{ "abstract": "We present a catalogue of spectroscopically selected [O III ]+H β emitters at 6.75 < z < 9.05 and the resulting [O III ] 5008 Å luminosity function (LF) in the COSMOS field. We leveraged the 0.33 deg 2 covered by COSMOS-3D using NIRCam/WFSS F444W to perform the largest spectroscopic search for [O III ] emitters at 6.75 < z < 9.05. We present our catalogue of 249 [O III ] emitters and their associated completeness function. The inferred constraints on the [O III ] LF enabled us to characterise the knee of the [O III ] 5008 Å LF, resulting in improved [O III ] 5008 Å LF constraints at z ∼ 7, 8. Notably, we find evidence for a decline of the [O III ] luminosity density between z ∼ 6 − 8, which could be expected if the metallicity of [O III ] emitters, as well as the cosmic star-formation rate density, is declining at these redshifts. We find that theoretical models that reproduce the z ∼ 7, 8 [O III ] 5008 Å LF do not reproduce well the [O III ] equivalent width distribution, pointing to potential challenges in the modelling of [O III ] and other nebular lines in the early Universe. Finally, we provide the first constraints on the cosmic variance of [O III ] emitters, estimating at 15% the fractional uncertainty for the z ∼ 7, 8 [O III ] 5008 Å LF in the 0.33 deg 2 field. This estimate is in good agreement with that inferred from clustering, and it shows that the [O III ] 5008 Å LF derived from smaller extragalactic legacy fields is strongly affected by cosmic variance. Our results highlight the fundamental role that wide-area JWST slitless surveys play to map the galaxy large-scale structure down into the reionisation era, serving as a springboard for a variety of science cases.", "abstract_shown": true, "affiliations": [ "Department of Astronomy, University of Geneva", "Department of Astronomy, University of Michigan", "Cosmic Dawn Center (DAWN), Niels Bohr Institute, University of Copenhagen", "Steward Observatory, University of Arizona", "Hamburger Sternwarte, Universität Hamburg", "Chinese Academy of Sciences South America Center for Astronomy, National Astronomical Observatories", "Institut de Física d’Altes Energies (IFAE), The Barcelona Institute of Science and Technology, Edifici Cn, Campus UAB", "University of Geneva, 24 rue du Général-Dufour", "National Astronomical Observatory of Japan", "Departamento de Astronomía, Universidad de Chile", "European Southern Observatory", "Department of Physics, University of California, Santa Barbara", "Department of Astronomy, School of Physics, Peking University", "Kavli Institute for Astronomy and Astrophysics, Peking University", "Aix Marseille Université, CNRS, CNES, LAM (Laboratoire d’Astrophysique de Marseille), UMR 7326", "Department of Astronomy, The University of Texas at Austin", "Department of Astronomy, Tsinghua University", "Physics and Astronomy Department, Johns Hopkins University", "Space Telescope Science Institute", "Institute for Cosmic Ray Research, The University of Tokyo", "Laboratory for Multiwavelength Astrophysics, School of Physics and Astronomy, Rochester Institute of Technology", "Max-Planck-Institut für Astronomie", "Department of Astronomy and Astrophysics, The Pennsylvania State University", "Canadian Institute for Theoretical Astrophysics" ], "article_type": null, "arxiv": null, "author_total": 42, "authors": [ { "affs": [ 0 ], "name": "R. A. Meyer", "orcid": "0000-0001-5492-4522" }, { "affs": [ 1 ], "name": "Feige Wang", "orcid": "0000-0002-7633-431X" }, { "affs": [ 2 ], "name": "Koki Kakiichi", "orcid": "0000-0001-6874-1321" }, { "affs": [ 2 ], "name": "Gabe Brammer" }, { "affs": [ 3 ], "name": "Jackie Champagne", "orcid": "0000-0002-6184-9097" }, { "affs": [ 4 ], "name": "Katharina Jurk", "orcid": "0009-0007-1692-5605" }, { "affs": [ 5, 2 ], "name": "Zihao Li", "orcid": "0000-0001-5951-459X" }, { "affs": [ 5, 2 ], "name": "Z. X. Li", "orcid": "0000-0001-7634-1547" }, { "affs": [ 5 ], "name": "Marat Musin", "orcid": "0000-0002-5914-8371" }, { "affs": [ 6 ], "name": "Sindhu Satyavolu", "orcid": "0000-0001-5818-6838" }, { "affs": [ 4 ], "name": "Jan–Torge Schindler", "orcid": "0000-0002-4544-8242" }, { "affs": [ 2, 7 ], "name": "Marko Shuntov", "orcid": "0000-0002-7087-0701" }, { "affs": [ 2, 8 ], "name": "Yi Xu", "orcid": "0000-0002-5768-8235" }, { "affs": [ 5, 9 ], "name": "Siwei Zou", "orcid": "0000-0002-3983-6484" }, { "affs": [ 5, 10 ], "name": "Fuyan Bian", "orcid": "0000-0002-1620-0897" }, { "affs": [ 2, 11 ], "name": "Caitlin Casey" }, { "affs": [ 3 ], "name": "Eiichi Egami", "orcid": "0000-0003-1344-9475" }, { "affs": [ 3 ], "name": "Xiaohui Fan", "orcid": "0000-0003-3310-0131" }, { "affs": [ 12, 13 ], "name": "Danyang Jiang", "orcid": "0009-0003-6747-2221" }, { "affs": [ 14 ], "name": "Nicolas Laporte", "orcid": "0000-0001-7459-6335" }, { "affs": [ 3 ], "name": "Weizhe Liu", "orcid": "0000-0003-3762-7344" }, { "affs": [ 2, 0 ], "name": "Pascal A. Oesch", "orcid": "0000-0001-5851-6649" }, { "affs": [ 14 ], "name": "Lidia A. M. Tasca", "orcid": "0000-0001-8560-5073" }, { "affs": [ 1 ], "name": "Jinyi Yang", "orcid": "0000-0001-5287-4242" }, { "affs": [ 12, 13 ], "name": "Zijian Zhang", "orcid": "0000-0002-2420-5022" }, { "affs": [ 15 ], "name": "Hollis B. Akins", "orcid": "0000-0003-3596-8794" }, { "affs": [ 16 ], "name": "Zheng Cai", "orcid": "0000-0001-8467-6478" }, { "affs": [ 17, 18 ], "name": "Dave A. Coulter" }, { "affs": [ 11 ], "name": "Jiamu Huang", "orcid": "0000-0002-5721-0709" }, { "affs": [ 16 ], "name": "Mingyu Li", "orcid": "0000-0001-6251-649X" }, { "affs": [ 3 ], "name": "Weizhe Liu", "orcid": "0000-0003-3762-7344" }, { "affs": [ 19, 8 ], "name": "Yongming Liang", "orcid": "0000-0002-2725-302X" }, { "affs": [ 1 ], "name": "Bingcheng 秉诚 Jin 金", "orcid": "0009-0003-4862-2925" }, { "affs": [ 1 ], "name": "Xiangyu Jin", "orcid": "0000-0002-5768-738X" }, { "affs": [ 20 ], "name": "Jeyhan S. Kartaltepe", "orcid": "0000-0001-9187-3605" }, { "affs": [ 18 ], "name": "Anton M. Koekemoer", "orcid": "0000-0002-6610-2048" }, { "affs": [ 21 ], "name": "Jasleen Matharu", "orcid": "0000-0002-7547-3385" }, { "affs": [ 3 ], "name": "Maria Pudoka", "orcid": "0000-0003-4924-5941" }, { "affs": [ 22 ], "name": "Wei Leong Tee", "orcid": "0000-0003-0747-1780" }, { "affs": [ 0 ], "name": "Callum Witten", "orcid": "0000-0002-1369-6452" }, { "affs": [ 23 ], "name": "Haowen Zhang", "orcid": "0000-0002-4321-3538" }, { "affs": [ 3 ], "name": "Yongda Zhu", "orcid": "0000-0003-3307-7525" } ], "bibtex": "https://research.draconitic.com/paper/8bby7qbxezwe2.bib", "cited_by": 22, "doi": "10.1051/0004-6361/202557671", "fulltext_url": null, "id": "8bby7qbxezwe2", "issns": [ "0004-6361", "1432-0746" ], "landing_url": "https://doi.org/10.1051/0004-6361/202557671", "language": "en", "licence": "CC-BY", "licence_label": "CC BY", "licence_source": "journal", "licence_url": "https://creativecommons.org/licenses/by/4.0/", "metadata_licence": null, "native_subjects": [ [ "openalex", "3103|Galaxies: Formation, Evolution, Phenomena" ] ], "openalex": "W7165738728", "pdf_url": null, "pmcid": null, "pmid": null, "published": "2026-06-24", "publisher": "EDP Sciences", "ris": "https://research.draconitic.com/paper/8bby7qbxezwe2.ris", "sources": [ { "first_seen": "2026-11-08T13:20:39Z", "native_id": "W7165738728", "source": "openalex", "url": "https://doi.org/10.1051/0004-6361/202557671" } ], "subjects": [ { "field": "astronomy", "origin": "openalex:3103|Galaxies: Formation, Evolution, Phenomena", "subfield": "galaxies" } ], "title": "JWST COSMOS-3D: Spectroscopic census and luminosity function of [O III] emitters at 6.75 < z < 9.05 in COSMOS", "title_text": "JWST COSMOS-3D: Spectroscopic census and luminosity function of [O III] emitters at 6.75 < z < 9.05 in COSMOS", "type": "peer-reviewed", "updated_at": "2026-11-08T13:20:39Z", "url": "https://research.draconitic.com/paper/8bby7qbxezwe2", "venue": "Astronomy and Astrophysics", "versions": [] }