Observations of early-type stars at high galactic latitudes.
Abstract
Using equivalent widths and line profiles measured from high resolution AAT spectra in conjunction with model atmosphere calculations, it is shown that a sample of eleven high galactic latitude early-type stars are normal, distant objects. Stellar velocities in the z-direction determined from the spectra, coupled with the galactic gravitational field g(z), allow the times the stars would have taken to reach their present positions if they were ejected from the disc to be derived. A comparison of these times with the evolutionary ages indicate that at least four of the stars have been formed in situ, possibly from galactic fountain material.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- February 1986
- Bibcode:
- 1986A&A...155..333K
- Keywords:
-
- Early Stars;
- Galactic Evolution;
- Spectral Line Width;
- Stellar Composition;
- Stellar Spectra;
- Gravitational Fields;
- Radial Velocity;
- Stellar Atmospheres;
- Thermodynamic Equilibrium;
- Astrophysics