{
  "abstract": "High-redshift active galactic nuclei (AGN) are powerful probes of early black-hole growth, galaxy formation, and the evolving intergalactic medium (IGM). We use Lumina, a cosmological radiation-hydrodynamic simulation spanning the epochs of hydrogen and helium reionization, which combines a large (500 cMpc)3 volume with 2 × 60003 resolution elements, to explore high-redshift AGN. The simulation self-consistently follows hundreds of millions of galaxies and supermassive black holes (SMBHs), together with their impact on the IGM. We exploit this uniquely large dynamic range to predict multi-band AGN luminosity functions (LFs) at z ≥ 3, from hard X-rays to the mid-infrared. These predictions encompass both moderately luminous quasars and the faint “Little Red Dots” (LRDs) uncovered by JWST. We develop an empirical model that maps simulated SMBHs onto observed AGN using bolometric and extinction/absorption corrections for canonical AGN and LRDs, and in which SMBHs with $M_{\\rm BH}\\le 10\\, M_{\\rm seed} \\sim 10^{7}{\\, \\rm M_\\odot }$ stay in the LRD phase with a duty cycle of 30%. This simple framework reproduces the observed LFs and clustering of LRDs. Meanwhile, the pre-JWST quasar LF constraints are recovered, although we find that a ∼0.3 dex log-normal scatter in bolometric luminosity is required to reproduce the bright end. We quantify the redshift evolution of AGN and LRD number densities, and their contributions to the integrated BH mass densities. The same AGN population is the dominant driver for the He ii reionization modelled self-consistently in Lumina. This paves the way for general population-synthesis models of high-redshift AGN, including LRDs, in a unified cosmological framework.",
  "abstract_shown": true,
  "affiliations": [
    "Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology Department of Physics, , Cambridge, MA 02139 ,",
    "Center for Astrophysics | Harvard & Smithsonian , 60 Garden Street, Cambridge, MA 02138 ,",
    "The University of Texas at Dallas Department of Physics, , Richardson, TX 75080 ,",
    "York University Department of Physics and Astronomy, , 4700 Keele Street, Toronto, ON M3J 1P3 ,",
    "Fachbereich Physik, Philipps Universität Marburg , D-35032 Marburg ,",
    "Max Planck Institute for Astronomy , Königstuhl 17, D-69117 Heidelberg ,",
    "Durham University Centre for Extragalactic Astronomy, Department of Physics, , Durham DH1 3LE ,",
    "Kavli Institute for Astronomy and Astrophysics, Peking University , Beijing 100871 ,",
    "School of Physics, Peking University Department of Astronomy, , Beijing 100871 ,",
    "The University of Texas at Austin Department of Astronomy, , Austin, TX 78712 ,",
    "Cosmic Frontier Center, The University of Texas at Austin , Austin, TX 78712 ,",
    "Dartmouth College Department of Physics and Astronomy, , 6127 Wilder Laboratory, Hanover, NH 03755 ,",
    "Max Planck Institute for Astrophysics , Karl-Schwarzschild-Str. 1, D-85741 Garching ,"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 18,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Xuejian Shen"
    },
    {
      "affs": [
        1
      ],
      "name": "Oliver Zier",
      "orcid": "0000-0003-1811-8915"
    },
    {
      "affs": [
        2
      ],
      "name": "Aaron Smith",
      "orcid": "0000-0002-2838-9033"
    },
    {
      "affs": [
        1
      ],
      "name": "Rongrong Liu"
    },
    {
      "affs": [
        3
      ],
      "name": "Rahul Kannan",
      "orcid": "0000-0001-6092-2187"
    },
    {
      "affs": [
        0
      ],
      "name": "Teodora-Elena Bulichi",
      "orcid": "0000-0001-8174-6389"
    },
    {
      "affs": [
        1
      ],
      "name": "Sonja M Koehler"
    },
    {
      "affs": [
        0,
        4
      ],
      "name": "Volker Springel Mark Vogelsberger",
      "orcid": "0000-0001-8593-7692"
    },
    {
      "affs": [
        1
      ],
      "name": "Lars Hernquist"
    },
    {
      "affs": [
        0
      ],
      "name": "Rohan P Naidu"
    },
    {
      "affs": [
        1,
        5
      ],
      "name": "Anna de Graaff",
      "orcid": "0000-0002-2380-9801"
    },
    {
      "affs": [
        1
      ],
      "name": "Elia Pizzati",
      "orcid": "0000-0002-9712-0038"
    },
    {
      "affs": [
        6
      ],
      "name": "David M Alexander"
    },
    {
      "affs": [
        7,
        8
      ],
      "name": "Luis C Ho"
    },
    {
      "affs": [
        9,
        10
      ],
      "name": "Vasily Kokorev"
    },
    {
      "affs": [
        0
      ],
      "name": "Gene Leung"
    },
    {
      "affs": [
        0
      ],
      "name": "Anna-Christina Eilers",
      "orcid": "0000-0003-2895-6218"
    },
    {
      "affs": [
        11,
        12
      ],
      "name": "Ryan C Hickox"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/0rqg1wab1bthb.bib",
  "cited_by": 0,
  "doi": "10.1093/mnras/stag2082",
  "fulltext_url": null,
  "id": "0rqg1wab1bthb",
  "issns": [
    "0035-8711",
    "1365-2966"
  ],
  "landing_url": "https://academic.oup.com/mnras/advance-article/doi/10.1093/mnras/stag2082/9005965",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "journal",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [],
  "openalex": null,
  "pdf_url": "https://academic.oup.com/mnras/advance-article-pdf/doi/10.1093/mnras/stag2082/72655270/stag2082.pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-31",
  "publisher": "Oxford University Press (OUP)",
  "ris": "https://research.draconitic.com/paper/0rqg1wab1bthb.ris",
  "sources": [
    {
      "first_seen": "2026-11-01T00:20:40Z",
      "native_id": "10.1093/mnras/stag2082",
      "source": "crossref",
      "url": "https://academic.oup.com/mnras/advance-article/doi/10.1093/mnras/stag2082/9005965"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "journal-openalex:3103|Stellar, planetary, and galactic studies",
      "subfield": "stellar"
    }
  ],
  "title": "The Lumina Project: The Demographics of Active Galactic Nuclei from Quasars to Little Red Dots at z ≥ 3",
  "title_text": "The Lumina Project: The Demographics of Active Galactic Nuclei from Quasars to Little Red Dots at z ≥ 3",
  "type": "peer-reviewed",
  "updated_at": "2026-11-02T00:20:49Z",
  "url": "https://research.draconitic.com/paper/0rqg1wab1bthb",
  "venue": "Monthly Notices of the Royal Astronomical Society",
  "versions": []
}