J/ApJ/943/67 PS1 z>5.6 QSO Survey. III. z∼6 quasar LF (Schindler+, 2023)
The Pan-STARRS1 z>5.6 Quasar Survey.
III. The z∼6 quasar luminosity function.
Schindler J.-T., Banados E., Connor T., Decarli R., Fan X., Farina E.P.,
Mazzucchelli C., Nanni R., Rix H.-W., Stern D., Venemans B.P., Walter F.
<Astrophys. J., 943, 67 (2023)>
=2023ApJ...943...67S 2023ApJ...943...67S
ADC_Keywords: QSOs; Redshifts; Magnitudes, absolute; Photometry, ugriz;
Surveys
Keywords: Quasars ; Supermassive black holes ; Reionization ; Early universe ;
Luminosity function
Abstract:
We present the z∼6 type-1 quasar luminosity function (QLF), based on
the Pan-STARRS1 (PS1) quasar survey. The PS1 sample includes
125 quasars at z∼5.7-6.2, with -28≲M1450≲-25. With the addition of
48 fainter quasars from the SHELLQs survey, we evaluate the z∼6 QLF
over -28≲M1450≲-22. Adopting a double power law with an
exponential evolution of the quasar density (Φ(z)∝10k(z-6);
k=-0.7), we use a maximum likelihood method to model our data. We find
a break magnitude of M*=-26.38-0.60+0.79mag, a faint-end slope
of α=-1.70-0.19+0.29, and a steep bright-end slope of
β=-3.84-1.21+0.63. Based on our new QLF model, we determine
the quasar comoving spatial density at z∼6 to be
n(M1450<-26)=1.16-0.12+0.13cGpc-3. In comparison with the
literature, we find the quasar density to evolve with a constant value
of k~-0.7, from z∼7 to z∼4. Additionally, we derive an ionizing
emissivity of
ε912(z=6)=7.23-1.02+1.65x1022erg/s/Hz/cMpc3, based
on the QLF measurement. Given standard assumptions, and the recent
measurement of the mean free path by Becker+ 2021MNRAS.508.1853B 2021MNRAS.508.1853B at
z∼6, we calculate an HI photoionizing rate of
ΓHI(z=6)∼6x10-16s-1, strongly disfavoring a dominant role of
quasars in hydrogen reionization.
Description:
The foundation of the quasar searches that this work builds upon is
the 3π Steradian Survey (Chambers+ 2016, II/349) that was carried
out by the Panoramic Survey Telescope and Rapid Response System
Telescope #1 (PS1). From 2009 to 2015, the PS1 3π survey imaged the
sky above a decl. of -30° in the five filter bands gP1, rP1,
iP1, zP1, and yP1.
The detailed follow-up strategy, along with descriptions of the
photometric and spectroscopic data, is presented in
Banados+ (2014AJ....148...14B 2014AJ....148...14B ; 2016, J/ApJS/227/11 and
2023, J/ApJS/265/29). The full quasar sample used in our quasar
luminosity function (QLF) analysis consists of the 125 PS1-selected
quasars that have been confirmed. Their sky distribution is shown in
Figure 1, and we provide a complete list in Appendix D (Table 7).
See Section 2.3.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table7.dat 153 125 Quasars and their properties used in the PS1
quasar luminosity function (QLF) analysis
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See also:
VII/260 : The SDSS-DR7 quasar catalog (Schneider+, 2010)
II/349 : The Pan-STARRS release 1 (PS1) Survey - DR1 (Chambers+, 2016)
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/699/782 : High-redshift SDSS-DR5 QSOs (Diamond-Stanic+, 2009)
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/MNRAS/449/4204 : WFC3/UVIS quasar-stacked spectrum at z≃2.4 (Lusso+, 2015)
J/MNRAS/448/3167 : z≳5 AGN in Chandra Deep Field-South (Weigel+, 2015)
J/ApJS/227/11 : PS1 z>5.6 quasars follow-up (Banados+, 2016)
J/ApJ/823/95 : CANDELS GOODS-S Chandra counterparts (Cappelluti+, 2016)
J/A+A/585/A87 : Quasar composite made from bright QSOs (Selsing+, 2016)
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/ApJ/841/76 : Intrinsic far-IR SED of luminous AGNs (Lyu+, 2017)
J/AJ/155/131 : z∼5 quasar LF from the CFHTLS (McGreer+, 2018)
J/ApJ/863/144 : ELQS in SDSS footprint. II. North Gal. (Schindler+, 2018)
J/ApJ/887/268 : QSOs in Southern Hemisphere (QUBRICS) (Calderone+, 2019)
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/ApJ/873/35 : Gemini GNIRS NIR sp. of QSOs at z≳5.7 (Shen+, 2019)
J/ApJS/250/26 : Spectroscopic follow-up of the QUBRICS QSOs (Boutsia+, 2020)
J/AJ/162/72 : Random forests method to discover high-z QSOs (Wenzl+, 2021)
J/A+A/668/A27 : 24 new radio-bright quasars spectra (Gloudemans+, 2022)
Byte-by-byte Description of file: table7.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 A3 --- --- [PSO]
4- 22 A19 --- PSO Quasar designation (JDDD.ddddd+DD.ddddd;
in Simbad)
24- 28 F5.2 mag ymag [19/21.5] Dereddened PS1 y-band magnitude
30- 33 F4.2 --- z [5.6/6.31] Spectroscopic redshift
35- 40 F6.2 mag M1450 [-27.5/-25.12] Calculated absolute magnitude,
M1450
42-115 A74 --- Ref Discovery reference(s)
117-153 A37 --- r_z Redshift measurement reference
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History:
From electronic version of the journal
References:
Banados et al. 2014AJ....148...14B 2014AJ....148...14B
Banados et al. Paper I. 2016ApJS..227...11B 2016ApJS..227...11B Cat. J/ApJS/227/11
Banados et al. Paper II. 2023ApJS..265...29B 2023ApJS..265...29B Cat. J/ApJS/265/29
Schindler et al. Paper III. 2023ApJ...943...67S 2023ApJ...943...67S This catalog
(End) Emmanuelle Perret [CDS] 27-Jun-2023