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Using the 3XMM catalogue of serendipitous X-ray sources, and the SDSS-DR9 spectroscopic catalogue, we have obtained a new sample of X-ray selected narrow emission line galaxies. The standard optical diagnostic diagram and selection by hard…

High Energy Astrophysical Phenomena · Physics 2014-09-05 Estelle Pons , Mike G. Watson

It has recently been suggested that Compton downscattering may give rise to the broad iron lines seen in the X-ray spectra of Seyfert 1 galaxies. This challenges the standard model in which these lines originate from the innermost regions…

Astrophysics · Physics 2009-10-31 C. S. Reynolds , J. Wilms

We present evidence that the outflowing UV absorbers in Seyfert 1 galaxies arise primarily in their inner narrow (emission) line regions (NLRs), based on similarities in their locations, kinematics, and physical conditions. 1) Hubble Space…

Astrophysics · Physics 2009-11-10 D. M. Crenshaw , S. B. Kraemer

We present Chandra X-ray observations of the nearby Seyfert 1.5 galaxy NGC 4151. The images show the extended soft X-ray emission on the several hundreds of pc scale with better sensitivity than previously obtained. The spectrum of the…

Astrophysics · Physics 2009-11-07 Y. Yang , A. S. Wilson , P. Ferruit

We investigate the X-ray spectrum of the Seyfert galaxy NGC 4151 using the simultaneous Suzaku/NuSTAR observation and flux-resolved INTEGRAL spectra supplemented by Suzaku and XMM observations. Our best spectral solution indicates that the…

High Energy Astrophysical Phenomena · Physics 2021-03-24 Michal Szanecki , Andrzej Niedzwiecki , Andrzej A. Zdziarski

An analysis of the X-ray variability of the low luminosity Seyfert nucleus NGC 4395, based on a long XMM-Newton observation, is presented. The power spectrum shows a clear break from a flat spectrum (alpha ~ 1) to a steeper spectrum (alpha…

Astrophysics · Physics 2009-09-17 S. Vaughan , K. Iwasawa , A. C. Fabian , K. Hayashida

We present results from the spectral analysis of a long XMM-Newton observation of the radio-loud NLS1 galaxy PKS0558-504. The source is highly variable, on all sampled time scales. We did not observe any absorption features in either the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 I. E. Papadakis , W. Brinkmann , M. Gliozzi , C. Raeth , F. Nicastro , M. L. Conciatore

We present a new X-ray analysis of the dwarf Seyfert galaxy NGC 4395, based on two archival XMM-Newton and Suzaku observations. This source is well known for a series of remarkable properties: one of the smallest estimated black hole masses…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Emanuele Nardini , Guido Risaliti

We report on observations of the iron K line in the nearby Seyfert 1 galaxy, NGC 3783, obtained in a long, 2 orbit (240 ks) XMM-Newton observation. The line profile obtained exhibits two strong narrow peaks at 6.4 keV and at 7.0 keV, with…

Astrophysics · Physics 2009-11-10 J. N Reeves , K. Nandra , I. M. George , K. A. Pounds , T. J. Turner , T. Yaqoob

We present a detailed analysis of a long, 100 ksec, observation of NGC 4151 by ASCA, contemporaneous with an observation by the CGRO/OSSE. We fit the data with physical models including an Fe K line and Compton reflection both…

We report on two Chandra observations, and a simultaneous Hubble Space Telescope ultraviolet observation, of the dwarf Seyfert 1 galaxy NGC 4395. Each Chandra observation had a duration of ~30 ks, with a separation of ~50 ks. The spectrum…

We present results obtained from the time-resolved X-ray spectral analysis of the Narrow-Line-Seyfert 1 galaxy SWIFT J2127.4+5654 during a ~130 ks XMM-Newton observation. We reveal large spectral variations, especially during the first ~90…

High Energy Astrophysical Phenomena · Physics 2015-06-17 Mario Sanfrutos , Giovanni Miniutti , Beatriz Agís-González , Andy C. Fabian , Jon M. Miller , Francesca Panessa , Abderahmen Zoghbi

We report on the first observation of the Seyfert 1 galaxy NGC4593 in the 0.1-200 keV band, performed with the BeppoSAX observatory. Its spectral components are for the first time simultaneously measured: a power-law with photon spectral…

Astrophysics · Physics 2007-05-23 M. Guainazzi , G. C. Perola , G. Matt , F. Nicastro , L. Bassani , F. Fiore , ; D. Dal Fiume , L. Piro

We detect seven distinct absorbing systems in the high-resolution X-ray spectrum of the Seyfert 1 galaxy IC 4329A, taken with XMM-Newton. Firstly we detect absorption due to cold gas in our own Galaxy and warm gas in the Galactic halo or…

In the past few years more and more pieces of evidence have been presented for a revision of the widely accepted Unified Model of Active Galactic Nuclei. A model based solely on orientation cannot explain all the observed phenomenology. In…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Andrea Marinucci , Stefano Bianchi , Fabrizio Nicastro , Giorgio Matt , Andy D. Goulding

Aims: We investigate the origin of X-rays and the nature of accretion flow in 4 LINERs hosted by radio galaxies, namely NGC1692, PKS0625-35, 3C88, 3C444, recently observed with XMM. Methods: We combine the results from the time-averaged…

Astrophysics · Physics 2009-11-13 M. Gliozzi , L. Foschini , R. M. Sambruna , F. Tavecchio

We report the discovery of strong soft X-ray emission lines and a hard continuum above 2 keV in the Narrow-Line Seyfert 1 galaxy Mrk 335 during an extremely low X-ray flux state. Mrk 335 was observed for 22 ks by XMM-Newton in July 2007 as…

XMM-Newton observations of the bright Seyfert 1.9 galaxy MCG-5-23-16 have revealed a broad FeKalpha emission line which is nearly symmetric in contrast to the broad and red-shifted asymmetric FeKalpha line sometimes observed from Seyfert 1…

Astrophysics · Physics 2009-11-07 G. C. Dewangan , R. E. Griffiths , N. J. Schurch

Preliminary results of the RXTE observation of the Seyfert 2 Galaxy NGC4507 are presented. The observed broadband [4-100 keV] spectrum is intrinsically hard (Gamma = 1.2); an iron line is detected with a relatively high equivalent width (EW…

Astrophysics · Physics 2007-05-23 M. Guainazzi , G. Matt , L. Piro , N. R. Robba

Context. Obscuration events caused by outflowing clumps or streams of high column density, low ionisation gas, heavily absorbing the X-ray continuum, have been witnessed in a number of Seyfert galaxies. Aims. We report on the X-ray…

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