J/ApJS/265/29 PS1 z>5.6 QSO Survey. II. 55 quasars follow-up (Banados+, 2023)
The Pan-STARRS1 z>5.6 Quasar Survey.
II. Discovery of 55 quasars at 5.6<z<6.5
Banados E., Schindler J.-T., Venemans B.P., Connor T., Decarli R.,
Farina E.P., Mazzucchelli C., Meyer R.A., Stern D., Walter F., Fan X.,
Hennawi J.F., Khusanova Y., Morrell N., Nanni R., Noirot G., Pensabene A.,
Rix H.-W., Simon J., Verdoes Kleijn G.A., Xie Z.-L., Yang D.-M.,
Connor A.
<Astrophys. J. Suppl. Ser., 265, 29 (2023)>
=2023ApJS..265...29B 2023ApJS..265...29B
ADC_Keywords: QSOs; Spectra, optical; Redshifts; Photometry, ugriz; Surveys
Keywords: Quasars ; Active galactic nuclei
Abstract:
The identification of bright quasars at z≳6 enables detailed studies
of supermassive black holes, massive galaxies, structure formation,
and the state of the intergalactic medium within the first billion
years after the Big Bang. We present the spectroscopic confirmation of
55 quasars at redshifts 5.6<z<6.5 and UV magnitudes -24.5<M1450<-28.5
identified in the optical Pan-STARRS1 and near-IR VIKING surveys
(48 and 7, respectively). Five of these quasars have independently
been discovered in other studies. The quasar sample shows an extensive
range of physical properties, including 17 objects with weak emission
lines, 10 broad absorption line quasars, and 5 objects with strong
radio emission (radio-loud quasars). There are also a few notable
sources in the sample, including a blazar candidate at z=6.23, a
likely gravitationally lensed quasar at z=6.41, and a z=5.84 quasar in
the outskirts of the nearby (D∼3Mpc) spiral galaxy M81. The blazar
candidate remains undetected in NOEMA observations of the [CII] and
underlying emission, implying a star formation rate <30-70M☉/yr.
A significant fraction of the quasars presented here lies at the
foundation of the first measurement of the z∼6 quasar luminosity
function from Pan-STARRS1 (introduced in a companion paper). These
quasars will enable further studies of the high-redshift quasar
population with current and future facilities.
Description:
In Table 3 we report follow-up photometry, spanning 2013-09-28 to
2020-11-20, for our quasar candidates obtained in the following
filters and telescopes: I#705 (IE) and Z#623 (ZE) with the ESO
Faint Object Spectrograph and Camera (EFOSC2) at the NTT telescope in
La Silla, JG and HG with the GROND camera at the MPG 2.2m
telescope in La Silla, Js Hs Ks with SOFI at the NTT telescope in
La Silla, and YR with the RetroCam camera at the Du Pont telescope in
Las Campanas Observatory. For completeness, in Table 3 we also report
IZYHK magnitudes from public surveys or published papers when
available. See Section 2.3.
The discovery of the 55 quasars presented in this work has been a
large effort, involving multiple observatories in the time frame
2013-11-19 to 2022-09-28. A few of these quasars have been part of
multiple follow-up campaigns, and some of their properties have been
presented in the literature; see Section 3.3.
The spectrographs/telescopes used for the discovery of these quasars
are the Double Spectrograph (DBSP) on the 200 inch (5m) Hale telescope
at Palomar Observatory (P200), the Low Dispersion Survey Spectrograph
(LDSS3) at the Clay Magellan telescope at Las Campanas Observatory,
the Multi-Object Double Spectrograph (MODS) at the Large Binocular
Telescope (LBT), EFOSC2 at the NTT telescope in La Silla, the Low
Resolution Imaging Spectrometer (LRIS) at the Keck telescope on
Maunakea, the Gemini Multi-Object Spectrographs (GMOS) on the
Gemini-North telescope, the Red Channel Spectrograph on the 6.5m MMT
Telescope, and the FOcal Reducer/low dispersion Spectrograph 2 (FORS2)
at the Very Large Telescope (VLT). The spectroscopic observations log
is listed in Table 1.
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 78 63 Discovery spectroscopic observations of the new
quasars presented in this work
table2.dat 129 55 Properties of the quasars discovered in this work,
sorted by RA
table3.dat 152 55 Photometry of the quasars discovered in this work,
sorted by RA
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See also:
II/319 : UKIDSS-DR9 LAS, GCS and DXS Surveys (Lawrence+ 2012)
II/359 : The VISTA Hemisphere Survey (VHS) catalog DR4.1 (McMahon+, 2013)
II/343 : VIKING catalogue data release 2 (Edge+, 2016)
I/337 : Gaia DR1 (Gaia Collaboration, 2016)
II/347 : KiDS-ESO-DR3 multi-band source catalog (de Jong+, 2017)
II/367 : The VISTA Hemisphere Survey (VHS) catalog DR5 (McMahon+, 2020)
II/371 : The Dark Energy Survey (DES): Data Release 2 (Abbott+, 2021)
VII/292 : DESI Legacy Imaging Surveys DR8 (Duncan, 2022)
J/ApJS/227/11 : PS1 z>5.6 quasars follow-up (Banados+, 2016)
J/ApJ/818/105 : CNSS pilot survey (Mooley+, 2016)
J/A+A/585/A87 : Quasar composite made from bright QSOs (Selsing+, 2016)
J/A+A/598/A78 : The GMRT 150MHz all-sky radio survey (Intema+, 2017)
J/ApJ/887/196 : REQUIEM survey. I. Lyα halos around QSOs (Farina+, 2019)
J/MNRAS/487/3305 : Broad-line velocity shifts in 1.5<z<7.5 QSOs (Meyer+, 2019)
J/ApJ/873/35 : Gemini GNIRS NIR sp. of 50 QSOs at z≳5.7 (Shen+, 2019)
J/A+A/624/A13 : KiDS DR3 QSO catalog (Nakoneczny+, 2019)
J/A+A/630/A83 : 4.85 & 10.45GHz fluxes of SDSS-FIRST sources (Zajacek+, 2019)
J/ApJ/905/51 : X-SHOOTER/ALMA QSOs at 5.78<z<7.54. I. NIR (Schindler+, 2020)
J/A+A/656/A137 : 144MHz radio fluxes of z>5 quasars (Gloudemans+, 2021)
J/other/PASA/38.58 : Rapid ASKAP Continuum Survey. II. RACS cat. (Hale+, 2021)
J/A+A/668/A27 : 24 new radio-bright quasars spectra (Gloudemans+, 2022)
J/ApJS/259/18 : SHELLQs. XVI. New quasars at 5.8<z<7 (Matsuoka+, 2022)
J/A+A/667/A9 : Unveiling warm dense ISM phase in z>6 QSOs (Pensabene+, 2022)
J/A+A/659/A1 : LOFAR Two-metre Sky Survey (LoTSS) DR2 (Shimwell+, 2022)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 21 A21 --- QSO PSO designation (PSO JDDD.dddd+DD.dddd) or
VIKING designation (VIK JHHMM+DDMM)
23- 33 A11 "Y/M/D" Date Observation date (UT)
34 A1 --- --- [-]
35- 36 I2 d Day2 ? Second day of observation
38- 52 A15 --- Inst Telescope / Instrument
54- 57 I4 s Exp [300/9000] Exposure time
59- 65 A7 arcsec Slit Slit width
67 A1 --- QLF? True or False
69- 78 A10 --- ID Quasar abbreviated identifier
(PDDD+DD or JHHMM+DDMM) as in other tables;
column added by CDS
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- ID Quasar abbreviated identifier
(PDDD+DD or JHHMM+DDMM)
12- 13 I2 h RAh Hour of Right Ascension (J2000)
15- 16 I2 min RAm Minute of Right Ascension (J2000)
18- 22 F5.2 s RAs Second of Right Ascension (J2000)
24- 24 A1 --- DE- Sign of the Declination (J2000)
25- 26 I2 deg DEd Degree of Declination (J2000)
28- 29 I2 arcmin DEm Arcminute of Declination (J2000)
31- 35 F5.2 arcsec DEs Arcsecond of Declination (J2000)
37- 42 F6.4 --- z [5.6/6.41] Spectroscopic redshift
44- 53 A10 --- n_z Method of determining z (1)
55- 55 I1 --- r_z [1/4] Reference for z (2)
57- 61 F5.2 mag 1450mag [18.7/21.8] Apparent rest-frame 1450Å
magnitude
63- 68 F6.2 mag 1450Mag [-28/-24.8] Absolute rest-frame 1450Å
magnitude
70- 74 F5.2 mag 2500mag [19.4/22.41] Apparent rest-frame 2500Å
magnitude
76- 89 A14 --- Best Best template identifier
91-101 A11 --- Note Additional note(s)
103-129 A27 --- Name Quasar name as in Table 1 and in VIKING+KiDS
catalogs; column added by CDS
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Note (1): Method as follows:
template = quasar template. The typical redshift uncertainties
is <0.03 (see Section 3.2).
[CII] = redshift from the [CII] line (5 occurrences)
absorption = For "P173+48", we use an absorption feature to determine
the redshift (see Section 3.8).
Note (2): Reference as follows:
1 = This work
2 = Decarli et al. (2018ApJ...854...97D 2018ApJ...854...97D)
3 = Eilers et al. (2020ApJ...900...37E 2020ApJ...900...37E)
4 = Venemans et al. (2020ApJ...904..130V 2020ApJ...904..130V)
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Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- ID Quasar abbreviated identifier
(PDDD+DD or JHHMM+DDMM)
12 A1 --- l_gP1mag The 3σ limit flag on gP1mag
14- 18 F5.2 mag gP1mag [22.5/24.24]? Pan-STARRS1 g band magnitude (3)
20 A1 --- l_rP1mag The 3σ limit flag on rP1mag
22- 26 F5.2 mag rP1mag [22.73/24.03]? Pan-STARRS1 r band magnitude (3)
28- 31 F4.2 mag e_rP1mag [0.19/0.31]? Uncertainty in rP1mag
33 A1 --- l_iP1mag The 3σ limit flag on iP1mag
35- 39 F5.2 mag iP1mag [21.87/24.5] Pan-STARRS1 i band magnitude (3)
41- 44 F4.2 mag e_iP1mag [0.06/0.35]? Uncertainty in iP1mag
46- 50 F5.2 mag zP1mag [19.57/21.59]? Pan-STARRS1 z band magnitude (3)
52- 55 F4.2 mag e_zP1mag [0.02/0.18]? Uncertainty in zP1mag
57- 61 F5.2 mag yP1mag [19.28/21.81]? Pan-STARRS1 y band magnitude (3)
63- 66 F4.2 mag e_yP1mag [0.04/0.29]? Uncertainty in yP1mag
68 A1 --- l_Imag The 3σ limit flag on Imag
70- 74 F5.2 mag Imag [21.53/24.41]? The I band magnitude
76- 79 F4.2 mag e_Imag [0.03/0.36]? Uncertainty in Imag
81- 82 I2 --- r_Imag [1/19]? Telescope reference source for Imag (4)
84- 88 F5.2 mag Zmag [19.9/22.12]? The Z band magnitude
90- 93 F4.2 mag e_Zmag [0.01/0.14]? Uncertainty in Zmag
95- 96 I2 --- r_Zmag [6/23]? Telescope reference source for Zmag (4)
98-102 F5.2 mag Ymag [19.28/21.79]? The Y band magnitude
104-107 F4.2 mag e_Ymag [0.03/0.26]? Uncertainty in Ymag
109-110 I2 --- r_Ymag [16/25]? Telescope reference source for Ymag (4)
112-116 F5.2 --- Jmag [19.23/21.94]? The J band magnitude
118-121 F4.2 --- e_Jmag [0.03/0.33]? Uncertainty in Jmag
123-124 I2 --- r_Jmag [9/25]? Telescope reference source for Jmag (4)
126-130 F5.2 --- Hmag [19.02/21.53]? The H band magnitude
132-135 F4.2 --- e_Hmag [0.05/0.35]? Uncertainty in Hmag
137-138 I2 --- r_Hmag [10/25]? Telescope reference source for Hmag (4)
140-144 F5.2 --- Kmag [18.68/21.29]? The K band magnitude
146-149 F4.2 --- e_Kmag [0.03/0.3]? Uncertainty in Kmag
151-152 I2 --- r_Kmag [13/25]? Telescope reference source for Kmag (4)
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Note (3): The PS1 magnitudes are dereddened. Reddened magnitudes can be
obtained by adding λf*E(B-V) with
λf=(3.172, 2.271, 1.682, 1.322, 1.087) for (gP1mag, rP1mag,
iP1mag, zP1mag, yP1mag), see Schlafly & Finkbeiner (2011ApJ...737..103S 2011ApJ...737..103S).
For the VIKING quasars, the magnitudes reported in the iP1mag column
are actually i magnitudes from the KiDS survey.
Note (4): Instrument and observation date (YYYY-MM-DD) or survey identifier
as follows:
1 = EFOSC2 2013-09-28;
2 = EFOSC2 2014-03-03;
3 = EFOSC2 2014-07-24;
4 = EFOSC2 2014-07-27;
5 = EFOSC2 2015-07-22;
6 = EFOSC2 2016-09-13;
7 = EFOSC2 2016-09-14;
8 = EFOSC2 2018-06-26;
9 = GROND 2016-09-22;
10 = GROND 2017-01-01;
11 = SOFI 2017-05-29;
12 = SOFI 2018-06-26;
13 = SOFI 2019-12-13;
14 = SOFI 2019-12-14;
15 = SOFI 2020-11-20;
16 = Retrocam 2016-09-20;
17 = DES DR2 (Cat. II/371)
18 = DELS DR9 (see VII/292)
19 = KiDS (see II/347)
20 = UKIRT Hemisphere Survey (UHS)
21 = UKIDSS (see II/319)
22 = VHS (see II/367)
23 = VIKING (see II/343)
24 = Bischetti et al. (2022Natur.605..244B 2022Natur.605..244B)
25 = Ross et al. (2020MNRAS.494..789R 2020MNRAS.494..789R)
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History:
From electronic version of the journal
References:
Banados et al. Paper I. 2016ApJS..227...11B 2016ApJS..227...11B Cat. J/ApJS/227/11
Schindler et al. Paper III. 2023ApJ...943...67S 2023ApJ...943...67S Cat. J/ApJ/943/67
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 04-May-2023