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Related papers: 1H0419-577: A "two-state" soft X-ray Seyfert galax…

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The preliminary results of the BeppoSAX observation of the radio-quiet AGN 1H0419-577 are presented. Despite its broad line optical spectrum, the intermediate X-ray spectrum (i.e. 2--10 keV) is flatter than typically observed in Seyfert 1s…

Astrophysics · Physics 2015-06-24 M. Guainazzi , A. Comastri , G. Stirpe , W. N. Brandt , A. Parmar , E. M. Puchnarewicz

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

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 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…

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 present results of an infrared-to-X-ray study of 76 bright soft X-ray selected Seyfert galaxies discovered in the ROSAT All-Sky Survey. These objects are characterized by steep X-ray spectra in the 0.2-2.0 keV bandpass with power law…

Astrophysics · Physics 2007-05-23 D. Grupe , K. Beuermann , H. -C. Thomas , K. Mannheim , H. H. Fink

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

Two optical candidates - a galaxy and a star, are found within the error circle of the X-ray source position of an ultra-soft X-ray source discovered with ROSAT. Optical spectroscopy of the two candidates reveals that a) the galaxy is a…

Astrophysics · Physics 2007-05-23 Kulinder Pal Singh , Laurence R. Jones

We present detailed broadband UV/optical to X-ray spectral variability of the Seyfert 1 galaxy 1H 0419-577 using six XMM-Newton observations performed during 2002-2003. These observations covered a large amplitude variability event in which…

High Energy Astrophysical Phenomena · Physics 2018-01-08 Main Pal , Gulab C. Dewangan , Ajit K. Kembhavi , Ranjeev Misra , Sachindra Naik

We explore the origin of the strong soft X-ray excess in Narrow Line Seyfert 1 galaxies using spectral-timing information from a 120ks {\it XMM-Newton} observation of PG 1244+026. Spectral fitting alone cannot distinguish between a true…

High Energy Astrophysical Phenomena · Physics 2015-06-17 Chichuan Jin , Chris Done , Matthew Middleton , Martin Ward

We report on the first detection of hard X-ray photons (E>2.5 keV) in the X-ray transient Narrow-Line Seyfert 1 galaxy WPVS 007 which was the AGN with the softest X-ray spectrum during the ROSAT All-Sky Survey. The AGN is clearly detected…

Astrophysics · Physics 2009-11-13 Dirk Grupe , Karen M. Leighly , Stefanie Komossa

We present detailed broadband X-ray spectral variability of a Seyfert 1 galaxy 1H~0419--577 based on an archival \suzaku{} observation in July 2007, a new \suzaku{} observation performed in January 2010 and the two latest \xmm{}…

High Energy Astrophysical Phenomena · Physics 2015-06-16 Main Pal , Gulab C. Dewangan

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…

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 report the discovery and analysis of the follow-up ROSAT pointed observation, an ASCA observation and optical and radio observations of the enigmatic Narrow-Line Seyfert 1 galaxy RX J0134.2-4258. While its spectrum was one of the softest…

Astrophysics · Physics 2007-05-23 D. Grupe , K. M. Leighly , H. -C. Thomas , S. A. Laurent-Muehleisen

In this work we present the first of two papers devoted to the study of the X-ray spectral characteristics of Seyfert 1 galaxies in the Piccinotti sample. In particular we analyse here the BeppoSAX broad band (0.1-100 keV) data of 4 objects…

Astrophysics · Physics 2009-11-10 A. Quadrelli , A. Malizia , L. Bassani , G. Malaguti

Seyfert-type AGN that exhibit unusually strong and steep soft X-ray spectra are reviewed, building on observations made during the ROSAT all-sky survey. Two individual cases are described in brief detail, both being identified initially in…

Astrophysics · Physics 2007-05-23 K. A. Pounds , W. N. Brandt

We present preliminary results of the X-ray analysis of XMM-Newton and Swift observations as part of a multi-wavelength monitoring campaign in 2012 of the radio-loud narrow line Seyfert 1 galaxy PKS 2004-447. The source was recently…

High Energy Astrophysical Phenomena · Physics 2015-06-17 Annika Kreikenbohm , Matthias Kadler , Jörn Wilms , Robert Schulz , Cornelia Müller , Roopesh Ojha , Eduardo Ros , Karl Mannheim , Dominik Elsässer

We report the discovery and analysis of the follow-up ROSAT pointed observation, an ASCA observation and optical and radio observations of the enigmatic soft X-ray AGN RX J0134.2-4258. In the optical, RX J0134.2-4258 appears as an extreme…

Astrophysics · Physics 2007-05-23 D. Grupe , K. M. Leighly , H. -C. Thomas , S. A. Laurent-Muehleisen

Thirty years ago the optical counterpart of the x-ray source 1H0707-495 was discovered to be a 15th magnitude broad-line Seyfert galaxy with a rich Fe II emission line spectrum typical of the AGN subclass sometimes referred to as the I Zw 1…

Astrophysics of Galaxies · Physics 2017-08-08 Hartmut Winkler , Bynish Paul
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