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Related papers: 1H0419-577: a two-state Seyfert Galaxy?

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In this paper we report on the first simultaneous optical and X-ray (Beppo-SAX) observations of the radio-quiet AGN 1H0419-577. The optical spectrum clearly leads us to classify this source as a Seyfert 1. The X-ray spectrum is, however,…

Previous observations of the luminous Seyfert 1 galaxy 1H 0419-577 have found its X-ray spectrum to range from that of a typical Seyfert 1 with 2-10 keV power law index Gamma ~ 1.9 to a much flatter power law of Gamma ~ 1.5 or less. We…

Astrophysics · Physics 2009-11-10 K. A. Pounds , J. N. Reeves , K. L. Page , P. T. O'Brien

We present observations in the 0.1-100 keV spectral band of 8 Seyfert 2 galaxies, obtained by means of BeppoSAX. These sources were selected according to their [OIII] optical emission line flux, to avoid biases against obscuration on the pc…

Astrophysics · Physics 2007-05-23 R. Maiolino , M. Salvati , L. Bassani , M. Dadina , R. Della Ceca , G. Matt , G. Risaliti , G. Zamorani

We briefly review BeppoSAX observations of X-ray bright radio-galaxies. Their X-ray spectra are quite varied, and perhaps surprisingly, any similarity between radio-loud AGN and Seyfert galaxies is the exception rather than the rule. When…

Astrophysics · Physics 2009-10-31 Paola Grandi , C. Meg Urry , Laura Maraschi

An XMM-Newton observation of the luminous Seyfert 1 galaxy 1H 0419-577 is presented. We find that the spectrum is well fitted by a power law of canonical slope (gamma ~ 1.9) and 3 blackbody components (to model the strong soft excess). The…

Astrophysics · Physics 2009-11-07 K. L. Page , K. A. Pounds , J. N. Reeves , P. T. O'Brien

The BeppoSAX observations of the bright Narrow-Line Seyfert 1 galaxy Ark 564 are presented along with a high quality optical spectrum taken at the 1.5m telescope at La Silla. The 0.1-10 keV X-ray spectrum is characterized by a strong soft…

A systematic analysis of a large sample of radio-loud Active Galactic Nuclei available in the BeppoSAX public archive has been performed. The sample includes 3 Narrow Line Radio Galaxies (NLRG), 10 Broad Line Radio Galaxies (BLRG), 6 Steep…

Astrophysics · Physics 2009-11-13 Paola Grandi , Giuseppe Malaguti , Mariateresa Fiocchi , --

The Narrow Line Seyfert 1 galaxy Mrk 766 has been observed by BeppoSAX on May 1997. The source was fairly variable, both in flux and spectrum, during the observation. The variability is the largest around 2 keV, possibly due to variations…

Astrophysics · Physics 2016-08-30 Giorgio Matt , G. C. Perola , F. Fiore , M. Guainazzi , F. Nicastro , L. Piro

An XMM-Newton observation of the luminous Seyfert 1 galaxy 1H 0419-577 in September 2002, when the source was in an extreme low-flux state, found a very hard X-ray spectrum at 1-10 keV with a strong soft excess below ~1 keV. Comparison with…

Astrophysics · Physics 2009-11-10 K. A. Pounds , J. N. Reeves , K. L. Page , P. T. O'Brien

We report the transition to an active state of the nucleus in the Seyfert 1.9 galaxy NGC 2992, discovered by means of new hard X-ray data. While the 2-10 keV flux declined by a factor of ~ 20 from 1978 to 1994, two recent BeppoSAX…

Astrophysics · Physics 2007-05-23 R. Gilli , R. Maiolino , A. Marconi , G. Risaliti , M. Dadina , K. A. Weaver , E. J. M. Colbert

We present BeppoSAX observations of the Seyfert 1.8 galaxy NGC1365 in the 0.1--100 keV range. The source was 6 times brighter than during an ASCA observation 3 years earlier. The 4--10 keV flux is highly variable during the BeppoSAX…

Astrophysics · Physics 2007-05-23 G. Risaliti , R. Maiolino , L. Bassani

From the spectral analysis of a broadband (0.1-200 keV) BeppoSAX observation of the Seyfert 1 galaxy IC 4329A, the main results obtained are: a) the amount of reflection, together with the intensity of the iron K line, indicate a geometry…

Astrophysics · Physics 2007-05-23 G. C. Perola

We discuss the properties of the Seyfert 1.5 galaxy LB 1727, also known as 1H 0419-577, from X-ray observations obtained by ASCA and ROSAT along with optical observations from earlier epochs. ASCA shows only modest (< 20%) variations in…

We report on ROSAT and ASCA observations of the LINER NGC1052, which is the first one where broad optical lines in polarized light have been observed. The 2-10 keV spectrum is very flat, with an observed photon index (Gamma) ~0.1. A model…

Astrophysics · Physics 2009-10-31 M. Guainazzi , L. A. Antonelli

We have discovered a Narrow-Line Seyfert 1 (NLS1) galaxy and identified it with an ultrasoft X-ray source RX 215319-1514 detected with ROSAT. We present its X-ray and optical spectral characteristics. Its redshift is found to be…

Astrophysics · Physics 2007-05-23 K. P. Singh , L. R. Jones

We have used the BeppoSAX satellite to study the broad band (0.5-100 keV) X-ray spectrum of the Seyfert 1.5 galaxy MKN6. The source is characterized by a power law of Gamma=1.7 [+0.08, -0.07] and there is no strong evidence for either a…

Astrophysics · Physics 2009-09-17 A. Malizia , L. Bassani , M. Capalbi , A. C. Fabian , F. Fiore , F. Nicastro

We report optical, radio and X-ray observations of the Narrow-Line Seyfert 1 galaxy RX J1702.5+3247. The soft (0.1-2 keV) X-ray flux, measured by BeppoSAX, is characterized by strong variability on short time scales (< 500 sec). The most…

Astrophysics · Physics 2009-11-06 M. Gliozzi , W. Brinkmann , S. A. Laurent-Muehleisen , E. C. Moran , J. Whalen

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…

8.4-GHZ radio imaging study of an optically selected sample of early type Seyfert galaxies; comparison of images taken at two epochs reveals possible variation in the nuclear radio flux density in five of them over a seven year period. It…

Cosmology and Nongalactic Astrophysics · Physics 2011-07-25 C. G. Mundell , N. Nagar , P. Ferruit

We have studied the average 3-200 keV spectra of Seyfert galaxies of type 1 and 2, using data obtained with BeppoSAX. The average Seyfert 1 spectrum is well-fitted by a power law continuum with photon spectral index Gamma~1.9, a Compton…

Astrophysics · Physics 2009-11-07 A. Malizia , L. Bassani , J. B. Stephen , G. Di Cocco , F. Fiore , A. J. Dean
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