We present the $z\!\approx\!6$ type-1 quasar luminosity function (QLF) based
on the Pan-STARRS1 (PS1) quasar survey. The PS1 sample includes 125 quasars at
$z\approx5.7-6.2$ with $-28M_1450łesssim-25$. Complemented by 48
fainter quasars from the SHELLQs survey, we evaluate the $z\approx6$ QLF over
$-28M_1450łesssim-22$. Adopting a double power law with an
exponential evolution of the quasar density ($\Phi(z)\propto10^k(z-6)$;
$k=-0.7$), we use a maximum likelihood method to model our data. We find a
break magnitude of $M^*=-26.38_-0.60^+0.79\,mag$, a faint end slope
of $\alpha=-1.70_-0.19^+0.29$, and a steep bright end slope with
$\beta=-3.84_-1.21^+0.63$. % Based on our new QLF model we determine the
quasar comoving spatial density at $z\!\approx\!6$ to be $n(
M_1450<-26)=1.16_-0.12^+0.13\,cGpc^-3$. In comparison with the
literature, we find the quasar density to evolve with a constant value of
$k\approx-0.7$ from $z\approx7$ to $z\approx4$. % Additionally, we derive an
ionizing emissivity of $\epsilon_912(z=6) =7.23_-1.02^+1.65\times
10^22\,erg\,s^-1Hz^-1cMpc^-3$ based on the
QLF measurement. Given standard assumptions and the recent measurement of the
mean free path of Becker et al. (2021) at $z\approx6$ we calculate an HI
photoionizing rate of $\Gamma_HI(z=6) 6
\times10^-16\,s^-1$, strongly disfavoring a dominant role of quasars
in hydrogen reionization.
Описание
The Pan-STARRS1 $\mathbf{z>5.6}$ Quasar Survey: III. The $\mathbf{z\approx6}$ Quasar Luminosity Function
%0 Generic
%1 schindler2022panstarrs1
%A Schindler, Jan-Torge
%A Bañados, Eduardo
%A Connor, Thomas
%A Decarli, Roberto
%A Fan, Xiaohui
%A Farina, Emanuele Paolo
%A Mazzucchelli, Chiara
%A Nanni, Riccardo
%A Rix, Hans-Walter
%A Stern, Daniel
%A Venemans, Bram P.
%A Walter, Fabian
%D 2022
%K library
%T The Pan-STARRS1 $z>5.6$ Quasar Survey: III. The
$z\approx6$ Quasar Luminosity Function
%U http://arxiv.org/abs/2212.04179
%X We present the $z\!\approx\!6$ type-1 quasar luminosity function (QLF) based
on the Pan-STARRS1 (PS1) quasar survey. The PS1 sample includes 125 quasars at
$z\approx5.7-6.2$ with $-28M_1450łesssim-25$. Complemented by 48
fainter quasars from the SHELLQs survey, we evaluate the $z\approx6$ QLF over
$-28M_1450łesssim-22$. Adopting a double power law with an
exponential evolution of the quasar density ($\Phi(z)\propto10^k(z-6)$;
$k=-0.7$), we use a maximum likelihood method to model our data. We find a
break magnitude of $M^*=-26.38_-0.60^+0.79\,mag$, a faint end slope
of $\alpha=-1.70_-0.19^+0.29$, and a steep bright end slope with
$\beta=-3.84_-1.21^+0.63$. % Based on our new QLF model we determine the
quasar comoving spatial density at $z\!\approx\!6$ to be $n(
M_1450<-26)=1.16_-0.12^+0.13\,cGpc^-3$. In comparison with the
literature, we find the quasar density to evolve with a constant value of
$k\approx-0.7$ from $z\approx7$ to $z\approx4$. % Additionally, we derive an
ionizing emissivity of $\epsilon_912(z=6) =7.23_-1.02^+1.65\times
10^22\,erg\,s^-1Hz^-1cMpc^-3$ based on the
QLF measurement. Given standard assumptions and the recent measurement of the
mean free path of Becker et al. (2021) at $z\approx6$ we calculate an HI
photoionizing rate of $\Gamma_HI(z=6) 6
\times10^-16\,s^-1$, strongly disfavoring a dominant role of quasars
in hydrogen reionization.
@misc{schindler2022panstarrs1,
abstract = {We present the $z\!\approx\!6$ type-1 quasar luminosity function (QLF) based
on the Pan-STARRS1 (PS1) quasar survey. The PS1 sample includes 125 quasars at
$z\approx5.7-6.2$ with $-28\lesssim M_{1450}\lesssim-25$. Complemented by 48
fainter quasars from the SHELLQs survey, we evaluate the $z\approx6$ QLF over
$-28\lesssim M_{1450}\lesssim-22$. Adopting a double power law with an
exponential evolution of the quasar density ($\Phi(z)\propto10^{k(z-6)}$;
$k=-0.7$), we use a maximum likelihood method to model our data. We find a
break magnitude of $M^*=-26.38_{-0.60}^{+0.79}\,\text{mag}$, a faint end slope
of $\alpha=-1.70_{-0.19}^{+0.29}$, and a steep bright end slope with
$\beta=-3.84_{-1.21}^{+0.63}$. % Based on our new QLF model we determine the
quasar comoving spatial density at $z\!\approx\!6$ to be $n(
M_{1450}<-26)=1.16_{-0.12}^{+0.13}\,\text{cGpc}^{-3}$. In comparison with the
literature, we find the quasar density to evolve with a constant value of
$k\approx-0.7$ from $z\approx7$ to $z\approx4$. % Additionally, we derive an
ionizing emissivity of $\epsilon_{912}(z=6) =7.23_{-1.02}^{+1.65}\times
10^{22}\,\text{erg}\,\text{s}^{-1}\text{Hz}^{-1}\text{cMpc}^{-3}$ based on the
QLF measurement. Given standard assumptions and the recent measurement of the
mean free path of Becker et al. (2021) at $z\approx6$ we calculate an HI
photoionizing rate of $\Gamma_{\text{HI}}(z{=}6) \approx 6
\times10^{-16}\,\text{s}^{-1}$, strongly disfavoring a dominant role of quasars
in hydrogen reionization.},
added-at = {2022-12-09T08:49:11.000+0100},
author = {Schindler, Jan-Torge and Bañados, Eduardo and Connor, Thomas and Decarli, Roberto and Fan, Xiaohui and Farina, Emanuele Paolo and Mazzucchelli, Chiara and Nanni, Riccardo and Rix, Hans-Walter and Stern, Daniel and Venemans, Bram P. and Walter, Fabian},
biburl = {https://www.bibsonomy.org/bibtex/29cd0f3cb72c9054833a31e29ce0cd9f0/gpkulkarni},
description = {The Pan-STARRS1 $\mathbf{z>5.6}$ Quasar Survey: III. The $\mathbf{z\approx6}$ Quasar Luminosity Function},
interhash = {c8c4c26ccb9a673d977e91a86ac6748b},
intrahash = {9cd0f3cb72c9054833a31e29ce0cd9f0},
keywords = {library},
note = {cite arxiv:2212.04179Comment: ApJ accepted, 40 pages, 19 Figures},
timestamp = {2022-12-09T08:49:11.000+0100},
title = {The Pan-STARRS1 $\mathbf{z>5.6}$ Quasar Survey: III. The
$\mathbf{z\approx6}$ Quasar Luminosity Function},
url = {http://arxiv.org/abs/2212.04179},
year = 2022
}