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A Multiwavelength Catalog of Seyfert 2 Galaxies Observed in the 2--10 keV Energy Band
Malaguti, G.; Bassani, L.; Polletta, M. +2 more
This paper is a catalog of Seyfert 2 galaxies observed in the 2-10 keV band (339 flux entries). In total, it contains data on 150 objects; for 76 objects, a positive detection is reported, while for the remaining sources, 2 σ upper limits to the X-ray emission are given. Most of the data have been collected from the literature over a period starti…
Multifrequency Spectra of EXOSAT Blazars
Ghosh, K. K.; Soundararajaperumal, S.
Blazars have been divided into two groups: radio-selected blazars (RBLs) and X-ray-selected blazars (XBLs). Results of the X-ray spectral analysis of 28 such blazars which were observed with EXOSAT are presented in this paper, and in four these are new results which were not published earlier. X-ray results suggest that XBLs are steep-spectrum sou…
The X-Ray Spectra of Blazars: Analysis of the Complete EXOSAT Archive: Erratum
Giommi, Paolo; Barr, Paul; Sambruna, Rita M. +3 more
In the paper "The X-Ray Spectra of Blazars: Analysis of the Complete EXOSAT Archive" by Rita M. Sambruna, Paul Barr, Paolo Giommi, Laura Maraschi, Gianpiero Tagliaferri, and Aldo Treves (ApJS, 95,371 [1994]), the section regarding the object PKS 1510-08 (Section 4.4.14) contains an erroneous quotation. K. P. Singh, A.R. Rao, and M.N. Vahia (ApJ, 3…
The X-Ray Spectra of Blazars: Analysis of the Complete EXOSAT Archive
Giommi, Paolo; Barr, Paul; Sambruna, Rita M. +3 more
We analyzed the 0.1-10 keV spectra of 26 blazars (21 BL Lac objects and 5 highly polarized quasars), on the basis of 93 exposures taken from the EXOSAT archives. Fits were performed first with a single power-law model. Indications are found that better fits can be obtained with models where the slope steepens at higher energies. We therefore consi…
High-Energy Spectra of Active Galactic Nuclei. I. The Catalog
Malaguti, G.; Bassani, L.; Caroli, E.
This paper presents a catalog of high-energy spectra (E >= 0.01 keV) of active galactic nuclei (AGNs). The catalog contains 209 objects (140 Seyfert galaxies, 65 quasars, and 4 objects otherwise classified), for a total of 1030 spectra. Most of the data have been collected from the literature over a period spanning more than 20 yr starting from…
A Catalog of X-Ray Spectra of BL Lacertae Objects
Bassani, L.; Ciliegi, P.; Caroli, E.
This paper contains a list of X-ray spectra of BL Lac objects mostly collected from the literature. For a small sample of objects EXOSAT/ME spectra have also been analyzed and included in this list. In the catalog 42 objects are considered (26 radio selected and 16 X-ray selected) for a total of 311 X-ray spectra. For each object we report the X-r…
The Extreme Ultraviolet Spectrograph: A Radial Groove Grating, Sounding Rocket--borne, Astronomical Instrument
Wilkinson, Erik; Green, James C.; Cash, Webster
The design, calibration, and sounding rocket flight performance of a novel spectrograph suitable for moderate-resolution EUV spectroscopy are presented. The sounding rocket-borne instrument uses a radial groove grating to maintain a high system efficiency while controlling the aberrations induced when doing spectroscopy in a converging beam. The i…
X-Ray Luminosity and Spectral Variability of Hard X-Ray--selected Active Galactic Nuclei
Tagliaferri, G.; Giommi, P.; Grandi, P. +2 more
One hundred sixty-one observations archived in the EXOSAT data base are analyzed in order to study time and spectral variability of all 30 sion-line active galactic nuclei (AGNs) in the Piccinotti sample. For each source long-term (from days to months) and short-term (from minutes to hours) luminosity variations were sought using the soft (LE: 0.0…