Astronomy and Astrophysics – Astrophysics
Scientific paper
1998-04-24
Astronomy and Astrophysics
Astrophysics
Accepted for publication in MNRAS, 10 pages
Scientific paper
10.1046/j.1365-8711.1998.01721.x
Steep soft X-ray (0.1-2 keV) quasars share several unusual properties: narrow Balmer lines, strong FeII emission, large and fast X-ray variability, rather steep 2-10 keV spectrum. These intriguing objects have been suggested to be the analogs of Galactic black hole candidates in the high, soft state. We present here results from ASCA observations for two of these quasars: NAB0205+024 and PG1244+026. Both objects show similar variations (factor of about 2 in 10 ks), despite a factor of about ten difference in the 0.5-10 keV luminosity (7.3E43 erg/s for PG1244+026 and 6.4E44 erg/s for NAB0205+024, assuming isotropic emission, H_0 = 50.0 and q_0 = 0.0). The X-ray continuum of the two quasars flattens by 0.5-1 going from the 0.1-2 keV band toward higher energies, strengthening recent results on another half dozen steep soft X-ray AGN. PG1244+026 shows a significant feature in the `1 keV' region, which can be described by either as a broad emission line centered at 0.95 keV (quasar frame) or as edge or line absorption at 1.17 (1.22) keV. The line emission could be due to reflection from an highly ionized accretion disk, in line with the view that steep soft X-ray quasars are emitting close to the Eddington luminosity. Photoelectric edge absorption or resonant line absorption could be produced by gas outflowing at a large velocity (0.3-0.6 c).
Cappi Massimo
Elvis Martin
Fiore Fabrizio
Leighly Karen M.
Matt Giorgia
No associations
LandOfFree
ASCA observations of two steep soft X-ray quasars 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 ASCA observations of two steep soft X-ray quasars, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and ASCA observations of two steep soft X-ray quasars will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-125841