{
  "abstract": "We analyze deep JWST/NIRSpec observations of 58 star-forming galaxies at $1.3< z <4.8$ in the AURORA survey to investigate the origin of the permitted OI $λ8449$ emission feature. Based on the detection of OI $λ8449$ in a stack of objects with non-detections, we infer that this feature is ubiquitous among star-forming galaxies at $\\sim$0.5% the strength of H$α$. We additionally compare our results with measurements of this line in local HII regions from the CHAOS survey and star-forming galaxies at $z<0.1619$ in the DESI survey, finding a similar strength of OI $λ8449$ relative to H$α$ in these objects. We evaluate four production mechanisms: recombination, collisional excitation, Ly$β$ fluorescence, and stellar continuum fluorescence. Of these mechanisms, stellar continuum fluorescence (rather than Ly$β$ fluorescence) provides the most compelling explanation for the OI $λ8449$ emission based on the additional detection of the near-infrared OI $λ11290$ and OI $λ13168$ emission lines. Adopting physical conditions derived from a stacked composite spectrum, we make predictions for the contribution of the other mechanisms to OI $λ8449$, determining that recombination, collisional excitation, and Ly$β$ fluorescence contribute negligibly to this feature. While a simple HII region model using Cloudy reproduces the average observed OI $λ8449$/H$α$ ratios in the AURORA sample, future works focused on refining model density profiles will be a valuable step in better explaining the near-infrared OI emission-line strengths.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.32045",
  "author_total": 14,
  "authors": [
    {
      "name": "Leonardo Clarke"
    },
    {
      "name": "Alice E. Shapley"
    },
    {
      "name": "Zhiwei Shao"
    },
    {
      "name": "Massimo Pascale"
    },
    {
      "name": "Ryan L. Sanders"
    },
    {
      "name": "Naveen A. Reddy"
    },
    {
      "name": "Tucker Jones"
    },
    {
      "name": "Harley Katz"
    },
    {
      "name": "Natalie Lam"
    },
    {
      "name": "Shreya Karthikeyan"
    },
    {
      "name": "Callum T. Donnan"
    },
    {
      "name": "Natascha M. Förster Schreiber"
    },
    {
      "name": "Anthony J. Pahl"
    },
    {
      "name": "Danielle A. Berg"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/75kzx23rxbpme.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.32045",
  "fulltext_url": null,
  "id": "75kzx23rxbpme",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.32045",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "astro-ph.GA"
    ],
    [
      "openalex",
      "3103|Galaxies: Formation, Evolution, Phenomena"
    ]
  ],
  "openalex": "W7214788722",
  "pdf_url": "https://arxiv.org/pdf/2609.32045",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-25",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/75kzx23rxbpme.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:25:12Z",
      "native_id": "2609.32045",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.32045"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.GA",
      "subfield": "galaxies"
    }
  ],
  "title": "The AURORA Survey: Determining the Production Mechanism for OI $\\mathbf{λ8449}$ Emission in Star-forming Galaxies at Cosmic Noon",
  "title_text": "The AURORA Survey: Determining the Production Mechanism for OI λ8449 Emission in Star-forming Galaxies at Cosmic Noon",
  "type": "preprint",
  "updated_at": "2026-10-30T12:25:12Z",
  "url": "https://research.draconitic.com/paper/75kzx23rxbpme",
  "venue": "arXiv",
  "versions": []
}