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Related papers: The Infrared-X-ray continuum correlation in Active…

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In order to understand the interactions between active galactic nuclei (AGN) and star formation during the evolution of galaxies, we investigate 142 galaxies detected in both X-ray and 70{\mu}m observations in the COSMOS (Cosmic Evolution…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-23 Ming-Yi Lin , Yasuhiro Hashimoto , Sebastien Foucaud

It is known that the IR and X-ray luminosities of Active Galactic Nuclei (AGN) are correlated with L_{IR} ~ L_{X}. Moreover, the IR flux ratio between the 5.8 and 3.6 \mu m bands is a good distinguishing characteristic of AGN or AGN-like…

High Energy Astrophysical Phenomena · Physics 2013-08-08 P. Shalima , V. Jithesh , K. Jeena , R. Misra , S. Ravindranath , G. C. Dewangan , C. D. Ravikumar , B. R. S. Babu

We measure the correlation between sky coordinates of the Swift BAT catalogue of active galactic nuclei with the arrival directions of the highest energy cosmic rays detected by the Auger Observatory. The statistically complete, hard X-ray…

A Chandra observation of the isolated hard X-ray source XMMU J061804.3+222732, located in the region of apparent interaction of the supernova remnant IC 443 with a molecular cloud, resolved the complex structure of the source in a few…

Astrophysics · Physics 2009-11-10 A. M. Bykov , F. Bocchino , G. G. Pavlov

We present modeling and interpretation of the continuum and emission lines for a sample of 51 unobscured Type 1 active galactic nuclei (AGN). All of these AGNs have high quality spectra from both XMM-Newton and Sloan Digital Sky Survey…

High Energy Astrophysical Phenomena · Physics 2015-05-30 C. Jin , M. Ward , C. Done , J. M. Gelbord

The question of the origin of the hard X-ray/soft gamma-ray emission in Centaurus A (Cen A) persists despite decades of observations. Results from X-ray instruments suggest a jet origin since the implied electron temperature (kT_e) would…

High Energy Astrophysical Phenomena · Physics 2023-10-03 James Rodi , E. Jourdain , M. Molina , J. -P. Roques

The relation between X-ray luminosity and near-infrared luminosity for early-type galaxies has been examined. Near-infrared (NIR) luminosities should provide a superior measure of stellar mass compared to optical luminosities used in…

Astrophysics · Physics 2009-11-11 S. C. Ellis , Ewan O'Sullivan

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

The origin of soft X-ray excess emission from type 1 active galactic nuclei has remained a major problem for the last two decades. It has not been possible to distinguish alternative models for the soft excess emission despite the excellent…

Astrophysics · Physics 2009-11-13 G. C. Dewangan , R. E. Griffiths , A. R. Rao , Surajit Dasgupta

The X-ray luminosity function (XLF) of galaxies is dominated by AGN (classified by their optical spectra) above Lx=10**42 erg/s, below this value by normal galaxies. The X-ray flux of AGN at low X-ray luminosity therefore contains…

Astrophysics · Physics 2007-05-23 I. Lehmann , G. Hasinger , A. D. Schwope , Th. Boller

A unique, essentially complete sample of 22 QSOs, with high quality soft X-ray spectra from ROSAT, as well as HST and optical spectrophotometry from below Ly-alpha to above H-alpha, is being used to investigate the relationships among the…

Astrophysics · Physics 2007-05-23 Beverley J. Wills , M. S. Brotherton , A. Laor , D. Wills , B. J. Wilkes , G. J. Ferland

We discuss recent results on the Seyfert spectral variability. Their observed high energy variability is generally consistent with X-ray spectral slop fluctuations produced by change of the soft photon luminosity in the sense that spectra…

Astrophysics · Physics 2007-05-23 P. O. Petrucci

A significant correlation between FeKalpha line energy and X-ray spectral slope has been discovered among radio-quiet active galactic nuclei. The ionization stage of the bulk of the FeKalpha emitting material is not the same in all active…

Astrophysics · Physics 2009-11-07 Gulab Chand Dewangan

Most Active Galactic Nuclei (AGN) in the local Universe are obscured. In these obscured AGN an excess is usually observed in the soft X-rays below ~2 keV above the absorbed X-ray continuum. This spectral component is associated with the…

High Energy Astrophysical Phenomena · Physics 2023-10-18 Jeffrey McKaig , Claudio Ricci , Stéphane Paltani , K. K. Gupta , Nicholas P. Abel , Y. Ueda

We study the UV spectra of narrow-line Seyfert~1 (NLSy1) galaxies and compare them with ``normal'' AGN. Similar to their optical lines, the NLSy1s show narrower UV lines. They are also characterized by weaker CIV 1549, CIII] 1909, and…

Astrophysics · Physics 2009-10-31 J. Kuraszkiewicz , B. J. Wilkes , B. Czerny , S. Mathur

We present a detailed description of the first direct measurement of the spatial correlation function of X-ray selected AGN. This result is based on an X-ray flux-limited sample of 219 AGN discovered in the contiguous 80.7 deg^2 region of…

Astrophysics · Physics 2009-11-10 C. R. Mullis , J. P. Henry , I. M. Gioia , H. Boehringer , U. G. Briel , W. Voges , J. P. Huchra

We systematically investigate the near- (NIR) to far-infrared (FIR) photometric properties of a nearly complete sample of local active galactic nuclei (AGN) detected in the Swift/Burst Alert Telescope (BAT) all-sky ultra hard X-ray (14-195…

We build detailed composite models of photoionization and shock ionization based on the SUMA code to reproduce emission lines emitted from the Narrow Line Regions (NLR) of Seyfert 2 nuclei. The aim of this work is to investigate diagram AGN…

Astrophysics of Galaxies · Physics 2020-12-09 O. L. Dors , M. Contini , R. A. Riffel , E. Perez-Montero , A. C. Krabbe , M. V. Cardaci , G. F. Hagele

The EGRET results for gamma-ray intensities in and near the Galactic Plane have been analysed in some detail. Attention has been concentrated on energies above 1 GeV and the individual intensities in a $4^\circ$ longitude bin have been…

Astrophysics · Physics 2009-11-11 A. D. Erlykin , A. W. Wolfendale

Over the last 3 yrs, the Galactic center (GC) region has been monitored with the Chandra X-Ray Observatory. With 11 Chandra observations through 2002 June, the total effective exposure reaches ~590 ks, providing significant photon…

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