Influence of rotational broadening on the width of emission reversals of CA II and MG II resonant lines
Abstract
In spite of the low rotational velocities of late type stars, which usually lie below 15 km s-1, the rotational broadening of emission cores of Ca II and Mg II lines cannot always be disregarded. The most sensitive to rotational broadening are full widths at half-maximum and central absorption features such as K3. It is shown that the FWHM changes linearly with Vrot for low rotational velocities, and that rotational broadening can explain additional "intrinsic" broadening of the strongest emissions found in the Wilson-Bappu relation by Glebocki and Stawikowski. The authors also show that the convolution procedure used in rotational broadening calculations is not correct for chromospheric lines, and should be avoided, especially when K2 and K3 features are analyzed.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- December 1985
- Bibcode:
- 1985A&A...153..269B
- Keywords:
-
- Calcium;
- Magnesium;
- Resonance Lines;
- Spectral Line Width;
- Stellar Rotation;
- Stellar Spectra;
- Chromosphere;
- Emission Spectra;
- Metallicity;
- Stellar Atmospheres;
- Astrophysics