{
  "abstract": "{O2 stars define the hottest end of the normal O-star sequence, but their identification requires blue-optical nitrogen diagnostics absent from many surveys.} {We reassess three luminous Large Magellanic Cloud (LMC) sources with multi-epoch Sloan Digital Sky Survey V (SDSS-V) spectroscopy obtained with the Baryon Oscillation Spectroscopic Survey (BOSS) spectrographs: \\wsi, \\lh, and \\sk.} {We measure visit-resolved radial velocities and H, He, and N equivalent widths (EWs), compare robust combinations with LMC O2 templates at a common effective resolution, and use OSTAR2002 spectral energy distribution (SED) fits and a Gaia colour--magnitude diagram (CMD) as broad-band checks.} {The weighted $\\log|{\\rm EW}(\\niv~\\lambda4058)/{\\rm EW}(\\niii~\\lambda4640)|$ values are $0.64\\pm0.29$, $0.48\\pm0.23$, and $0.34\\pm0.44$ for \\wsi, \\lh, and \\sk. The detection of \\nv~$λ\\lambda4604,4620$ supports the O2~If$^\\ast$ and O2~V--III classifications adopted for \\wsi\\ and \\lh, respectively. For \\sk, the uncertain \\niv/\\niii\\ ratio and non-detection of \\nv\\ motivate O2--3~V--III. Weak \\hei~$\\lambda4471$ may indicate unresolved later-type contamination in \\wsi\\ and \\sk. The radial velocities of \\sk\\ show suggestive but non-significant variability. OSTAR2002 fits over 45--55~kK and the Gaia CMD place all three sources in the luminous very-early-O regime; \\wsi\\ shows a strong mid-infrared (MIR) excess, \\lh\\ is nearly photospheric, and \\sk\\ shows only a modest $3$--$8\\,μ$m excess.} {The BOSS spectra add \\wsi\\ and \\lh\\ to the LMC very-early-O population and identify \\sk\\ as an additional O2--3 source. These cases show how incomplete blue coverage and ambiguous catalogue associations can conceal the hottest massive stars.}",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.25464",
  "author_total": 10,
  "authors": [
    {
      "name": "A. Roman-Lopes"
    },
    {
      "name": "J. G. Fernández-Trincado"
    },
    {
      "name": "Marina Kounkel"
    },
    {
      "name": "A. A. C. Sander"
    },
    {
      "name": "Carlos G. Román-Zúñiga"
    },
    {
      "name": "A. Z. Lugo-Aranda"
    },
    {
      "name": "Sergio Sánchez-Sanjuán"
    },
    {
      "name": "Abhinna Sundar Samantaray"
    },
    {
      "name": "José Eduardo Méndez Delgado"
    },
    {
      "name": "Christian Moni Bidin"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/57g0f1bvgexe6.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.25464",
  "fulltext_url": null,
  "id": "57g0f1bvgexe6",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.25464",
  "language": null,
  "licence": "CC-BY-NC-ND-4.0",
  "licence_label": "CC BY-NC-ND 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by-nc-nd/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "astro-ph.SR"
    ],
    [
      "arxiv",
      "physics.atom-ph"
    ],
    [
      "openalex",
      "3103|Stellar, planetary, and galactic studies"
    ]
  ],
  "openalex": "W7214077084",
  "pdf_url": "https://arxiv.org/pdf/2609.25464",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-21",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/57g0f1bvgexe6.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:29:06Z",
      "native_id": "2609.25464",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.25464"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.SR",
      "subfield": "stellar"
    },
    {
      "field": "physics",
      "origin": "arxiv:physics.atom-ph",
      "subfield": "amo"
    }
  ],
  "title": "Massive stars in the SDSS-V survey: New O2 stars in the Large Magellanic Cloud",
  "title_text": "Massive stars in the SDSS-V survey: New O2 stars in the Large Magellanic Cloud",
  "type": "preprint",
  "updated_at": "2026-10-30T12:29:06Z",
  "url": "https://research.draconitic.com/paper/57g0f1bvgexe6",
  "venue": "arXiv",
  "versions": []
}