{
  "annotation_id": "e654b705-920d-412b-8d22-ce1d0ecaf073",
  "date_created": "2026-03-02T18:00:01.186000Z",
  "date_modified": "2026-03-02T18:00:01.186000Z",
  "file_hash": "5e516cf858af0f63f426316302212e4481d933bd3fe8701972fe9d897bcaf11a",
  "private": false,
  "record": {
    "abstract": "We present a relativistic dynamical model of pion photoproduction on the\nnucleon in the resonance region. It offers several advances over the existing\napproaches. The model is obtained by extending our $\\pi N$-scattering\ndescription to the electromagnetic channels. The resulting photopion amplitude\nis thus unitary in the $\\pi N$, $\\ga N$ channel space, Watson\u0027s theorem is\nexactly satisfied. At this stage we have included the pion, nucleon,\n$\\De(1232)$-resonance degrees of freedom. The $\\rho$ and $\\omega$ meson\nexchanges are also included, but play a minor role in the considered energy\ndomain (up to $\\sqrt{s}=1.5$ GeV). In this energy range the model provides a\ngood description of all the important multipoles. We have allowed for only two\nfree parameters -- the photocouplings of the $\\Delta$-resonance. These\ncouplings are adjusted to reproduce the strength of corresponding\nresonant-multipoles $M_{1+}$ and $E_{1+}$ at the resonance position.",
    "arxiv_id": "nucl-th/0407068",
    "authors": [
      "Vladimir Pascalutsa",
      "John A. Tjon"
    ],
    "categories": [
      "nucl-th",
      "hep-ph"
    ],
    "doi": "10.1103/PhysRevC.70.035209",
    "journal_ref": "Phys.Rev.C70:035209,2004",
    "title": "Pion photoproduction on nucleons in a covariant hadron-exchange model",
    "url": "https://arxiv.org/abs/nucl-th/0407068"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "ffc93948-bfb3-4737-8368-27562886129e",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}