The high-intensity components of solar radiation are defined as those components whose emitting regions occasionally attain brightness temperatures of 1010 deg K or more. They have been referred to individually as enhanced radiation (or noise storms), outbursts and isolated bursts.

Theories of origin in terms of thermal processes are examined and none are found capable of explaining the observational data. It is concluded that all three components are generated by the ordered (non-thermal) motion of electrons.