J/ApJ/928/172 3.5<z<5.0 SDSS quasars UV luminosity function (Pan+, 2022)
Quasar UV luminosity function at 3.5<z<5.0 from SDSS deep imaging data.
Pan Z., Jiang L., Fan X., Wu J., Yang J.
<Astrophys. J., 928, 172 (2022)>
=2022ApJ...928..172P 2022ApJ...928..172P
ADC_Keywords: QSOs; Spectra, optical; Redshifts; Surveys; Photometry, SDSS;
Magnitudes, absolute; Ultraviolet
Keywords: Quasars ; Redshift surveys ; Luminosity function
Abstract:
We present a well-designed sample of more than 1000 type 1 quasars at
3.5<z<5 and derive UV quasar luminosity functions (QLFs) in this
redshift range. These quasars were selected using the Sloan Digital
Sky Survey (SDSS) imaging data in the Stripe 82 and overlap regions
with repeat imaging observations that are about 1mag fainter than the
SDSS single-epoch data. The follow-up spectroscopic observations were
conducted by the SDSS-III Baryon Oscillation Spectroscopic Survey
(BOSS) as one of the BOSS ancillary programs. Reaching i∼21.5mag, our
sample bridges previous samples from brighter and deeper surveys. We
use a 1/Va method to derive binned QLFs at 3.6<z<4.0, 4.0<z<4.5, and
4.5<z<4.9 and then use a double power-law model to parameterize the
QLFs. We also combine our data with literature QLFs to better
constrain the QLFs across a much wider luminosity baseline. The faint-
and bright-end slopes of the QLFs in this redshift range are around
-1.7 and -3.7, respectively, with uncertainties from 0.2 to 0.3 to
>0.5. The evolution of the QLFs from z∼5 to 3.5 can be described by a
pure density evolution model (∝10kz) with a parameter k
similar to that at 5<z<7, suggesting a nearly uniform evolution of the
quasar density at z=3.5-7.
Description:
Our targets were selected from the SDSS Data Release 7 (DR7) imaging
data and were observed by the BOSS spectrograph in SDSS-III.
The BOSS main survey covered ∼10000deg2 in the north and south
galactic caps and was completed in 2014. From the spectroscopic
observations, we obtained 887 quasars. They have been included in the
SDSS DR16 quasar catalog (Lyke+ 2020, VII/289).
Our final high-redshift sample, including 974 quasars in 1292deg2 of
the SDSS overlap regions and 224 quasars in 225deg2 of Stripe 82, is
the combination of the archival and new samples and consists of
1198 quasars at z>3.
See Sections 2 and 3.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 156 1198 High-redshift quasar catalog
fig6.dat 48 35 Binned quasar luminosity functions (QLFs) at
3.6<z<4.9 derived from our sample
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See also:
VII/241 : The 2dF QSO Redshift Survey (Croom+ 2004)
II/294 : The SDSS Photometric Catalog, Release 7 (Adelman-McCarthy+, 2009)
V/154 : Sloan Digital Sky Surveys (SDSS), Release 16 (DR16) (Ahumada+, 2020)
VII/289 : SDSS quasar catalog, sixteenth data release (DR16Q) (Lyke+, 2020)
J/AJ/131/2766 : Quasar luminosity function from SDSS-DR3 (Richards+, 2006)
J/ApJ/710/1498 : QSO luminosity function at z∼4 (Glikman+, 2010)
J/ApJ/743/125 : Likelihood method for QSOs selection (Kirkpatrick+, 2011)
J/ApJ/755/169 : 3<z<5 QSO luminosity function in the COSMOS (Masters+, 2012)
J/ApJS/199/3 : The quasars MMT-BOSS pilot survey (Ross+, 2012)
J/ApJ/746/169 : Luminosity function of broad-line quasars (Shen+, 2012)
J/ApJ/768/105 : z∼5 QSO LF from SDSS Stripe 82 (McGreer+, 2013)
J/ApJ/773/14 : BOSS: quasar luminosity function (Ross+, 2013)
J/ApJ/794/120 : Sloan Digital Sky Survey coadd. Stripe 82 (Annis+, 2014)
J/ApJ/819/24 : z>4.5 QSOs with SDSS and WISE. I. Opt. spectra (Wang+, 2016)
J/ApJ/829/33 : Luminous of high-z QSOs with SDSS and WISE. II (Yang+, 2016)
J/AJ/155/131 : z∼5 QSO luminosity function from the CFHTLS (McGreer+, 2018)
J/MNRAS/488/1035 : AGN UV luminosity function (Kulkarni+, 2019)
J/ApJ/871/258 : ELQS in SDSS. III. Full ELQS quasar cat. (Schindler+, 2019)
J/ApJS/254/6 : Finding QSOs behind the Galactic Plane. I. (Fu+, 2021)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 18 A18 --- SDSS SDSS identifier (HHMMSS.ss+DDMMSS.s; J2000)
20- 31 F12.8 deg RAdeg Right Ascension in decimal degrees (J2000)
33- 42 F10.7 deg DEdeg [-3/68] Declination in decimal degrees (J2000)
44- 50 F7.5 --- z [3.16/5.4] Redshift
52 I1 --- f_z [0/1]? Flag on z (1)
54- 61 A8 --- Region Region identifier (2)
63- 70 F8.5 --- Index [-2.94/0.9] Continuum power-law index
72- 78 F7.5 --- e_Index [0.044/0.7]? Uncertainty in Index
80- 88 F9.5 mag M1450 [-28/-23.59] Absolute magnitude at 1450Å
90- 95 F6.3 mag umag [21.6/30] SDSS coadded u band AB magnitude;
corrected for the extinction
97-101 F5.3 mag e_umag [0.1/4.8] Uncertainty in umag
103-108 F6.3 mag gmag [19/30] SDSS coadded g band AB magnitude
corrected for the extinction
110-114 F5.3 mag e_gmag [0.004/4.4] Uncertainty in gmag
116-121 F6.3 mag rmag [17.7/23.7] SDSS coadded r band AB magnitude
corrected for the extinction
123-127 F5.3 mag e_rmag [0.002/0.3] Uncertainty in rmag
129-137 F9.6 mag imag [17.8/21.5] SDSS coadded i band AB magnitude
corrected for the extinction
139-143 F5.3 mag e_imag [0.003/0.2] Uncertainty in imag
145-150 F6.3 mag zmag [17.79/22] SDSS coadded z band AB magnitude
corrected for the extinction
152-156 F5.3 mag e_zmag [0.009/0.4] Uncertainty in zmag
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Note (1): Flag on redshift as follows:
0 = spectroscopic redshift from this study (852 occurrences)
1 = spectroscopic redshift from SDSS DR7 (346 occurrences)
Note (2): Region as follows:
overlap = the overlap regions. The magnitudes for the overlap regions
are combined magnitudes. 974 occurrences
Stripe82 = SDSS Stripe 82. The magnitudes for the Stripe 82 are from the
SDSS Query CasJobs online server or DR7Q depending on whether
they have previous spectroscopic observations. 224 occurrences.
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Byte-by-byte Description of file: fig6.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- Region Region identifier (1)
6 I1 --- z [1/3] Redshift range (2)
8- 13 F6.2 mag Medmag [-26.9/-24.2] Median absolute
magnitude at 1450Å (M1450)
magnitude
15- 20 F6.2 mag Meanmag [-27.2/-24.2] Mean M1450 magnitude
22- 25 F4.2 mag magerr [0.15/0.5] Uncertainty in the
median/mean magnitudes
27- 32 F6.2 10-9.Mpc-3.mag-1 Den [5/278] Density
34- 38 F5.2 10-9.Mpc-3.mag-1 e_Den [2.7/74] Uncertainty in Den
40- 42 I3 --- N [4/108] Number of sources in the
magnitude bin
44- 48 F5.1 --- Ncor [4.6/717] Number of source after
incompleteness correction
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Note (1): Region identifier as follows:
Over = overlap regions;
S82 = SDSS Stripe 82.
Note (2): Redshift range as follows:
1 = 3.6<z<4.0
2 = 4.0<z<4.5
3 = 4.5<z<4.9
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 04-Mar-2024