Radio and soft X-ray investigation of the solar flares of February 4, 1986

The 3B flare of February 4, 1986 is studied comprehensively. The escape electrons accelerated to 10-100 keV at the top of coronal loop are confirmed by type III bursts. The energetic electron beams moved downward trigger the eruptions in the lower layer of the solar atmosphere. The radio and soft X-ray bursts are interpreted, respectively, by the maser mechanism and evaporation effect. Finally, the important role of energetic electron beams in solar flares is pointed out.