{
  "annotation_id": "85a8390e-1435-413f-ada0-4e52b329c86f",
  "date_created": "2026-02-17T05:53:20.330000Z",
  "date_modified": "2026-02-17T05:53:20.330000Z",
  "file_hash": "614edd8e545d95c4712cc2ac12d5fec41a77898fc90ee877ec146c0187de1399",
  "private": false,
  "record": {
    "abstract": "We study the near-threshold exclusive photoproduction of heavy vector mesons (quarkonia $J/\\psi$ and $\\Upsilon$) off the proton within the framework of generalized parton distribution (GPD) factorization. The gluon GPDs are computed using a spectator model in which the proton emits a gluon and the remaining constituents are treated as a single spectator particle. Model parameters are determined by fitting the gluon unpolarized and helicity collinear parton distribution functions (PDFs) from global analyses. We compare our results with the latest near-threshold $J/\\psi$ production data from the GlueX and $J/\\psi$-007 experiments at Jefferson Laboratory, finding good agreement for both differential and total cross sections. Predictions are also provided for $\\Upsilon$ photoproduction, which can be tested at future Electron-Ion Colliders.",
    "arxiv_id": "2601.09312",
    "authors": [
      "Chentao Tan",
      "Zhun Lu"
    ],
    "categories": [
      "hep-ph",
      "hep-ex"
    ],
    "license": "http://creativecommons.org/licenses/by-nc-nd/4.0/",
    "title": "Near-threshold photon-proton production of $J/\\psi$ and $\\Upsilon$",
    "url": "https://arxiv.org/abs/2601.09312",
    "version": "v2"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "50106e9a-b8cd-4fbe-a6f2-755a9ae6eae6",
    "id": "arXiv Dataset",
    "type": "Model",
    "variant": "snapshot-2026-01-17",
    "version": "0.1.0"
  },
  "user_id": 1000002
}