Analysis of the disappearing filament and flare of 7 May 1992

By using Yohkoh soft X-ray data, H alpha ot filtergrams, and radio data, th e activation of the disappearing filament and the flare eruption on 7 May 1 992 have been studied. Main conclusions are as follows: (1) the emergence o f new magnetic flux tends to affect the pre-existing X-ray loops, which usu ally appear in arcades spanning Ha filament, changing the magnetic environm ent of the filament, and then enhance the current in the filament. Therefor e newly emerging Aux plays a fundamental role in the destabilization of thi s filament. (2) According to the H alpha data and the rising motion of the filament, the corresponding current variation in the filament has been calc ulated. It seems that the current interruption may be a possible trigger me chanism for this filament disappearance. (3) The magnetic field strength an d the energy flux of energetic electrons in the source region of microwave bursts have been estimated by using the microwave spectrum. During the main phase, the mean magnetic strength and the energy flux of energetic electro ns are about 300-400 G and 1 x 10(11) erg cm(-2) s(-1), respectively. (4) T he energy provided by reconnection of the current sheet and the total energ y of the current filament are estimated and we show that there is enough en ergy stored in the filament to feed the 7 May, 1992 flare.