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We analyse the spectra of the archival XMM-Newton data of the Seyfert 1 AGN Zw 229.015 in the energy range $0.3 - 10.0$ keV. When fitted with a simple power-law, the spectrum shows signatures of weak soft excess below 1.0 keV. We find that…

Astrophysics of Galaxies · Physics 2016-12-21 Oluwashina Adegoke , Suvendu Rakshit , Banibrata Mukhopadhyay

Changing-state active galactic nuclei (CSAGNs) exhibit rapid variability, with mass accretion rates that can change by several orders of magnitude in a few years. This provides us with a unique opportunity to study the evolution of the…

Active galactic nuclei (AGNs) exhibit strong variability across the electromagnetic spectrum on a wide range of timescales, particularly in X-rays where fluctuations are both rapid and high amplitude. Power spectral density (PSD) analysis…

Astrophysics of Galaxies · Physics 2026-03-13 V. A. Diamantopoulos , I. E. Papadakis , A. Akylas , A. Zoghbi , E. Kammoun , B. Rani

The origin of the soft excess seen in many AGN below ~1 keV is still an unsolved problem. It is unlikely to represent a true continuum component as its characteristic 'temperature' shows a remarkable constancy over a wide range of AGN…

Astrophysics · Physics 2009-11-11 Marek Gierlinski , Chris Done

The relation between the 2-10 keV, long term, excess variance and AGN black hole mass is considered in this work. A significant anti-correlation is found between these two quantities in the sense that the excess variance decreases with…

Astrophysics · Physics 2009-11-10 I. E. Papadakis

We perform time-dependent, 2DHD numerical simulations to study the dynamics of a slowly rotating accretion flow from sub-pc to pc scales under the irradiation from the central AGN. Compared to previous work, we improve the calculation of…

High Energy Astrophysical Phenomena · Physics 2015-06-15 Chao Liu , Feng Yuan , Jeremiah P. Ostriker , Zhaoming Gan , Xiaohong Yang

We study the link between the X-ray emission in radio-quiet AGNs and the accretion rate on the central Supermassive Black Hole using a statistically well-defined and representative sample of 71 type 1 AGNs extracted from the XMM-Newton…

High Energy Astrophysical Phenomena · Physics 2015-06-15 R. Fanali , A. Caccianiga , P. Severgnini , R. Della Ceca , E. Marchese , F. J. Carrera , A. Corral , S. Mateos

(Abridged) We measure and analyze the energy, momentum, and mass feedback efficiencies due to radiation from AGN in relatively large scale outflows. Our measurements are based on the axisymmetric and time-dependent radiation-hydrodynamical…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-11 Ryuichi Kurosawa , Daniel Proga , Kentaro Nagamine

We study the X-ray power spectrum of Active Galactic Nuclei (AGN) to investigate whether Seyfert I and II power spectra are similar or not, whether the AGN variability depends on black hole mass and accretion rate, and to compare the AGN…

Astrophysics of Galaxies · Physics 2024-05-08 I. E. Papadakis , V. Binas-Valavanis

We present a detailed study of ionized outflows in a large sample of ~650 hard X-ray detected AGN. Using optical spectroscopy from the BAT AGN Spectroscopic Survey (BASS) we are able to reveal the faint wings of the [OIII] emission lines…

The origin of outflow in narrow-line region (NLR) of active galactic nucleus (AGN) is studied in this paper by focusing on the relationship between the [\ion{O}{3}]$\lambda$5007 line profile and the hard X-ray (in a bandpass of 2-10 keV)…

Astrophysics of Galaxies · Physics 2016-03-16 J. Wang , D. W. Xu , J. Y. Wei

Active galactic nuclei (AGN) emit radiation via accretion across the entire energy spectrum. While the standard disk and corona model can somewhat describe this emission, it fails to predict specific features such as the soft X-ray excess,…

We perform simulations to study the effects of active galactic nuclei (AGNs) radiation and wind feedback on the properties of slowly rotating accretion flow at parsec scale. We find that when only radiative feedback is considered, outflows…

High Energy Astrophysical Phenomena · Physics 2019-09-11 De-Fu Bu , Xiao-Hong Yang

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

Accreting supermassive black holes at the centres of galaxies are the engine of active galactic nuclei (AGN). X-ray light curves of unabsorbed AGN show dramatic random variability on timescales ranging from seconds to years. The power…

High Energy Astrophysical Phenomena · Physics 2025-10-29 Mehdy Lefkir , Simon Vaughan , Mike Goad , Daniela Huppenkothen , Phil Uttley

We have constrained the extragalactic source count distributions over a broad range of X-ray fluxes and in various energy bands to test whether the predictions from X-ray background synthesis models agree with the observational constraints…

We study the energetics of the accretion-induced outflow and then plausible jet around black holes/compact objects using a newly developed disc-outflow coupled model. Inter-connecting dynamics of outflow and accretion essentially upholds…

High Energy Astrophysical Phenomena · Physics 2009-09-28 Shubhrangshu Ghosh , Banibrata Mukhopadhyay , Vinod Krishan , Manoranjan Khan

Energetic ionized gas outflows driven by active galactic nuclei (AGN) have been studied as a key phenomenon related to AGN feedback. To probe the kinematics of the gas in the narrow line region, [O III] ${\lambda}$5007 has been utilized in…

Astrophysics of Galaxies · Physics 2017-08-22 Daeun Kang , Jong-Hak Woo , Hyun-Jin Bae

The detection of X-ray narrow spectral features in the 5-7 keV band is becoming increasingly more common in AGN observations, thanks to the capabilities of current X-ray satellites. Such lines, both in emission and in absorption, are mostly…

Astrophysics · Physics 2008-11-26 A. L. Longinotti , S. Bianchi , M. Guainazzi , J. Roa-Llamazares , M. Santos-Lleo

We present the study of the gas kinematics in narrow-line regions (NLRs) of 2,009 type-2 AGNs at $z<0.34$. We construct the [O III]$\lambda$5007 emission-line images using publicly available broadband images from the Sloan Digital Sky…

Astrophysics of Galaxies · Physics 2025-05-07 Kantapon Jensangjun , Suraphong Yuma
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