Astronomy and Astrophysics – Astrophysics
Scientific paper
1995-12-04
Astronomy and Astrophysics
Astrophysics
18 pages gzipped and uuencoded postscript, including 10 figures accepted for publication in Astron. Astrophys
Scientific paper
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 the follow-up optical and radio observations which allow the identification of three of these objects as Narrow Line Seyfert 1 galaxies, and the fourth as BL Lac object. We have measured small-FWHM Hbeta lines, strong FeII emission and weak [OIII] emission in the three Narrow Line Seyfert 1 galaxies, in line with known correlations with respect to the steepness of the X-ray spectra. We have discovered strong optical variability in the BL Lac object and two of the Seyfert galaxies using photographic plates of the Sonneberg Observatory field patrol. We finally discuss the statistical implications of our search algorithm on the expected number density of soft X-ray selected AGN and conclude that up to 30% of X-ray selected AGN might have supersoft X-ray spectra.
Bade Norbert
Danner Rolf
Greiner Jochen
Komossa Stefanie
Kroll Peter
No associations
LandOfFree
Four new active galaxies with steep soft X-ray spectra does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Four new active galaxies with steep soft X-ray spectra, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Four new active galaxies with steep soft X-ray spectra will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-583405