ar X iv : a st ro - p h / 06 04 03 0 v 1 3 A pr 2 00 6 High resolution infrared spectroscopy of the old open cluster NGC 6791
نویسندگان
چکیده
We report abundance analysis for 6 M giant members of the old open cluster NGC 6791, based on infrared spectroscopy (1.5−1.8 μm) at R=25,000, using the NIRSPEC spectrograph at the Keck II telescope. We find the iron abundance 〈[Fe/H]〉 = +0.35 ± 0.02, confirming the super solar metallicity of this cluster derived from optical medium-high resolution spectroscopy. We also measure C, O and other alpha element abundances, finding roughly solar [alpha/Fe] and 1 Data presented herein were obtained at the W.M.Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W.M. Keck Foundation.
منابع مشابه
ar X iv : a st ro - p h / 06 01 02 7 v 1 2 J an 2 00 6 The metallicity of the old open cluster NGC 6791 1
We have observed four red clump stars in the very old and metal-rich open cluster NGC 6791 to derive its metallicity, using the high resolution spectrograph SARG mounted on the TNG. Using a spectrum synthesis technique we obtain an average value of [Fe/H] = +0.47 (±0.04, r.m.s. = 0.08) dex. Our method was tested on μ Leo, a well studied metal-rich field giant. We also derive average oxygen and ...
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