Galactic supernova remnants: radio evolution and population characteristics.
Abstract
The dependence of the surface brightness of shell supernova remnants (SNRs) at 408 MHz on distance from the galactic plane (z) is discussed. The cause of this dependence and its relevance to the understanding of the evolution of SNR radio emission are considered. It is shown that the observational statistics (of cumulative number counts) favor an interstellar origin for the magnetic field in 'middle-aged' SNRs and that the surface brightness gradients across faint SNRs suggest that the magnetic field in the 'old' phase is interstellar in origin. The SNR AD 1006 is found to be a young SNR with an anomalously low surface brightness, which is accounted for by assuming that the z-dependence of surface brightness for old SNRs is also applicable to young SNRs.
- Publication:
-
Australian Journal of Physics
- Pub Date:
- March 1979
- DOI:
- 10.1071/PH790079
- Bibcode:
- 1979AuJPh..32...79C
- Keywords:
-
- Radio Emission;
- Stellar Evolution;
- Supernova Remnants;
- Interstellar Magnetic Fields;
- Stellar Structure;
- Astrophysics;
- Galaxy:Supernova Remnants;
- Radio Radiation:Supernova Remnants;
- Supernova Remnants:Shells