English
Related papers

Related papers: Toward a Unified AGN Structure

200 papers

In this work, which is a continuation of Castell\'o-Mor et al. (2016), we present new X-ray and infrared (IR) data for a sample of active galactic nuclei (AGN) covering a wide range in Eddington ratio over a small luminosity range. In…

Astrophysics of Galaxies · Physics 2017-02-01 Núria Castelló-Mor , Shai Kaspi , Hagai Netzer , Pu Du , Chen Hu , Luis C. Ho , Jin-Ming Bai , Wei-Hao Bian , Ye-Fei Yuan , Jian-Min Wang

We investigate the relation between the two modes of outflow (wind and jet) in radio-loud active galactic nuclei (AGN). For this study we have carried out a systematic and homogeneous analysis of XMM-Newton spectra of a sample of 16…

High Energy Astrophysical Phenomena · Physics 2019-05-08 Missagh Mehdipour , Elisa Costantini

Highly-ionized fast accretion-disk winds have been suggested as an explanation for a variety of observed absorption and emission features in the X-ray spectra of Active Galactic Nuclei. Simple estimates have suggested that these flows may…

High Energy Astrophysical Phenomena · Physics 2015-05-18 S. A. Sim , L. Miller , K. S. Long , T. J. Turner , J. N. Reeves

Our goal is to characterize AGN populations by comparing their X-ray and optical classifications. We present a sample of 99 spectroscopically identified X-ray point sources in the XMM-LSS survey which are significantly detected in the…

Black hole accretion disks appear to produce invariably plasma outflows that result in blue-shifted absorption features in their spectra. The X-ray absorption-line properties of these outflows are quite diverse, ranging in velocity from…

High Energy Astrophysical Phenomena · Physics 2017-03-08 Keigo Fukumura , Demosthenes Kazanas , Chris Shrader , Ehud Behar , Francesco Tombesi , Ioannis Contopoulos

We propose that changing-look AGN transitions arise from variations in the size of the inner ADAF disk. The AGN accretion disk consists of an outer thin disk and an inner thick ADAF component, whose size is intrinsically unstable and…

High Energy Astrophysical Phenomena · Physics 2026-05-19 Chun Xu

Ultra-fast outflows (UFOs) are highly ionized, mildly relativistic winds seen in the X-ray spectra of active galactic nuclei (AGN) and are thought to contribute to AGN feedback and galaxy evolution. We investigate UFO signatures by…

We investigate the radial structure of active galactic nuclei (AGN) dusty tori by forward-modeling mid-infrared (MIR) spectra observed with JWST/MIRI-MRS for a sample of 25 AGN. We develop a physically motivated three dimensional radiative…

Astrophysics of Galaxies · Physics 2026-03-17 Ruiyu Pan , Arkaprabha Sarangi

AGN are known to have complex X-ray spectra that depend on both the properties of the accreting SMBH (e.g. mass, accretion rate) and the distribution of obscuring material in its vicinity ("torus"). Often however, simple and even unphysical…

High Energy Astrophysical Phenomena · Physics 2014-05-08 J. Buchner , A. Georgakakis , K. Nandra , L. Hsu , C. Rangel , M. Brightman , A. Merloni , M. Salvato , J. Donley , D. Kocevski

We present the results from the spectral analysis of more than 7,500 RXTE spectra of 10 AGN, which have been observed by RXTE regularly over a long period of time ~ 7-11 years. These observations most probably sample most of the flux and…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-02 M. A. Sobolewska , I. E. Papadakis

We investigate the link between optical obscuration and X-ray absorption in active galactic nuclei (AGN) by combining X-ray spectroscopy from 4XMM-DR11 with SDSS DR16Q spectroscopy. Bayesian X-ray spectral fits were obtained within the…

Astrophysics of Galaxies · Physics 2026-04-22 G. Mountrichas , F. J. Carrera , E. Quintin , A. Viitanen , A. Corral , N. Webb

The X-ray Background (XRB) probably originates from the integrated X-ray emission of active galactic nuclei (AGN). Modelling of its flat spectrum implies considerable absorption in most AGN. Compton down-scattering means that sources in…

Astrophysics · Physics 2009-10-31 A. C. Fabian , K. Iwasawa

Unification Models of Active Galactic Nuclei postulate that all the observed differences between Type 1 and Type 2 objects are due to orientation effects with respect to the line-of-sight to the observer. The key ingredient of these models…

Astrophysics of Galaxies · Physics 2015-06-03 Stefano Bianchi , Roberto Maiolino , Guido Risaliti

The SWIFT gamma ray observatory's Burst Alert Telescope (BAT) has detected a sample of active galactic nuclei (AGN) based solely on their hard X-ray flux (14-195 keV). In this paper, we present for the first time {\it XMM-Newton} X-ray…

Astrophysics · Physics 2009-11-13 Lisa M. Winter , Richard F. Mushotzky , Jack Tueller , Craig Markwardt

Low-luminosity active galactic nuclei (LLAGNs) are generally believed to be powered by an inner radiatively inefficient, advection-dominated accretion flow (ADAF), an outer truncated thin disk, and a jet. Maoz (2007) recently challenged…

High Energy Astrophysical Phenomena · Physics 2015-05-20 Zhaolong Yu , Feng Yuan , Luis Ho

Feedback from accreting SMBHs is often identified as the main mechanism responsible for regulating star-formation in AGN host galaxies. However, the relationships between AGN activity, radiation, winds, and star-formation are complex and…

We have studied several neutron star high-mass X-ray binaries (HMXBs) with super-giant (SG) companions using a wind-fed binary model associated with the magnetic field. By using the concept of torque balance, the magnetic field parameter…

High Energy Astrophysical Phenomena · Physics 2023-07-27 Ali Taani , Shigeyuki Karino , Liming Song , Chengmin Zhang , Sylvain Chaty

Winds arising from galaxies, star clusters, and active galactic nuclei are crucial players in star and galaxy formation, but it has proven remarkably difficult to use observations of them to determine physical properties of interest,…

Astrophysics of Galaxies · Physics 2017-08-30 Mark R. Krumholz , Todd A. Thompson , Eve C. Ostriker , Crystal L. Martin

We present optical and X-ray data for a sample of serendipitous XMM-Newton sources that are selected to have 0.5-2 keV vs 2-4.5 keV X-ray hardness ratios which are harder than the X-ray background. The sources have 2-4.5 keV X-ray flux >=…

We have found empirically that the radio loudness of AGN can be understood as function of both the X-ray and optical luminosity. This way of considering the radio loudness was inspired by the hardness-intensity diagrams for X-ray binaries,…

Astrophysics · Physics 2008-11-26 Sebastian Jester , Elmar Koerding , Rob Fender
‹ Prev 1 3 4 5 6 7 10 Next ›