FRIICAT: A FIRST catalog of FR II radio galaxies

• Published in: Astronomy and astrophysics (Berlin) Vol. 601
• Main Authors: Capetti, A., Massaro, F., Baldi, R. D.
• Format: Journal Article
• Language: English
• Published: Heidelberg EDP Sciences 01.05.2017
• Subjects: galaxies: active; galaxies: jets; Legs; Luminosity; Morphology; Optical properties; Radio galaxies; Radio sources (astronomy); Red shift
• ISSN: 0004-6361; 1432-0746
• DOI: 10.1051/0004-6361/201630247

Aims. 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. Methods. The radio luminosity at 1.4 GHz of the FRIICAT sources covers the range L1.4 ~ 1039.5−1042.5erg s-1. The FRIICAT 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 ≲ MBH ≲ 109M⊙; 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. Results. 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.