Abstract
High-resolution spectra of the 158 μm fine-structure line of ionized carbon have been obtained with a heterodyne spectrometer toward a number of galactic molecular clouds. Strongly reversed C II line profiles are seen in sources noted for similar behavior in low-J 12CO. The C+ producing the optically thick (τ≥1) absorption component is cool or subthermally excited, with excitation temperatures typically less than 25–50 K. Column densities for the absorption component are ≥;1018 cm-2, similar to values predicted by UV-photodissociation models for C II emitting gas. Thus the total C+ column density in the vicinity of these molecular clouds is significantly greater than previously estimated from integrated intensity measurements.
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© 1990 Springer Science+Business Media Dordrecht
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Betz, A.L., Boreiko, R.T., Zmuidzinas, J. (1990). Heterodyne Spectroscopy of C II in Molecular Clouds. In: Watt, G.D., Webster, A.S. (eds) Submillimetre Astronomy. Astrophysics and Space Science Library, vol 158. Springer, Dordrecht. https://doi.org/10.1007/978-94-015-6850-0_45
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DOI: https://doi.org/10.1007/978-94-015-6850-0_45
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