HD 93521: A High-Latitude Shell Star
Abstract
The evolutionary state of HD 93521 has been the subject of controversy. A review of the available evidence supports the conclusion that it is a main-sequence star. A principal argument for placing it in Population II rests on th erroneous application of the terminal velocity-escape velocity relation described by Abbot in 1978. H-alpha observations of HD 93521 show it to be a shell star. With the known flux variations of shell stars the use of this star as a UV flux standard should be reconsidered.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- February 1989
- DOI:
- 10.1086/185372
- Bibcode:
- 1989ApJ...337L..33I
- Keywords:
-
- Main Sequence Stars;
- Shell Stars;
- Stellar Evolution;
- Stellar Spectrophotometry;
- Emission Spectra;
- H Alpha Line;
- Stellar Luminosity;
- Stellar Rotation;
- Ultraviolet Radiation;
- Astrophysics;
- STARS: CIRCUMSTELLAR SHELLS;
- STARS: EARLY-TYPE;
- STARS: EMISSION-LINE;
- STARS: INDIVIDUAL HENRY DRAPER NUMBER: HD 93521