High resolution radio observations of 10 unidentified radio sources

Radio observations with angular resolution 2in x 2in cosec delta have been made with the Cambridge 5-km telescope of 10 unidentified radio sources. Deep plates of the optical fields of these sources were available and the survey resulted in one new probable identification, 3C 41. For 3C 469.1, there are a number of possible identifications but there is no radio evidence to favour any particular candidate. The objects associated with the remaining eight sources must be beyond the present plate limit m approximately 23.5. None of the unidentified radio sources possesses a compact central radio component, in contrast to many of the most powerful identified radio sources. It is argued that for compact central objects a correlation exists between non-thermal optical and radio luminosity. (author)