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Title: Remarkable Chemical Complexity in Planetary Nebulae: A Molecule and Dust Perspective
Abstract Despite model predictions, many planetary nebulae appear to have a relatively rich molecular content. Observational studies of over 30 such objects show the presence of a variety of gas-phase molecules, from simple species such as CN and CS, to more complex organics including H2CO, HC3N, c-C3H2, and CH3CN. Other PNe contain fullerenes; carbonaceous and silicate dust features are also found. Molecular abundances also do not appear to vary with nebular age. Remnant material from the asymptotic giant branch appears to undergo chemical processing in the protoplanetary nebula phase and then is frozen out in planetary nebulae. PN ejecta are thus in part molecular in content and may account for the observation of complex molecules in diffuse clouds.  more » « less
Award ID(s):
2307305 1907910
PAR ID:
10652975
Author(s) / Creator(s):
;
Publisher / Repository:
Cambridge University Press
Date Published:
Journal Name:
Proceedings of the International Astronomical Union
Volume:
19
Issue:
S384
ISSN:
1743-9213
Page Range / eLocation ID:
190 to 207
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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