Expansion of the supernova remnant 3C 10 (Tycho) and its implications for models of young remnants

Open Access
Publisher Website
Google Scholar
Abstract
The remnant of Tycho Brahe's supernova (3C 10) was observed with the Westerbork telescope at 21 cm in 1971 and 1979, and these measurements have been used to determine the radial expansion rate. The average value obtained is 0.256 ± 0.026 arcsec yr–1 . Although this seems to be higher than that found optically, the individual radio and optical data points agree well within the errors. The apparent discrepancy is primarily the result of a low expansion speed at the position of the most prominent nebulosity, and we attribute this to deceleration caused by the higher density of material. While the expansion speed only marginally exceeds that predicted by the Sedov solution, the confirmation lent by the optical data suggests a possible real effect. We consider two plausible explanations: the remnant is not yet fully in the adiabatic phase; or the dynamics are being modified by the evaporation of neutral material behind the shock front. Whether either of these is the correct explanation, it is clear that swept-up material now dominates the dynamics of 3C 10. No significant change in flux density was detected at a level which favours models where particle acceleration/field amplification are occurring over that of simple adiabatic expansion.

This publication has 0 references indexed in Scilit: