Back to Volume
Paper: A Spitzer Sample of S-type AGB Stars
Volume: 445, Why Galaxies Care about AGB Stars II: Shining Examples and Common Inhabitants
Page: 209
Authors: Smolders, K.; Blommaert, J.; Decin, L.; Van Winckel, H.; Hony, S.; Sloan, G.; and the Spitzer S-star group
Abstract: We present a set of Spitzer IRS spectra (5–35 μm) of a sample of intrinsic S stars, covering the entire MS–S–SC sequence. We acknowledge that, due to the selection criteria employed, the sample is biased towards lower mass-loss rates. Most stars do not show significant emission features. For the dust-rich stars, we can conclude that the dust resembles the dust around M stars, with alumina, silicates and magnesium-iron-oxides as the strongest emission features. Furthermore, we detect PAH emission features in four S stars and confirm the correlation between the temperature of the central star and the centroid wavelength of the 7.9 μm feature. We argue that the mixture of hydrocarbons we see in these S stars has a rich aliphatic component.
Back to Volume