Maps of the Molecular Emission around 18 Evolved

نویسنده

  • K. Z. Stanek
چکیده

We present maps at 20 00 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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تاریخ انتشار 2007