Review of Decameter Wave Recombination Lines: Problems and Methods
Abstract
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.
Keywords
Optical Depth Interstellar Medium Recombination Line Carbon Line Interstellar PlasmaPreview
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