The Radio Diagnosis of Micro Flare and Coronal Electron Acceleration—The Observations on Radio Spectra

A solar flare contains about several thousands of micro flares¹. Each micro flare releases energy in the forms of thermal, low-freqency waves and accelerated particles. During the flare, most part of the energy is released through electron accelera tion which begins at the preflare phase and continues in the whole flare period. During the different phases of the flare evolution there are different radio radiations(and correlated phenomena at the other wavebands). The multiple-band radio observations and compari sonsamong them can supply importa nt informatin about the process of the time point and the frequency that acceleration begins at. The release of the micro flare energy may account for the different kinds of rapid fine structuers of the radiations. The radio milli second spikes can be the evidence of continuous releases of the energy, because the radia tion sources are located in or near the region of energ yreleasing². The rapid structures of radio radiation has been accepted as the signa ture of the coronal elect ronbeams^3-6. Therefore, observatons of the wide-band spect rometer with the high time and frequency resolutions can be used as a probe to explore the process of the acceleration in detail and make cont ributio ns to the research on preflare heating, initial energy releasing, flare const ructing and evolving. In the present paper we report four radio bursts that contain ms-spikes, spikelike and short- time drifting structures etc.