Cos-B Observations of Galactic Gamma-Ray Emission (large Scale)

Most of the regions of the sky already observed by COS-B contain parts of the galactic disc. Detailed analysis has been completed of the data from many of these observation periods. In several cases a manual scanning, effective in removing the background events was incorporated in the processing sequence. The data collected during most of these periods have been merged in order to reveal the structure of the large-scale emission. This large-scale emission features a ridge centered on the galactic equator, showing a variable latitude thickness and significant enhancements along the ridge. While such emission is very bright towards the inner galaxy, it becomes very weak, and in places not apparent, outside the solar circle. The energy spectra of the large scale emission from selected regions have been measured. The spectra derived for different longitude bands do not differ, the form of which resembles neither a pure neutral pion nor a power law form.