Radio continuum observations of a galactic field centred on the supernova remnant G 73.9+0.9
Abstract
A field centred on the galactic supernova remnant (SNR) G73.9 + 0.9 was mapped in the continuum at 408 and 1420 MHz with the DRAO Synthesis Telescope. The interferometer observations, of resolution 3.4 x 5.8 arcmin^2^ (RA x Dec.) and 1.0 x 1.7 arcmin^2^ (RA x Dec.), respectively, were complemented with single-dish data so that the resulting maps are sensitive to all structures down to the synthesized beam. On the basis of both spectral index and structure, the SNR appears to fit more the description of a filled-centre SNR than that of a shell-type one. The neighbouring H II regions S 104 (G74.8 + 0.6) and SNR CTB 87 (G74.9 + 1.2) were also mapped and the relationship of these sources with their immediate surroundings is discussed. A new 408-MHz map of the large shell-type γ Cygni SNR (G78.2 +2.1) is also presented, which bears a remarkable similarity to the previous 1420-MHz map by Higgs, Landecker & Roger. A small number of previously unknown compact and small-diameter sources are singled out for further study as compact SNR or H II region candidates. A detailed comparison of the association of IRAS point sources with both extended features and compact sources is also carried out.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- September 1990
- Bibcode:
- 1990MNRAS.246..169P