DIFFUSE GALACTIC GAMMA-RAY CONTINUUM

Coordinated observations of the galactic center region using the imagi ng SIGMA instrument and the high-sensitivity OSSE instrument were perf ormed to separate the compact source contributions from the diffuse co mponent. The resulting compact-source corrected spectrum of the galact ic center region is found to be similar in both intensity and spectral index to the spectra obtained from OSSE observations of the galactic plane at l = 25 degrees and 339 degrees, suggesting that the spatial d istribution of the emission is broad and nearly flat in galactic longi tude. At energies below similar to 100 keV, the observed spectrum is f ound to be softer and more intense than predicted by theoretical model s. The observed low energy continuum may be either diffuse in origin, or due to multiple unresolved X-ray sources below the SIGMA detection threshold.