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Related papers: X-rays from Radio-Galaxies: BeppoSAX Observations

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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 investigate the 1.4 GHz radio properties of 92 nearby (z<0.05) ultra hard X-ray selected Active Galactic Nuclei (AGN) from the Swift Burst Alert Telescope (BAT) sample. Through the ultra hard X-ray selection we minimise the biases…

Astrophysics of Galaxies · Physics 2016-05-04 O. Ivy Wong , M. J. Koss , K. Schawinski , A. D. Kapińska , I. Lamperti , K. Oh , C. Ricci , S. Berney

The supermassive black holes in active galactic nuclei (AGN) and stellar-mass black holes in X-ray binaries (XRBs) are believed to work in a similar way. While XRBs evolve rapidly and several sources have undergone a few complete cycles…

Astrophysics of Galaxies · Physics 2017-07-26 Jiri Svoboda , Matteo Guainazzi , Andrea Merloni

We report on highlight results on celestial sources observed in the high energy band (>20 keV) with BeppoSAX. In particular we review the spectral properties of sources that belong to different classes of objects, i.e. stellar coronae…

We observed the nearby galaxy M~51 (NGC 5194) with BeppoSAX. The X-ray properties of the nucleus below 10 keV are almost the same as the ASCA results regarding the hard component and the neutral Fe K$\alpha$ line, but the intensity is about…

Astrophysics · Physics 2009-11-06 Yasushi Fukazawa , Naoko Iyomoto , Aya Kubota , Yukari Matsumoto , Kazuo Makishima

X-ray spectral features which are unusually strong in many Narrow-Line Seyfert galaxies are found to be consistent with reflection from strongly ionized matter, providing further evidence of a high accretion rate in these objects and…

Astrophysics · Physics 2009-10-31 K. Pounds , S. Vaughan

Study of high-redshift radio galaxies (HzRGs) can shed light on the active galactic nuclei (AGNs) evolution in massive elliptical galaxies. The vast majority of observed high-redshift AGNs are quasars, and there are very few radio galaxies…

I present a study of the X-ray spectral properties of a sample containing 24 type-1 active galactic nuclei using the medium spectral resolution of ``ASCA''. The sample consists of 20 radio-quiet objects and 4 radio-loud objects. A simple…

Astrophysics · Physics 2015-06-24 C. S. Reynolds

We present X-ray results on the ultraluminous infrared galaxy Arp220 obtained with BeppoSAX. The X-ray emission up to 10 keV is detected. No significant signal is detected with the PDS detector in the higher energy band. The 2-10 keV…

Astrophysics · Physics 2009-09-17 K. Iwasawa , G. Matt , M. Guainazzi , A. C. Fabian

We analyze the optical spectra of massive (log M*/Msun > 11.4) radio-loud galaxies at z~0.2 and z~0.6. By comparing stellar population parameters of these radio-loud samples with radio-quiet control samples, we investigate how the presence…

Hard X-ray selection is the most efficient way to discriminate between accretion-powered sources, such as AGN, from sources dominated by starlight. Hard X-rays are also less affected than other bands by obscuration. We have then carried out…

Astrophysics · Physics 2009-10-31 F. Fiore , F. La Franca , P. Giommi , M. Elvis , G. Matt , A. Comastri , S. Molendi , I. Gioia

We present a comprehensive study of the soft X-ray properties of the BeppoSAX High-Energy Large Area Survey (HELLAS) sources. A large fraction (about 2/3) of the hard X-ray selected sources is detected by ROSAT. The soft X-ray colors for…

Astrophysics · Physics 2009-11-06 C. Vignali , A. Comastri , F. Fiore , F. La Franca

Analysis of the frequency and physical properties of galaxies with star-formation and AGN activity in different environments in the local universe is a cornerstone for understanding structure formation and galaxy evolution. We have built a…

Astrophysics · Physics 2008-11-26 Pietro Reviglio , David J. Helfand

Over the last few years several models have been proposed to interpret the widespread soft excess observed in the X-ray spectra of type 1 active galactic nuclei (AGN). In particular, reflection from the photoionized accretion disc blurred…

High Energy Astrophysical Phenomena · Physics 2015-05-19 E. Nardini , A. C. Fabian , R. C. Reis , D. J. Walton

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…

[abridged] We present an X-ray study of the low-luminosity active galactic nucleus (AGN) in NGC4258 using data from Suzaku, XMM-Newton, and the Swift/BAT survey. We find that signatures of X-ray reprocessing by cold gas are very weak in the…

X-ray binaries are known to show state transitions related to accretion rate changes which are often accompanied with dramatic changes in the jet emission. However, it is not clear whether this characteristics of stellar-mass black hole…

Astrophysics of Galaxies · Physics 2023-04-21 K. É. Gabányi , K. Smith , S. Frey , Z. Paragi , T. An , A. Moór

A review of recent developments in the field of X-ray surveys, especially in the hard (2-10 and 5-10 keV) bands, is given. A new detailed comparison between the measurements in the hard band and extrapolations from ROSAT counts, that takes…

Astrophysics · Physics 2007-05-23 P. Giommi , F. Fiore , M. Perri

We present the results from a study of the X-ray variability and the near-IR to X-ray spectral energy distribution of four low-luminosity, Seyfert 1 galaxies. We compared their variability amplitude and broad band spectrum with those of…

Astrophysics · Physics 2009-11-13 I. E. Papadakis , Z. Ioannou , W. Brinkmann , E. M. Xilouris

We present the analysis of 31 observations of 20 bright Compton thin Seyfert 2s, in the 0.1-200 keV band, performed with the BeppoSAX satellite. The sample consists of all Seyfert 2s in the BeppoSAX public archive, with a 2-10 keV flux…

Astrophysics · Physics 2009-11-07 G. Risaliti
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