The search for giant radio galaxies in the PS 102 survey

Abstract

The possibility of selecting extended radio sources that are potential candidates for giant radio galaxies among objects in the Pushchino catalog at 102 MHz is considered. The method used is based on the analysis of objects in a α1–α2 diagram, where α1 and α2 are two-frequency spectral indices (Sν ∼ ν−α), formally calculated using 102–365 and 365–1400 MHz data, based on the identifications of Pushchino radio sources with objects of the Texas (365 MHz) and Green Bank (1400 MHz) catalogs. The calculated spectra are abnormally steep at 102–365 MHz and flat or even inverted at 365–1400 MHz, due to the fact that the 365-MHz flux densities of extended radio sources measured with the Texas radio interferometer are appreciably underestimated. Ten objects among the fifteen Pushchino radio sources selected using this criterion proved to be already known large radio galaxies. The possibility of improving the efficiency of the method by using larger samples and applying some additional criteria selecting candidate giant radio galaxies is considered.