{
  "abstract": "A bstract : In this work, we compute the next-to-next-to-leading-order (NNLO) QCD corrections to the process e ⁺ e ⁻ → J / ψ + χ cJ at B factories within the NRQCD factorization framework. The helicity amplitudes are obtained via asymptotic expansions around r = 0 and r = 1, with $$r=16{m}_{c}^{2}/s$$ . Our asymptotic expressions reproduce the exact numerical results with high accuracy across the kinematic range 0 ≤ r ≤ 1, achieving a relative error below 10 ⁻⁵ , which is sufficient for phenomenological applications. Notably, the large logarithmic terms are obtained analytically, and the explicit expressions established in this work provide a useful basis for further theoretical investigations.\n\nWe compute the unpolarized cross sections. The $$\\mathcal{O}\\left({\\alpha}_{s}\\right)$$ correction is found to be large, while the $$\\mathcal{O}\\left({\\alpha}_{s}^{2}\\right)$$ correction for χ c 0 production amounts to 33% of the leading-order (LO) cross section, significantly reducing the scale uncertainties. For χ c 1 , the $$\\mathcal{O}\\left({\\alpha}_{s}\\right)$$ and $$\\mathcal{O}\\left({\\alpha}_{s}^{2}\\right)$$ corrections correspond to 35% and − 15%, respectively. For χ c 2 , the corresponding corrections are 24% and − 38%. The large cancellation between the corrections for χ c 2 brings the NNLO cross section close to the LO prediction. Our prediction for χ c 0 is consistent with both the Belle and BaBar data within uncertainties.\n\nWe also predict the angular distribution parameters $${\\alpha}_{\\theta }^{J}$$ , which are independent of nonperturbative inputs. A sharp discrepancy between the theory and the Belle measurement is observed for $${\\alpha}_{\\theta }^{0}$$ , calling for further experimental and theoretical investigations. Moreover, future measurements of the angular distribution parameters for χ c 1 and χ c 2 will provide important tests of the theoretical framework.",
  "abstract_shown": true,
  "affiliations": [
    "Southwest University"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 3,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Hao-Yang Liu",
      "orcid": "0009-0000-8481-5802"
    },
    {
      "affs": [
        0
      ],
      "name": "Cong Li",
      "orcid": "0009-0009-2867-2419"
    },
    {
      "affs": [
        0
      ],
      "name": "Wen-Long Sang",
      "orcid": "0000-0002-8351-9603"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/8e5d2jjakrdt3.bib",
  "cited_by": 0,
  "doi": "10.1007/jhep10(2026)004",
  "fulltext_url": null,
  "id": "8e5d2jjakrdt3",
  "issns": [
    "1029-8479"
  ],
  "landing_url": "https://link.springer.com/10.1007/JHEP10(2026)004",
  "language": null,
  "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": [
    [
      "openalex",
      "3106|Quantum Chromodynamics and Particle Interactions"
    ]
  ],
  "openalex": "W7163136458",
  "pdf_url": "https://link.springer.com/content/pdf/10.1007/JHEP10(2026)004.pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-01",
  "publisher": "Springer Science and Business Media LLC",
  "ris": "https://research.draconitic.com/paper/8e5d2jjakrdt3.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:18:01Z",
      "native_id": "10.1007/jhep10(2026)004",
      "source": "crossref",
      "url": "https://link.springer.com/10.1007/JHEP10(2026)004"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "openalex:3106|Quantum Chromodynamics and Particle Interactions",
      "subfield": "high-energy"
    }
  ],
  "title": "Semi-analytical two-loop QCD corrections to e+e− → J/ψ + χcJ at B factories",
  "title_text": "Semi-analytical two-loop QCD corrections to e+e− → J/ψ + χcJ at B factories",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:18:01Z",
  "url": "https://research.draconitic.com/paper/8e5d2jjakrdt3",
  "venue": "Journal of High Energy Physics",
  "versions": []
}