J/ApJS/250/26 Spectroscopic follow-up of the QUBRICS quasars (Boutsia+, 2020)
The spectroscopic follow-up of the QUBRICS BRIght quasar survey.
Boutsia K., Grazian A., Calderone G., Cristiani S., Cupani G., Guarneri F.,
Fontanot F., Amorin R., D'Odorico V., Giallongo E., Salvato M., Omizzolo A.,
Romano M., Menci N.
<Astrophys. J. Suppl. Ser., 250, 26 (2020)>
=2020ApJS..250...26B 2020ApJS..250...26B
ADC_Keywords: QSOs; Spectra, optical; Redshifts; Photometry, RI;
Active gal. nuclei; Surveys
Keywords: Cosmology ; Quasars ; Catalogs ; Redshift surveys ; Surveys ;
Active galaxies
Abstract:
We present the results of the spectroscopic follow-up of the QUasars
as BRIght beacons for Cosmology in the Southern Hemisphere (QUBRICS;
Calderone+ 2019, J/ApJ/887/268) survey. The selection method is based
on a machine-learning approach applied to photometric catalogs,
covering an area of ∼12400deg2 in the Southern Hemisphere. The
spectroscopic observations started in 2018 and identified 55 new,
high-redshift (z≥2.5), bright (i≤18) quasi-stellar objects (QSOs),
with the catalog published in late 2019. Here we report the current
status of the survey, bringing the total number of bright QSOs at
z≥2.5 identified by QUBRICS to 224. The success rate of the QUBRICS
selection method, in its most recent training, is estimated to be 68%.
The predominant contaminant turns out to be lower-z QSOs at z<2.5.
This survey provides a unique sample of bright QSOs at high z
available for a number of cosmological investigations. In particular,
carrying out the redshift drift measurements (Sandage Test) in the
Southern Hemisphere, using the High Resolution Spectrograph at the 39m
Extremely Large Telescope appears to be possible with less than 2500hr
of observations spread over 30 targets in 25yr.
Description:
The QUasars as BRIght beacons for Cosmology in the Southern Hemisphere
(QUBRICS) pilot campaign has been presented in Paper I
(Calderone+ 2019, J/ApJ/887/268). Observations have been obtained
using various instruments at Las Campanas Observatory (LCO), and the
New Technology Telescope of the European Southern Observatory
(ESO-NTT) telescope at La Silla.
Between 2019 August and 2020 February, we have been awarded more
nights at these facilities with the Wide Field CCD (WFCCD) camera at
duPont telescope (see Section 3.1), the Low Dispersion Survey
Spectrograph (LDSS-3) at the Clay telescope (see Section 3.2) and with
the ESO Faint Object Spectrograph and Camera (EFOSC2) at NTT (see
Section 3.3) in order to expand our spectroscopic survey.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 82 303 All observed sources with secure redshift
identification
table2.dat 56 24 Additional identifications from the literature
table3.dat 85 30 The Golden sample of Southern QSOs
for the Sandage Test
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See also:
II/335 : Revised cat. of GALEX UV sources (GUVcat_AIS GR6+7) (Bianchi+ 2017)
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
II/358 : SkyMapper Southern Sky Survey. DR1.1 (Wolf+, 2018)
VII/250 : The 2dF Galaxy Redshift Survey (2dFGRS) (2dFGRS Team, 1998-2003)
VII/259 : 6dF galaxy survey final redshift release (Jones+, 2009)
VII/258 : Quasars and Active Galactic Nuclei (13th Ed.) (Veron+ 2010)
VII/286 : SDSS quasar catalog, fourteenth data release (Paris+, 2018)
J/AJ/144/49 : Quasars from SDSS-DR7, WISE and UKIDSS surveys (Wu+, 2012)
J/MNRAS/445/1745 : Giant Gemini GMOS survey. I. (Worseck+, 2014)
J/ApJ/819/24 : z>4.5 QSOs with SDSS and WISE. I. Opt. spectra (Wang+, 2016)
J/MNRAS/465/4914 : R-band light curves of HE 0435-1223 (Bonvin+, 2017)
J/AJ/153/107 : Australian Dark Energy Survey (OzDES) QSO cat. (Tie+, 2017)
J/ApJS/243/5 : The ELQS in the PS1 footprint (PS-ELQS) (Schindler+, 2019)
J/ApJ/871/258 : ELQS in SDSS. III. Full ELQS quasar cat. (Schindler+, 2019)
J/ApJ/887/268 : QSOs in the Southern Hemisphere (QUBRICS) (Calderone+, 2019)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 I9 --- ID [107306/318699655] Skymapper identifier
11- 12 A2 --- f_ID Flag on ID (1)
14- 15 I2 h RAh Hour of Right Ascension (J2000)
17- 18 I2 min RAm Minute of Right Ascension (J2000)
20- 24 F5.2 s RAs Second of Right Ascension (J2000)
26 A1 --- DE- Sign of the Declination (J2000)
27- 28 I2 deg DEd Degree of Declination (J2000)
30- 31 I2 arcmin DEm Arcminute of Declination (J2000)
33- 37 F5.2 arcsec DEs Arcsecond of Declination (J2000)
39- 44 F6.3 mag imag [14.6/18.4] Apparent i band AB magnitude
46- 50 F5.3 --- zspec [0/4.8] Spectroscopic redshift
52- 55 A4 --- Class Class ("QSO": 251 occurrences; "AGN": 25
occurrences; "GAL": 9 occurrences or
"STAR": 18 occurrences)
57 A1 --- PapI Candidate in Paper I
(Calderone+ 2019ApJ...887..268C 2019ApJ...887..268C ;
yes: 259 occurrences) (2)
59 A1 --- New Candidate with new training set
(yes:205 occurrences) (2)
61- 64 I4 yr Obs.Y [2018/2020] Year of the observation
66- 67 I2 "month" Obs.M Month of the observation
68 A1 --- --- [/]
69- 70 I02 --- Obs2 ? Month for the second observation
72- 82 A11 --- Inst Instrument code(s) (3)
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Note (1): Flag as follows:
a = Independently discovered by Wolf et al. (2020MNRAS.491.1970W 2020MNRAS.491.1970W);
b = Included also in Schindler et al. (2019, J/ApJS/243/5);
c = Included also in Schindler et al. (2019, J/ApJ/871/258);
d = Independently discovered by Lucey et al. (2018MNRAS.476..927L 2018MNRAS.476..927L);
* = After updated reduction of PaperI (Calderone+ 2019ApJ...887..268C 2019ApJ...887..268C)
observed sources.
Note (2): Code as follows:
Y = Yes;
N = No;
- = Not part of the Main Sample (32 occurrences).
Note (3): Instrument code as follows:
IMACS = IMACS instrument on the Baade Magellan telescope (1 occurrence);
LDSS-3 = LDSS-3 instrument on the Clay Magellan telescope (42 occurrences);
FIRE = Folded-port InfraRed Echellete
on the Baade Magellan telescope (1 occurrence);
NTT = EFOSC2 on the ESO New Technology Telescope (NTT) telescope
(186 occurrences);
WFCCD = Wide Field CCD camera on the DuPont telescope (77 occurrences).
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Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 I9 --- ID [1459087/318330107] Skymapper identifier
11-12 I2 h RAh Hour of right ascension (J2000)
14-15 I2 min RAm Minute of right ascension (J2000)
17-21 F5.2 s RAs Second of right ascension (J2000)
23 A1 --- DE- Sign of declination (J2000)
24-25 I2 deg DEd Degree of declination (J2000)
27-28 I2 arcmin DEm Arcminute of declination (J2000)
30-33 F4.1 arcsec DEs Arcsecond of declination (J2000)
35-40 F6.3 mag imag [15.1/18] i-band AB magnitude
42-46 F5.3 --- zsp [0.2/3.13] Spectroscopic redshift
48-50 A3 --- Class Object class ("QSO" or "AGN")
52-56 A5 --- Survey Survey identifier (1)
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Note (1): Survey as follows:
6dF = Jones+, 2009, VII/259
OzDES = Australian Dark Energy Survey (Tie+, 2017, J/AJ/153/107)
UVES = Ultraviolet and Visual Echelle Spectrograph (UVES) spectrum
from GALEX (Bianchi+, 2017, II/335)
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1-19 A19 --- SMSS SkyMapper name of the source (JHHMMSS.ss+DDMMSS.s)
21-30 F10.6 deg RAdeg Right ascension (J2000)
32-41 F10.6 deg DEdeg [-69.4/-0.7] Declination (J2000)
43-48 F6.3 mag rmag [16.6/18.1]? r-band AB magnitude
49 A1 --- f_rmag [*] * : no value of rmag
51-56 F6.3 mag imag [16.3/17.5] i-band AB magnitude
58-64 F7.4 mag Gmag [16.5/18.6] Gaia G-band magnitude
66-70 F5.3 --- z [2.8/4.8] Redshift
72-75 F4.1 h t22.5 [39.9/99.4] Total time required to carry out
the Sandage Test (velocity accuracy of 22.5cm/s)
77-85 I9 --- ID [397340/318204033] Skymapper identifier
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History:
From electronic version of the journal
References:
Calderone et al. Paper I. 2019ApJ...887..268C 2019ApJ...887..268C Cat. J/ApJ/887/268
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 12-Nov-2020