COMP2CAT: hunting compact double radio sources in the local Universe

We present a catalog of compact double radio galaxies (hereafter COMP2CAT) listing 43 edge-brightened radio sources whose projected linear size does not exceed 60 kpc, the typical size of their host galaxies. This is the fifth in a series of radio source catalogs recently created, namely: FRICAT, FRIICAT, FR0CAT and WATCAT, each focused on a different class of radio galaxies. The main aim of our analysis is to attain a better understanding of sources with intermediate morphologies between FRIIs and FR0s. COMP2CAT sources were selected from an existing catalog of radio sources based on NVSS, FIRST and SDSS observations for having, mainly, i) edge-brightened morphologies, typical of FRIIs, ii) redshifts z < 0.15 and iii) projected linear sizes smaller than 60 kpc. With radio luminosities at 1.4 GHz 10^{38} < L_{1.4} < 10^{41} erg s^{-1}, COMP2CAT sources appear as the low radio luminosity tail of FRIIs. However, their host galaxies are indistinguishable from those of large-scale radio sources: they are luminous (-21 > M_{r} > -24), red, early-type galaxies with black hole masses in the range of 10^{7.5} < M_BH < 10^{9.5} M_sun. Moreover, all but one of the COMP2CAT sources are optically classifiable as low excitation radio galaxies, in agreement with being the low radio-power tail of FRIs and FRIIs. This catalog of compact double sources, which is ~47 % complete at z<0.15, can potentially be used to clarify the role of compact double sources in the general evolutionary scheme of radio galaxies.