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

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Results are presented for the first year of observations of a selected sample of Narrow-Line Seyfert 1 galaxies (Ton S 180, RE J1034+396, Ark 564) obtained with the imaging instruments onboard BeppoSAX. These are the first simultaneous…

Astrophysics · Physics 2015-06-24 A. Comastri , W. N. Brandt , K. M. Leighly , F. Fiore , M. Guainazzi , G. Matt , G. M. Stirpe

We present first INTEGRAL and XMM-Newton observations of a Seyfert galaxy, the type 2 AGN NGC 4388. Several INTEGRAL observations performed in 2003 allow us to study the spectrum in the 20 - 300 keV range. In addition two XMM-Newton…

In a ~ 20 ksec XMM-Newton observation the X-ray transient radio-quiet quasar PG 0844+349 was found in a historically high state compared to previous X-ray observations. The quasar showed a featureless spectrum with a strong soft excess over…

Astrophysics · Physics 2009-11-07 W. Brinkmann , D. Grupe , G. Branduardi-Raymont , E. Ferrero

In this paper we present the analysis of two broad band (0.1-150 keV) BeppoSAX observations of the Seyfert 1 galaxy NGC 3516. The two observations were taken 4 months apart, on 1996 November 8 and 1997 March 12 respectively. We report a…

We report the detection of the bright radio quiet quasar PG 1416-129 by the OSSE instrument on the Compton Gamma Ray Observatory (CGRO). This object had the hardest spectral index of all known AGN in the energy range 2-20 keV (Gamma=1.1 +-…

Astrophysics · Physics 2007-05-23 R. Staubert , M. Maisack

We present a multi-wavelength study of the radio-loud narrow line Seyfert 1 galaxy (NLSy1), 1H 0323+342, detected by Fermi Gamma Ray Space Telescope. Multi-band light curves show many orphan X-ray and optical flares having no corresponding…

High Energy Astrophysical Phenomena · Physics 2015-06-19 Vaidehi S. Paliya , S. Sahayanathan , M. L. Parker , A. C. Fabian , C. S. Stalin , Ayesha Anjum , S. B. Pandey

This paper presents ASCA (July 1997), XMM-Newton (December 2000) and BeppoSAX (January 2001) observations of the Piccinotti Seyfert 1 galaxy ESO198-G24. The BeppoSAX 0.1-200 keV spectrum exhibits reprocessing features, probably produced by…

Astrophysics · Physics 2009-11-07 M. Guainazzi

We report on the discovery of a narrow-emission-line object at z=0.672 detected in a deep ASCA survey. The object, AXJ0341.4-4453, has a flux in the 2--10keV band of 1.1+/-0.27 E-13 erg/s/cm**2, corresponding to a luminosity of 1.8E44 erg/s…

BeppoSAX and ASCA observations of the nearby (z=0.184), high-luminosity, radio-quiet quasar PDS456 are presented. The X-ray spectrum is characterized by a prominent ionized edge at 8-9 keV (originally discovered by RXTE, Reeves et al. 2000)…

Astrophysics · Physics 2007-05-23 C. Vignali , A. Comastri , F. Nicastro , G. Matt , F. Fiore , G. G. C. Palumbo

The observation of the Narrow-Line Seyfert 1 galaxy IRAS13349+2438 performed by XMM-Newton European Photon Imaging Camera between 0.3-10 keV, is presented here. The broadband spectrum of the source is dominated at low energies (E < 2 keV)…

Astrophysics · Physics 2009-11-10 A. L. Longinotti , M. Cappi , K. Nandra , M. Dadina , S. Pellegrini , ;

Results of the X-ray spectral analysis of the high-redshift radio-quiet quasar Q1101-264 are presented. The ASCA spectrum suggests a marginal evidence of a FeK$\alpha$ emission line at about 2 keV (observer's frame). Both the ASCA and ROSAT…

Astrophysics · Physics 2007-05-23 C. Vignali , A. Comastri , M. Cappi , G. G. C. Palumbo

We have examined the physical conditions within a bright emission-line knot in the inner narrow-line region (NLR) of the Seyfert 2 galaxy Mrk 573 using optical spectra and photoionization models. The spectra were obtained with the Hubble…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-11 S. B. Kraemer , M. L. Trippe , D. M. Crenshaw , M. Melendez , H. R. Schmitt , T. C. Fischer

We report on BeppoSAX broad band (0.1-100 keV) observations of bright Seyfert 2 galaxies and discuss the results in the framework of the unified theory of AGNs. The data are used to probe Nh distribution in type 2 objects and to identify…

Astrophysics · Physics 2007-05-23 L. Bassani , M. Cappi , G. Malaguti

We present XMM-Newton observations of three AGN taken as part of a hunt to find very heavily obscured Compton-thick AGN. For obscuring columns greater than 10^25 cm^-2, AGN are only visible at energies below 10 keV via reflected/scattered…

High Energy Astrophysical Phenomena · Physics 2015-05-28 M. L. Trippe , C. S. Reynolds , M. Koss , R. F. Mushotzky , L. M. Winter

We present Bepposax observations of the starburst/Seyfert composite galaxy Mrk609. This enigmatic object has an optical spectrum dominated by the features of starburst galaxies, yet its X-ray luminosity (6.3$\times10^{42}$\lunits) is…

Astrophysics · Physics 2016-08-30 A. Pappa , I. Georgantopoulos , M. Ward , A. L. Zezas

We selected a sample of eight bright unobscured (at least at the iron line energy) Seyfert Galaxies observed simultaneously by XMM-Newton and BeppoSAX, taking advantage of the complementary characteristics of the two missions. The main…

Astrophysics · Physics 2009-11-10 S. Bianchi , G. Matt , I. Balestra , M. Guainazzi , G. C. Perola

We report the first detection of a sharp spectral feature in a Narrow-Line Seyfert 1 galaxy. Using XMM-Newton we have observed 1H0707-495 and find a drop in flux by a factor of more than 2 at a rest-frame energy of ~7 keV without any…

We present a detailed analysis of the spectral properties of the Seyfert 1 galaxy 1H0419-577, based on the archival XMM-Newton, NuSTAR and simultaneous Swift observations taken between 2002-2015. All the observations show a broad emission…

High Energy Astrophysical Phenomena · Physics 2018-12-26 Jiachen Jiang , Dominic J. Walton , Andrew C. Fabian , Michael L. Parker

We present a detailed timing and spectral study of an extremely variable narrow-line Seyfert~1 galaxy NGC 4748 using observations in the year 2017 and 2014 performed with AstroSat and XMM-Newton, respectively. Both observations show…

High Energy Astrophysical Phenomena · Physics 2021-01-13 Main Pal , Neeraj Kumari , Pankaj Kushwaha , K. P. Singh , Alok C. Gupta , Sachindra Naik , G. C. Dewangan , P. Tripathi , Rathin Adhikari , O. Adegoke , H. Nandan

A detailed analysis of a long XMM-Newton observation of the Narrow Line Seyfert 1 galaxy 1H0707-495 is presented, including spectral fitting, spectral variability and timing studies. The two main features in the spectrum are the drop at ~ 7…

High Energy Astrophysical Phenomena · Physics 2015-05-14 A. Zoghbi , A. Fabian , P. Uttley , G. Miniutti , L. Gallo , C. Reynolds , J. Miller , G. Ponti