The Ariel V sky survey of fast-transient X-ray sources.
Abstract
The Sky Survey Instrument (SSI) on Ariel V scanned the sky for 5.5 yr (about 30,000 orbits) in the energy band 2-18 keV, with a time resolution of one orbit (about 100 min). A systematic search has been made of the SSI database for fast-transient outbursts lasting one, or sometimes a few orbits. A discovery has been made of 27 fast-transient sources above the sensitivity limit of 8 SSI counts/sec, only two of which exhibited more than one outburst. It is estimated that an isotropic detector otherwise similar to the SSI would detect the start of one outburst every 3 days. The sources are isotropically distributed on the sky thereby favouring a nearby or extragalactic origin. Eleven of the sources are identified, including six with nearby RS CVn-like systems for which the observations favor a 'large loop' model. It is probable that many of the presently unidentified fast-transients also arise from nearby RS CVn (or related) systems although the observations do allow the possibility of outbursts from extragalactic objects out to a redshift of about 0.06.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- November 1983
- DOI:
- 10.1093/mnras/205.3.875
- Bibcode:
- 1983MNRAS.205..875P
- Keywords:
-
- Ariel 5 Satellite;
- Astronomical Catalogs;
- Bursts;
- Sky Surveys (Astronomy);
- Stellar Flares;
- X Ray Sources;
- Isotropy;
- Light Curve;
- Spatial Distribution;
- Variable Stars;
- Astronomy