A Caltech Library Service

The Bolometric Quasar Luminosity Function at z = 0-7

Shen, Xuejian and Hopkins, Philip F. and Faucher-Giguère, Claude-André and Alexander, D. M. and Richards, Gordon T. and Ross, Nicholas P. and Hickox, R. C. (2020) The Bolometric Quasar Luminosity Function at z = 0-7. Monthly Notices of the Royal Astronomical Society, 495 (3). pp. 3252-3275. ISSN 0035-8711. doi:10.1093/mnras/staa1381.

[img] PDF - Published Version
See Usage Policy.

[img] PDF - Submitted Version
See Usage Policy.


Use this Persistent URL to link to this item:


In this paper, we provide updated constraints on the bolometric quasar luminosity function (QLF) from z = 0 to z = 7. The constraints are based on an observational compilation that includes observations in the rest-frame IR, B band, UV, soft, and hard X-ray in past decades. Our method follows Hopkins et al. with an updated quasar SED model and bolometric and extinction corrections. The new best-fitting bolometric quasar luminosity function behaves qualitatively different from the old Hopkins model at high redshift. Compared with the old model, the number density normalization decreases towards higher redshift and the bright-end slope is steeper at z ≳ 2. Due to the paucity of measurements at the faint end, the faint end slope at z ≳ 5 is quite uncertain. We present two models, one featuring a progressively steeper faint-end slope at higher redshift and the other featuring a shallow faint-end slope at z ≳ 5. Further multiband observations of the faint-end QLF are needed to distinguish between these models. The evolutionary pattern of the bolometric QLF can be interpreted as an early phase likely dominated by the hierarchical assembly of structures and a late phase likely dominated by the quenching of galaxies. We explore the implications of this model on the ionizing photon production by quasars, the CXB spectrum, the SMBH mass density, and mass functions. The predicted hydrogen photoionization rate contributed by quasars is subdominant during the epoch of reionization and only becomes important at z ≲ 3. The predicted CXB spectrum, cosmic SMBH mass density, and SMBH mass function are generally consistent with existing observations.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Shen, Xuejian0000-0002-6196-823X
Hopkins, Philip F.0000-0003-3729-1684
Faucher-Giguère, Claude-André0000-0002-4900-6628
Alexander, D. M.0000-0002-5896-6313
Ross, Nicholas P.0000-0003-1830-6473
Hickox, R. C.0000-0003-1468-9526
Additional Information:© 2020 The Author(s). Published by Oxford University Press on behalf of the Royal Astronomical Society This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model ( Accepted 2020 May 8. Received 2020 April 23; in original form 2019 December 22. Published: 20 May 2020. Support for PFH was provided by an Alfred P. Sloan Research Fellowship, National Science Foundation (NSF) Collaborative Research grant #1715847 and CAREER grant #1455342. CAFG was supported by NSF through grants AST-1517491, AST-1715216, and CAREER award AST-1652522; by National Aeronautics and Space Administration (NASA) through grant 17-ATP17-0067; and by a Cottrell Scholar Award and Scialog Award #26968 from the Research Corporation for Science Advancement. NPR acknowledges support from the Science and Technology Facilities Council (STFC) and the Ernest Rutherford Fellowship scheme. GTR was supported in part by NASA Astrophysics Data Analysis Program (ADAP) grant NNX17AF04G. DMA thanks the STFC for support through grant code ST/P000541/1. Numerical calculations were run on the Caltech computer cluster ‘Wheeler’.
Group:Astronomy Department, TAPIR
Funding AgencyGrant Number
Alfred P. Sloan FoundationUNSPECIFIED
Cottrell Scholar of Research Corporation26968
Science and Technology Facilities Council (STFC)ST/P000541/1
Subject Keywords:galaxies: active – galaxies: nuclei – quasars: general – cosmology: observations – infrared: galaxies – ultraviolet: galaxies
Issue or Number:3
Record Number:CaltechAUTHORS:20200310-093310026
Persistent URL:
Official Citation:Xuejian Shen, Philip F Hopkins, Claude-André Faucher-Giguère, D M Alexander, Gordon T Richards, Nicholas P Ross, R C Hickox, The bolometric quasar luminosity function at z = 0–7, Monthly Notices of the Royal Astronomical Society, Volume 495, Issue 3, July 2020, Pages 3252–3275,
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:101816
Deposited By: Tony Diaz
Deposited On:10 Mar 2020 17:54
Last Modified:16 Nov 2021 18:06

Repository Staff Only: item control page