{
  "abstract": "We investigate freeze-in production of light dark matter through the quark flavor-changing operator $(\\bar{s}γ_μd)(\\barχγ^μχ)$ in a low-reheating cosmology. For reheating temperatures below the QCD crossover, kaon decays and scatterings generate the dark matter abundance through $K\\toπχ\\barχ$ and $Kπ\\toχ\\barχ$. The same interaction induces the rare kaon decays $K^+\\toπ^+χ\\barχ$ and $K_L\\toπ^0χ\\barχ$. This links the freeze-in relic abundance to searches at NA62, KOTO, and KOTO II. We find that lower reheating temperatures require larger couplings to compensate for the Boltzmann-suppressed kaon abundance, making kaon-driven freeze-in dark matter testable at rare kaon decay experiments.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": "Journal reference: JHEP 09 (2026) 266",
  "arxiv": "2605.05947",
  "author_total": 2,
  "authors": [
    {
      "name": "Motoi Endo"
    },
    {
      "name": "Takumu Yamanaka"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/bw2fn3dg03vhy.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2605.05947",
  "fulltext_url": null,
  "id": "bw2fn3dg03vhy",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2605.05947",
  "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.CO"
    ],
    [
      "arxiv",
      "hep-ex"
    ],
    [
      "arxiv",
      "hep-ph"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2605.05947",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-29",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/bw2fn3dg03vhy.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:25:31Z",
      "native_id": "2605.05947",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2605.05947"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.CO",
      "subfield": "cosmology"
    },
    {
      "field": "physics",
      "origin": "arxiv:hep-ex",
      "subfield": "high-energy"
    }
  ],
  "title": "Kaon Portal to Freeze-in Dark Matter",
  "title_text": "Kaon Portal to Freeze-in Dark Matter",
  "type": "preprint",
  "updated_at": "2026-10-30T12:25:31Z",
  "url": "https://research.draconitic.com/paper/bw2fn3dg03vhy",
  "venue": "arXiv",
  "versions": [
    {
      "doi": "10.1007/jhep09(2026)266",
      "pid": null,
      "relation": "published-as",
      "title": null,
      "venue": null
    }
  ]
}