{
  "abstract": "We present an updated global analysis of the transverse-momentum-dependent (TMD) helicity distributions of the nucleon from measurements of the longitudinal double-spin asymmetry $A_{LL}$ in semi-inclusive deep-inelastic scattering (SIDIS). The analysis incorporates target- and detected-hadron-mass corrections, next-to-next-to-leading-order matching in the small-$b_T$ operator product expansion, and an improved treatment of correlated systematic uncertainties. The present data constrain the up- and down-quark helicity TMDs, whereas the sea-quark and gluon distributions remain weakly constrained. After integration over transverse momenta up to the hard scale, the up- and down-quark distributions agree with collinear helicity distributions within uncertainties. Using the extracted TMDs and the Wandzura-Wilczek-type approximation, we predict the $\\cosϕ_h$ modulation of $A_{LL}$ and find agreement with the HERMES and CLAS measurements. We also provide predictions for SIDIS $A_{LL}$ at CLAS12 and for longitudinal single-spin asymmetries in $W^\\pm$ production with leptonic decays at STAR kinematics. An impact study with pseudodata for the proposed Electron-Ion Collider in China (EicC) indicates substantial potential to improve constraints on helicity TMDs at intermediate $x$, including the presently weakly constrained sea-quark sector.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.31290",
  "author_total": 6,
  "authors": [
    {
      "name": "Ke Yang"
    },
    {
      "name": "Tianbo Liu"
    },
    {
      "name": "Bo-Qiang Ma"
    },
    {
      "name": "Peng Sun"
    },
    {
      "name": "Yuxiang Zhao"
    },
    {
      "name": "Yiyu Zhou"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/c9tm0gfrxmqb6.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.31290",
  "fulltext_url": null,
  "id": "c9tm0gfrxmqb6",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.31290",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "hep-ph"
    ],
    [
      "openalex",
      "3106|Quantum Chromodynamics and Particle Interactions"
    ]
  ],
  "openalex": "W7223354537",
  "pdf_url": "https://arxiv.org/pdf/2610.31290",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-22",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/c9tm0gfrxmqb6.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:34:34Z",
      "native_id": "2610.31290",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.31290"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:hep-ph",
      "subfield": "high-energy"
    }
  ],
  "title": "Extraction of transverse-momentum-dependent helicity distributions of the nucleon",
  "title_text": "Extraction of transverse-momentum-dependent helicity distributions of the nucleon",
  "type": "preprint",
  "updated_at": "2026-10-30T12:34:34Z",
  "url": "https://research.draconitic.com/paper/c9tm0gfrxmqb6",
  "venue": "arXiv",
  "versions": []
}