He I lambda 5876 as an indicator of activity in main-sequence stars.
Abstract
The absorption line He I λ5876 (D3) is observed in many main-sequence stars with spectral types as early as F0 and as late as K5. The equivalent width of D3 correlates well with the strength of the emission in Ca II H and K and with X-ray flux for late F-, G-, and K-type stars. In early F-type stars the strength of D3 shows no apparent correlation with rotational velocity, while a correlation does appear to be present in late F-type stars. This result is compatible with other data that suggest that stars with shallow convection zones differ significantly in terms of the nature of stellar activity from stars of later type with deeper convective zone.
- Publication:
-
Publications of the Astronomical Society of the Pacific
- Pub Date:
- August 1985
- DOI:
- 10.1086/131594
- Bibcode:
- 1985PASP...97..707W
- Keywords:
-
- Absorption Spectra;
- Helium Ions;
- Line Spectra;
- Main Sequence Stars;
- Stellar Activity;
- Stellar Spectra;
- Abundance;
- Deuterium;
- F Stars;
- G Stars;
- K Stars;
- Radial Velocity;
- Spectral Line Width;
- Stellar Atmospheres;
- Stellar Rotation;
- Stellar Spectrophotometry;
- Astrophysics