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Related papers: BeppoSAX Observations of 1-Jy BL Lacertae Objects …

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The BeppoSAX High Energy Large Area Survey (HELLAS) has surveyed several tens of square degrees of the sky in the 5--10 keV band down to a flux of about 5 10^-14 erg cm-2 s-1. The extrapolation of the HELLAS logN--logS towards fainter…

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

IC 4329A is the brightest known Seyfert galaxy in hard (~2-30 keV) X-rays and is likely to be representative of Seyfert 1 galaxies as a class. A recent 100 ks BeppoSAX observation (Perola et al. 1999) clearly confirmed the presence of a…

Astrophysics · Physics 2009-10-31 M. Cappi , G. Di Cocco , M. Dadina , G. Malaguti , M. Matsuoka , G. Matt , G. C. Perola , L. Piro

We address the question of why low-luminosity radio sources with similar flat radio spectra show a range of optical activity. The investigation is based on the spectral energy distributions (SEDs) of objects from the 200 mJy sample. We…

Astrophysics · Physics 2015-06-11 S. Anton , I. W. A. Browne , M. J. M. Marcha , M. Bondi , A. Polatidis

We study the time variability and spectral evolution of the Black Hole Candidate source XTE J1650-500 using the BeppoSax wide energy range (0.12-200 keV) observations performed during the 2001 X-ray outburst. The source evolves from a…

Astrophysics · Physics 2011-02-11 Enrico Montanari , Lev Titarchuk , Filippo Frontera

We present the first deep VLA radio images of flat-spectrum radio quasars (FSRQ) with multiwavelength emission properties similar to those of BL Lacs with synchrotron X-rays. Our observations of twenty-five of these sources show that their…

Astrophysics · Physics 2009-11-13 Hermine Landt , Eric S. Perlman , Paolo Padovani

We explain the properties of X-ray selected BL Lacertae objects, under the assumption that they constitute the small minority of the BL Lac population with energy cutoff located in the UV/X-ray band, as suggested by their multifrequency…

Astrophysics · Physics 2009-10-22 Paolo Padovani , Paolo Giommi

We present the 0.1-200 keV BeppoSAX spectrum of MR 2251-178 observed at two epochs in 1998 separated by 5 months. Both epochs show identical spectral shape and X-ray flux. Analysis of the combined spectra allow us to confirm the presence of…

Astrophysics · Physics 2009-11-06 A. Orr , P. Barr , M. Guainazzi , A. N. Parmar , A. J. Young , ;

We analyse a group of radio sources, a subset of the 200 mJy sample, all of which have core-jet radio structures measured with VLBI and have flat spectra stretching from the radio to the millimetre/sub-millimetre band. Thus the objects have…

Astrophysics · Physics 2009-11-10 S. Anton , I. W. A. Browne

Results of a 2000 August 12-13 BeppoSAX observation of the 7.1 hr eclipsing, dipping, bursting, transient, low-mass X-ray binary (LMXRB) X1658-298 are presented. The spectrum outside of eclipses, dips and bursts can be modeled by the…

Astrophysics · Physics 2009-11-06 T. Oosterbroek , A. N. Parmar , L. Sidoli , J. J. M. in 't Zand , J. Heise

We present the main results of broad band (0.1-10 keV) BeppoSAX observations of a selected sample of Narrow Line Seyfert 1 galaxies (NLS1s). We have performed a spectroscopic analysis of LECS and MECS data to test their average spectral…

Astrophysics · Physics 2007-05-23 F. Cancelliere , A. Comastri

Mkn 421 was repeatedly observed with BeppoSAX in 1997-1998. The source showed a very rich phenomenology, with remarkable spectral variability. This is the second of two papers presenting the results of a thorough temporal and spectral…

This work is a summary of the X-ray spectral studies of 29 TeV $\gamma$-ray emitting blazars observed with Swift/XRT, especially focusing on sources for which X-ray regime allows to study the low and the high energy ends of the particle…

High Energy Astrophysical Phenomena · Physics 2016-01-28 Alicja Wierzcholska , Stefan Wagner

We study a broad-band X-ray observation by BeppoSAX of the broad-line radio galaxy 3C 120. The primary X-ray continuum is well described by a power law with the photon index of Gamma=1.85+-0.05 and a high-energy break or a cutoff. The…

Astrophysics · Physics 2009-10-31 A. A. Zdziarski , P. Grandi

We present the analysis of archival data from ROSAT and ASCA of a serendipitous BL Lac object PKS 2316-423. Because of its featureless non-thermal radio/optical continuum, PKS 2316-423 has been called as a BL Lac candidate in the…

Astrophysics · Physics 2009-10-31 Sui-Jian Xue , You-Hong Zhang , Jian-Sheng Chen

We present first results of the BeppoSAX observation of the Coma Cluster. Thanks to the unprecedented sensitivity of the PDS instrument, the source has been detected up to ~80 keV. There is clear evidence for emission in excess to the…

Astrophysics · Physics 2007-05-23 R. Fusco-Femiano , D. Dal Fiume , L. Feretti , G. Giovannini , G. Matt , S. Molendi

We present the first results of BeppoSAX observations of a small sample of low brightness FRI radio galaxies. The flux of all the targets is consistent with a thermal spectrum, as due to the presence of hot intracluster gas or galactic…

Astrophysics · Physics 2015-06-24 E. Trussoni , F. Vagnetti , S. Massaglia , L. Feretti , P. Parma , R. Morganti , R. Fanti , P. Padovani , G. Bodo

We report the results of a new analysis of 13 wide band BeppoSAX observations of the BL Lac object Mkn 421. The data from LECS, MECS and PDS, covering an energy interval from 0.1 to over 100 keV, have been used to study the spectral…

Astrophysics · Physics 2009-11-10 E. Massaro , M. Perri , P. Giommi , R. Nesci

We present new optical and near-IR spectroscopy as well as new high dynamic range, arcsecond-resolution VLA radio maps of BL Lacs from the complete radio-selected "1 Jansky" (1Jy) sample (RBLs) for which such data were not previously…

Astrophysics · Physics 2009-11-06 Travis A. Rector , John T. Stocke

The recurrent hard pulsating X-ray transient \S was observed with \B on March 19, when the source was at a 2--10 keV flux level of $\sim$310~mCrab. We report on the high energy spectrum of the source, concentrating on cyclotron resonant…

The unification of X-ray and radio selected BL Lacs has been an outstanding problem in the blazar research in the past years. Recent investigations have shown that the gap between the two classes can be filled with intermediate objects and…

Astrophysics · Physics 2011-05-23 V. Beckmann , D. Engels , N. Bade , O. Wucknitz
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