J/MNRAS/457/629 ZFOURGE catalogue of AGN candidates (Cowley+, 2016)
ZFOURGE catalogue of AGN candidates: an enhancement of 160-µm-derived star
formation rates in active galaxies to z = 3.2.
Cowley M.J., Spitler L.R., Tran K.-V.H., Rees G.A., Labbe I., Allen R.J.,
Brammer G.B., Glazebrook K., Hopkins A.M., Juneau S., Kacprzak G.G.,
Mullaney J.R., Nanayakkara T., Papovich C., Quadri R.F., Straatman C.M.S.,
Tomczak A.R., Van Dokkum P.G.
<Mon. Not. R. Astron. Soc., 457, 629-641 (2016)>
=2016MNRAS.457..629C 2016MNRAS.457..629C (SIMBAD/NED BibCode)
ADC_Keywords: Active gal. nuclei ; Redshifts ; Ultraviolet ; Infrared sources ;
X-ray sources ; Radio sources
Keywords: galaxies: active - galaxies: evolution - galaxies: high-redshift -
infrared: galaxies - radio continuum: galaxies - X-rays: galaxies
Abstract:
We investigate active galactic nuclei (AGN) candidates within the
FourStar Galaxy Evolution Survey (ZFOURGE) to determine the impact
they have on star formation in their host galaxies. We first identify
a population of radio, X-ray, and infrared-selected AGN by
cross-matching the deep Ks-band imaging of ZFOURGE with overlapping
multiwavelength data. From this, we construct a mass-complete
(log(M*/M☉)≥9.75), AGN luminosity limited sample of 235 AGN
hosts over z=0.2-3.2. We compare the rest-frame U-V versus V-J
(UVJ) colours and specific star formation rates (sSFRs) of the AGN
hosts to a mass-matched control sample of inactive (non-AGN) galaxies.
UVJ diagnostics reveal AGN tend to be hosted in a lower fraction of
quiescent galaxies and a higher fraction of dusty galaxies than the
control sample. Using 160µm Herschel PACS data, we find the mean
specific star formation rate of AGN hosts to be elevated by
0.34-/-0.07dex with respect to the control sample across all
redshifts. This offset is primarily driven by infrared-selected AGN,
where the mean sSFR is found to be elevated by as much as a factor of
∼5. The remaining population, comprised predominantly of X-ray AGN
hosts, is found mostly consistent with inactive galaxies, exhibiting
only a marginal elevation. We discuss scenarios that may explain these
findings and postulate that AGN are less likely to be a dominant
mechanism for moderating galaxy growth via quenching than has
previously been suggested.
Description:
Our parent sample is comprised of galaxies identified in the ZFOURGE
survey (http://zfourge.tamu.edu), which covers three 11 arcmin x 11
arcmin pointings in the CDFS (Giacconi et al., 2002, Cat.
J/ApJS/139/369), COSMOS (Scoville et al., 2007ApJS..172....1S 2007ApJS..172....1S) and UDS
(Lawrence et al., 2007MNRAS.379.1599L 2007MNRAS.379.1599L, Cat. II/314) legacy fields.
ZFOURGE uniquely employs deep near-IR imaging taken with five
medium-band filters on the FourStar imager mounted on the 6.5m
Magellan Baade telescope.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
agncat.dat 110 649 ZFOURGE AGN catalogue
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See also:
J/ApJ/830/51 : FourStar galaxy evolution survey (ZFOURGE) (Straatman+, 2016)
http://zfourge.tamu.edu : ZFOURGE Home Page
Byte-by-byte Description of file: agncat.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- Name ZFOURGE ID (1)
14- 24 F11.7 deg RAdeg Right ascension (J2000)
26- 36 F11.7 deg DEdeg Declination (J2000)
38- 42 F5.3 --- zph Photometric redshift
44- 50 F7.3 mag Ksmag ?=-99 Ks-band AB magnitude
52 I1 --- UVJ [1/3] UVJ criteria (2)
54- 59 F6.3 [Msun] logM* Host stellar mass
61- 69 E9.4 Lsun LUV Integrated 1216-3200Å rest-frame UV
luminosity
71- 80 E10.4 Lsun LIR Integrated 8-1000um rest-frame IR luminosity
82- 91 E10.4 10-7W LX ?=99 Integrated 0.5-8keV rest-frame X-ray
luminosity (erg/s)
93-102 E10.4 W/Hz L1.4GHz 1.4GHz rest-frame radio luminosity
104 I1 --- IRAGN [0/1]?=-1 AGN detection flag (3)
106-107 I2 --- XrayAGN [0/1]?=-1 Xray detection flag (3)
109-110 I2 --- RadioAGN [0/1]?=-1 Radio fdetection flag (3)
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Note (1): Names: CDFS_NNNNN from ZFOURGE zf_cdfs,
COSMOS_NNNNN from ZFOURGE zf_cosmos
or UDS_NNNNN from ZFOURGE zf_uds.
Note (2): UVJ criteria as follows:
1 = quiescent
2 = star-former
3 = dusty star-former
Note (3): Flags as follows:
-1 = no data
0 = nul detection
1 = positive detection
Infrared AGN (IRAGN) are selected using the colour-colour classifications of
Messias et al. (2012ApJ...754..120M 2012ApJ...754..120M):
z<1.8: Ks-[4.5]> 0, [4.5]-[8.0]> 0
z>1.8: [8.0]-[24]>2.9x([4.5]-[8.0])+2.8, [8.0]-[24]>0.5
Radio AGN (RadioAGN) are selected using the Rees et al.
(2015, Cat. J/MNRAS/455/2731) radio AGN activity index:
SFRRadio/SFRIR+UV>3.0
The minimum root-mean-square (RMS) sensitivity for the 1.4GHz data in
CDFS, COSMOS and UDS fields are 6, 10 and 100Jy/beam, respectively.
X-ray AGN (XrayAGN) are selected using the Szokoly et al.
(2004, Cat. J/ApJS/155/271) classification:
Lx≥1041erg/s & HR>-0.2
Lx≥1102erg/s & HR≤-0.2
The on-axis limiting X-ray flux in the soft and hard bands for the CDFS,
COSMOS and UDS fields are 9.110-18 and 5.5x10-17erg/cm2/s,
1.9x10-16 and 7.3x10-16erg/cm2/s, and
6.0x10-16 and 3.0x10-15erg/cm2/s, respectively.
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Acknowledgements:
Michael Cowley, michael.cowley(at)hdr.mq.edu.au
(End) Patricia Vannier [CDS] 01-Mar-2017