{
  "abstract": "The nucleon axial form factor is analyzed in terms of a dispersion relation comprising chiral perturbation theory (ChPT) and perturbative QCD (pQCD) in the low- and high-momentum regimes respectively, which implies a set of superconvergence sum rules for the $A \\to N \\bar N$ spectral function. In the timelike region below the $N \\bar N$ production threshold we include the $a_1$ and $a_1'$ resonances, with finite-width effects modeled through $ρπ$ and $σπ$ intermediate states. Above the $N \\bar N$ threshold, we model an infinite tower of radially excited $1^{++}$ resonances with a non-integer power fall-off, eventually matching pQCD. In this setup, we find that both the ChPT and pQCD contributions are tiny. In turn, the dominant $ρπ$ triangle provides the leading deviations from axial meson dominance. Our calculation is not a fit; it contains parameters with a priori uncertainties estimates. The axial radius is predicted to be $r_A^2 =(0.28-0.33)~\\textrm{fm}^2 = ( 0.47-0.57~\\textrm{fm})^2$ in agreement with recent lattice QCD results but inconsistent with the MINER$ν$A determination. A simple semiempirical formula is provided accounting for the main physical effects.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.05109",
  "author_total": 2,
  "authors": [
    {
      "name": "Enrique Ruiz Arriola"
    },
    {
      "name": "Pablo Sanchez-Puertas"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/dz76f4y8b8dy1.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.05109",
  "fulltext_url": null,
  "id": "dz76f4y8b8dy1",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.05109",
  "language": null,
  "licence": "CC-BY-NC-ND-4.0",
  "licence_label": "CC BY-NC-ND 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by-nc-nd/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "hep-ex"
    ],
    [
      "arxiv",
      "hep-lat"
    ],
    [
      "arxiv",
      "hep-ph"
    ],
    [
      "openalex",
      "3106|Quantum Chromodynamics and Particle Interactions"
    ]
  ],
  "openalex": "W7211899116",
  "pdf_url": "https://arxiv.org/pdf/2609.05109",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-04",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/dz76f4y8b8dy1.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:19:14Z",
      "native_id": "2609.05109",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.05109"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:hep-ex",
      "subfield": "high-energy"
    }
  ],
  "title": "The axial-vector nucleon form factor in the meson dominance picture: the role triangle singularities from a dispersive view",
  "title_text": "The axial-vector nucleon form factor in the meson dominance picture: the role triangle singularities from a dispersive view",
  "type": "preprint",
  "updated_at": "2026-10-30T12:19:14Z",
  "url": "https://research.draconitic.com/paper/dz76f4y8b8dy1",
  "venue": "arXiv",
  "versions": []
}