{
  "abstract": "We investigate the effect of $α$-core breakup on the strong conversion of \\({}^{6}_{ΛΛ}\\mathrm{He}\\) into a deeply bound \\(H\\) dibaryon. In addition to the coherent \\(H+{}^{4}\\mathrm{He}\\) channel, we evaluate the open final states \\(H+p+{}^{3}\\mathrm{H}\\), \\(H+n+{}^{3}\\mathrm{He}\\), and \\(H+d+d\\) using a translationally invariant Gaussian cluster description, including spin-isospin recoupling and full nonrelativistic three-body phase-space integrations. The breakup widths are normalized to Gal's intact-\\(α\\) result. At \\(B_{ΛΛ}^{H}=176~\\mathrm{MeV}\\), corresponding to \\(m_H\\simeq2055~\\mathrm{MeV}\\), the summed breakup width exceeds the intact-\\(α\\) width by a factor \\(R_{\\mathrm{br}}=2.49\\times10^{3}\\). The resulting inclusive width and lifetime are \\(Γ_{\\mathrm{inc}}=3.87\\times10^{-4}~\\mathrm{eV}\\) and \\(τ_{\\mathrm{inc}}=1.70\\times10^{-12}~\\mathrm{s}\\), respectively, compared with \\(τ_α=4.25\\times10^{-9}~\\mathrm{s}\\) for the intact-\\(α\\) channel alone. The mass-dependent calculation shows that the inclusive lifetime crosses the characteristic hypernuclear weak-decay timescale near \\(m_H\\simeq2020~\\mathrm{MeV}\\) and increases rapidly as the \\(H\\) mass decreases. In the representative dark-matter-motivated interval \\(1865\\leq m_H\\leq1885~\\mathrm{MeV}\\), we obtain \\(6.59\\times10^{-4}\\lesssimτ_{\\mathrm{inc}}\\lesssim 6.80\\times10^{-3}~\\mathrm{s}\\), far exceeding the weak-decay timescale. Thus, although core breakup can dominate the inclusive strong width near \\(m_H\\simeq2055~\\mathrm{MeV}\\), weakly decaying double-\\(Λ\\) hypernuclei remain compatible, within the present framework, with a deeply bound \\(uuddss\\) state in the mass range relevant to sexaquark dark matter.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.17117",
  "author_total": 2,
  "authors": [
    {
      "name": "Mahboubeh Shahrbaf"
    },
    {
      "name": "Makoto Oka"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/7nv8aqaxvtwz1.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.17117",
  "fulltext_url": null,
  "id": "7nv8aqaxvtwz1",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.17117",
  "language": null,
  "licence": "LicenseRef-arXiv-nonexclusive-1.0",
  "licence_label": "arXiv licence",
  "licence_source": "article",
  "licence_url": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "astro-ph.CO"
    ],
    [
      "arxiv",
      "hep-ph"
    ],
    [
      "arxiv",
      "nucl-th"
    ],
    [
      "openalex",
      "3106|Nuclear physics research studies"
    ]
  ],
  "openalex": "W7213424711",
  "pdf_url": "https://arxiv.org/pdf/2609.17117",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-15",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/7nv8aqaxvtwz1.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:22:01Z",
      "native_id": "2609.17117",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.17117"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.CO",
      "subfield": "cosmology"
    },
    {
      "field": "physics",
      "origin": "arxiv:hep-ph",
      "subfield": "high-energy"
    },
    {
      "field": "physics",
      "origin": "arxiv:nucl-th",
      "subfield": "nuclear"
    }
  ],
  "title": "Alpha-Core Breakup in the Strong Decay of \\({}_{ΛΛ}^{6}\\mathrm{He}\\) to a Deeply Bound \\(H\\) Dibaryon",
  "title_text": "Alpha-Core Breakup in the Strong Decay of _ΛΛ^6He to a Deeply Bound H Dibaryon",
  "type": "preprint",
  "updated_at": "2026-10-30T12:22:01Z",
  "url": "https://research.draconitic.com/paper/7nv8aqaxvtwz1",
  "venue": "arXiv",
  "versions": []
}