J/ApJS/259/18 SHELLQs. XVI. New quasars at 5.8<z<7 (Matsuoka+, 2022)
Subaru High-z Exploration of Low-Luminosity Quasars (SHELLQs).
XVI. 69 new quasars at 5.8<z<7.0.
Matsuoka Y., Iwasawa K., Onoue M., Izumi T., Kashikawa N., Strauss M.A.,
Imanishi M., Nagao T., Akiyama M., Silverman J.D., Asami N., Bosch J.,
Furusawa H., Goto T., Gunn J.E., Harikane Y., Ikeda H., Ishimoto R.,
Kawaguchi T., Kato N., Kikuta S., Kohno K., Komiyama Y., Lee C.-H.,
Lupton R.H., Minezaki T., Miyazaki S., Murayama H., Nishizawa A.J.,
Oguri M., Ono Y., Ouchi M., Price P.A., Sameshima H., Sugiyama N.,
Tait P.J., Takada M., Takahashi A., Takata T., Tanaka M., Toba Y.,
Utsumi Y., Wang S.-Y., Yamashita T.
<Astrophys. J. Suppl. Ser., 259, 18-18 (2022)>
=2022ApJS..259...18M 2022ApJS..259...18M (SIMBAD/NED BibCode)
ADC_Keywords: QSOs; Redshifts; Photometry, ugriz; Spectra, optical;
Equivalent widths; Stars, brown dwarf; Spectral types
Keywords: Reionization; Quasars; Supermassive black holes;
High-redshift galaxies
Abstract:
We present the spectroscopic discovery of 69 quasars at 5.8<z<7.0,
drawn from the Hyper Suprime-Cam (HSC) Subaru Strategic Program (SSP)
imaging survey data. This is the 16th publication from the Subaru
High-z Exploration of Low-Luminosity Quasars (SHELLQs) project, and it
completes identification of all but the faintest candidates (i.e.,
i-band dropouts with zAB<24 and y-band detections, and z-band
dropouts with yAB<24) with Bayesian quasar probability PQB>0.1
in the HSC-SSP third public data release (PDR3). The sample reported
here also includes three quasars with PQB<0.1 at z∼6.6, which we
selected in an effort to completely cover the reddest point sources
with simple color cuts. The number of high-z quasars discovered in
SHELLQs has now grown to 162, including 23 type II quasar candidates.
This paper also presents identification of seven galaxies at
5.6<z<6.7, an [OIII] emitter at z=0.954, and 31 Galactic cool stars
and brown dwarfs. High-z quasars and galaxies compose 75% and 16%,
respectively, of all the spectroscopic SHELLQs objects that pass our
latest selection algorithm with the PDR3 photometry. That is, a total
of 91% of the objects lie at z>5.6. This demonstrates that the
algorithm has very high efficiency, even though we are probing an
unprecedentedly low luminosity population down to M1450~-21mag.
Description:
The Hyper Suprime-Cam (HSC) Subaru Strategic Program (SSP) candidates
were fed into follow-up spectroscopy programs at the 8.2m Subaru
Telescope and the 10.4m Gran Telescopio Canarias (GTC).
We use the Faint Object Camera and Spectrograph (FOCAS) on Subaru to
observe the wavelength range 0.75-1.0um with the VPH900 grism and 1.0"
slits, giving a spectral resolution of R∼1200 (Program ID: S18B-011I).
Similarly, the Optical System for Imaging and
low-intermediate-Resolution Integrated Spectroscopy (OSIRIS) on GTC is
used with the R2500I grism and 1.0" long slit, yielding spectra over
0.75-1.0um with R∼1500 (Program IDs: GTC5-20A, GTC10-20B, GTC42-21B).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 95 108 Journal of discovery spectroscopy
table2.dat 67 24 Objects detected in the near-IR bands
table3.dat 95 82 Spectroscopic properties
table4.dat 22 31 *Spectral classes of the Galactic dwarfs
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Note on table4.dat: We have identified 31 Galactic cool stars and brown dwarfs
with the present spectroscopy. Table 4 lists the rough spectral
classes, estimated by fitting the spectral standard templates of M4-
to T8-type dwarfs (Burgasser 2014ASInC..11....7B 2014ASInC..11....7B and
Skrzypek+ 2015A&A...574A..78S 2015A&A...574A..78S) to the observed spectra. We emphasize
that the stellar classifications are meant to be only approximate,
given the relatively poor data quality and limited spectral coverage.
See Section 3.
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See also:
J/ApJ/633/630 : Low-mass stars found in CFHTLS (Willott+, 2005)
J/MNRAS/435/3306 : Candidate type II QSOs in SDSS III (Alexandroff+, 2013)
J/ApJS/227/11 : PS1 z>5.6 quasars follow-up (Banados+, 2016)
J/PASJ/70/S10 : GOLDRUSH I. UV magnitudes (Ono+, 2018)
J/MNRAS/477/2817 : Luminous Lyα emitters at z∼2-3 (Sobral+, 2018)
J/A+A/643/A149 : J-PLUS Lyα-emitting candidates (Spinoso+, 2020)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 7 A7 --- Class Object type (1)
9- 27 A19 --- Name Object name (JHHMMSS.ss+DDMMSS.s;
<[MOK2016b] HSC JHHMMSS.ss+DDMMSS.s> in Simbad)
29 A1 --- l_imag 5σ upper limit flag on imag
31- 35 F5.2 mag imag [23.41/27.71]? Subaru/HSC i-band AB magnitude (2)
37- 40 F4.2 mag e_imag [0.02/0.9]? Uncertainty on the imag
42 A1 --- l_zmag 5σ upper limit flag on zmag
44- 48 F5.2 mag zmag [20.91/26] Subaru/HSC z-band AB magnitude (2)
50- 53 F4.2 mag e_zmag [0.01/0.7]? Uncertainty on the zmag
55- 59 F5.2 mag ymag [20.65/25.79] Subaru/HSC y band AB magnitude (2)
61- 64 F4.2 mag e_ymag [0.01/0.7] Uncertainty on the ymag
66- 70 F5.3 --- Prob [0/1] Bayesian quasar probability, PQB
72- 74 I3 min Exp [5/120] Total exposure time for the object
76- 86 A11 "Y/M/D" Date Date of observation (UT)
87- 93 A7 --- Date2 Other date(s) of observation (UT)
95 A1 --- Inst Instrument (F=Subaru/FOCAS or O=GTC/OSIRIS)
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Note (1): Object type as follows:
QSOs = quasars (69 occurrences)
Gal = Galaxies (7 occurrences)
OIII = [OIII] emitter (1 occurrence)
cDwarfs = cool dwarfs (31 occurrences)
Note (2): We took magnitudes from the Hyper Suprime-Cam Subaru Strategic
Program (HSC-SSP Public DR3; Aihara+ 2022PASJ...74..247A 2022PASJ...74..247A), corrected
for Galactic extinction.
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Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 7 A7 --- Class Object type (QSOs or cool dwarfs)
9- 27 A19 --- Name Object name (JHHMMSS.ss+DDMMSS.s)
29- 33 F5.2 mag Jmag [20.4/22.36]? J-band AB magnitude
35- 38 F4.2 mag e_Jmag [0.07/0.35]? Uncertainty on the Jmag
40- 44 F5.2 mag Hmag [19.27/21.64]? H-band AB magnitude
46- 49 F4.2 mag e_Hmag [0.04/0.28]? Uncertainty on the Hmag
51- 55 F5.2 mag Kmag [18.72/21.92]? K band AB magnitude
57- 60 F4.2 mag e_Kmag [0.03/0.43]? Uncertainty on the Kmag
62- 67 A6 --- Cam Camera (1)
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Note (1): Camera as follows:
WFCAM = UKIRT Wide-Field Camera; from the HSC-SSP Wide layer
VIRCAM = VISTA Infrared Camera; from the UKIDSS Large Area Survey
(available in the data release 11PLUS), the UKIDSS Hemisphere
Survey (DR1), the VIKING (DR5), or the VISTA Hemisphere Survey (DR6).
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Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 A4 --- Class Object type (QSOs, Gal or OIII emitter)
6- 24 A19 --- Name Object name (JHHMMSS.ss+DDMMSS.s)
26- 30 F5.3 --- z [0.95/6.94] Spectroscopic redshift (1)
32- 37 F6.2 mag 1450Mag [-25.95/-21.53] Absolute magnitude at 1450Å
39- 42 F4.2 mag e_1450Mag [0.02/0.8] 1450Mag uncertainty
44- 61 A18 --- Line Emission line
63 A1 --- l_EW 3σ upper limit flag on EW (2)
65- 67 I3 0.1nm EW [4/696]? Rest-frame equivalent width;
in Angstrom units
69- 71 I3 0.1nm e_EW [1/240]? EW uncertainty
73 A1 --- l_FWHM 3σ upper limit flag on FWHM (2)
75- 79 I5 km/s FWHM [220/16000]? Line Full Width at Half Maximum
81- 84 I4 km/s e_FWHM [20/7700]? FWHM uncertainty
86- 90 F5.2 [10-7W] logLline [40.87/45.17]? log of line luminosity in erg/s
92- 95 F4.2 [10-7W] e_logLline [0.01/0.08]? logLline uncertainty
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Note (1): The redshifts have uncertainties Δz∼0.01-0.1, depending on the
spectral features around Lyα; see text.
Note (2): 3σ upper limits are reported for objects without detectable
continuum.
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 A19 --- Name Object name (JHHMMSS.ss+DDMMSS.s)
21- 22 A2 --- SpT Approximate spectral type
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History:
From electronic version of the journal
References:
Matsuoka et al. Paper I. 2016ApJ...828...26M 2016ApJ...828...26M
Matsuoka et al. Paper II. 2018PASJ...70S..35M 2018PASJ...70S..35M
Izumi et al. Paper III. 2018PASJ...70...36I 2018PASJ...70...36I
Matsuoka et al. Paper IV. 2018ApJS..237....5M 2018ApJS..237....5M
Matsuoka et al. Paper V. 2018ApJ...869..150M 2018ApJ...869..150M
Onoue et al. Paper VI. 2019ApJ...880...77O 2019ApJ...880...77O
Izumi et al. Paper VIII. 2019PASJ...71..111I 2019PASJ...71..111I
Kato et al. Paper IX. 2020PASJ...72...84K 2020PASJ...72...84K
Matsuoka et al. Paper X. 2019ApJ...883..183M 2019ApJ...883..183M
Ishimoto et al. Paper XI. 2020ApJ...903...60I 2020ApJ...903...60I
Izumi et al. Paper XII. 2021ApJ...908..235I 2021ApJ...908..235I
Izumi et al. Paper XIII. 2021ApJ...914...36I 2021ApJ...914...36I
Onoue et al. Paper XIV. 2021ApJ...919...61O 2021ApJ...919...61O
Matsuoka et al. Paper XVI. 2022ApJS..259...18M 2022ApJS..259...18M This catalog
(End) Emmanuelle Perret [CDS] 07-Jun-2022