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To understand the nature of transient obscuring outflows in active galactic nuclei, we observed the Seyfert 1 galaxy NGC 3783 on two occasions in December 2016 triggered by Swift monitoring indicating strong soft X-ray absorption in…

We present a Suzaku observation of the dwarf Seyfert galaxy NGC4395 with an estimated black hole mass of ~10^5 Msun. Rapid and strong X-ray variability with an rms amplitude of ~60 per cent is observed in the 0.4-10 keV band with the XIS…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-02 K. Iwasawa , Y. Tanaka , L. C. Gallo

The Seyfert 2 galaxy NGC 7674 has been observed within the BeppoSAX Core Programme with the onboard narrow field instruments between 0.1 and 100 keV. The broad-band spectrum shows four most relevant spectral components: a) a soft excess…

The first X-ray observation of the Seyfert 2 galaxy NGC5252 is reported. ASCA collected $\sim 4000$ photons/detector enough to perform an accurate spectral analysis of this source. The luminosity of NGC5252 is L$_{\rm X}$(0.7-10 keV)…

Astrophysics · Physics 2009-10-28 M. cappi , T. Mihara , M. Matsuoka , W. Brinkmann , M. A. Prieto , G. G. C. Palumbo

IRAS 00521$-$7054 is the first Seyfert 2 in which the presence of an extremely large Fe K$\alpha$ line has been claimed. We report here on the analysis of a 100 ks Suzaku observation of the source. We confirm the existence of a very strong…

High Energy Astrophysical Phenomena · Physics 2015-06-22 Claudio Ricci , Fumie Tazaki , Yoshihiro Ueda , Stephane Paltani , Rozenn Boissay , Yuichi Terashima

We consider new Suzaku data for NGC 3516 taken during 2009, along with other recent X-ray observations of the source. The cumulative characteristics of NGC 3516 cannot be explained without invoking changes in the line-of-sight absorption.…

High Energy Astrophysical Phenomena · Physics 2015-05-27 T. J. Turner , L. Miller , S. B. Kraemer , J. N. Reeves

In the present work we report the BeppoSAX serendipitous discovery of the type 2 AGN 1SAXJ2234.8-2541 in the MECS field of view when pointing at the Seyfert 2 galaxy NGC7314. The source is optical identified with the bright (m_B=14.40)…

Astrophysics · Physics 2007-05-23 A. Malizia , L. Bassani , I. Negueruela

We present BeppoSAX observations of 6 ``type-2'' LINER and ``transition'' galaxies (NGC3379, NGC3627, NGC4125, NGC4374, NGC5195 and NGC5879)from the Ho et al. (1997) spectroscopic sample of nearby galaxies. All objects are detected in the…

Astrophysics · Physics 2016-08-30 I. Georgantopoulos , F. Panessa , A. Akylas , A. Zezas , M. Cappi , A. Comastri

The Unification Model for active galactic nuclei posits that Seyfert 2s are intrinsically like Seyfert 1s, but that their broad-line regions (BLRs) are hidden from our view. A Seyfert 2 nucleus that truly lacked a BLR, instead of simply…

Astrophysics · Physics 2008-11-26 Himel Ghosh , Richard W. Pogge , Smita Mathur , Paul Martini , Joseph C. Shields

We present the results of a Suzaku monitoring campaign of the Seyfert 2 galaxy, NGC7582. The source is characterized by very rapid (on timescales even lower than a day) changes of the column density of an inner absorber, together with the…

Astrophysics of Galaxies · Physics 2011-02-11 Stefano Bianchi , Enrico Piconcelli , Marco Chiaberge , Elena Jimenez Bailon , Giorgio Matt , Fabrizio Fiore

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

We present spectral analysis of two Suzaku observations of the Seyfert 2 galaxy, NGC 2110. This source has been known to show complex, variable absorption which we study in depth by analyzing these two observations set seven years apart and…

This paper reports the discovery of a bright X-ray transient source, Suzaku J1305-4913, in the south-west arm of the nearby Seyfert II galaxy NGC 4945. It was detected at a 0.5 -- 10 keV flux of $2.2 \times 10^{-12}$ erg cm$^{-2}$ s$^{-1}$…

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

In this paper, a BeppoSAX observation of the bright Seyfert 2 galaxy NGC6300 is presented. The rapidly variable emission from the active nucleus is seen through a Compton-thin (NH ~ 3x10^23 atomoms/cm/cm) absorber. A Compton-reflection…

Astrophysics · Physics 2009-11-07 M. Guainazzi

We use the full broad-band XMM-Newton EPIC data to examine the X-ray spectrum of the nearby Seyfert 2 galaxy NGC 1068, previously shown to be complex with the X-ray continuum being a sum of components reflected/scattered from cold (neutral)…

Astrophysics · Physics 2009-11-11 K. Pounds , S. Vaughan

We present results from an XMM-Newton observation of the nearby Seyfert 2 galaxy NGC5643. The nucleus exhibits a very flat X-ray continuum above 2 keV, together with a prominent K-alpha fluorescent iron line. This indicates heavy…

Astrophysics · Physics 2009-11-10 M. Guainazzi , P. Rodriguez-Pascual , A. C. Fabian , K. Iwasawa , G. Matt

We report on the deepest X-ray observation of the narrow-line Seyfert 1 galaxy Mrk 335 in the low-flux state obtained with Suzaku. The data are compared to a 2006 high-flux Suzaku observation when the source was ~10-times brighter.…

High Energy Astrophysical Phenomena · Physics 2015-06-23 L. C. Gallo , D. R. Wilkins , K. Bonson , C-Y. Chiang , D. Grupe , M. L. Parker , A. Zoghbi , A. C. Fabian , S. Komossa , A. L. Longinotti

We present results from a 150 ksec Suzaku observation of the Seyfert 1.5 NGC 3516 in October 2005. The source was in a relatively highly absorbed state. Our best-fit model is consistent with the presence of a low-ionization absorber which…

We present the first results of the Chandra and optical follow-up observations of hard X-ray sources detected in the ASCA Medium Sensitivity Survey (AMSS). Optical identifications are made for five objects. Three of them show either weak or…