Carbon molecules in the inner wind of the oxygen-rich Mira IK Tauri

Debiprosad Duari; Isabelle Cherchneff; Karen Willacy

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Carbon molecules in the inner wind of the oxygen-rich Mira IK Tauri

Debiprosad Duari·Isabelle Cherchneff·Karen Willacy

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Abstract

The gas-phase non-equilibrium chemistry of the inner wind of the oxygen-rich Mira variable IK Tau (NML Tau) is investigated using a physio-chemical model describing the periodically shocked gas close to the stellar photosphere. We predict the formation in large amounts of a few carbon species in the inner envelope, in particular CO$_2$, which has been recently detected with ISO in the spectra of several oxygen-rich semi-regular and Mira stars. The theoretical abundances are also in excellent agreement with values derived from millimeter and sub-millimeter observations, pointing to the fact that some carbon species in oxygen stars do form from shock chemistry in the inner layers and travel the envelope as ``parent'' species.

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Debiprosad Duari, Isabelle Cherchneff, Karen Willacy. 1998-11-17. Carbon molecules in the inner wind of the oxygen-rich Mira IK Tauri. https://arxiv.org/abs/astro-ph/9811263

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