1. Mid-IR (8?13 ?m) images of the 21 ?m, carbon rich proto-planetary nebulae
- Author
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James R. Graham, Eric Keto, G. W. Hawkins, C. J. Skinner, J. G. Jernigan, John F. Arens, and Margaret Meixner
- Subjects
Physics ,Infrared astronomy ,Infrared ,chemistry.chemical_element ,Astronomy ,Astronomy and Astrophysics ,Astrophysics ,Planetary nebula ,Narrow band ,Stars ,chemistry ,Space and Planetary Science ,Asymptotic giant branch ,Stellar evolution ,Carbon - Abstract
We present 9.7 and 11.8 μm narrow band (Δλ/λ=10%) images of three carbon (C-) rich proto-planetary nebulae with an unusual 21 μm feature: IRAS 07134+ 1005, IRAS 22272+5435, and IRAS 04296+3429. The images were taken at UKIRT using the Berkeley/IGPP/LEA mid-IR camera. All three objects have a bipolar shape adding to the existing evidence that C-rich PPNe are by nature bipolar. Furthermore, we find the same bipolar morphology in a previous study of the C-rich, young planetary nebula, IRAS 21282+5050. We believe these four objects form an evolutionary sequence which links the C-rich asymptotic giant branch (AGB) stars with the C-rich planetary nebulae (PNe). From this evolutionary sequence, we conclude that bipolarity in C-rich PNe begins on the AGB and that the dynamical ages of these PPNe are in fair agreement with theoretical ages for a 0.6 M⊙ hydrogen burning core star.
- Published
- 1994