{
  "abstract": "We report a new partial lifetime limit of $4.2 \\times 10^{32}$ years for the trinucleon decay mode $^{16}\\text{O}(ppp) \\rightarrow ^{13}\\text{C} π^+ π^+ e^+$, obtained from a search conducted using the Super-Kamiokande detector with 0.401 megaton-years of exposure across five operational periods (SK-I: 1996--2001, SK-II: 2002--2005, SK-III: 2006--2008, SK-IV: 2008--2018, SK-V: 2019--2020). This represents an improvement of six orders of magnitude over previous experimental constraints. The analysis utilizes a convolutional neural network (CNN) incorporating an attention mechanism---a computational technique that enables the model to focus on the most relevant regions of Cherenkov ring patterns---to enhance event classification, thereby improving the sensitivity of the search. This is the first application of a CNN to a nucleon decay search in Super-Kamiokande. Furthermore, the large dataset available in Super-Kamiokande (hereafter \"SK\") strengthens the statistical power of the study, enabling a more stringent constraint than those set by prior experiments.",
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  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.25681",
  "author_total": 299,
  "authors": [
    {
      "name": "J Feng"
    },
    {
      "name": "K Abe"
    },
    {
      "name": "Y Asaoka"
    },
    {
      "name": "M Harada"
    },
    {
      "name": "Y Hayato"
    },
    {
      "name": "K Hiraide"
    },
    {
      "name": "T.H Hung"
    },
    {
      "name": "K Ieki"
    },
    {
      "name": "M Ikeda"
    },
    {
      "name": "J Kameda"
    },
    {
      "name": "Y Kataoka"
    },
    {
      "name": "S Mine"
    },
    {
      "name": "M Miura"
    },
    {
      "name": "S Moriyama"
    },
    {
      "name": "K Nakagiri"
    },
    {
      "name": "M Nakahata"
    },
    {
      "name": "S Nakayama"
    },
    {
      "name": "Y Noguchi"
    },
    {
      "name": "G Pronost"
    },
    {
      "name": "K Sato"
    },
    {
      "name": "H Sekiya"
    },
    {
      "name": "R Shinoda"
    },
    {
      "name": "M Shiozawa"
    },
    {
      "name": "Y Suzuki"
    },
    {
      "name": "A Takeda"
    },
    {
      "name": "Y Takemoto"
    },
    {
      "name": "H Tanaka"
    },
    {
      "name": "S Chen"
    },
    {
      "name": "Y Itow"
    },
    {
      "name": "T Kajita"
    },
    {
      "name": "R Nishijima"
    },
    {
      "name": "K Okumura"
    },
    {
      "name": "T Tashiro"
    },
    {
      "name": "T Tomiya"
    },
    {
      "name": "X Wang"
    },
    {
      "name": "F.J de Garay Arcones"
    },
    {
      "name": "P Fernandez"
    },
    {
      "name": "L Labarga"
    },
    {
      "name": "D Samudio"
    },
    {
      "name": "C Yanagisawa"
    },
    {
      "name": "B Jargowsky"
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    {
      "name": "E Kearns"
    },
    {
      "name": "J Mirabito"
    },
    {
      "name": "L Wan"
    },
    {
      "name": "T Wester"
    },
    {
      "name": "B.W Pointon"
    },
    {
      "name": "J Bian"
    },
    {
      "name": "B Cortez"
    },
    {
      "name": "N.J Griskevich"
    },
    {
      "name": "Y Jiang"
    },
    {
      "name": "M.B Smy"
    },
    {
      "name": "H.W Sobel"
    },
    {
      "name": "V Takhistov"
    },
    {
      "name": "J Hill"
    },
    {
      "name": "B.D Xu"
    },
    {
      "name": "D Jung"
    },
    {
      "name": "D.H Moon"
    },
    {
      "name": "R.G Park"
    },
    {
      "name": "B.S Yang"
    },
    {
      "name": "K Scholberg"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/anaj6yf8hf0xp.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.25681",
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  "openalex": "W7214104955",
  "pdf_url": "https://arxiv.org/pdf/2609.25681",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-26",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/anaj6yf8hf0xp.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:48Z",
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      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.25681"
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  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:hep-ex",
      "subfield": "high-energy"
    }
  ],
  "title": "Search for the $^{16}\\text{O}(ppp) \\rightarrow ^{13}\\text{C} π^+ π^+ e^+$ Decay Mode in Super-Kamiokande Using Machine Learning Techniques",
  "title_text": "Search for the ^16O(ppp) → ^13C π^+ π^+ e^+ Decay Mode in Super-Kamiokande Using Machine Learning Techniques",
  "type": "preprint",
  "updated_at": "2026-10-30T12:25:12Z",
  "url": "https://research.draconitic.com/paper/anaj6yf8hf0xp",
  "venue": "HAL",
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