{
  "abstract": "$K_L \\rightarrow π^0ν\\barν$ is a golden mode for flavour physics: it is highly suppressed in the Standard Model, with a predicted branching ratio of $3 \\times 10^{-11}$ and a theoretical uncertainty of just 2\\%, and is therefore extremely sensitive to new physics. The KOTO experiment at J-PARC is searching for this decay. Using the data taken in 2021, it has set the most stringent upper limit to date of $2.2 \\times 10^{-9}$ on the branching ratio at 90\\% C.L. We present KOTO II, a next-generation experiment at J-PARC proposed in 2024, which aims to measure the $K_L \\rightarrow π^0ν\\barν$ branching ratio with a sensitivity below $10^{-12}$ in the 2030s.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2611.08514",
  "author_total": 1,
  "authors": [
    {
      "name": "Silvia Martellotti"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/c7ta8f7c3c961.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2611.08514",
  "fulltext_url": null,
  "id": "c7ta8f7c3c961",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2611.08514",
  "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",
      "hep-ex"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2611.08514",
  "pmcid": null,
  "pmid": null,
  "published": "2026-11-01",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/c7ta8f7c3c961.ris",
  "sources": [
    {
      "first_seen": "2026-11-10T06:21:04Z",
      "native_id": "2611.08514",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2611.08514"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:hep-ex",
      "subfield": "high-energy"
    }
  ],
  "title": "The Koto II experiment",
  "title_text": "The Koto II experiment",
  "type": "preprint",
  "updated_at": "2026-11-10T06:21:04Z",
  "url": "https://research.draconitic.com/paper/c7ta8f7c3c961",
  "venue": "arXiv",
  "versions": []
}