{
  "abstract": "Using a dataset of 7.33 fb$^{-1}$ of $e^+ e^-$ annihilation data collected with the BESIII detector at center-of-mass energies from 4.128 to 4.226 GeV, we report an updated measurement of the branching fraction of $D_s^+ \\to τ^+ ν_τ$ via four $τ^+$ decay modes: $τ^+ \\to e^+ ν_e \\barν_τ$, $μ^+ ν_μ \\barν_τ$, $π^+\\barν_τ$, and $π^+ π^{0} \\barν_τ$. The branching fraction is determined to be $\\mathcal{B}({D_s^+ \\to τ^+ ν_τ}) = (5.37 \\pm 0.08_{\\rm stat} \\pm 0.06_{\\rm syst})$ %. The product of the modulus of the Cabibbo-Kobayashi-Maskawa matrix element $|V_{cs}|$ and the $D_s^+$ decay constant $f_{D_s^+}$ is measured to be $f_{D_s^+} |V_{cs}| = (248.2 \\pm 1.9_{\\rm stat} \\pm 1.4_{\\rm syst} \\pm 0.6_{\\rm input} \\pm 0.8_{\\rm EM})$ MeV. Both the branching fraction and the product $f_{D_s^+} |V_{cs}|$ are the most precise results yet obtained. Then, taking $f_{D_s^+}$ from lattice quantum chromodynamics calculations results in $|V_{cs}| = 0.993 \\pm 0.008_{\\rm stat} \\pm 0.006_{\\rm syst} \\pm 0.003_{\\rm input} \\pm 0.003_{\\rm EM}$. Conversely, one finds $f_{D_s^+} = (255.0 \\pm 1.9_{\\rm stat} \\pm 1.4_{\\rm syst} \\pm 0.6_{\\rm input} \\pm 0.8_{\\rm EM})$ MeV when taking $|V_{cs}|$ from the CKMfitter group as an input. Combining with the world average value of $D_s^+ \\to μ^+ ν_μ$, the ratio of the branching fractions between $D_s^+ \\to τ^+ ν_τ$ and $D_s^+ \\to μ^+ ν_μ$ is estimated to be $10.04 \\pm 0.29$, which is consistent with the Standard Model prediction of lepton flavor universality.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": "Journal reference: Phys.Rev.D 114, 033004 (2026)",
  "arxiv": "2606.11593",
  "author_total": 730,
  "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": "Y. H. An"
    },
    {
      "name": "Y. Bai"
    },
    {
      "name": "O. Bakina"
    },
    {
      "name": "Y. Ban"
    },
    {
      "name": "H. -R. Bao"
    },
    {
      "name": "X. L. Bao"
    },
    {
      "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": "H. Cai"
    },
    {
      "name": "M. H. Cai"
    },
    {
      "name": "X. Cai"
    },
    {
      "name": "A. Calcaterra"
    },
    {
      "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"
    },
    {
      "name": "G. Cibinetto"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/3z7snhrtxezgt.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2606.11593",
  "fulltext_url": null,
  "id": "3z7snhrtxezgt",
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  "landing_url": "https://arxiv.org/abs/2606.11593",
  "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"
    ]
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  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2606.11593",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-05",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/3z7snhrtxezgt.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:27:01Z",
      "native_id": "2606.11593",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2606.11593"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:hep-ex",
      "subfield": "high-energy"
    }
  ],
  "title": "Updated measurement of the branching fraction of $D_s^+ \\to τ^+ ν_τ$",
  "title_text": "Updated measurement of the branching fraction of D_s^+ → τ^+ ν_τ",
  "type": "preprint",
  "updated_at": "2026-10-30T12:27:01Z",
  "url": "https://research.draconitic.com/paper/3z7snhrtxezgt",
  "venue": "arXiv",
  "versions": [
    {
      "doi": "10.1103/r7fj-26j2",
      "pid": null,
      "relation": "published-as",
      "title": null,
      "venue": null
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}