{
  "abstract": "We show that phase-resolved ultra-high-energy emission from LS I \\(+61^\\circ303\\) defines a critical energetic boundary linking the compact-object engine, circumstellar interaction depth, and dense-matter structure. Combining the GeV--TeV--UHE spectral transition with an orbital acceleration--transparency sieve and branch-resolved stellar sequences for 116 certified EoS, we find that the measured \\(25\\)--\\(100\\) TeV component remains energetically viable for all 116 canonical-mass EoS and therefore does not discriminate among them. EoS discrimination arises only in the deliberately more demanding pure-hadronic \\(>1\\) TeV stress-test construction: at 2.0 kpc and \\(1.4\\,M_\\odot\\), this boundary gives \\(I_{45,\\rm crit}=1.5504\\), with 82 of 116 EoS satisfying the energetic condition at\\(\\dot P_{\\rm ref}=3\\times10^{-15}\\,{\\rm s\\,s^{-1}}\\). A separately applied tidal diagnostic, \\(Λ_{1.4}\\leq580\\), is satisfied by 43 EoS, with nine satisfying both conditions. These models span several microscopic classes but occupy a narrow structural region, indicating structural overlap rather than selection of a unique EoS family. A separate GeV power-budget test requires \\(\\dot P_{\\rm rot}\\gtrsim 5.65\\times10^{-14}f_Ω\\,{\\rm s\\,s^{-1}}\\) at 2.0 kpc. For \\(f_Ω\\sim1\\), the source lies well above the UHE crossing and the EoS discrimination disappears. The UHE observation therefore identifies the engine--environment regime in which differences in neutron-star structure can become observationally discriminating, rather than defining a universal dense-matter selector.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": "Journal reference: Phys. Rev. D (2026)",
  "arxiv": "2609.08824",
  "author_total": 2,
  "authors": [
    {
      "name": "Marlon M. S. Mendes"
    },
    {
      "name": "Cesar H. Lenzi"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/fgrrvthf89r3x.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.08824",
  "fulltext_url": null,
  "id": "fgrrvthf89r3x",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.08824",
  "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.HE"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2609.08824",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-02",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/fgrrvthf89r3x.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:27:01Z",
      "native_id": "2609.08824",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.08824"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.HE",
      "subfield": "high-energy-astrophysics"
    }
  ],
  "title": "Phase-Resolved Ultra-High-Energy Emission Defines an Energetic Boundary for Compact-Object Engines and Dense-Matter Structure",
  "title_text": "Phase-Resolved Ultra-High-Energy Emission Defines an Energetic Boundary for Compact-Object Engines and Dense-Matter Structure",
  "type": "preprint",
  "updated_at": "2026-10-30T12:27:01Z",
  "url": "https://research.draconitic.com/paper/fgrrvthf89r3x",
  "venue": "arXiv",
  "versions": [
    {
      "doi": "10.1103/rlqk-r5xq",
      "pid": null,
      "relation": "published-as",
      "title": null,
      "venue": null
    }
  ]
}