Imaging solar flares in hard X-rays and gamma raysfrom balloon-borne platforms

Hard X-rays and gamma rays carry the most direct evidence available for the roles of accelerated particles in solar flares. An approach that employs a spatial Fourier-transform technique for imaging the sources of these emissions is described and plans for developing a balloon-borne gamma ray imaging device (GRID) based on this instrumental approach is presented. This instrument, GRID on a balloon, would enable observations with a 1.6 arcsecond angular resolution, 10 millisecond time resolution, and whole-Sun field of view on long-duration balloon flights during MAX 1991.