J/ApJ/929/108 MALS SALT-NOT survey of MIR-selected AGN at z<3.5 (Gupta+, 2022)
MALS SALT-NOT survey of MIR-selected powerful radio-bright AGN at 0<z<3.5.
Gupta N., Shukla G., Srianand R., Krogager J.-K., Noterdaeme P.,
Baker A.J., Combes F., Fynbo J.P.U., Momjian E., Hilton M., Hussain T.,
Moodley K., Petitjean P., Chen H.-W., Deka P., Dutta R., Jose J.,
Jozsa G.I.G., Kaski C., Klockner H.-R., Knowles K., Sikhosana S.,
Wagenveld J.
<Astrophys. J., 929, 108 (2022)>
=2022ApJ...929..108G 2022ApJ...929..108G
ADC_Keywords: Active gal. nuclei; QSOs; Spectra, optical; Redshifts;
Radio sources; Photometry, infrared; Photometry, ugriz;
Cross identifications; Surveys
Keywords: Active galactic nuclei ; Quasars ; Broad-absorption line quasar ;
Blazars
Abstract:
We present results of an optical spectroscopic survey using SALT and
the Nordic Optical Telescope to build a Wide-field Infrared Survey
Explorer mid-infrared color-based, dust-unbiased sample of powerful
radio-bright (>200mJy at 1.4GHz) active galactic nuclei (AGN) for the
MeerKAT Absorption Line Survey (MALS). Our sample has 250 AGN (median
z=1.8) showing emission lines, 26 with no emission lines, and
27 without optical counterparts. Overall, our sample is fainter
(Δi=0.6mag) and redder (Δ(g-i)=0.2mag) than radio-selected
quasars, and representative of fainter quasar population detected in
optical surveys. About 20% of the sources are narrow-line AGN
(NLAGN)-65% of these, at z<0.5 are galaxies without strong nuclear
emission, and 10% at z>1.9, have emission line ratios similar to radio
galaxies. The farthest NLAGN in our sample is M1513-2524
(zem=3.132), and the largest radio source (size ∼330kpc) is
M0909-3133 (zem=0.884). We discuss in detail 110 AGN at 1.9<z<3.5.
Despite representing the radio loudest quasars (median R=3685), their
Eddington ratios are similar to the Sloan Digital Sky Survey quasars
having lower R. We detect four CIV broad-absorption line (BAL) QSOs,
all among AGN with least R, and highest black hole masses and
Eddington ratios. The BAL detection rate (4-2+3%) is consistent
with that seen in extremely powerful (L1.4GHz>1025W/Hz) quasars.
Using optical light curves, radio polarization, and γ-ray
detections, we identify seven high-probability BL Lacertae objects. We
also summarize the full MALS footprint to search for HI 21cm and OH
18cm lines at z<2.
Description:
We observed 255 and 99 WISE radio-bright AGN with the Southern African
Large Telescope (SALT) and the Nordic Optical Telescope (NOT),
respectively. Of these, 40 targets, are common to both the sub-surveys.
The details for NOT observations carried out in 2016 August (P53-012)
and 2017 February (P54-005; PI: Krogager) are presented by
Krogager+ 2018ApJS..235...10K 2018ApJS..235...10K
We used the Robert Stobie Spectrograph (RSS) on SALT to obtain optical
spectra of 255 targets. These service mode observations were carried
out between 2014 November and 2017 April through the programs:
2014-2-SCI-027, 2015-1-SCI-012, 2015-2-SCI-030, 2016-1-SCI-022, and
2016-2-SCI-17 (PI: N. Gupta). We used RSS PG0900 grating to obtain a
wavelength coverage of 4486-7533Å, but with gaps at 5497-5551 and
6542-6589Å. The resulting spectral resolution is R=1064 at 6041Å.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 226 303 *Sample of radio sources for the uGMRT survey
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Note on table1.dat: List of targets excluded from the NOT sample presented
in Table 1 of Krogager+ (2018ApJS..235...10K 2018ApJS..235...10K): M024944.50+123706.3,
M051938.34+174641.2, M163906.46+114409.2, M162303.03+123958.4,
M060012.92-071037.9, M162539.34-041616.3 and M172423.07+032632.5
(see also Section 2.2).
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See also:
VIII/65 : 1.4GHz NRAO VLA Sky Survey (NVSS) (Condon+ 1998)
VIII/78 : Sydney University Molonglo Sky Survey (SUMSS) (Mauch+ 2006)
VIII/81 : Sydney University Molonglo Sky Survey (SUMSS V2.1) (Mauch+ 2008)
II/328 : AllWISE Data Release (Cutri+ 2013)
J/MNRAS/354/L31 : SDSS DR2 QSO and DLA properties (Murphy+, 2004)
J/ApJS/166/470 : SDSS-Spitzer type I QSOs IR photometry (Richards+, 2006)
J/ApJ/666/806 : SED of Spitzer quasars (QUEST) (Netzer+, 2007)
J/ApJ/658/815 : Radio loudness of active galactic nuclei (Sikora+, 2007)
J/A+A/495/691 : Multifreq. catalogue of blazars, Roma-BZCAT (Massaro+, 2009)
J/A+A/505/1087 : DLAs in SDSS-DR7 (Noterdaeme+, 2009)
J/ApJ/702/1230 : Rotation measure image of the sky (Taylor+, 2009)
J/ApJ/713/970 : Low-resolution SED templates for AGNs & gal. (Assef+, 2010)
J/ApJ/708/427 : Type 2 AGNs with double-peaked [OIII] lines (Liu+, 2010)
J/ApJS/194/45 : QSO properties from SDSS-DR7 (Shen+, 2011)
J/ApJS/218/23 : Fermi LAT third source catalog (3FGL) (Acero+, 2015)
J/A+A/598/A17 : The 2WHSP catalog (Chang+, 2017)
J/ApJS/234/23 : The WISE AGN candidates catalogs (Assef+, 2018)
J/ApJS/242/4 : Two new catalogs of blazar candidates (D'Abrusco+, 2019)
J/ApJ/922/179 : Host galaxies phot. for WISE-selected AGNs (Barrows+, 2021)
J/A+A/648/A116 : PKS 1830-211 OH and HI spectra (Combes+, 2021)
J/ApJS/255/28 : ∼420MHz uGMRT obs. of MIR radio-loud AGN (Gupta+, 2021)
J/A+A/673/A113 : MALS ten pointings continuum catalogue (Wagenveld+ 2023)
J/ApJS/270/33 : MALS DR1 v2 (Deka+ 2024)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1 A1 --- Type Code (1)
3- 21 A19 --- Name NVSS catalog identifier (MHHMMSS.ss+DDMMSS.s) (2)
24 A1 --- f_Name Flag on Name (3)
26- 31 F6.1 mJy Flux [200.4/4093] NVSS 20cm flux density
33 A1 --- l_Bmaj Limit flag on Bmaj
34- 37 F4.1 arcsec Bmaj [13.9/50] NVSS deconvolved radio source major
axis
39 A1 --- l_Bmin Limit flag on Bmin
40- 43 F4.1 arcsec Bmin [13.9/20] NVSS deconvolved radio source minor
axis
45- 49 F5.1 deg BPA [-88.6/89.5]? NVSS deconvolved radio source
position angle
51- 56 F6.4 --- z [0.1/5.1]? Spectroscopic redshift from SALT-NOT
spectra
58- 62 A5 --- Tel Telescope use for spectroscopy (4)
64 A1 --- AGN AGN type (5)
66- 84 A19 --- WISEA WISE source identifier (JHHMMSS.ss+DDMMSS.s)
86- 96 F11.7 deg RAdeg WISE Right Ascension (J2000)
98- 108 F11.7 deg DEdeg [-40.2/20] WISE Declination (J2000)
110- 114 F5.2 mag W1mag [13.2/18] WISE 3.4 micron band magnitude
116- 119 F4.2 mag e_W1mag [0.03/0.3] Uncertainty in W1mag
121- 125 F5.2 mag W2mag [12.2/16.8] WISE 4.6 micron band magnitude
127- 131 F5.3 mag e_W2mag [0.02/0.4]? Uncertainty in W2mag
133- 137 F5.2 mag W3mag [8.2/13] WISE 12 micron band magnitude
139- 143 F5.3 mag e_W3mag [0.02/0.6]? Uncertainty in W3mag
145- 147 A3 --- --- [PSO]
149- 165 A17 --- PSO PanSTARRS1 identifier (JDDD.dddd+DD.dddd)
167- 168 I2 --- Nsdet [0/67]? Number of stacked detections
170- 171 I2 --- Ndet [0/97]? Number of single epoch detections in
all filters
173- 177 F5.2 mag gmag [18/25.7]? PS1 g band AB magnitude
179- 182 F4.2 mag e_gmag [0/1.7]? Uncertainty in gmag (6)
184- 188 F5.2 mag rmag [17.8/25.2]? PS1 r band AB magnitude
190- 193 F4.2 mag e_rmag [0/1.2]? Uncertainty in rmag (6)
195- 199 F5.2 mag imag [17.5/23.7]? PS1 i band AB magnitude
201- 204 F4.2 mag e_imag [0/0.4]? Uncertainty in imag (6)
206- 210 F5.2 mag zmag [17.4/23.6]? PS1 z band AB magnitude
212- 215 F4.2 mag e_zmag [0/0.7]? Uncertainty in zmag (6)
217- 221 F5.2 mag ymag [17.4/26]? PS1 y band AB magnitude
223- 226 F4.2 mag e_ymag [0/10]? Uncertainty in ymag (6)
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Note (1): Code as follows:
A = Spectra with optical emission lines (250 sources);
B = No optical emission lines (26 sources);
C = Dark fields (27 sources).
Note (2): NVSS ID based on RA & DEC (J2000); M stands for MALS SALT-NOT survey.
NVSS are named in Simbad
Note (3): Flag as follows:
a = z from single emission line assumed to be CIV;
b = z from single emission line assumed to be CIII;
c = z from single emission line assumed to be MgII;
d = z from single emission line assumed to be [OII];
f = z from single emission line assumed to be Lyα.
Note (4): Telescope as follows:
SALT = Southern African Large Telescope (215 occurrences)
NOT = Nordic Optical Telescope (48 occurrences)
SUGAR = Observed with both SALT and NOT (40 occurrences)
Note (5): AGN type as follows:
G = narrow line AGN (51 occurrences);
Q = broad line AGN (199 occurrences).
Note (6): Errors from PS1-mean for sources with redshifts and
emission line less sources, and PS1-stack for dark fields.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 07-Mar-2024