Optical Observations of the Solar Disturbances Causing Type II Radio Bursts

Abstract

Identifications have been established for the solar optical events associated with a number of type II radio bursts. Near or at the limb these have been ejections with velocities exceeding that of sound in the corona. Where the event has been on the disk there has usually been a very bright flare, with some evidence of dark filament activity. In two cases the event was the disappearance (i.e. ejection) of a filament with the subsequent development of flares on either side.