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High resolution optical spectroscopy of IRAS 09425-6040 (=GLMP 260)

D. A. Garcia-Hernandez·C. Abia·A. Manchado·P. Garcia-Lario
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Abstract

We present high resolution optical spectroscopic observations of IRAS 09425-6040, a peculiar, extremely red, C-rich AGB star showing prominent O-rich dust features in its ISO infrared spectrum attributed to crystalline silicates. Our analysis shows that IRAS 09425-6040 is indeed a C-rich star slightly enriched in lithium (log (Li/H) + 12 ~ 0.7) with a low 12C/13C = 15+-6 ratio. We also found some evidence that it may be enriched in s-elements. Combining our results with other observational data taken from the literature we conclude that the star is possibly an intermediate-mass TP-AGB star (M > 3 M_sun) close to the end of its AGB evolution which may have only very recently experienced a radical change in its chemistry, turning into a carbon-rich AGB star.

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D. A. Garcia-Hernandez, C. Abia, A. Manchado, P. Garcia-Lario. 2006-03-10. High resolution optical spectroscopy of IRAS 09425-6040 (=GLMP 260). https://doi.org/10.1051/0004-6361%3A20065009

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