Gliese 841A : an EUV-selected chromospherically active binary system.
Abstract
We report the discovery of a new short-period, main sequence, chromospherically active late-type binary system. EUV observations performed by the ROSAT Wide Field Camera have identified the late-type star GL 841A as a possible very active star by virtue of a large EUV-to-bolometric flux ratio. Subsequent optical observations at the wavelengths of the H-alpha and Ca II H and K lines have confirmed this, and also the binary nature of the system. An orbital period of 1.124 d, an inclination of 28 deg and a mass ratio of approximately unity are deduced from radial velocity data. Both components show H-alpha in emission. The photometric colors and absolute magnitude indicate that the component stars are both spectral class dM3-5e. The GL 841A system is similar in many respects to the young eclipsing binary YY Gem.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- January 1993
- DOI:
- 10.1093/mnras/260.1.132
- Bibcode:
- 1993MNRAS.260..132J
- Keywords:
-
- Binary Stars;
- Chromosphere;
- Main Sequence Stars;
- Stellar Activity;
- White Dwarf Stars;
- Emission Spectra;
- Far Ultraviolet Radiation;
- H Alpha Line;
- Spectral Line Width;
- Stellar Atmospheres;
- Stellar Evolution;
- Stellar Spectra;
- Astrophysics