Oxygen in the Galactic thin and thick disks
Abstract
First results from a study into the abundance trends of oxygen in the Galactic thin and thick disks are presented. Oxygen abundances for 21 thick disk and 42 thin disk F and G dwarf stars based on very high resolution spectra (R\sim 215000) and high signal-to-noise (S/N>400) of the faint forbidden oxygen line at 6300 A have been determined. We find that [O/Fe] for the thick disk stars show a turn-down, i.e. the ``knee'', at [Fe/H] between -0.4 and -0.3 dex indicating the onset of SNe type Ia. The thin disk stars on the other hand show a shallow decrease going from [Fe/H] \sim -0.7 to the highest metallicities with no apparent ``knee'' present indicating a slower star formation history.
Cite
@article{arxiv.astro-ph/0212029,
title = {Oxygen in the Galactic thin and thick disks},
author = {T. Bensby and S. Feltzing and I. Lundstrom},
journal= {arXiv preprint arXiv:astro-ph/0212029},
year = {2007}
}
Comments
To be published in "CNO in the Universe", ASP Conference Series, C. Charbonnel, D. Schaerer & G. Meynet (eds.)