{
  "abstract": "We present the largest statistical spectroscopic sample of radio quasars at 4.7 ≤ z ≤ 6.7 to date. These have been selected from a dedicated Dark Energy Spectroscopic Instrument target program and provide a robust sample to study the influence of radio jets on early quasar evolution. Using low-frequency radio data from the LOFAR Two Metre Sky Survey Data Release 3 at 144 MHz, we identify 83 high- z radio quasars, 26 of which are classified as radio-loud (5%–15% of 646 confirmed high- z quasars, defined as R = F 5GHz / F 4400Å > 10). With radio luminosities of ∼10 ²⁵⁻²⁸ W Hz ⁻¹ , the radio emission in all 83 quasars is expected to be jet dominated rather than powered by star formation. Analysis of their rest-frame ultraviolet spectra reveals broadly similar composite spectral properties and C iv velocity shifts compared to radio-nondetected quasars. The radio-detected and radio-loud quasars exhibit slightly smaller Ly α and C iv equivalent widths on average; however, we find no significant evidence (∼1.3 σ ) for a higher fraction of weak-line quasars (∼10% ± 4% versus ∼4% ± 1% for radio-nondetected quasars). We further find that the broad absorption line (BAL) quasars are predominantly radio-quiet, and no correlation is observed between absorption index and radio-loudness, suggesting that radio emission is not produced by the BAL outflows themselves and is a physically distinct phenomenon. Our results demonstrate that powerful radio jets were already well established by z ∼ 5.",
  "abstract_shown": true,
  "affiliations": [
    "NSF NOIRLab",
    "University of Michigan",
    "Durham University",
    "University of Arizona",
    "Newcastle University",
    "University of Hertfordshire",
    "Leiden University",
    "University of Wyoming",
    "International Gemini Observatory/NSF NOIRLab",
    "ASTRON",
    "Lawrence Berkeley National Laboratory",
    "Boston University",
    "Università degli Studi di Milano",
    "INAF-Osservatorio Astronomico di Brera",
    "University College London",
    "Universidad Nacional Autónoma de México",
    "University of California, Berkeley",
    "Universidad de los Andes",
    "Institut d’Estudis Espacials de Catalunya (IEEC)",
    "Institute of Space Sciences",
    "University of Virginia",
    "Fermi National Accelerator Laboratory",
    "University of Portsmouth",
    "The University of Texas at Dallas",
    "Southern Methodist University",
    "University of California, Irvine",
    "Sorbonne Université",
    "Universitat Autònoma de Barcelona",
    "Institut de Física d’Altes Energies (IFAE)",
    "Institució Catalana de Recerca i Estudis Avançats",
    "Siena University",
    "University of Waterloo",
    "Perimeter Institute for Theoretical Physics",
    "Instituto de Astrofísica de Andalucía (CSIC)",
    "Universitat Politècnica de Catalunya",
    "Sejong University",
    "CIEMAT",
    "Space Telescope Science Institute",
    "Chinese Academy of Sciences"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 58,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Anniek J. Gloudemans",
      "orcid": "0009-0009-8274-441X"
    },
    {
      "affs": [
        1
      ],
      "name": "Jinyi Yang",
      "orcid": "0000-0001-5287-4242"
    },
    {
      "affs": [
        2
      ],
      "name": "David M. Alexander",
      "orcid": "0000-0002-5896-6313"
    },
    {
      "affs": [
        0
      ],
      "name": "Arjun Dey",
      "orcid": "0000-0002-4928-4003"
    },
    {
      "affs": [
        3
      ],
      "name": "Xiaohui Fan",
      "orcid": "0000-0003-3310-0131"
    },
    {
      "affs": [
        4
      ],
      "name": "Victoria A. Fawcett",
      "orcid": "0000-0003-1251-532X"
    },
    {
      "affs": [
        5
      ],
      "name": "Martin J. Hardcastle",
      "orcid": "0000-0003-4223-1117"
    },
    {
      "affs": [
        0
      ],
      "name": "Stephanie Juneau",
      "orcid": "0000-0002-0000-2394"
    },
    {
      "affs": [
        6
      ],
      "name": "George K. Miley",
      "orcid": "0000-0003-2884-7214"
    },
    {
      "affs": [
        2
      ],
      "name": "Leah K. Morabito",
      "orcid": "0000-0003-0487-6651"
    },
    {
      "affs": [
        7
      ],
      "name": "Adam D. Myers"
    },
    {
      "affs": [
        8
      ],
      "name": "Swayamtrupta Panda",
      "orcid": "0000-0002-5854-7426"
    },
    {
      "affs": [
        6
      ],
      "name": "Huub J. A. Röttgering",
      "orcid": "0000-0001-8887-2257"
    },
    {
      "affs": [
        6,
        9
      ],
      "name": "Timothy Shimwell",
      "orcid": "0000-0001-5648-9069"
    },
    {
      "affs": [
        5
      ],
      "name": "Daniel J. B. Smith",
      "orcid": "0000-0001-9708-253X"
    },
    {
      "affs": [
        1
      ],
      "name": "Feige Wang",
      "orcid": "0000-0002-7633-431X"
    },
    {
      "affs": [
        10
      ],
      "name": "J. Aguilar",
      "orcid": "0000-0003-0822-452X"
    },
    {
      "affs": [
        11
      ],
      "name": "S. Ahlen",
      "orcid": "0000-0001-6098-7247"
    },
    {
      "affs": [
        12,
        13
      ],
      "name": "D. Bianchi",
      "orcid": "0000-0001-9712-0006"
    },
    {
      "affs": [
        14
      ],
      "name": "D. Brooks",
      "orcid": "0000-0002-8458-5047"
    },
    {
      "affs": [
        10
      ],
      "name": "T. Claybaugh"
    },
    {
      "affs": [
        10
      ],
      "name": "A. Cuceu",
      "orcid": "0000-0002-2169-0595"
    },
    {
      "affs": [
        15
      ],
      "name": "A. de la Macorra",
      "orcid": "0000-0002-1769-1640"
    },
    {
      "affs": [
        14
      ],
      "name": "P. Doel",
      "orcid": "0000-0002-6397-4457"
    },
    {
      "affs": [
        10,
        16
      ],
      "name": "S. Ferraro",
      "orcid": "0000-0003-4992-7854"
    },
    {
      "affs": [
        17
      ],
      "name": "J. E. Forero-Romero",
      "orcid": "0000-0002-2890-3725"
    },
    {
      "affs": [
        18,
        19
      ],
      "name": "E. Gaztañaga",
      "orcid": "0000-0001-9632-0815"
    },
    {
      "affs": [
        20
      ],
      "name": "S. Gontcho A Gontcho",
      "orcid": "0000-0003-3142-233X"
    },
    {
      "affs": [
        21
      ],
      "name": "G. Gutierrez",
      "orcid": "0000-0003-0825-0517"
    },
    {
      "affs": [
        22
      ],
      "name": "C. Hahn",
      "orcid": "0000-0003-1197-0902"
    },
    {
      "affs": [
        23
      ],
      "name": "M. Ishak",
      "orcid": "0000-0002-6024-466X"
    },
    {
      "affs": [
        0
      ],
      "name": "R. Joyce",
      "orcid": "0000-0003-0201-5241"
    },
    {
      "affs": [
        24
      ],
      "name": "R. Kehoe",
      "orcid": "0000-0002-7101-697X"
    },
    {
      "affs": [
        25
      ],
      "name": "D. Kirkby",
      "orcid": "0000-0002-8828-5463"
    },
    {
      "affs": [
        10
      ],
      "name": "T. Kisner",
      "orcid": "0000-0003-3510-7134"
    },
    {
      "affs": [
        10
      ],
      "name": "A. Kremin",
      "orcid": "0000-0001-6356-7424"
    },
    {
      "affs": [
        10
      ],
      "name": "M. Landriau",
      "orcid": "0000-0003-1838-8528"
    },
    {
      "affs": [
        26
      ],
      "name": "L. Le Guillou",
      "orcid": "0000-0001-7178-8868"
    },
    {
      "affs": [
        10
      ],
      "name": "M. E. Levi",
      "orcid": "0000-0003-1887-1018"
    },
    {
      "affs": [
        27,
        28
      ],
      "name": "M. Manera",
      "orcid": "0000-0003-4962-8934"
    },
    {
      "affs": [
        0
      ],
      "name": "A. Meisner",
      "orcid": "0000-0002-1125-7384"
    },
    {
      "affs": [
        29,
        28
      ],
      "name": "R. Miquel",
      "orcid": "0000-0002-6610-4836"
    },
    {
      "affs": [
        30
      ],
      "name": "J. Moustakas",
      "orcid": "0000-0002-2733-4559"
    },
    {
      "affs": [
        22
      ],
      "name": "S. Nadathur",
      "orcid": "0000-0001-9070-3102"
    },
    {
      "affs": [
        31,
        32
      ],
      "name": "W. J. Percival",
      "orcid": "0000-0002-0644-5727"
    },
    {
      "affs": [
        33
      ],
      "name": "F. Prada",
      "orcid": "0000-0001-7145-8674"
    },
    {
      "affs": [
        34
      ],
      "name": "I. Pérez-Ràfols",
      "orcid": "0000-0001-6979-0125"
    },
    {
      "affs": [
        0
      ],
      "name": "A. Robertson"
    },
    {
      "affs": [
        35
      ],
      "name": "G. Rossi"
    },
    {
      "affs": [
        36
      ],
      "name": "E. Sanchez",
      "orcid": "0000-0002-9646-8198"
    },
    {
      "affs": [
        37
      ],
      "name": "E. F. Schlafly",
      "orcid": "0000-0002-3569-7421"
    },
    {
      "affs": [
        10
      ],
      "name": "D. Schlegel",
      "orcid": "0000-0002-5042-5088"
    },
    {
      "affs": [
        10
      ],
      "name": "J. Silber",
      "orcid": "0000-0002-3461-0320"
    },
    {
      "affs": [
        0
      ],
      "name": "D. Sprayberry",
      "orcid": "0000-0001-7583-6441"
    },
    {
      "affs": [
        1
      ],
      "name": "G. Tarlé",
      "orcid": "0000-0003-1704-0781"
    },
    {
      "affs": [
        0
      ],
      "name": "B. A. Weaver"
    },
    {
      "affs": [
        10
      ],
      "name": "R. Zhou",
      "orcid": "0000-0001-5381-4372"
    },
    {
      "affs": [
        38
      ],
      "name": "H. Zou",
      "orcid": "0000-0002-6684-3997"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/1pczrr43eg534.bib",
  "cited_by": 0,
  "doi": "10.3847/1538-4357/aeaade",
  "fulltext_url": null,
  "id": "1pczrr43eg534",
  "issns": [
    "1538-4357",
    "0004-637X"
  ],
  "landing_url": "https://iopscience.iop.org/article/10.3847/1538-4357/aeaade",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "feed-journal",
      "astronomy/general"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://iopscience.iop.org/article/10.3847/1538-4357/aeaade/pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-11-05",
  "publisher": "American Astronomical Society",
  "ris": "https://research.draconitic.com/paper/1pczrr43eg534.ris",
  "sources": [
    {
      "first_seen": "2026-11-05T12:20:12Z",
      "native_id": "10.3847/1538-4357/aeaade",
      "source": "feed-iop",
      "url": "https://iopscience.iop.org/article/10.3847/1538-4357/aeaade"
    },
    {
      "first_seen": "2026-11-05T12:20:35Z",
      "native_id": "10.3847/1538-4357/aeaade",
      "source": "crossref",
      "url": "https://iopscience.iop.org/article/10.3847/1538-4357/aeaade"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "journal-openalex:3103|Stellar, planetary, and galactic studies",
      "subfield": "stellar"
    }
  ],
  "title": "Radio Quasars in the Cosmic Dawn: A Spectroscopic Sample from the DESI Survey",
  "title_text": "Radio Quasars in the Cosmic Dawn: A Spectroscopic Sample from the DESI Survey",
  "type": "peer-reviewed",
  "updated_at": "2026-11-07T00:20:58Z",
  "url": "https://research.draconitic.com/paper/1pczrr43eg534",
  "venue": "The Astrophysical Journal",
  "versions": []
}