A Spectroscopic Study of the Ancient Milky Way: F‐ and G‐Type Stars in the Third Data Release of the Sloan Digital Sky Survey
2006; IOP Publishing; Volume: 636; Issue: 2 Linguagem: Inglês
10.1086/498131
ISSN1538-4357
AutoresCarlos Allende Prieto, Timothy C. Beers, Ronald Wilhelm, Heidi Jo Newberg, Constance M. Rockosi, B. Yanny, Young Sun Lee,
Tópico(s)Astrophysics and Star Formation Studies
Resumo(Abridged) We perform an analysis of spectra and photometry for 22,770 stars included in the third data release (DR3) of the SDSS. We measure radial velocities and, based on a model-atmosphere analysis, derive estimates ofthe atmospheric parameters (effective temperature, surface gravity, and [Fe/H]) for each star. Stellar evolution models are then used to estimate distances. The SDSS sample covers a range in stellar brightness of 14 < V < 22, and comprises large numbers of F- and G-type stars from the thick-disk and halo populations (up to 100 kpc from the galactic plane), therefore including some of the oldest stars in the Milky Way. In agreement with previous results from the literature, we find that halo stars exhibit a broad range of iron abundances, with a peak at [Fe/H] ~ -1.4. This population exhibits essentially no galactic rotation. Thick-disk G-dwarf stars at distances from the galactic plane in the range 1
Referência(s)