Detection of EUV emission from the low activity dwarf HD 4628: evidence for a cool corona.
Abstract
We present observations of low activity late-type stars obtained with the Extreme Ultraviolet Explorer (EUVE). These stars are the slowest rotators, and acoustic heating may dominate their outer atmospheric heating process. We report detection of EUV emission from the low activity K dwarf HD 4628 during the EUVE Deep Survey in the Lexan/boran band. This detection, in conjunction with the non-detection of this object in the ROSAT PSPC all-sky survey, suggests the existence of a cool corona with a characteristic temperature of less than 10^6^K. The flux and spectral signature are consistent with current theories of acoustic heating.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- November 1994
- Bibcode:
- 1994A&A...291..517M
- Keywords:
-
- Atmospheric Heating;
- Extreme Ultraviolet Radiation;
- Late Stars;
- Sky Surveys (Astronomy);
- Stellar Atmospheres;
- Stellar Convection;
- Stellar Temperature;
- Ultraviolet Emission;
- Extreme Ultraviolet Explorer Satellite;
- Stellar Coronas;
- Stellar Rotation;
- Astronomy;
- STARS: ACTIVITY;
- CORONAE;
- HD 4628;
- ULTRAVIOLET: STARS