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Multiple Molecular Winds in Evolved Stars I. A Survey of CO(2-1) and CO(3-2) Emission from 45 Nearby AGB Stars

G. R. Knapp·K. Young·E. Lee·A. Jorissen
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Abstract

This paper describes observations of a new phenomenon in evolved mass-losing AGB stars: the presence of two winds with different expansion velocities. CO(2-1) and CO(3-2) line emission was observed for 45 AGB stars at high velocity resolution and double winds found in 20% of the sample. Highly asymmetric lines were found in six other stars. The data tentatively suggest that double winds occur when the star undergoes a change (pulsational mode, chemical composition) and that the very narrow components represent the onset of a new phase of mass loss.

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G. R. Knapp, K. Young, E. Lee, A. Jorissen. 1997-11-12. Multiple Molecular Winds in Evolved Stars I. A Survey of CO(2-1) and CO(3-2) Emission from 45 Nearby AGB Stars. https://doi.org/10.1086/313111

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