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Keck-Nirspec Infrared OH Lines: Oxygen Abundances in Metal-Poor Stars Down to [Fe/H] = -2.9

Jorge Melendez·Beatriz Barbuy
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Abstract

Infrared OH lines at 1.5 - 1.7 um in the H band were obtained with the NIRSPEC high-resolution spectrograph at the 10m Keck Telescope for a sample of seven metal-poor stars. Detailed analyses have been carried out, based on optical high-resolution data obtained with the FEROS spectrograph at ESO. Stellar parameters were derived by adopting infrared flux method effective temperatures, trigonometric and/or evolutionary gravities and metallicities from FeII lines. We obtain that the sample stars with metallicities [Fe/H] < -2.2 show a mean oxygen abundance [O/Fe] ~ 0.54, for a solar oxygen abundance of epsilon(O) = 8.87, or [O/Fe] ~ 0.64 if epsilon(O) = 8.77 is assumed.

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Jorge Melendez, Beatriz Barbuy. 2002-07-31. Keck-Nirspec Infrared OH Lines: Oxygen Abundances in Metal-Poor Stars Down to [Fe/H] = -2.9. https://doi.org/10.1086/341142

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