ISSN:
1572-9508
Keywords:
21 μm Proto
;
Planetary Nebulae
;
Carbon Dust: PAHs
;
Stellar Evolution
Source:
Springer Online Journal Archives 1860-2000
Topics:
Physics
Notes:
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.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00430116
Permalink