FRIICAT: A FIRST catalog of FR~II radio galaxies
Abstract
We built a catalog of 122 FR~II radio galaxies, called FRIICAT, selected from a published sample obtained by combining observations from the NVSS, FIRST, and SDSS surveys. The catalog includes sources with redshift ≤ 0.15, an edge-brightened radio morphology, and those with at least one of the emission peaks located at radius r larger than 30 kpc from the center of the host. The radio luminosity at 1.4 GHz of the \ sources covers the range L1.4 1039.5 - 1042.5 . The \ catalog has 90\% of low and 10\% of high excitation galaxies (LEGs and HEGs), respectively. The properties of these two classes are significantly different. The FRIICAT LEGs are mostly luminous (-20 Mr -24), red early-type galaxies with black hole masses in the range 108 M BH 109 M; they are essentially indistinguishable from the FR~Is belonging to the FRICAT. The HEG FR~IIs are associated with optically bluer and mid-IR redder hosts than the LEG FR~IIs and to galaxies and black holes that are smaller, on average, by a factor 2. FR~IIs have a factor 3 higher average radio luminosity than FR~Is. Nonetheless, most ( 90 \%) of the selected FR~IIs have a radio power that is lower, by as much as a factor of 100, than the transition value between FR~Is and FR~IIs found in the 3C sample. The correspondence between the morphological classification of FR~I and FR~II and the separation in radio power disappears when including sources selected at low radio flux thresholds, which is in line with previous results. In conclusion, a radio source produced by a low power jet can be edge brightened or edge darkened, and the outcome is not related to differences in the optical properties of the host galaxy.