Abstract
A brief introduction into the diagnostic capabilities and results of radio waves from coronal plasmas of the Sun and other late-type stars is presented. These coronal emissions show that the plasma is in a dynamic state with time scale down to a few tens of microseconds. Gyrosynchrotron emission in flares reveal the presence of relativistic electrons, which, in active stars, seem to persist even during quasi-quiet (quiescent) intervals. Coherent emissions of solar electron beams by the two-stream instability has been discovered up to 8 GHz. Particularly efficient emitters are trapped electrons having a loss-cone distribution. This is probably the most frequent cause of highly polarized stellar radio flares. Of greatest interest are emissions by unstable currents and shocks, which have been identified in the solar corona. A general introduction into some basic theories, but not a review, is given, illustrated with recent observations. A more extended introduction can be found in Benz (1993).
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© 1996 Springer-Verlag Berlin Heidelberg
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Benz, A.O. (1996). Radio astronomical diagnostics. In: Chiuderi, C., Einaudi, G. (eds) Plasma Astrophysics. Lecture Notes in Physics, vol 468. Springer, Berlin, Heidelberg. https://doi.org/10.1007/BFb0102545
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DOI: https://doi.org/10.1007/BFb0102545
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