# Spitzer spectra of evolved stars in ω Centauri and their low-metallicity dust production

@article{McDonald2011SpitzerSO,
title={Spitzer spectra of evolved stars in $\omega$ Centauri and their low-metallicity dust production},
author={Iain McDonald and Jacco Th. van Loon and G. C. Sloan and Andrea K. Dupree and Albert A. Zijlstra and Martha L. Boyer and Robert D. Gehrz and Aneurin Evans and Charles E. Woodward and Christian I. Johnson},
journal={Monthly Notices of the Royal Astronomical Society},
year={2011},
volume={417},
pages={20-31}
}
Dust production is explored around 14 metal-poor ([Fe/H] =− 1.91 to −0.98) giant stars in the Galactic globular cluster ω Centauri using new Spitzer Infrared Spectrograph spectra. This sample includes the cluster’s post-asymptotic giant branch (AGB) and carbon stars and is thus the first representative spectral study of dust production in a metal-poor ([Fe/H] < −1) population. Only the more metal-rich stars V6 and V17 ([Fe/H] =− 1.08, −1.06) exhibit silicate emission, while the five other stars… Expand

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