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For a significant number of the sources detected at high energies (>10 keV) by the INTEGRAL/IBIS and Swift/BAT instruments there is either a lack information about them in the 2-10 keV range or they are totally unidentified. Herein, we…

Astrophysics · Physics 2009-11-13 A. Malizia , R. Landi , L. Bassani , A. J. Bird , M. Molina , A. De Rosa , M. Fiocchi , N. Gehrels , J. Kennea , M. Perri

Aims: The unification scheme of Seyfert galaxies predicts that the observed differences between type 1 and type 2 Seyfert galaxies are solely due to the differing orientations of the toroidal-shaped obscuring material around AGN. The…

High Energy Astrophysical Phenomena · Physics 2015-03-17 Veeresh Singh , Prajval Shastri , Guido Risaliti

We present and discuss the high energy (E>4 keV) XMM-Newton spectrum of the Seyfert 2 galaxy, NGC 1068. Possible evidence for flux variability in both the neutral and ionized reflectors with respect to a BeppoSAX observation taken 3.5 years…

Astrophysics · Physics 2009-11-10 Giorgio Matt , Stefano Bianchi , Matteo Guainazzi , Silvano Molendi

We use hard X-ray data for an "optimal" sample of Seyfert 2 galaxies to derive the distribution of the gaseous absorbing column densities among obscured active nuclei in the local Universe. Of all Seyfert 2 galaxies in the sample, 75% are…

Astrophysics · Physics 2009-10-31 G. Risaliti , R. Maiolino , M. Salvati

X-ray variability is very common in active galactic nuclei (AGN), but these variations may not occur similarly in different families of AGN. We aim to disentangle the structure of low ionization nuclear emission line regions (LINERs)…

Astrophysics of Galaxies · Physics 2016-06-15 Lorena Hernandez-Garcia , Josefa Masegosa , Omaira Gonzalez-Martin , Isabel Marquez , Jaime Perea

Aims: Active Galactic Nuclei are known to be variable throughout the electromagnetic spectrum. An energy domain poorly studied in this respect is the hard X-ray range above 20 keV. Methods: The first 9 months of the Swift/BAT all-sky survey…

[abridged] We present an X-ray study of the low-luminosity active galactic nucleus (AGN) in NGC4258 using data from Suzaku, XMM-Newton, and the Swift/BAT survey. We find that signatures of X-ray reprocessing by cold gas are very weak in the…

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

Using self-consistent, physically motivated models, we investigate the X-ray obscuration in 19 Type 2 [OIII] 5007 \AA\ selected AGN, 9 of which are local Seyfert 2 galaxies and 10 of which are Type 2 quasar candidates. We derive reliable…

High Energy Astrophysical Phenomena · Physics 2015-06-19 Stephanie M. LaMassa , Tahir Yaqoob , Andrew F. Ptak , Jianjun Jia , Timothy M. Heckman , Poshak Gandhi , C. Meg Urry

Scanning and pointed RXTE observations of the nearby Seyfert 2 galaxy NGC 6300 reveal that it is a source of hard X-ray continuum and large equivalent width Fe K$\alpha$ emission. These properties are characteristic of Compton-reflection…

Astrophysics · Physics 2009-10-31 K. M. Leighly , J. P. Halpern , H. Awaki , M. Cappi , S. Ueno , J. Siebert

Mrk 590 is a Changing Look AGN currently in an unusual repeat X-ray and UV flaring state. Here, we report on deep X-ray observations with XMM-Newton, NuSTAR, and NICER, obtained at a range of X-ray flux levels. We detect a prominent soft…

Astrophysics of Galaxies · Physics 2025-03-18 Daniel Lawther , Marianne Vestergaard , Sandra Raimundo , Xiaohui Fan , Jun Yi Koay

Correlated variability between coronal X-rays and disc optical/UV photons provides a very useful diagnostic of the interplay between the different regions around an active galactic nucleus (AGN) and how they interact. AGN that reveal strong…

High Energy Astrophysical Phenomena · Physics 2023-12-13 Samuzal Barua , Oluwashina K. Adegoke , Ranjeev Misra , Pramod Pawar , V. Jithesh , Biman J. Medhi

We present the results of a 500 ksec long XMM-Newton observation and a 120 ksec long quasi-simultaneous Chandra observation of the Narrow Line Seyfert 1 galaxy 1H0707-495 performed in 2010 September. Consistent with earlier results by…

High Energy Astrophysical Phenomena · Physics 2015-06-03 T. Dauser , J. Svoboda , N. Schartel , J. Wilms , M. Dovciak , M. Ehle , V. Karas , M. Santos-Lleo , H. Marshall

We present a study of the complex absorbed X-ray spectrum of the Narrow Line Seyfert 1 galaxy NGC 7314. We collected available public X-ray data from the archives of XMM-Newton, Suzaku, and ASCA. The spectra were analyzed using the fitting…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 J. Ebrero , E. Costantini , J. S. Kaastra , B. De Marco , M. Dadina

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), and in particular, the reflection component, is shaped by the innermost and outer regions of the galactic nucleus. Our main goal is to investigate the variation of the Compton hump…

Astrophysics of Galaxies · Physics 2019-07-05 Christos Panagiotou , Roland Walter

We present the results of a joint {\it XMM-Newton} and {\it NuSTAR} campaign on the active galactic nucleus (AGN) IC 4329A, consisting of 9 $\times$ 20 ks {\it XMM-Newton} observations, and 5 $\times$ 20 ks {\it NuSTAR} observations within…

We analyze a 137 ks exposure X-ray spectrum of the Seyfert 1 galaxy NGC 5548 obtained with the XMM-Newton Reflection Grating Spectrometer. Due to the long exposure time, the spectrum is of higher statistical quality than the previous…

Astrophysics · Physics 2011-05-23 K. C. Steenbrugge , J. S. Kaastra , C. P. de Vries , R. Edelson

We present results from a half-day observation by XMM-Newton of the nucleus of the nearby Seyfert 2 galaxy NGC 6300. The X-ray spectrum of the nucleus consists of a heavily absorbed hard component dominating the 3--10 keV band and a soft…

ASCA observations of the Seyfert 2 galaxy NGC 7582 revealed it was highly variable on the timescale of $\sim2\times10^4$ s in the hard X-ray (2-10 keV) band, while the soft X-ray (0.5-2 keV) flux remained constant during the observations.…

Astrophysics · Physics 2015-06-24 S. -J. Xue , C. Otani , T. Mihara , M. Cappi , M. Matsuoka