IUE spectra of a flare in the RS Canum Venaticorum-type system UX Arietis.
Abstract
IUE spectra of UX Ari obtained during the large flare of 1979 January 1 exhibit chromospheric and transition-region emission-line fluxes about 2.5 and 5.5 times brighter than quiescent fluxes, respectively, and up to 1400 times brighter than the quiet sun. A high-dispersion spectrum of the 2000-3000 A region exhibits enhanced Fe II emission, which is probably associated mainly with the K0 IV star, and enhanced Mg II emission with asymmetric wings extending to +475 km/s. These line wings are interpreted as evidence for mass flow from the K0 IV star to the G5 V star. A speculative scenario of major long-lived RS CVn flares is proposed in which the component stars have very large corotating flux tubes, which occasionally interact. Magnetic reconnection results in flux tubes that temporarily connect the two stars.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- August 1980
- DOI:
- 10.1086/158178
- Bibcode:
- 1980ApJ...239..911S
- Keywords:
-
- Binary Stars;
- Flare Stars;
- Iue;
- Stellar Spectra;
- Ultraviolet Spectra;
- Emission Spectra;
- Line Spectra;
- Magnesium;
- Radiant Flux Density;
- Stellar Magnetic Fields;
- Astronomy