CN and HCN in the infrared spectrum of IRC + 10216

Journal Article · Fri Nov 01 04:00:00 EST 1991 · Astrophysical Journal; (United States)

DOI:https://doi.org/10.1086/170719· OSTI ID:5749587

Wiedemann, G R; Deming, D; Jennings, D E; Hinkle, K H; Keady, J J ^[1]

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1. NASA, Goddard Space Flight Center, Greenbelt, MD (United States) Kitt Peak National Observatory, Tucson, AZ (United States) Los Alamos National Laboratory, NM (United States)

The abundance of HCN in the inner circumstellar shell of IRC + 10216 has been remeasured using the 12-micron nu2 band. The 12-micron lines are less saturated than HCN 3-micron lines previously detected in the spectrum of IRC + 10216. The observed 12-micron HCN line is formed in the circumstellar shell from about 4 to 12 R{sub {asterisk}} in accord with a photospheric origin for HCN. The derived HCN abundance in the 4 to 12 R{sub {asterisk}} region is 4 {times} 10{sup {minus}5} and the column density is 7 {times} 10{sup 18}/sq cm. The 5-micron CN vibration-rotation fundamental band was detected for the first time in an astronomical source. Using four CN lines, the CN column density was determined to be 2.6 {times} 10{sup 15}/sq cm and the rotational temperature to be 8 {plus minus} 2 K. The peal radial abundance is 1 {times} 10{sup {minus}5}. The values for the temperature and abundance are in good agreement with microwave results and with the formation of CN from the photolysis of HCN. 30 refs.

• OSTI ID: 5749587
• Journal Information: Astrophysical Journal; (United States), Journal Name: Astrophysical Journal; (United States) Vol. 382; ISSN ASJOA; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

661300* -- Other Aspects of Physical Science-- (1992-)
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CYANOGEN
ELEMENT ABUNDANCE
HYDROCYANIC ACID
HYDROGEN COMPOUNDS
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INORGANIC ACIDS
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STELLAR ACTIVITY
STELLAR WINDS