ALIGNMENT OF RADIO, SOFT-X-RAY, HARD X-RAY IMAGES OF SOURCES IN IMPULSIVE AND GRADUAL PHASES OF THE FLARE OF 1992 AUGUST 17-18

This is a preliminary report concerning an impulsive flare, which occu rred on 1992 August 17-18, and was observed with the Nobeyama Radiohel iograph, Yohkoh, and ground-based instruments. Emphasis is put on the alignment of radio images as well as soft X-ray and hard X-ray maps, w hich axe compared in both impulsive and gradual phases. In the impulsi ve phase, which continued for about 30 s, nonthermal emission was most remarkable at 17 GHz, and was also seen in hard X-rays at the souther n part of the SXT source, which was about 14'' width and 80'' long, ex tending in the north-east to south-west direction. Thermal emission wa s detected in soft X-rays and possibly in hard X-rays at the northern Part. During the gradual phase, about 80 s after the onset of the impu lsive phase, thermal emission dominated and was located at the norther n part of the source over the entire energy range. Difficulties are di scussed concerning a possible simple topology of the.magnetic fields.