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Related papers: Reconstructing AGN X-ray spectral parameter distri…

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We present a new Bayesian method for reconstructing the parent distributions of X-ray spectral parameters of active galactic nuclei (AGN) in large surveys. The method uses the probability distribution function (PDF) of posteriors obtained…

High Energy Astrophysical Phenomena · Physics 2022-11-23 Lingsong Ge , Stéphane Paltani , Dominique Eckert , Mara Salvato

We present here a detailed X-ray spectral analysis of the AGN belonging to the XMM-Newton bright survey (XBS) that comprises more than 300 AGN up to redshift ~ 2.4. We performed an X-ray analysis following two different approaches: by…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 A. Corral , R. Della Ceca , A. Caccianiga , P. Severgnini , H. Brunner , F. J. Carrera , M. J. Page , A. D. Schwope

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

X-ray spectroscopy of heavily obscured Active Galactic Nuclei (AGN) offers a unique opportunity to study the circum-nuclear environment of accreting supermassive black holes (SMBHs). However, individual models describing the obscurer have…

High Energy Astrophysical Phenomena · Physics 2024-03-12 Kristína Kallová , Peter G. Boorman , Claudio Ricci

X-ray spectroscopy of active galactic nuclei (AGN) reveals key information about circumnuclear geometry. Many AGN show a narrow Fe K-alpha line at 6.4 keV and associated Compton-scattered continua, produced by primary continuum scattering…

Astrophysics of Galaxies · Physics 2025-12-25 Ingrid Vanessa Daza-Perilla , Panayiotis Tzanavaris , V. Madurga-Favieres , M. Yukita , A. Ptak , T. Yaqoob

In modeling the X-ray spectra of active galactic nuclei (AGNs), the inclination angle is a parameter that can play an important role in analyzing the X-ray spectra of AGN, but it has never been studied in detail. We present a broadband…

Astrophysics of Galaxies · Physics 2020-05-13 X. Zhao , S. Marchesi , M. Ajello , M. balokovic , T. Fischer

The cosmic X-ray background (CXB) is produced by the emission of unresolved active galactic nuclei (AGN), thus providing key information about the properties of the primary and reprocessed X-ray emission components of the AGN population.…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-28 D. Gerolymatou , S. Paltani , C. Ricci , M. Regamey

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

We constrain X-ray spectral shapes for the ensemble of AGN based on the shape of the Cosmic X-ray Background (CXB). Specifically, we rule out regions of X-ray spectral parameter space that do not reproduce the CXB in the energy range 1-100…

We present results of a high-resolution soft X-ray (0.2-2 keV) spectroscopic study of a sample of 69 nearby obscured Active Galactic Nuclei (AGN) observed with the Reflection Grating Spectrometer (RGS) on board XMM-Newton. This is the…

Astrophysics · Physics 2008-11-26 Matteo Guainazzi , Stefano Bianchi

We present an analysis of the X-ray properties of sources detected in the 13H XMM-Newton deep (200ks) field. In order to constrain the absorbed AGN population, we use extensive Monte Carlo simulations to directly compare the X-ray colours…

Astrophysics · Physics 2009-11-11 T. Dwelly , M. J. Page , N. S. Loaring , K. O. Mason , I. McHardy , K. Gunn , T. Sasseen

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

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,…

We present a detailed X-ray spectral analysis of the sources in the 1Ms catalog of the Chandra Deep Field South (CDFS) taking advantage of optical spectroscopy and photometric redshifts for 321 sources. As a default spectral model, we adopt…

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

The majority of active galactic nuclei (AGN) are obscured by large amounts of absorbing material that makes them invisible at many wavelengths. X-rays, given their penetrating power, provide the most secure way for finding these AGN. The…

We use a combination of the XMM-Newton serendipitous X-ray survey with the optical SDSS, and the infrared WISE all-sky survey in order to check the efficiency of the low X-ray to infrared luminosity selection method in finding heavily…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 E. Rovilos , I. Georgantopoulos , A. Akylas , J. Aird , D. M. Alexander , A. Comastri , A. Del Moro , P. Gandhi , A. Georgakakis , C. M. Harrison , J. R. Mullaney

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 have incorporated the description of the X-ray properties of Active Galactic Nuclei (AGNs) into a semi-analytic model of galaxy formation, adopting physically motivated scaling laws for accretion triggered by galaxy encounters. Our model…

Astrophysics · Physics 2009-11-10 N. Menci , F. Fiore , G. C. Perola , A. Cavaliere

We explore the possibility of using machine learning to estimate physical parameters directly from AGN X-ray spectra without needing computationally expensive spectral fitting. Specifically, we consider survey quality data, rather than long…

High Energy Astrophysical Phenomena · Physics 2022-06-22 M. L. Parker , M. Lieu , G. A. Matzeu
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