SAS-2 Observations of the High-Energy Gamma Radiation from the VELA Region

Data from a scan of the galactic plane by the SAS-2 high-energy (E> 30 MeV) -ray experiment in the region 2500 < 111 < 2900 show a statistically significant (7 ) excess over the general radiation from the galactic plane for -radiation of energy greater than 100 MeV in the region 2600 <ill < 2700 and -7?5 < b" <00. If the enhanced -radiatinn results from interactions of cosmic rays with galactic matter, as the energy spectrum suggests, it seems reasonable to associate the enhancement with large-scale galactic features, such as spiral-arm segments in that direction, or with the region surrounding the Vela supernova remnant, with which PSR 0833-45 is associated. If the excess is attributed to cosmic rays released from this supernova interacting with the interstellar matter in that region, then on the order of 3 X 1050 ergs would have been released by that supernova in the form of cosmic rays. Subject headings: Galaxy, The - gamma rays - supernovae remnants