Discovery of soft X-ray oscillations in VW Hydri.
Abstract
In this paper, the discovery of short-period oscillations in the soft X-ray flux, emitted by the dwarf nova VW Hydri during superoutburst, is reported. A modulation of 15 percent, with a period of 14.06 + or - 0.02 s, was detected near the end of the November 1983 superoutburst. The oscillation was observed for two hours, and is coherent to within the limits of observation. A less coherent oscillation was detected near the maximum of the October, 1984 superoutburst. This oscillation shows erratic period changes between 14.2 and 14.4 s. The pulsed emission probably has a harder spectrum than the nonpulsed emission. Upper limits to the amplitude of oscillations during other observations of VW Hydri during normal outburst, superoutburst and quiescence indicate that these 14 s oscillations are a transient effect. The properties, and origin of the soft X-ray oscillations in dwarf novae are discussed.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- August 1987
- Bibcode:
- 1987A&A...182..219V
- Keywords:
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- Cataclysmic Variables;
- Dwarf Novae;
- Stellar Oscillations;
- X Ray Stars;
- Binary Stars;
- Periodic Variations;
- White Dwarf Stars;
- Astrophysics