A 21 micron emission feature in four proto-planetary nebulae

Journal Article · Sun Oct 01 04:00:00 EDT 1989 · Astrophysical Journal; (USA)

DOI:https://doi.org/10.1086/185550· OSTI ID:5021817

Kwok, S; Volk, K M; Hrivnak, B J ^[1]

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1. Calgary Univ. (Canada) NASA, Ames Research Center, Moffett Field, CA (USA) Valparaiso Univ., IN (USA)

The discovery of an unidentified emission feature at 21 microns in the LRS spectra of four IRAS sources is reported. These objects all show large FIR excesses due to a circumstellar dust envelope surrounding a carbon-rich central star and are likely to be in the evolutionary phase between the asymptotic giant branch and planetary nebula stages. The strength of the feature and the carbon richness of the objects suggest that this feature is due to the bending mode of a transient carbon-bearing molecule. 16 refs.

• OSTI ID: 5021817
• Journal Information: Astrophysical Journal; (USA), Journal Name: Astrophysical Journal; (USA) Vol. 345; ISSN ASJOA; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

640102* -- Astrophysics & Cosmology-- Stars & Quasi-Stellar
Radio & X-Ray Sources
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CARBON STARS
COSMIC DUST
DUSTS
ELECTROMAGNETIC RADIATION
ENERGY SPECTRA
FAR INFRARED RADIATION
GIANT STARS
INFRARED RADIATION
MAIN SEQUENCE STARS
NEBULAE
PLANETARY NEBULAE
RADIATIONS
RED GIANT STARS
SPECTRA
SPECTROSCOPY
STAR EVOLUTION
STARS