Old Supernova Remnants: Structure and Source of Radio Emission

Abstract

Contour maps at 102· 5 MHz for 12 galactic SNRs of large angular size in the northern sky are presented. The observations were made with an angular resolution of 48' x24' sec(55° - 8) using the BSA telescope of the Lebedev Physical Institute. All sources were mapped in total intensity. Our results indicate that the contribution to the radiation of observed SNRs from swept up cosmic ray electrons is small. The characteristics of the observed sources are discussed.