J/MNRAS/479/807 Catalogue of faint local radio AGN (Lofthouse+, 2018)
A catalogue of faint local radio AGN and the properties of their host galaxies.
Lofthouse E.K., Kaviraj S., Smith D.J.B., Hardcastle M.J.
<Mon. Not. R. Astron. Soc. 479, 807 (2018)>
=2018MNRAS.479..807L 2018MNRAS.479..807L (SIMBAD/NED BibCode)
ADC_Keywords: Active gal. nuclei; Radio sources; Radio continuum
Keywords: active galaxies; luminosity function; radio continuum
Abstract:
We present a catalogue of 2210 local (z<0.1) galaxies that contain
faint active galactic nuclei (AGN). We select these objects by
identifying galaxies that exhibit a significant excess in their radio
luminosities, compared to what is expected from the observed levels of
star formation activity in these systems. This is achieved by
comparing the optical (spectroscopic) star formation rate (SFR) to the
1.4GHz luminosity measured from the Faint Images of the Radio Sky at
Twenty centimeters survey. The majority of the AGN identified in this
study are fainter than those in previous work, such as in the Best and
Heckman (2012, Cat. J/MNRAS/421/1569) catalogue. We show that these
faint AGN make a non-negligible contribution to the radio luminosity
function at low luminosities (below 1022.5W/Hz), and host ∼13 per
cent of the local radio luminosity budget. Their host galaxies are
predominantly high stellar-mass systems (with a median stellar mass of
1011 M), are found across a range of environments (but typically in
denser environments than star-forming galaxies) and have early-type
morphologies. This study demonstrates a general technique to identify
AGN in galaxy populations where reliable optical SFRs can be extracted
using spectro-photometry and where radio data are also available so
that a radio excess can be measured. Our results also demonstrate that
it is unsafe to infer SFRs from radio emission alone, even if bright
AGN have been excluded from a sample, since there is a significant
population of faint radio AGN that may contaminate the radio-derived
SFRs.
Description:
We present a catalogue of 2210 local (z<0.1) galaxies that contain
faint active galactic nuclei (AGN). We select these objects by
identifying galaxies that exhibit a significant excess in their radio
luminosities, compared to what is expected from the observed levels of
star formation activity in these systems. This is achieved by
comparing the optical (spectroscopic) star formation rate (SFR) to the
1.4 GHz luminosity measured from the Faint Images of the Radio Sky at
Twenty centimeters survey.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
catalog.dat 104 2210 Catalogue of faint local radio AGN
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See also:
VIII/92 : The FIRST Survey Catalog, Version 2014Dec17 (Helfand+ 2015)
J/MNRAS/421/1569 : Properties of 18286 SDSS radio galaxies (Best+, 2012)
Byte-by-byte Description of file: catalog.dat
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Bytes Format Units Label Explanations
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1- 9 F9.5 deg RAdeg Right Ascension (J2000)
11- 19 F9.5 deg DEdeg Declination (J2000)
21- 27 F7.5 --- z Redshift
29- 50 E22.17 W/Hz LFIRST FIRST Luminosity
52- 59 F8.5 [Msun/yr] logSFRF Logarithm of star formation rate derived
from FIRST luminosity
61- 68 F8.5 [Msun/yr] logSFRM Logarithm of star formation rate from
SDSS MPA-JHU catalogue
70- 77 F8.5 [Msun] logM* Logarithm of stellar mass
79- 90 F12.7 --- BT ?=-999 Bulge-to-total light ratio
92-101 F10.5 [Msun] logMhalo ?=-999 Logarithm of halo mass
103-104 I2 --- BPT [-1/5] BPT classification (1)
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Note (1): BPT classification code as follows:
-1 = Unclassified
1 = star forming
2 = low S/N star forming
3 = Composite
4 = AGN (Non-LINER)
5 = LINER
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Acknowledgements:
Emma Lofthouse, e.k.lofthouse(at)gmail.com
History:
* 24-Aug-2018: on-line version
* 13-Jun-2019: complete catalog ...
(End) E. Lofthouse [Univ. of Hertfordshire], P. Vannier [CDS] 23-Aug-2018