Absorption Line Profiles and Rotational Velocities for 59 Stars
Abstract
Absorption lines of He ii, He i, Mg ii, and other ions have been measured in coudé spectral tracings for 59 slowly and rapidly rotating sourthern O, B and A stars on the Main Sequence. All 668 separate line profiles have been analyzed with a procedure of differential corrections by least-squares to yield the following parameters and their error estimates: half-width, central depth, equivalent width, and shape parameter. The shape parameter includes Voigt profiles and also ‘super-Gaussian’ and ‘super-damping’ profiles. In addition, separately-measured line profiles in each star have been superimposed to yield better composite profiles with smaller errors. In addition, a preliminary value ofv sini is derived for each line by deconvolving it with both the intrinsic and instrumental profiles, and a mean value (including error bar) is derived for each star. The resulting mean values ofv sini are only about 2/3 as large as the earlier results presented by Buscombe (1969). The inadequacies of the traditional procedure are discussed, and plans for using calculated non-LTE intrinsic line profiles including line limb darkening and also effects of rotational distortion, will be outlined.
- Publication:
-
Astrophysics and Space Science
- Pub Date:
- October 1975
- DOI:
- 10.1007/BF00646073
- Bibcode:
- 1975Ap&SS..37..197B
- Keywords:
-
- Absorption Spectra;
- Angular Velocity;
- Line Spectra;
- Main Sequence Stars;
- Stellar Rotation;
- Stellar Spectra;
- A Stars;
- B Stars;
- Error Analysis;
- Helium Ions;
- Magnesium;
- O Stars;
- Astronomy