Review of Decameter Wave Recombination Lines: Problems and Methods
There we present the main investigation results of the radio recombination lines in the decameter wave range. The detection 10 yeas ago of carbon lines with quantum numbers n > 600 at v < 30 MHz gave new possibilities for studying characteristics of low density interstellar plasma. The most complete data have been received for the source of Cas A. Some problems with regard to choosing a model for the medium forming the carbon lines in the decameter range (n= 768 – 603) and for shorter waves (up to n = 273) have not yet been solved definitively. The methods of high sensetive and interference-proof decameter radio spectroscopy using the UTR-2 radiotelescope allow to record recombination lines of the excited carbon for different components of the interstellar medium.
KeywordsOptical Depth Interstellar Medium Recombination Line Carbon Line Interstellar Plasma
Unable to display preview. Download preview PDF.
- Ershov, A.A., Iliasov, Yu.P., Leht, E.E., Smirnov, G. T., Solodkov, V.T. and Sorochenko, R.L.(1984) ‘The low frequency excited carbon radio lines towards Cassiopeia A. Observations at frequencies 42,57 and 84 KHz’, Sov. Astron. J. Lett. 10, 833–845.Google Scholar
- Konovalenko, A.A. and Sodin, L.G. (1979) ‘Negative result of an attempt to detect hydrogen recombination lines at decameter waves’, Sov. Astron. J. Lett. 5, 663–664.Google Scholar
- Konovalenko, A.A.(1984) ‘Observations of carbon recombination lines at decameter wavelengths in the direction of Cassiopeia A’, Sov.Astron. J. Lett. 10, 846–852.Google Scholar
- Konovalenko, A.A.(1987) ‘An investigations of carbon recombination lines in cosmic radioemission of the decameter range’, Herald of the Academy of Sciences of the Ukrainian SSR (Sov.) 4, 17–31.Google Scholar
- Konovalenko, A.A.(1984) ‘Decameter excited carbon lines in certain galactic objects’, Sov. Astron. J. yeet. 10, 912–917.Google Scholar
- Leht, E.E., Smirnov, G.T. and Sorochenko, R.L.(1989) ‘Observations of the atoms in excitation levels close to the limit in the Galaxy’, Sov. Astron. J.Lett 15, 396–399.Google Scholar
- Pedlar, A. and Davies, E.D.(1980) ‘Low frequency recombination lines’, in P.A. Shaver (ed.), Radio Recombination Lines, Reidel, Dordrecht, pp. 171–183.Google Scholar