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Related papers: An Iwasawa-Taniguchi Effect for Compton-thick Acti…

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We present a large sample of infrared-luminous candidate active galactic nuclei (AGNs) that lack X-ray detections in Chandra, XMM-Newton, and NuSTAR fields. We selected all optically detected SDSS sources with redshift measurements,…

Heavily obscured active galactic nuclei (AGNs) play an important role in contributing to the cosmic X-ray background (CXRB). However, the AGNs found in deep X-ray surveys are often too weak to allow direct measurement of the column density…

High Energy Astrophysical Phenomena · Physics 2015-05-20 Tahir Yaqoob , Kendrah D. Murphy

The Swift/BAT nine-month survey observed 153 AGN, all with ultra-hard X-ray BAT fluxes in excess of 10^-11 erg cm^-2 s^-1 and an average redshift of 0.03. Among them, four of the most luminous BAT AGN (44.73 < Log L(BAT) < 45.31) were…

High Energy Astrophysical Phenomena · Physics 2015-06-15 V. Fioretti , L. Angelini , R. F. Mushotzky , M. Koss , G. Malaguti

The X-ray spectra of active galactic nuclei (AGN) unveil properties of matter around the super massive black hole (SMBH). We investigate the X-ray spectra of AGN focusing on Compton reflection and fluorescence, important processes of…

Astrophysics of Galaxies · Physics 2014-08-12 S. Falocco , F. J. Carrera , X. Barcons , G. Miniutti , A. Corral

We performed near-diffraction-limited (~0.4 FWHM) N-band imaging of one of the nearest Active Galactic Nucleus (AGN) in M51 with 8.2m Subaru telescope to study the nuclear structure and spectral energy distribution (SED) at 8-13 um. We…

Astrophysics of Galaxies · Physics 2017-02-01 Youichi Ohyama , Satoki Matsushita , Nagisa Oi , Ai-Lei Sun

We present the 2--78 keV spectral analysis of the deep NuSTAR and XMM-Newton observation of a nearby Seyfert 2 galaxy, ESO 116-G018, which is selected as a candidate Compton-thick (CT-) active galactic nucleus (AGN) based on a previous…

Astrophysics of Galaxies · Physics 2019-02-28 X. Zhao , S. Marchesi , M. Ajello

The X-ray background (XRB) is due to the aggregate of active galactic nuclei (AGN), which peak in activity at z~1 and is often modeled as the sum of different proportions of unabsorbed, moderately- and heavily-absorbed AGN. We present the…

High Energy Astrophysical Phenomena · Physics 2015-06-16 Ranjan V. Vasudevan , Richard F. Mushotzky , Poshak Gandhi

The anti-correlations between the equivalent widths of emission lines and the continuum luminosity in AGNs, known as the Baldwin effect are well established for broad lines, but are less well studied for narrow lines. In this paper we…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Kai Zhang , Ting-Gui Wang , C. Martin Gaskell , Xiao-Bo Dong

Recent observations of nearby Compton thick (CT) active galactic nuclei (AGNs) with Chandra have resolved hard (>3 keV) X-ray emission extending out from the central supermassive black hole to kiloparsec scales, challenging the long-held…

Astrophysics of Galaxies · Physics 2020-03-25 Mackenzie L. Jones , G. Fabbiano , Martin Elvis , A. Paggi , M. Karovska , W. P. Maksym , A. Siemiginowska , J. Raymond

An empirical forward-modeling framework is developed to interpret the multiwavelength properties of Active Galactic Nuclei (AGN) and provide insights into the overlap and incompleteness of samples selected at different parts of the…

High Energy Astrophysical Phenomena · Physics 2020-10-21 Antonis Georgakakis , Angel Ruiz , Stephanie M. LaMassa

We examine the accretion properties in a sample of 42 hard (3-60keV) X-ray selected nearby broad-line AGNs. The energy range in the sample is harder than that usually used in the similar previous studies. These AGNs are mainly complied from…

Astrophysics · Physics 2011-02-19 J. Wang , Y. F. Mao , J. Y. Wei

We construct the rest-frame 2--10 keV intrinsic X-ray luminosity function of Active Galactic Nuclei (AGNs) from a combination of X-ray surveys from the all-sky Swift BAT survey to the Chandra Deep Field-South. We use ~3200 AGNs in our…

We study the hard-X-ray spectral properties of ten highly luminous radio-quiet (RQ) active galactic nuclei (AGNs) at z=1.3-3.2, including new XMM-Newton observations of four of these sources. We find a significant correlation between the…

Astrophysics · Physics 2009-11-13 Ohad Shemmer , W. N. Brandt , Hagai Netzer , Roberto Maiolino , Shai Kaspi

We study the Baldwin Effect (BE) in 96 core-jet blazars with optical and ultraviolet spectroscopic data from a radio-loud AGN sample obtained from the MOJAVE 2 cm survey. A statistical analysis is presented of the equivalent widths…

We suggest that the growth of the central black hole in active galactic nuclei (AGN) due to the matter accreted over the AGN lifetime causes an evolution of the luminosity and spectrum. In a previous paper we have shown that the effective…

Astrophysics · Physics 2009-10-31 Amri Wandel

Compton-thick active galactic nuclei (CT-AGNs), which are defined by column density $\mathrm{N_H} \geqslant 1.5 \times 10^{24} \ \mathrm{cm}^{-2}$, emit feeble X-ray radiation, even undetectable by X-ray instruments. Despite this, the X-ray…

Astrophysics of Galaxies · Physics 2025-05-28 Rui Zhang , Xiaotong Guo , Qiusheng Gu , Guanwen Fang , Jun Xu , Hai-Cheng Feng , Yongyun Chen , Rui Li , Nan Ding , Hongtao Wang

X-ray fluorescent lines are unique features of the reflection spectrum of the torus when irradiated by the central AGN. Their intrinsic line width can be used to probe the line-emitting region. Previous studies have focused on the Fe Ka…

High Energy Astrophysical Phenomena · Physics 2016-04-20 Jiren Liu

We present the results of the broadband X-ray spectral analysis of simultaneous NuSTAR and XMM-Newton observations of four nearby Compton-thick active galactic nuclei (AGN) candidates selected from the Swift-Burst Alert Telescope (BAT)…

We have studied the nature and origin of the soft X-ray excess detected in the interesting changing-look AGN (CLAGN) Mrk~590 using two decades of multi-wavelength observations from \xmm{}, \suzaku{}, \swift{} and \nustar{}. In the light of…

High Energy Astrophysical Phenomena · Physics 2022-09-30 Ritesh Ghosh , Sibasish Laha , Kunal Deshmukh , Varun Bhalerao , Gulab C. Dewangan , Ritaban Chatterjee

Low ionisation nuclear emission-line region (LINER) nuclei have been claimed to be different than other active galactic nuclei (AGN) due to the presence of complex absorbing structures along the line-of-sight and/or an inefficient mode of…

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