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arXiv · 0808.2480

Chemical Analysis of Five Red Giants in the Globular Cluster M10 (NGC 6254)

Sharina Haynes·Geoffrey Burks·Christian I. Johnson·Catherine A. Pilachowski
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Abstract

We have determined Al, $α$, Fe-peak, and neutron capture elemental abundances for five red giant branch (RGB) stars in the Galactic globular cluster M10. Abundances were determined using equivalent width analyses of moderate resolution (R$\sim$15,000) spectra obtained with the Hydra multifiber positioner and bench spectrograph on the WIYN telescope. The data sample the upper RGB from the luminosity level near the horizontal branch to about 0.5 mag below the RGB tip. We find in agreement with previous studies that M10 is moderately metal-poor with [Fe/H]=-1.45 ($σ$=0.04). All stars appear enhanced in Al with $<$[Al/Fe]$>$=+0.33 ($σ$=0.19), but no stars have [Al/Fe]$\ga$+0.55. We find the $α$ elements to be enhanced by +0.20 to +0.40 dex and the Fe--peak elements to have [el/Fe]$\sim$0, which are consistent with predictions from type II SN ejecta. Additionally, the cluster appears to be r-process rich with $<$[Eu/La]$>$=+0.41.

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Sharina Haynes, Geoffrey Burks, Christian I. Johnson, Catherine A. Pilachowski. 2008-08-18. Chemical Analysis of Five Red Giants in the Globular Cluster M10 (NGC 6254). https://doi.org/10.1086/592717

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