FRICAT - FIRST Catalog of FR I Radio Galaxies

Overview

The authors have built a catalog of 219 Fanaroff and Riley class I edge-darkened radio galaxies (FR Is), called FRICAT, that is selected from a published sample and obtained by combining observations from the NVSS, FIRST, and SDSS surveys. They included in the catalog the sources with an edge-darkened radio morphology, redshift <= 0.15, and extending (at the sensitivity of the FIRST images) to a radius r larger than 30 kpc from the center of the host. The authors also selected an additional sample (sFRICAT) of 14 smaller (10 < r < 30 kpc) FR Is, limiting to z < 0.05. The hosts of the FRICAT sources are all luminous (-21 >~ M_r >~ 24), red early-type galaxies with black hole masses in the range 10⁸ <~ M_BH <~ 3 x 10⁹ solar masses); the spectroscopic classification based on the optical emission line ratios indicates that they are all low excitation galaxies. Sources in the FRICAT are then indistinguishable from the FR Is belonging to the Third Cambridge Catalogue of Radio Sources (3C) on the basis of their optical properties. Conversely, while the 3C-FR Is show a strong positive trend between radio and [O III] emission line luminosity, these two quantities are unrelated in the FRICAT sources; at a given line luminosity, they show radio luminosities spanning about two orders of magnitude and extending to much lower ratios between radio and line power than 3C-FR Is. The authors' main conclusion is that the 3C-FR Is represent just the tip of the iceberg of a much larger and diverse population of FR Is.

This HEASARC table contains both the 219 radio galaxies in the main FRICAT sample listed in Table B.1 of the reference paper and the 14 radio galaxies in the additional sFRICAT sample listed in Table B.2 of the reference paper. To enable users to distinguish from which sample an entry has been taken, the HEASARC created a parameter galaxy_sample which is set to 'M' for galaxies from the main sample, and to 'S' for galaxies from the supplementary sFRICAT sample.

Throughout the paper, the authors adopted a cosmology with H₀ = 67.8 km s^-1 Mpc^-1, Omega_M = 0.308, and Omega_Lambda = 0.692 (Planck Collaboration XIII 2016).

Catalog Bibcode

2017A&A...598A..49C

References

FRICAT: A FIRST catalog of FR I radio galaxies
    Capetti, A., Massaro, F., Baldi, R.D.
   <Astron. Astrophys. 598, A49 (2017)>
   =2017A&A...598A..49C    (SIMBAD/NED BibCode)

Provenance

This table was created by the HEASARC in February 2017 based on electronic versions of Tables B.1 and B.2 that were obtained from the Astronomy & Astrophysics website.

Parameters

Galaxy_Sample
This HEASARC-created the parameter is set to 'M' for the 219 radio galaxies from the main sample, and to 'S' for the 14 radio galaxies from the supplementary sFRICAT sample.

Name
The J2000.0 position-based SDSS source designation.

RA
The Right Ascension of the radio galaxy in the selected equinox. This was given to an implicit precision of 0.01 seconds of time in the SDSS name.

Dec
The Declination of the radio galaxy in the selected equinox. This was given to an implicit precision of 0.1 arcseconds in the SDSS name.

LII
The Galactic Longitude of the radio galaxy.

BII
The Galactic Latitude of the radio galaxy.

Redshift
The redshift of the radio galaxy, taken from Best & Heckman (2012, MNRAS, 421, 1569).

NVSS_Flux_1p4_GHz
The NVSS 1.4-GHz flux density of the radio galaxy, taken from Best & Heckman (2012, MNRAS, 421, 1569).

O_III_Flux
The O [III] line flux of the radio galaxy, in erg s^-1 cm^-2, taken from the MPA-JHU DR7 release of spectrum measurements.

Rmag
The SDSS DR7 r-band AB magnitude of the radio galaxy, corrected for Galactic extinction, taken from the MPA-JHU DR7 release of spectrum measurements.

Dn_4000_Index
The Dn(4000) spectroscopic index of the radio galaxy, taken from the MPA-JHU DR7 release of spectrum measurements. Dn(4000) is defined according to Balogh et al. (1999, ApJ, 527, 54) as the ratio between the flux density measured on the "red" side of the Ca II break (4000-4100 Angstroms) and that on the "blue" side (3850-3950 Angstroms). Low redshift (z < 0.1) red galaxies show Dn(4000) = 1.98 +/- 0.05, which is a value that decreases to 1.95 +/- 0.05 for 0.1 < z < 0.15 galaxies (Capetti & Raiteri 2015, A&A, 580, A73). The presence of young stars or of non-stellar emission reduces the Dn(4000) index. The authors estimate a median error of 0.03 for the Dn(4000) index values quoted herein.

Stellar_Dispersion
The stellar velocity dispersion of the radio galaxy sigma_*, in km s^-1, taken from the MPA-JHU DR7 release of spectrum measurements. The authors estimate a median error of 9 km s^-1 for the stellar dispersion values quoted herein.

Concentration_Index
The concentration index C_r of the radio galaxy taken directly from the SDSS database. The authors estimate a median error of 0.08 for the concentration index values quoted herein. The concentration index C_r is defined as the ratio of the radii including 90% and 50% of the light in the r band, respectively. Early-type galaxies (ETGs) have higher values of C_r than do late-type galaxies. Two thresholds have been suggested to define ETGs: a more conservative value at C_r >~ 2.86 and a more relaxed selection at C_r >~ 2.6. See Section 4.1 of the reference paper for more details.

Log_1p4_GHz_Luminosity
The logarithm of the radio luminosity nu*L(nu) at 1.4 GHz, in erg s^-1, calculated from the 1.4-GHz flux density and the redshift of the radio galaxy using the Planck-derived cosmological parameters listed in the Overview above.

Log_O_III_Luminosity
The logarithm of the [O III] line luminosity, in erg s^-1, calculated from the [O III] flux and the redshift of the radio galaxy using the Planck-derived cosmological parameters listed in the Overview above.

Log_Black_Hole_Mass
The logarithm of the black hole mass M_BH in the radio galaxy, in solar masses. The black hole masses were estimated by the authors from the stellar velocity dispersion and the sigma_* - M_BH relation of Tremaine et al. (2002, ApJ, 574, 740). The errors in the M_BH values are dominated by the spread of the relation used (rather than by the errors in the measurements of sigma_*, resulting in an uncertainty of a factor of ~2.

Contact Person

Questions regarding the FRICAT database table can be addressed to the HEASARC Help Desk.

Page Author: Browse Software Development Team
Last Modified: Monday, 16-Sep-2024 17:27:43 EDT