English
Related papers

Related papers: Parameter dependency on the public X-ray reverbera…

200 papers

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

In this work, we compare the SFRs and SFHs of AGN and non-AGN galaxies. We explore these aspects across different density fields and over three orders of magnitude in L$_X$. For that purpose, we employ X-ray AGN detected in the XMM-XXL…

Astrophysics of Galaxies · Physics 2024-06-19 G. Mountrichas , M. Siudek , O. Cucciati

X-ray spectroscopy offers an opportunity to study the complex mixture of emitting and absorbing components in the circumnuclear regions of active galactic nuclei, and to learn about the accretion process that fuels AGN and the feedback of…

High Energy Astrophysical Phenomena · Physics 2009-11-13 T. J. Turner , L. Miller

Above $\sim$3 keV, the X-ray spectrum of the active galactic nuclei (AGN) is characterized by the intrinsic continuum and compton reflection features. For type-1 AGN, several regions could contribute to the reflection. In order to…

We have studied the dependence of the AGN nuclear radio (1.4 GHz) luminosity on both the AGN 2-10 keV X-ray and the host-galaxy K-band luminosity. A complete sample of 1268 X-ray selected AGN (both type 1 and type 2) has been used, which is…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-22 A. Bonchi , F. La Franca , G. Melini , A. Bongiorno , F. Fiore

The corona is an integral component of Active Galactic Nuclei (AGN) which produces the bulk of the X-ray emission above 1--2 keV. However, many of its physical properties and the mechanisms powering this emission remain a mystery. In…

Spectral timing analyses based upon wavelet transforms provide a new means to study the variability of the X-ray emission from accreting systems, including AGN, stellar mass black holes and neutron stars, and can be used to trace the time…

High Energy Astrophysical Phenomena · Physics 2023-10-11 D. R. Wilkins

The standard alpha-disc model predicts an anti-correlation between the density of the inner accretion disc and the black hole mass times square of the accretion rate, as seen in higher mass ($M_{\rm BH}>10^{6} M_{\odot}$) active galactic…

We present a detailed comparison between the 2-10 keV hard X-ray and infrared (IR) luminosity function (LF) of active galactic nuclei (AGN). The composite X-ray to IR spectral energy distributions (SEDs) of AGN used for connecting the hard…

Astrophysics of Galaxies · Physics 2014-08-29 Yunkun Han , Benzhong Dai , Bo Wang , Fenghui Zhang , Zhanwen Han

We derive a theoretical relation between $R_{BLR}$, the size of the broad-emission-line region of active galactic nuclei, and the observed soft X-ray luminosity and spectrum. We show that in addition to the well known $R_{BLR}\sim L^{1/2}$…

Astrophysics · Physics 2007-05-23 Amri Wandel

The X-ray and mid-IR emission from active galactic nuclei (AGN) are strongly correlated. However, while various published parameterizations of this correlation are consistent with the low-redshift, local Seyfert galaxy population,…

Astrophysics of Galaxies · Physics 2015-07-15 Daniel Stern

We investigate the physical nature of active galactic nuclei (AGNs) using machine learning (ML) tools. We show that the redshift, $z$, bolometric luminosity, $L_{\rm Bol}$, central mass of the supermassive black hole (SMBH), $M_{\rm BH}$,…

Astrophysics of Galaxies · Physics 2024-05-17 Sarah Mechbal , Markus Ackermann , Marek Kowalski

The narrow Fe K$\alpha$ line is one of the main signatures of the reprocessing of X-ray radiation from the material surrounding supermassive black holes, and it has been found to be omnipresent in the X-ray spectra of active galactic nuclei…

Astrophysics of Galaxies · Physics 2015-06-19 Claudio Ricci , Yoshihiro Ueda , Stephane Paltani , Kohei Ichikawa , Poshak Gandhi , Hisamitsu Awaki

The hard X-ray emission of active galactic nuclei (AGN) is believed to originate from the hot coronae above the cold accretion discs. The hard X-ray spectral index is found to be correlated with the Eddington ratio, and the hard X-ray…

Astrophysics · Physics 2009-11-13 Xinwu Cao

Luminous accreting stellar mass and supermassive black holes produce power-law continuum X-ray emission from a compact central corona. Reverberation time lags occur due to light travel time-delays between changes in the direct coronal…

High Energy Astrophysical Phenomena · Physics 2015-06-19 P. Uttley , E. M. Cackett , A. C. Fabian , E. Kara , D. R. Wilkins

The determination of the broad (0.1-100 keV) spectra of active galaxies is crucial for understanding and discriminating among emission models, for estimating the properties of the Comptonising/reflecting region around the central black hole…

High Energy Astrophysical Phenomena · Physics 2013-02-12 Manuela Molina , L. Bassani , A. Malizia , A. Bazzano , P. Ubertini , A. J. Bird

Numerous X-ray spectral models have been developed to model emission reprocessed by the torus of an active galactic nucleus (AGN), e.g., UXCLUMPY, CTORUS, and MYTORUS. They span a range of assumed torus geometries and morphologies-some…

High Energy Astrophysical Phenomena · Physics 2021-12-15 Tathagata Saha , Alex G. Markowitz , Johannes Buchner

A thorough study of radio emission in Active Galactic Nuclei (AGN) is of fundamental importance to understand the physical mechanisms responsible for the emission and the interplay between accretion and ejection processes. High frequency…

Astrophysics of Galaxies · Physics 2020-05-27 E. Chiaraluce , F. Panessa , G. Bruni , R. D. Baldi , E. Behar , F. Vagnetti , F. Tombesi , I. McHardy

Swift intensive accretion disk reverberation mapping of four AGN yielded light curves sampled $\sim$200-350 times in 0.3-10 keV X-ray and six UV/optical bands. Uniform reduction and cross-correlation analysis of these datasets yields three…