COORDINATED OVRO, BATSE, YOHKOH, AND BBSO OBSERVATIONS OF THE 1992 JUNE 25 M1.4 FLARE

We compare 1-14 GHz microwave images observed at the Owens Valley Radi o Observatory (OVRO), 16-and 256-channel hard X-ray spectra obtained b y the Burst and Transient Source Experiment (BATSE) onboard the Compto n Gamma Ray Observatory (CGRO), soft and and hard X-ray images obtaine d by Yohkoh, and Ha images and magnetograms observed at the Big Bear S olar Observatory (BBSO) for the 1992 June 25 M1.4 flare. We find the f ollowing unique properties for this hare: (1) Soft X-ray emissions con nect two footpoints, the primary microwave source is located at one fo otpoint, and hard X-ray emissions are concentrated in the other footpo int. The radio footpoint is associated with an umbra and may have stro nger magnetic held. (2) During the period that 256-channel BATSE data are available, the hard X-ray photon spectrum consists of two componen ts: a superhot component with a temperature of 8.4 x 10(7) K and emiss ion measure of 2.5 x 10(46) cm(-3) and a power-law component with a ph oton index of 4.2. This is the first time that such a high temperature is reported for the hard X-ray thermal components. It is even more in teresting that such a superhot component is identified before the peak of the hare. The microwave brightness temperature spectra during the same period also demonstrate two components.: a thermal component near the loop top and a nonthermal component at the footpoint of the loop. The microwave thermal component has the similar temperature as that o f the hard X-ray superhot component. These measurements are consistent with the theory that the microwaves and hard X-rays are due to the sa me group of electrons, despite the fact that they are separated by 35, 000 km. (3) The soft X-ray emissions brighten the existing loops and c o-align with H alpha emissions throughout the entire duration of the f lare.