{
  "annotation_id": "ca29f8f9-ea8e-43ba-8af6-a999672ab265",
  "date_created": "2026-03-02T18:00:15.542000Z",
  "date_modified": "2026-03-02T18:00:15.542000Z",
  "file_hash": "bbf0c2f1d230109a24d69839a424d43b74f80fe52befede6b8daea6d07d751af",
  "private": false,
  "record": {
    "abstract": "From the new Mainz data of eta photoproduction off protons\\cite{ref1} and\ndeuterons\\cite{ref2}, we can extract, via the effective Lagrangian approach\n(ELA)\\cite{ref3}, the electrostrong parameters $\\xi_{p}$ and $\\xi_{n}$ for the\nN$^*$(1535) excitation. These parameters are, in units of $10^{-4} MeV^{-1}$,\n$(2.20\\pm 0.15)$ and $(-1.86\\pm 0.20)$ respectively. They yield the ratio of\nthe helicity amplitudes for the excitation of N$^*$(1535) by photons off\nneutrons and protons to be $A^{n}_{1/2}/A^{p}_{1/2}=-0.84\\pm 0.15$, a quantity\nof fundamental importance in the baryon structure. Best estimates in the quark\nmodel are close to this ratio.",
    "arxiv_id": "nucl-th/9511001",
    "authors": [
      "Nimai C. Mukhopadhyay",
      "J. -F. Zhang",
      "M. Benmerrouche"
    ],
    "categories": [
      "nucl-th",
      "hep-ph"
    ],
    "title": "Photoproduction of Etas and N$^*$(1535) Electrostrong Properties",
    "url": "https://arxiv.org/abs/nucl-th/9511001"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "60b0b24a-87c1-4a34-8cd2-2b776bf4071a",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}