{
  "abstract": "The LUX-ZEPLIN experiment has reported a nuclear-recoil candidate near 248 keV. We investigate a decay source for an endothermic interpretation: a long-lived dark parent produces energetic ground-state particles that upscatter on xenon. The parent mass fixes the injection energy, while its lifetime determines the absolute flux through the Galactic dark-matter column density. We include the Doppler broadening from parent and observer motion and use exact scattering kinematics with natural xenon isotopes. For a scalar contact interaction, a benchmark with a 10 MeV incident state and a 506 MeV parent gives an efficiency-weighted recoil spectrum peaked at 248.5 keV. One event in a specified high-energy window requires $τ_X \\simeq 4.4 \\times 10^{20}$ s $f_X [σ_{\\text{ref}}/(10^{-36} \\text{cm}^2)]$, with a normalization sensitive to the nuclear response. We quantify the accompanying elastic-scattering requirement and the target-dependent thresholds. The calculation identifies a decay realization of the boosted flux and the portal conditions needed to preserve the recoil signal; a detector-level fit and ultraviolet-specific constraints remain necessary for a complete experimental assessment.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.37545",
  "author_total": 3,
  "authors": [
    {
      "name": "Yongsoo Jho"
    },
    {
      "name": "Sanghwan Kim"
    },
    {
      "name": "Seong Chan Park"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/2g47hbfhfcqsz.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.37545",
  "fulltext_url": null,
  "id": "2g47hbfhfcqsz",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.37545",
  "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",
      "hep-ph"
    ],
    [
      "arxiv",
      "physics.ins-det"
    ],
    [
      "openalex",
      "3106|Dark Matter and Cosmic Phenomena"
    ]
  ],
  "openalex": "W7214952024",
  "pdf_url": "https://arxiv.org/pdf/2609.37545",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-29",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/2g47hbfhfcqsz.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:25:31Z",
      "native_id": "2609.37545",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.37545"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:physics.ins-det",
      "subfield": "applied-instrumentation"
    },
    {
      "field": "physics",
      "origin": "arxiv:hep-ph",
      "subfield": "high-energy"
    }
  ],
  "title": "Endothermic Dark Matter at LZ from a Decaying Parent",
  "title_text": "Endothermic Dark Matter at LZ from a Decaying Parent",
  "type": "preprint",
  "updated_at": "2026-10-30T12:25:31Z",
  "url": "https://research.draconitic.com/paper/2g47hbfhfcqsz",
  "venue": "arXiv",
  "versions": []
}