A MODEL OF IMPULSIVE LOOP FLARES REVISITED

A critical examination of the components of the recent impulsive loop flare model of Takakura is made. It is found that his analysis of the stability of the electron distribution resulting from anomalous heat c onduction is in error and electron plasma waves would not be excited. Rather, in the regions where the electron/proton temperature ratio T-e /T-i less than or similar to 10, electrostatic ion-cyclotron waves wou ld be excited and in the regions where T-e greater than or similar to 10, ion-acoustic waves would be excited. Ratios of T-e/T-i greater tha n or similar to 10 occur only in the late time development behind the conduction fronts. Since the anomalous resistivity due to electrostati c ion-cyclotron waves is fortuitously about 70% of the one used by Tak akura, the general development will follow closely the one calculated by him. Because the anomalous resistivity due to ion-acoustic waves is about 95 times the one used by Takakura, thedevelopment in the parts of the loop where T-e/T-i greater than or similar to 10 for late times would be altered considerably.