Abstract
The recombination lines of highly excited carbon atoms near 25 MHz were detected in the directions of DR 21, S140 and L 1407. The line intensity is about 10-3 of the background level, with the width varying between and 8 KHz and the line of sight radial velocity close to zero. Evaluating the physical parameters of the medium responsible for line formation we have obtained the electron number density in DR 21 and S 140 below 1 cm-3. The estimate for the cloud L 1407 is, with allowance for the data on the background continuum absorbtion, 0.05 to 0.1 cm-3 with an electron temperature of 10 to 20 K. The highly sensetive techniques of decameter band radio spectroscopy suggest way of detecting low density cold interstellar plasmas with ionized carbon in various galactic objects.
This is a preview of subscription content, log in via an institution.
Buying options
Tax calculation will be finalised at checkout
Purchases are for personal use only
Learn about institutional subscriptionsPreview
Unable to display preview. Download preview PDF.
References
Abramenkov, E.A. (1985) ‘Low frequency radio observations of HII regions: The galactic disk region 147° < 1 < 153° Sov. Astron.J., 62, 1057–1064.
Anantharamaiah, K.R., Payne, H.E., Erickson W.C. (1988) ‘Detection of carbon recombination lines below 100 MHz towards the Galactic Centre and M16’, Mon. Not. R. Astr. Soc. 235, 151–160.
Falgarone, E. (1980) ‘Carbon and sulfure ionized regions in dark clouds’, in P.A. Shaver (ed.), Radio Recombination Lines, pp. 141–147.
Knapp, G.R., Brown R.L., Kuiper, T.B.K. and Kakar R.K. (1976) ‘Carbon recombination line observations of the Sharpless 140 region’, Astrophysical J. 204, 781–788.
Konovalenko, A.A.(1984) ‘Detection of decameter wave radio lines of excited carbon in some galactic objects’, Sov. Astron. J. Lett., 10, 912–917.
Konovalenko, A.A. ‘Review of decameter wave recombination lines: problems and methods’, this issue.
Pankonin, V, Thomasson, P. and Barsuhn, J.A. (1977) ‘Survey of radio recombination lines from HI regions and associated HII regions’, Astron, and Astrophys., 54, 335–344.
Shaver, P.A.(1975) ‘Theoretical intencities of low frequency recombination lines’, Pramana 5, 1–28.
Valles, I.(1987) ‘The neutral interface ajoining HII regions’, Astrophys. and Space Sci. 127, 339–351.
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 1990 Kluwer Academic Publishers
About this chapter
Cite this chapter
Golynkin, A.A., Konovalenko, A.A. (1990). Detection of Carbon Recombination Lines at Decameter Wavelengths in Some Galactic Objects. In: Gordon, M.A., Sorochenko, R.L. (eds) Radio Recombination Lines: 25 Years of Investigation. Astrophysics and Space Science Library, vol 163. Springer, Dordrecht. https://doi.org/10.1007/978-94-009-0625-9_20
Download citation
DOI: https://doi.org/10.1007/978-94-009-0625-9_20
Publisher Name: Springer, Dordrecht
Print ISBN: 978-94-010-6768-3
Online ISBN: 978-94-009-0625-9
eBook Packages: Springer Book Archive