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arXiv · 0904.4134

AKARI/IRC observations of heavily obscured oxygen-rich AGB and post-AGB stars

F. Bunzel·D. A. García-Hernández·D. Engels·J. V. Perea-Calderón·P. García-Lario
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Abstract

We present AKARI/IRC observations of a sample of six extremely red IRAS sources, of which three are variable OH/IR stars and the rest are early post-AGB stars. The OH/IR stars show a red continuum with the expected strong 10 micron silicate absorption feature, while the post-AGB stars show an even redder continuum accompanied with a comparably weak silicate absorption. We modelled the spectral energy distributions with DUSTY. While for the OH/IR stars a reasonable fit can be obtained with almost pure silicate dust, the post-AGB stars require a mixture of silicate and carbon-rich dust. We assume that in the latter objects the inner dust shell is carbon-rich, while the outer shells are still oxygen-rich.

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F. Bunzel, D. A. García-Hernández, D. Engels, J. V. Perea-Calderón, P. García-Lario. 2009-10-07. AKARI/IRC observations of heavily obscured oxygen-rich AGB and post-AGB stars. https://arxiv.org/abs/0904.4134

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