A Giant X-ray/optical Flare on II Peg
Abstract
The paper presents a preliminary account of a large X-ray flare recorded by an X-ray satellite (it was also recorded in broadband optical light and in hydrogen Balmer emission) as a part of a campaign to monitor the RS CVn system II Peg with ground-based optical photometry and spectroscopy and satellite ultraviolet and X-ray spectroscopy. Two X-ray flares observed are described: the first one is relatively weak in X-rays, while the second flare which is the subject of the discussion, was present when the source was reacquired after earth occultation on August 17, 1989. Flare energy, temperature, and emission measure and volume are analyzed, and emphasis is placed on the observation of a line feature at approximately 6.8 keV, coinciding in energy to the position of the H-like FeXXVI line at 1.79 A.
- Publication:
-
Irish Astronomical Journal
- Pub Date:
- September 1990
- Bibcode:
- 1990IrAJ...19..150B
- Keywords:
-
- Cosmic X Rays;
- Light Emission;
- Stellar Flares;
- Stellar Spectra;
- Iron;
- Light Curve;
- Spaceborne Astronomy;
- X Ray Spectroscopy;
- Astrophysics