author={D. Howe and T. Millar and D. A. Williams},
  journal={Monthly Notices of the Royal Astronomical Society},
The gas-phase chemistry in the remnant superwind of a carbon-rich red giant star, during its transition to a planetary nebula, is investigated. The interacting stellar winds model is used. It is found that during the first few hundred years of transition, significant abundances of a few small molecules and ions (e.g. CH + , CH + 2 , CH + 3 , CH, CH 2 , NH) may occur in the thin, dense, shocked shell of gas predicted by this model, but that most molecules observed in protoplanetary nebulae will… Expand
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