{
  "abstract": "We present new observations of the metal-poor ($< 0.1$ $\\rm Z_\\odot$) Type II supernova 2023ufx and its host galaxy. The deep nebular spectrum, obtained roughly a year after explosion, has a triple-peaked [O I] emission profile suggesting an asymmetric explosion. Comparison to nebular spectra models suggests a zero-age main sequence mass of $ M_{\\rm ZAMS} \\sim 25-35$ $\\rm M_\\odot$, which is supported by the low [Ca II]/[O I] emission-line ratio of $\\approx0.4$. The diminishing, broad, boxy H$α$ emission and flattening of the light curve in the late ($\\sim2$ yr) photometry suggest a complex mass-loss history in the centuries to millennia before explosion. New optical and near-infrared imaging of the host galaxy confirms that it is a dwarf, with a stellar mass of $10^{6.6\\pm0.1}$ $\\rm M_\\odot$ and a SFR of $10^{-2.5\\pm0.1}$ $\\rm M_\\odot$/yr. Results from both SED fitting and galaxy stellar mass-metallicity scaling relations all lead to an environmental metallicity estimate of $0.02-0.07$ $\\rm Z_\\odot$. Taken together, these observations confirm that SN 2023ufx is the explosion of a very metal-poor, heavily stripped red supergiant.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.04307",
  "author_total": 6,
  "authors": [
    {
      "name": "Evan Jennerjahn"
    },
    {
      "name": "Michael A. Tucker"
    },
    {
      "name": "Christopher S. Kochanek"
    },
    {
      "name": "Luc Dessart"
    },
    {
      "name": "Willem B. Hoogendam"
    },
    {
      "name": "Benjamin J. Shappee"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/bmp8mqb6tetbm.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.04307",
  "fulltext_url": null,
  "id": "bmp8mqb6tetbm",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.04307",
  "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"
    ],
    [
      "arxiv",
      "astro-ph.HE"
    ],
    [
      "arxiv",
      "astro-ph.SR"
    ],
    [
      "openalex",
      "3103|Gamma-ray bursts and supernovae"
    ]
  ],
  "openalex": "W7211909628",
  "pdf_url": "https://arxiv.org/pdf/2609.04307",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-03",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/bmp8mqb6tetbm.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:19:14Z",
      "native_id": "2609.04307",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.04307"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.GA",
      "subfield": "galaxies"
    },
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.HE",
      "subfield": "high-energy-astrophysics"
    },
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.SR",
      "subfield": "stellar"
    }
  ],
  "title": "Nebular Spectra of the Extremely Metal-Poor SN II 2023ufx Over a Year After Explosion: A Massive Progenitor and Unique Circumstellar Environment",
  "title_text": "Nebular Spectra of the Extremely Metal-Poor SN II 2023ufx Over a Year After Explosion: A Massive Progenitor and Unique Circumstellar Environment",
  "type": "preprint",
  "updated_at": "2026-10-30T12:19:14Z",
  "url": "https://research.draconitic.com/paper/bmp8mqb6tetbm",
  "venue": "arXiv",
  "versions": []
}