Evidence for Nonpolar Emission in a New AM Herculis Candidate
Abstract
UBVRI and long-term plate photometry is presented of the faint and highly erratic cataclysmic variable discovered by Hawkins (1981, 1983) from a sequence of UK Schmidt measurements. Observations of the V roughly 18 star over two consecutive nights show pronounced and repeatable modulation at a binary period of 108.6 minutes. Dramatic color differences are evident in the folded UBVRI light curves which are strongly suggestive of cyclotron emission from two magnetic accretion funnels in an AM Herculis binary system. The binary period and the long time scale two-state activity of the source also support this classification. It is concluded that the object is almost certainly a new AM Herculis variable, and a model is developed in which the blue and red components originate from two nondiametric (and probably nonpolar) cyclotron regions that are characterized by differing electron temperatures and opacities.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- May 1988
- DOI:
- 10.1086/185160
- Bibcode:
- 1988ApJ...328L..59T
- Keywords:
-
- Binary Stars;
- Cataclysmic Variables;
- Stellar Radiation;
- Stellar Spectrophotometry;
- Astronomical Photometry;
- Magnetic Stars;
- White Dwarf Stars;
- Astrophysics;
- STARS: BINARIES;
- STARS: INDIVIDUAL CONSTELLATION NAME: GRUS V1;
- STARS: MAGNETIC;
- STARS: WHITE DWARFS