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Molecular line observations of proto-planetary nebulae

J. Alcolea·V. Bujarrabal·A. Castro-Carrizo·C. Sanchez Contreras·R. Neri·J. Zweigle
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Abstract

We present our recent results on mm-wave CO observations of proto-planetary nebulae. These include high-resolution interferometric maps of various CO lines in three well known bipolar PPNe: M1-92, M2-56 and OH231.8+4.2. The global properties of the high velocity molecular emission in post-AGB sources have been also studied, by means of high-sensitivity single dish observations of the J=1-0 and 2-1 lines of 12CO and 13CO. We discuss the implications of these results to constrain the origin of the post-AGB molecular high-velocity winds and the shaping of bipolar PPNe and PNe. In addition, we also present the results of an interferometric map of the molecular envelope around the luminous high-latitude star 89 Her, a low mass post-AGB source which is also a close binary system.

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J. Alcolea, V. Bujarrabal, A. Castro-Carrizo, C. Sanchez Contreras, R. Neri, J. Zweigle. 1999-10-05. Molecular line observations of proto-planetary nebulae. https://arxiv.org/abs/astro-ph/9910081

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