{
  "abstract": "We investigate cold homogeneous matter composed of neutrons, protons, and $Λ$ hyperons within our hyperonic extension of the lowest-order constrained variational (LOCV) method, hereafter denoted LOCVY. Our earlier LOCVY calculation, based on two-baryon interactions, is extended by supplementing the Argonne $v_{18}$ nucleonic interaction with the Urbana IX three-nucleon force, reduced within the variational framework to a correlation-weighted density-dependent effective two-nucleon interaction. The $NΛ$ and $ΛΛ$ interactions are kept unchanged, allowing the present calculation to isolate the competition between hyperon-induced softening and nucleonic three-body repulsion. The energy per baryon is calculated for fixed $Λ$ fractions $Y_Λ=0$, $0.1$, and $0.2$ in matter with a symmetric nucleonic component and in the proton-free neutron--$Λ$ limit. Direct differences between calculations with and without the three-body force quantify its density-dependent contribution, while a complementary decomposition into $NN$, $NΛ$, and $ΛΛ$ terms identifies the microscopic origin of the stiffening. The Urbana contribution becomes increasingly repulsive with density and opposes, but does not generically remove, the softening associated with a finite $Λ$ content. We further investigate the saturation properties for several prescribed $Λ$ fractions, with and without the nucleonic three-body force, to clarify how strangeness and many-body interactions modify the saturation point and the agreement with empirical nuclear-matter properties.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.00851",
  "author_total": 1,
  "authors": [
    {
      "name": "Mahboubeh Shahrbaf"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/ajjc14j7sc9s1.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.00851",
  "fulltext_url": null,
  "id": "ajjc14j7sc9s1",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.00851",
  "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",
      "nucl-th"
    ],
    [
      "openalex",
      "3106|Nuclear physics research studies"
    ]
  ],
  "openalex": "W7206153021",
  "pdf_url": "https://arxiv.org/pdf/2609.00851",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-01",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/ajjc14j7sc9s1.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:18:00Z",
      "native_id": "2609.00851",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.00851"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:nucl-th",
      "subfield": "nuclear"
    }
  ],
  "title": "Hyperonic Softening versus Nucleonic Three-Body Repulsion in Hypernuclear Matter within a microscopic approach",
  "title_text": "Hyperonic Softening versus Nucleonic Three-Body Repulsion in Hypernuclear Matter within a microscopic approach",
  "type": "preprint",
  "updated_at": "2026-10-30T12:18:00Z",
  "url": "https://research.draconitic.com/paper/ajjc14j7sc9s1",
  "venue": "arXiv",
  "versions": []
}