J/MNRAS/478/3721 Deep ALMA photometry of distant X-ray AGN (Stanley+, 2018)
Deep ALMA photometry of distant X-ray AGN:
improvements in star formation rate constraints, and AGN identification.
Stanley F., Harrison C.M., Alexander D.M., Simpson J., Knudsen K.K.,
Mullaney J.R., Rosario D.J., Scholtz J.
<Mon. Not. R. Astron. Soc., 478, 3721-3739 (2018)>
=2018MNRAS.478.3721S 2018MNRAS.478.3721S (SIMBAD/NED BibCode)
ADC_Keywords: Active gal. nuclei ; X-ray sources ; Infrared sources
Keywords: galaxies: active - galaxies: evolution - galaxies: star formation
Abstract:
We present the star formation rates (SFRs) of a sample of 109 galaxies
with X-ray-selected active galactic nuclei (AGNs) with moderate to
high X-ray luminosities (L2-8keV=1042-1045erg/s), at redshifts
1<z<4.7, that were selected to be faint or undetected in the Herschel
bands. We combine our deep Atacama large (sub-)millimetre array (ALMA)
continuum observations with deblended 8-500um photometry from Spitzer
and Herschel, and use infrared (IR) spectral energy distribution (SED)
fitting and AGN - star formation decomposition methods. The addition
of the ALMA photometry results in an order of magnitude more X-ray AGN
in our sample with a measured SFR (now 37%). The remaining 63 % of the
sources have SFR upper limits that are typically a factor of 2-10
times lower than the pre-ALMA constraints. With the improved
constraints on the IR SEDs, we can now identify a mid-IR (MIR) AGN
component in 50% of our sample, compared to only ∼1% previously. We
further explore the F870um/F24um -redshift plane as a tool for the
identification of MIR-emitting AGN, for three different samples
representing AGN-dominated, star formation-dominated, and composite
sources. We demonstrate that the F870um/F24um -redshift plane can
successfully split between AGN and star formation-dominated sources,
and can be used as an AGN identification method.
Description:
We present a sample of X-ray selected AGN that have been observed in
two ALMA Band-7 programs during Cycle 1 and Cycle 2. Our ALMA Band-7
programs were designed with a key aim of constraining the SFR and sSFR
distributions of a sample of X-ray AGN covering moderate to high X-ray
luminosities, in the redshift range where we observe the peak of star
formation and AGN activities.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 57 55 Properties of the ALMA observed X-ray sample
in the GOODS-S field
tablea2.dat 57 54 Properties of the ALMA observed X-ray sample
in the COMSOS field
tablea3.dat 50 41 SED-fitting results for the comparison sample
of WISE AGN-dominated sources
tablea4.dat 52 112 SED-fitting results for the comparison sample
of star formation galaxies
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See also:
J/ApJS/195/10 : The CDF-S survey: 4Ms source catalogs (Xue+, 2011)
J/ApJS/201/30 : The Chandra COSMOS survey. III. (Civano+, 2012)
J/ApJ/813/45 : ALMA observations in z∼0.5-3 quasars (Lonsdale+, 2015)
J/ApJ/768/91 : ALMA observations of LESS submm galaxies (Hodge+, 2013)
Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 A2 --- Field [GS] Field
4- 6 I3 --- XID X-ray ID of the source in the Xue et al.
(2011, Cat. J/ApJS/195/10) catalogue,
[XLB2011] NNN in Simbad
8- 12 F5.3 --- z Redshift of the source from Hsu et al.
(2014, Cat. J/ApJ/796/60)
14- 21 E8.3 10-7W L2-8keV X-ray HB luminosity of the source (in erg/s)
23 A1 --- l_LIR-SF Limit flag on LIR-SF
24- 27 F4.2 10+38W LIR-SF IR luminosity due to star formation derived
by the best-fitting SED solution
(in 1045erg/s)
29- 32 F4.2 10+38W E_LIR-SF ? Error on LIR-SF (upper value)
34- 37 F4.2 10+38W e_LIR-SF ? Error on LIR-SF (lower value)
39 A1 --- l_LIR-AGN Limit flag on LIR-AGN
40- 44 F5.2 10+38W LIR-AGN ?=- IR luminosity due to the AGN derived from
the the best-fitting SED solution
(in 1045erg/s)
46- 49 F4.2 10+38W E_LIR-AGN ? Error on LIR-AGN (upper value)
51- 54 F4.2 10+38W e_LIR-AGN ? Error on LIR-AGN (lower value)
56- 57 I2 --- AGN Flag for the AGN component of the fits (G1)
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Byte-by-byte Description of file: tablea2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1 A1 --- Field [C] Field
3- 6 I4 --- XID X-ray ID of the source in the Civano et al.
(2012, Cat J/ApJS/201/30) catalogue,
[ECV2009] NNNN in Simbad
8- 12 F5.3 --- z Redshift of the source from Marchesi et al.
(2016. Cat. J/ApJ/817/34)
14- 21 E8.3 10-7W L2-8keV 2-10keV luminosity of the source (in erg/s)
23 A1 --- l_LIR-SF Limit flag on LIR-SF
24- 27 F4.2 10+38W LIR-SF IR luminosity due to star formation derived
by the best-fitting SED solution
(in 1045 erg/s)
29- 32 F4.2 10+38W E_LIR-SF ? Error on LIR-SF (upper value)
34- 37 F4.2 10+38W e_LIR-SF ? Error on LIR-SF (lower value)
39 A1 --- l_LIR-AGN Limit flag on LIR-AGN
40- 44 F5.2 10+38W LIR-AGN ?=- IR luminosity due to the AGN derived from
the the best-fitting SED solution
(in 1045 erg/s)
46- 49 F4.2 10+38W E_LIR-AGN ? Error on LIR-AGN (upper value)
51- 54 F4.2 10+38W e_LIR-AGN ? Error on LIR-AGN (lower value)
56- 57 I2 --- AGN Flag for the AGN component of the fits (G1)
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Byte-by-byte Description of file: tablea3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- WISE WISE ID of the source as given in Lonsdale et
al. (2015, Cat. J/ApJ/813/45), WHHMM+DDMM
12- 16 F5.3 --- z Redshift of the source from Lonsdale et al.
(2015, Cat. J/ApJ/813/45)
18 A1 --- l_LIR-SF Limit flag on LIR-SF
19- 22 F4.2 10+39W LIR-SF ?=- IR luminosity due to star formation
derived by the best-fitting SED solution
(in 1046erg/s)
24- 27 F4.2 10+39W E_LIR-SF ? Error on LIR-SF (upper value)
29- 32 F4.2 10+39W e_LIR-SF ? Error on LIR-SF (lower value)
34- 38 F5.2 10+39W LIR-AGN IR luminosity due to the AGN derived from the
best-fitting SED solution (in 1046 erg/s)
40- 43 F4.2 10+39W E_LIR-AGN ? Error on LIR-AGN (upper value)
45- 48 F4.2 10+39W e_LIR-AGN ? Error on LIR-AGN (lower value)
50 I1 --- AGN Flag for the AGN component of the fits (G1)
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Byte-by-byte Description of file: tablea4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 12 A12 --- A-LESS A-LESS ID of the source as given in Hodge et
al. (2013, Cat. J/ApJ/768/91), A-LESS NNN.N,
[HKS2013] ALESS NNN.N in Simbad
14- 18 F5.3 --- z Redshift of the source from Simpson et al.
(2014, Cat. J/ApJ/788/125) and
Danielson et al. (2017, Cat. J/ApJ/840/78)
20- 23 F4.2 10+39W LIR-SF IR luminosity due to star formation derived
by the best-fitting SED solution
(in 1046 erg/s)
25- 28 F4.2 10+39W E_LIR-SF Error on LIR-SF (upper value)
30- 33 F4.2 10+39W e_LIR-SF Error on LIR-SF (lower value)
35- 39 F5.2 10+38W LIR-AGN ?=- IR luminosity due to the AGN derived from
the best-fitting SED solution
(in 1045 erg/s)
41- 45 F5.2 10+38W E_LIR-AGN ? Error on LIR-AGN (upper value)
47- 50 F4.2 10+38W e_LIR-AGN ? Error on LIR-AGN (lower value)
52 I1 --- AGN Flag for the AGN component of the fits (G1)
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Global notes:
Note (G1): Flag for the AGN component of the fits as follows:
-1 = only upper limit constraints
0 = SED fit does not require an AGN component
1 = SED fit requires an AGN component, but has a weak contribution and
is uncertain (<20% of the IR luminosity)
2 = SED fit requires an AGN component with significant contribution
(≥20% of the IR luminosity)
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 25-Aug-2021