THE UNUSUAL SUPERNOVA REMNANT G76.9- THE LOW-FREQUENCY RADIO SPECTRUM(1.0 )

G76.9+1.0 is an unusual radio source which is interpreted as a filled- centre supernova remnant (SNR). New 232-MHe observations of a field co ntaining G76.9+1.0 have been combined with a re-analysis of existing o bservational data to derive the low-frequency spectrum of the SNR. Its spectral index has a value of about 0.6 above 1 GHz, and appears to f latten below that frequency. This may indicate a ''break'' in the spec trum below 1 GHz. However, further observations at frequencies below 4 00 MHz will be required before this can be firmly established. The low -frequency spectra of several other radio sources in the field surroun ding G76.9+1.0 were also derived, partially to confirm the validity of the 232-MHz flux densities but also to provide new lower frequency da ta for these objects. They include several H II regions and some extra galactic sources. Two Of the latter have rather steep spectra and meri t further study.