Searching for the metal-weak thick disc in the solar neighbourhood
Abstract
An abundance analysis is presented of 60 metal-poor stars drawn from catalogues of nearby stars provided by Arifyanto et al. and Schuster et al. In an attempt to isolate a sample of metal-weak thick disc stars, we applied the kinematic criteria Vrot >= 100kms-1,|ULSR| <= 140kms-1 (LSR - local standard of rest) and |WLSR| <= 100kms-1. 14 stars satisfying these criteria and having [Fe/H] <= -1.0 are included in the sample of 60 stars. Eight of the 14 have [Fe/H] >= -1.3 and may be simply thick disc stars of slightly lower than average [Fe/H]. The other six have [Fe/H] from -1.3 to -2.3 and are either metal-weak thick disc stars or halo stars with kinematics mimicking those of the thick disc. The sample of 60 stars is completed by eight thick disc stars, 20 stars of a hybrid nature (halo or thick disc stars) and 18 stars with kinematics distinctive of the halo.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- November 2008
- DOI:
- 10.1111/j.1365-2966.2008.13905.x
- arXiv:
- arXiv:0809.0966
- Bibcode:
- 2008MNRAS.391...95R
- Keywords:
-
- stars: abundances;
- stars: atmospheres;
- stars: kinematics;
- Galaxy: abundances;
- Galaxy: evolution;
- Astrophysics
- E-Print:
- 18 pages including 13 figures and 7 tables