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

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We have discovered four AGN in the ROSAT all-sky-survey data with very steep X-ray spectra. We apply several models to these X-ray spectra with emphasis on warm absorber models which give an adequate description of the data. We report on…

Astrophysics · Physics 2007-05-23 J. Greiner , R. Danner , N. Bade , G. A. Richter , P. Kroll , S. Komossa

We have observed a radio-quiet QSO Kaz 102 (z=0.136) with ASCA as a part of our program of complete spectral characterization of hard X-ray selected AGNs. We found that Kaz 102 shows unusual spectral properties. A simple power-law with…

We present an analysis of spectrum and variability of the bright reddened narrow line Seyfert 1 galaxy Was~61 using 90 ks archival {\it XMM-Newton} data. The X-ray spectrum in 0.2-10 keV can be characterized by an absorbed power-law plus…

High Energy Astrophysical Phenomena · Physics 2016-03-11 Liming Dou , Ting-Gui Wang , Yanli Ai , Weimin Yuan , Hongyan Zhou , Xiao-Bo Dong

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

In this paper we discuss the X-ray properties of 49 local (z<0.035) Seyfert 2 galaxies with HST/WFC2 high-resolution optical coverage. It includes the results of 26 still unpublished Chandra and XMM-Newton observations, which yield 25 (22)…

Astrophysics · Physics 2009-11-11 M. Guainazzi , G. Matt , G. C. Perola

We present the results of the analysis of an archival 15 ks XMM-Newton observation of the nearby (z=0.057) radio-loud source 3C445, optically classified as a Broad-Line Radio Galaxy. While the RGS data are of insufficient quality to allow a…

Astrophysics · Physics 2009-06-23 R. M. Sambruna , J. N. Reeves , V. Braito

We present preliminary results of the analysis of optical spectra of two complementary samples of Seyfert galaxies. The first sample was extracted from a selection of the 4th Fermi Gamma-ray Large Area Telescope (4FGL) catalog, and consists…

Astrophysics of Galaxies · Physics 2023-11-06 Benedetta Dalla Barba , Marco Berton , Luigi Foschini , Giovanni La Mura , Amelia Vietri , Stefano Ciroi

X-ray variability is very common in active galactic nuclei (AGN), but these variations may not occur similarly in different families of AGN. We aim to disentangle the structure of low ionization nuclear emission line regions (LINERs)…

Astrophysics of Galaxies · Physics 2016-06-15 Lorena Hernandez-Garcia , Josefa Masegosa , Omaira Gonzalez-Martin , Isabel Marquez , Jaime Perea

We use the data from a recent, 100 ksec XMM-Newton observation of the Narrow Line Seyfert 1 galaxy Ark 564 to obtain its time average, X-ray spectrum. The 3-11 keV spectrum is well fitted by a power-law of slope 2.43. We detect a weak…

Astrophysics · Physics 2009-11-11 I. E. Papadakis , W. Brinkmann , M. J. Page , I. McHardy , P. Uttley

The AGN NGC 2110 presents a peculiar case among the Seyfert 2 galaxies, as it displays also features of radio-loud objects and is classified as FR-I radio galaxy. Here we analyse simultaneous INTEGRAL and Swift data taken in 2008 and 2009.…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-28 Volker Beckmann , Olivier Do Cao

We report the discovery of a highly X-ray variable AGN, RX J2217.9-5941. This object was bright during the ROSAT All-Sky Survey (RASS), during which a decrease in the count rate by a factor of 12 was observed. It was found to be much…

Astrophysics · Physics 2009-11-06 D. Grupe , H. -C. Thomas , K. M. Leighly

We present 8.4 GHz VLA A-configuration observations of 87 sources from the mid-infrared-selected AGN sample of Rush et al (1993). These 0.25 arcsec resolution observations allow elongated radio structures tens of parsecs in size to be…

Astrophysics · Physics 2009-10-31 Andy Thean , Alan Pedlar , Marek J. Kukula , Stefi A. Baum , Christopher P. O'Dea

We present an analysis of five Suzaku observations of the bright Seyfert1 galaxy IC 4329A. The broad energy band and high signal-to-noise ratio of the data give new constraints on the iron K alpha line profile and its relationship with the…

High Energy Astrophysical Phenomena · Physics 2015-06-19 Giulia Mantovani , Kirpal Nandra , Gabriele Ponti

We report on a long X-ray observation of the slow-rotating binary pulsar GX 1+4. BeppoSAX observed, in the 0.1-200 keV energy range, an event in which the source flux dropped for almost a day, and then recovered. During this event only the…

Within the context of investigating possible differences between the mechanisms at play in Radio Loud AGN and those in Radio Quiet ones, we study the spectral characteristics of a selected sample of Intermediate-Luminosity Broad-Line Radio…

Astrophysics · Physics 2008-07-28 E. Angelakis , M. Kadler , K. Lewis , R. M. Sambruna , M. Eracleous , J. A. Zensus

We report the BeppoSAX observations of 6 Flat Spectrum Radio Quasars. Three of them have a clear detection up to 100 keV with the PDS instrument. For 4 objects the X-ray spectrum is satisfactorily fitted by a power-law continuum with…

We present a X-ray spectroscopic study of the bright Compton-thick Seyfert 2s NGC1068 and the Circinus Galaxy, performed with BeppoSAX. Matt et al. (1997 and 1998) interpreted the spectrum above 4 keV as the superposition of Compton…

We present the results from a long term X-ray analysis of Mrk 279 during the period 2018-2020. We use data from multiple missions - AstroSat, NuSTAR and XMM-Newton, for the purpose. The X-ray spectrum can be modelled as a double…

High Energy Astrophysical Phenomena · Physics 2024-05-15 K. Akhila , Ranjeev Misra , Savithri H. Ezhikode , K. Jeena

We present the results of an extensive analysis of the ``ASCA'' AO2 observation of the Seyfert 1 galaxy NGC4051. The target exhibits broadband [0.5--10 keV] variability by a factor $\sim 8$ on time scales $\sim 10^4 s$, with a typical…

Astrophysics · Physics 2015-06-24 Matteo Guainazzi , Tatehiro Mihara , Chiko Otani , Masaru Matsuoka

We present a systematic analysis of all the BeppoSAX data of the soft gamma-ray repeater SGR 1900+14: these observations allowed us to study the long term properties of the source quiescent emission. In the observation carried out before…

Astrophysics · Physics 2009-02-26 P. Esposito , S. Mereghetti , A. Tiengo , L. Sidoli , M. Feroci , P. Woods
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