (optical/UV and X-ray) continuum spectrum of the "changing-look" active galactic nucleus (AGN) Mrk 1018 as it fades from Seyfert 1 to 1.9 in $\sim 8$ years. The brightest spectrum, with Eddington ratio $L/L_{\rm…

Astrophysics of Galaxies · Physics 2018-08-08 Hirofumi Noda , Chris Done

The discovery of changing-look active galactic nuclei (CL AGNs), with appearance and disappearance of broad emission lines and/or with strong variation of line-of-sight column density within a few years, challenges the AGN unification…

Astrophysics of Galaxies · Physics 2019-12-10 Hao liu , Qingwen Wu , Bing Lyu , Zhen Yan

Aims: Active Galactic Nuclei are known to be variable throughout the electromagnetic spectrum. An energy domain poorly studied in this respect is the hard X-ray range above 20 keV. Methods: The first 9 months of the Swift/BAT all-sky survey…

We aim to explore the bubble nature of the exotic nucleus $^{20}$N within the microscopic antisymmetrized molecular dynamics (AMD) approach. Constraining its structural parameters, we analyse its static properties. Subsequently, we use the…

Nuclear Theory · Physics 2023-02-15 V. Choudhary , M. Dan , R. Chatterjee , M. Kimura , W. Horiuchi , Shubhchintak , G. Singh

We analyze the broadband photometric light curves of Seyfert 1 galaxies from the Sergeev et al. (2005) sample and find that a) perturbations propagating across the continuum emitting region are a general phenomenon securely detected in most…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Doron Chelouche

Radiation pressure-driven outflows from luminous accreting supermassive black holes are an important part of active galactic nucleus (AGN) feedback. The effective Eddington limit, based on absorption of radiation by dust, not electron…

Astrophysics of Galaxies · Physics 2022-11-16 N. Arakawa , A. C. Fabian , G. J. Ferland , W. Ishibashi

We present a detailed characterization of the X-ray spectral properties of 761 type 1 AGN, selected from a cross-correlation of the SDSS DR5 quasar catalogue and the incremental version of the second XMM-Newton serendipitous X-ray source…

High Energy Astrophysical Phenomena · Physics 2015-05-28 A. E. Scott , G. C. Stewart , S. Mateos , D. M. Alexander , S. Hutton , M. J. Ward

Our goal is to probe the populations of obscured and unobscured AGN investigating their optical-IR and X-ray properties as a function of X-ray flux, luminosity and redshift within a hard X-ray selected sample of 136 X-ray sources in the XMM…

We present X-ray and multiwavelength studies of a sample of eight high-luminosity active galactic nuclei (AGNs) with disc-like H\beta emission-line profiles selected from the Sloan Digital Sky Survey Data Release 7. These sources have…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 B. Luo , W. N. Brandt , M. Eracleous , Jian Wu , P. B. Hall , A. Rafiee , D. P. Schneider , Jianfeng Wu

Ionised gas kinematics provide crucial evidence of the impact that active galactic nuclei (AGN) have in regulating star formation in their host galaxies. Although the presence of outflows in AGN host galaxies has been firmly established,…