The detection of [C I] in molecular outflows associated with young stellar objects

Christopher K Walker, Gopal Narayanan, Thomas H. Büttgenbach, John E. Carlstrom, Jocelyn Keene, T. G. Phillips

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

The first observations of atomic carbon in molecular outflows are presented. Most of the outflow regions show similar [C I] and 13CO line profiles suggesting the [C I] emission from outflow sources traces the same volume of gas as the CO emission, as previous studies have suggested for molecular clouds in general. The [C I] and CO column densities for the 11 sources surveyed are computed over wing and line center velocities. If the [C I] column densities derived from line center velocities are probing conditions in the ambient cloud in the vicinity of the infrared source, then a comparison of these values indicates the carbon abundance in the low-velocity component of the outflows is essentially the same as in the ambient cloud; there is no evidence for shock enhancement of [C I] in the swept-up material. A map of the [C I] emission from the central arcminute of the luminous DR 21 outflow is presented. The [C I] emission is detected from the two CO outflow lobes; [C I] emission from the southwest lobe appears as a limb-brightened, conical shell. Outflow parameters derived from [C I] are consistent with those derived from CO, suggesting the [C I] emission arises from ambient cloud material swept-up by the outflow. The presence of carbon in the swept-up component of the outflows indicates that gas phase carbon is present deep within molecular clouds and is not confined solely to surface layers.

Original languageEnglish (US)
Pages (from-to)672-679
Number of pages8
JournalAstrophysical Journal
Volume415
Issue number2
StatePublished - Oct 1 1993

Fingerprint

outflow
carbon
molecular clouds
lobes
conical shells
limbs
wings
low speed
detection
young
surface layers
shock
vapor phases
gas
limb
augmentation
surface layer
profiles
gases
shell

Keywords

  • ISM: abundances
  • ISM: jets and outflows
  • ISM: molecules

ASJC Scopus subject areas

  • Space and Planetary Science

Cite this

Walker, C. K., Narayanan, G., Büttgenbach, T. H., Carlstrom, J. E., Keene, J., & Phillips, T. G. (1993). The detection of [C I] in molecular outflows associated with young stellar objects. Astrophysical Journal, 415(2), 672-679.

The detection of [C I] in molecular outflows associated with young stellar objects. / Walker, Christopher K; Narayanan, Gopal; Büttgenbach, Thomas H.; Carlstrom, John E.; Keene, Jocelyn; Phillips, T. G.

In: Astrophysical Journal, Vol. 415, No. 2, 01.10.1993, p. 672-679.

Research output: Contribution to journalArticle

Walker, CK, Narayanan, G, Büttgenbach, TH, Carlstrom, JE, Keene, J & Phillips, TG 1993, 'The detection of [C I] in molecular outflows associated with young stellar objects', Astrophysical Journal, vol. 415, no. 2, pp. 672-679.
Walker CK, Narayanan G, Büttgenbach TH, Carlstrom JE, Keene J, Phillips TG. The detection of [C I] in molecular outflows associated with young stellar objects. Astrophysical Journal. 1993 Oct 1;415(2):672-679.
Walker, Christopher K ; Narayanan, Gopal ; Büttgenbach, Thomas H. ; Carlstrom, John E. ; Keene, Jocelyn ; Phillips, T. G. / The detection of [C I] in molecular outflows associated with young stellar objects. In: Astrophysical Journal. 1993 ; Vol. 415, No. 2. pp. 672-679.
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