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Survey for Transiting Extrasolar Planets in Stellar Systems. II. Spectrophotometry and Metallicities of Open Clusters

J. L. Marshall·Christopher J. Burke·D. L. DePoy·Andrew Gould·Juna A. Kollmeier
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Abstract

We present metallicity estimates for seven open clusters based on spectrophotometric indices from moderate-resolution spectroscopy. Observations of field giants of known metallicity provide a correlation between the spectroscopic indices and the metallicity of open cluster giants. We use χ^2 analysis to fit the relation of spectrophotometric indices to metallicity in field giants. The resulting function allows an estimate of the target-cluster giants' metallicities with an error in the method of \pm0.08 dex. We derive the following metallicities for the seven open clusters: NGC 1245, [m/H]=-0.14\pm0.04; NGC 2099, [m/H]=+0.05\pm0.05; NGC 2324, [m/H]=-0.06\pm0.04; NGC 2539, [m/H]=-0.04\pm0.03; NGC 2682 (M67), [m/H]=-0.05\pm0.02; NGC 6705, [m/H]=+0.14\pm0.08; NGC 6819, [m/H]=-0.07\pm0.12. These metallicity estimates will be useful in planning future extra-solar planet transit searches since planets may form more readily in metal-rich environments.

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J. L. Marshall, Christopher J. Burke, D. L. DePoy, Andrew Gould, Juna A. Kollmeier. 2005-06-29. Survey for Transiting Extrasolar Planets in Stellar Systems. II. Spectrophotometry and Metallicities of Open Clusters. https://doi.org/10.1086/432685

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