Expansion of the Supernova Remnant RCW 103

Abstract

A new CCD image of the supernova remnant RCW 103 was taken in 1995 to compare with a photographic plate taken in 1970. We calculated the proper-motion expansion of the outer edge and several filaments by comparing radial slices through each of the datasets. The mean expansion rate of the outer edge is 178 ±072 per 25 years, or about 1100 km s“1. At this velocity the remnant is most likely around 2000 years old. In addition, it must have made the transition from the double-shock phase of evolution to the point-blast phase fairly recently for the initial energy of the supernova explosion to be within a reasonable range.