Detection of a new, low-brightness supernova remnant possibly associated with EGRET sources

J. A. COMBI; G. E. ROMERO; P. BENAGLIA; J. L. JONAS

ASTRONOMY AND ASTROPHYSICS

EDP Sciences

Año: 2001 vol. 366 p. 1047 - 1052

0004-6361

We report on the discovery of a shell-type supernova remnant in the southern sky. It is a large ( ~ 8deg x 8deg), low-brightness source with a nonthermal radio spectrum, which requires background filtering to isolate it from the diffuse background emission of the Galaxy. Three 3EG gamma -ray sources are spatially correlated with the radio structure. We have made 21-cm line observations of the region and found that two of these sources are coincident with HI clouds. We propose that the gamma -ray emission is the result of hadronic interactions between high-energy protons locally accelerated at the remnant shock front and atomic nuclei in the ambient clouds.