Long-Period Oxygen-rich Optical Miras in the Solar Neighborhood
Abstract
The spatial distribution of the oxygen-rich Miras with periods longer than 400 days in the neighborhood of the sun were determined using available survey and the K-band period luminosity relationship. It is found that the exponential scale height of these stars is near 240 pc. There is a marked contrast between the Mira population at about 1 kpc from the Galactic center where there are nearly as many long-period oxygen-rich Miras as intermediate-period oxygen-rich Miras. It is hypothesized that, at about 1 kpc from the Galactic center, the main sequence stars with masses larger than 1 solar mass have higher metallicities than main-sequence stars with the same masses in the solar neighborhood. In the solar neighborhood such main sequence stars become carbon-rich on the AGB and in the region near the Galactic center they become long-period oxygen-rich Miras.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- August 1993
- DOI:
- 10.1086/172997
- Bibcode:
- 1993ApJ...413..298J
- Keywords:
-
- Infrared Stars;
- Oxygen;
- Solar Neighborhood;
- Stellar Mass Ejection;
- Variable Stars;
- Long Term Effects;
- Stellar Evolution;
- Astrophysics;
- GALAXY: STELLAR CONTENT;
- INFRARED: STARS;
- STARS: EVOLUTION;
- STARS: MASS LOSS;
- STARS: VARIABLES: OTHER LONG-PERIOD VARIABLES