{
  "abstract": "The scotogenic model generates sub-eV neutrino masses radiatively through small Yukawa couplings $$\\sim \\mathcal {O}(10^{-3})$$ ∼ O ( 10 - 3 ) that also set the decay length of the heavy neutral fermion $$N_2$$ N 2 ; in the compressed regime a separate, much smaller Yukawa entry $$\\sim \\mathcal {O}(10^{-6})$$ ∼ O ( 10 - 6 ) additionally renders the charged scalar $$\\tilde{\\eta }^{\\pm }$$ η ~ ± long-lived. We study the compressed-spectrum regime of its two-inert-doublet variant ( $$\\varDelta M_{\\textrm{comp}}= m_{\\tilde{\\eta }^\\pm }- m_{N_2}\\simeq 200\\,\\text {MeV}$$ Δ M comp = m η ~ ± - m N 2 ≃ 200 MeV ), in which small Yukawa entries render both the charged scalar $$\\tilde{\\eta }^{\\pm }$$ η ~ ± and the heavy neutral fermion $$N_2$$ N 2 long-lived and produce a nested cascade at the High-Luminosity LHC (HL-LHC): $$\\tilde{\\eta }^{\\pm }$$ η ~ ± leaves a disappearing track (DT), decays to an invisible $$N_2$$ N 2 , which travels macroscopically before forming a displaced dilepton vertex (DV). The two slow flights combine into a 4D time-of-flight delay $$\\varDelta t\\sim 200$$ Δ t ∼ 200 – $$800\\,\\text {ps}$$ 800 ps resolvable by the CMS MIP Timing Detector, while the DT-to-DV displacement vector inherits the parent track direction, yielding a spatial back-pointing correlation with no SM analogue. These two handles are expected to suppress the background to $$B\\sim 10^{-5}$$ B ∼ 10 - 5 – $$10^{-3}$$ 10 - 3 events, and the discovery remains $$5\\sigma $$ 5 σ -significant for any background up to $$B\\sim 10$$ B ∼ 10 events. At the benchmark ( $$m_{N_2}=150\\,\\text {GeV}$$ m N 2 = 150 GeV and proper decay lengths $$c\\tau _{\\tilde{\\eta }^\\pm }=300\\,\\text {mm}$$ c τ η ~ ± = 300 mm , $$c\\tau _{N_2}=189\\,\\text {mm}$$ c τ N 2 = 189 mm ) the strategy yields $$N_s\\approx 1212$$ N s ≈ 1212 signal events at $$3000\\,\\text {fb}^{-1}$$ 3000 fb - 1 and establishes sensitivity across $$15\\,\\text {mm}\\lesssim c\\tau _{\\tilde{\\eta }^\\pm }\\lesssim 300\\,\\text {mm}$$ 15 mm ≲ c τ η ~ ± ≲ 300 mm , $$10\\,\\text {mm}\\lesssim c\\tau _{N_2}\\lesssim 1000\\,\\text {mm}$$ 10 mm ≲ c τ N 2 ≲ 1000 mm , a correlated region left uncovered by any standalone DT or DV search. Because the $$N_2$$ N 2 decay length is controlled by the same Yukawa couplings that generate sub-eV neutrino masses, mapping this nested cascade turns the HL-LHC into a direct collider probe of the interaction responsible for neutrino mass.",
  "abstract_shown": true,
  "affiliations": [
    "Institute of High Energy Physics"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 1,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Renjie Wang",
      "orcid": "0000-0002-5059-8456"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/3drb0jxf1gerr.bib",
  "cited_by": 0,
  "doi": "10.1140/epjc/s10052-026-16416-2",
  "fulltext_url": "https://doi.org/10.1140/epjc/s10052-026-16416-2",
  "id": "3drb0jxf1gerr",
  "issns": [
    "1434-6044",
    "1434-6052"
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  "landing_url": "https://link.springer.com/article/10.1140/epjc/s10052-026-16416-2",
  "language": "en",
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0",
  "metadata_licence": null,
  "native_subjects": [
    [
      "lcc",
      "QB460-466"
    ],
    [
      "lcc",
      "QC770-798"
    ],
    [
      "openalex",
      "3106|Particle physics theoretical and experimental studies"
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  "pdf_url": "https://link.springer.com/content/pdf/10.1140/epjc/s10052-026-16416-2.pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-19",
  "publisher": "Springer Science and Business Media LLC",
  "ris": "https://research.draconitic.com/paper/3drb0jxf1gerr.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:18:04Z",
      "native_id": "10.1140/epjc/s10052-026-16416-2",
      "source": "crossref",
      "url": "https://link.springer.com/article/10.1140/epjc/s10052-026-16416-2"
    },
    {
      "first_seen": "2026-10-30T13:46:27Z",
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      "url": "https://doi.org/10.1140/epjc/s10052-026-16416-2"
    }
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  "subjects": [
    {
      "field": "physics",
      "origin": "openalex:3106|Particle physics theoretical and experimental studies",
      "subfield": "high-energy"
    }
  ],
  "title": "Nested disappearing-track plus displaced-vertex topology at the HL-LHC: a dual long-lived-particle signature of the scotogenic model",
  "title_text": "Nested disappearing-track plus displaced-vertex topology at the HL-LHC: a dual long-lived-particle signature of the scotogenic model",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T13:46:27Z",
  "url": "https://research.draconitic.com/paper/3drb0jxf1gerr",
  "venue": "The European Physical Journal C",
  "versions": [
    {
      "doi": "10.48550/arxiv.2609.28334",
      "pid": "9g3mp46w35swy",
      "relation": "preprint",
      "title": "Nested Disappearing-Track plus Displaced-Vertex Topology at the HL-LHC: A Dual Long-Lived-Particle Signature of the Scotogenic Model",
      "venue": "arXiv"
    }
  ]
}