{
  "abstract": "Utilizing $(2712.4 {\\pm} 14.3)\\times10^{6}~ψ(3686)$ events collected by the BESIII detector at the symmetric $e^+ e^-$ collider BEPCII, we report the first observation of the electromagnetic Dalitz decay $ψ(3686) \\to μ^+ μ^-η^{\\prime} $ with a statistical significance of 6.1$σ$. The branching fraction is determined to be $\\mathcal{B}(ψ(3686) \\to μ^+ μ^- η^{\\prime})=(4.1 \\pm 1.0_{\\rm stat.} \\pm 0.4_{\\rm syst.})\\times 10^{-7}$. The ratio to the branching fraction of the radiative decay $ψ(3686) \\to γη^{\\prime}$ is estimated to be $(3.3\\pm0.9)\\times10^{-3}$, which is consistent with the prediction of the vector meson dominance model within $1σ$. Furthermore, using the branching fraction of $ψ(3686) \\to e^+ e^- η^{\\prime}$ previously measured by the BESIII experiment, the ratio between the muon and the electron channels is evaluated to be $0.22\\pm0.07$, which is consistent with the calculation of the vector meson dominance model within $1σ$, and no significant violation of lepton flavor universality is found.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.07054",
  "author_total": 781,
  "authors": [
    {
      "name": "BESIII Collaboration"
    },
    {
      "name": "M. Ablikim"
    },
    {
      "name": "M. N. Achasov"
    },
    {
      "name": "P. Adlarson"
    },
    {
      "name": "X. C. Ai"
    },
    {
      "name": "C. S. Akondi"
    },
    {
      "name": "R. Aliberti"
    },
    {
      "name": "A. Amoroso"
    },
    {
      "name": "Q. An"
    },
    {
      "name": "M. S. Anderson"
    },
    {
      "name": "Y. Bai"
    },
    {
      "name": "O. Bakina"
    },
    {
      "name": "H. R. Bao"
    },
    {
      "name": "X. L. Bao"
    },
    {
      "name": "M. Barbagiovanni"
    },
    {
      "name": "V. Batozskaya"
    },
    {
      "name": "K. Begzsuren"
    },
    {
      "name": "N. Berger"
    },
    {
      "name": "M. Berlowski"
    },
    {
      "name": "M. B. Bertani"
    },
    {
      "name": "D. Bettoni"
    },
    {
      "name": "F. Bianchi"
    },
    {
      "name": "E. Bianco"
    },
    {
      "name": "A. Bortone"
    },
    {
      "name": "I. Boyko"
    },
    {
      "name": "R. A. Briere"
    },
    {
      "name": "A. Brueggemann"
    },
    {
      "name": "D. Cabiati"
    },
    {
      "name": "H. Cai"
    },
    {
      "name": "M. H. Cai"
    },
    {
      "name": "X. Cai"
    },
    {
      "name": "X. K. Cai"
    },
    {
      "name": "G. F. Cao"
    },
    {
      "name": "N. Cao"
    },
    {
      "name": "S. A. Cetin"
    },
    {
      "name": "X. Y. Chai"
    },
    {
      "name": "J. F. Chang"
    },
    {
      "name": "T. T. Chang"
    },
    {
      "name": "G. R. Che"
    },
    {
      "name": "Y. Z. Che"
    },
    {
      "name": "C. H. Chen"
    },
    {
      "name": "Chao Chen"
    },
    {
      "name": "G. Chen"
    },
    {
      "name": "H. S. Chen"
    },
    {
      "name": "H. Y. Chen"
    },
    {
      "name": "M. L. Chen"
    },
    {
      "name": "S. J. Chen"
    },
    {
      "name": "S. M. Chen"
    },
    {
      "name": "T. Chen"
    },
    {
      "name": "W. Chen"
    },
    {
      "name": "X. R. Chen"
    },
    {
      "name": "X. T. Chen"
    },
    {
      "name": "X. Y. Chen"
    },
    {
      "name": "Y. B. Chen"
    },
    {
      "name": "Y. Q. Chen"
    },
    {
      "name": "Z. K. Chen"
    },
    {
      "name": "J. Cheng"
    },
    {
      "name": "L. N. Cheng"
    },
    {
      "name": "S. K. Choi"
    },
    {
      "name": "X. Chu"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/dvthg1y8pxhd1.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.07054",
  "fulltext_url": null,
  "id": "dvthg1y8pxhd1",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.07054",
  "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",
      "3106|Quantum Chromodynamics and Particle Interactions"
    ]
  ],
  "openalex": "W7220955880",
  "pdf_url": "https://arxiv.org/pdf/2610.07054",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-05",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/dvthg1y8pxhd1.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:27:22Z",
      "native_id": "2610.07054",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.07054"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:hep-ex",
      "subfield": "high-energy"
    }
  ],
  "title": "First observation of the electromagnetic Dalitz decay $ψ(3686) \\rightarrow μ^+ μ^- η^\\prime$",
  "title_text": "First observation of the electromagnetic Dalitz decay ψ(3686) → μ^+ μ^- η^′",
  "type": "preprint",
  "updated_at": "2026-10-30T12:27:22Z",
  "url": "https://research.draconitic.com/paper/dvthg1y8pxhd1",
  "venue": "arXiv",
  "versions": []
}