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Maps of the Molecular Emission Around 18 Evolved Stars

K. Z. Stanek·G. R. Knapp·K. Young·T. G. Phillips
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Abstract

We present maps at $20''$ resolution of the molecular emission around 18 evolved stars (14~asymptotic giant branch stars, one supergiant, two proto-planetary nebulae and one planetary nebula), mostly in the $^{12}$CO(3-2) line. Almost all molecular envelopes appear to be at least marginally resolved at this resolution. A substantial fraction of the molecular envelopes show clear deviations from spherical symmetry in the form of elliptical or bipolar envelopes. This indicates that there is a need to implement non-spherical mass loss in current scenarios of the late stages of stellar evolution, in particular on the asymptotic giant branch.

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K. Z. Stanek, G. R. Knapp, K. Young, T. G. Phillips. 1994-12-02. Maps of the Molecular Emission Around 18 Evolved Stars. https://doi.org/10.1086/192214

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