{
  "abstract": "In relativistic heavy-ion collisions, the linear polarization of quasi-real photons can correlate the spin orientation of photon-induced vector mesons with the collision geometry. To explore this sensitivity, we present the first measurement of the decay angular distribution of photon-induced $J/ψ$ with respect to the event plane in heavy-ion collisions with hadronic overlap. The analysis uses Ru+Ru and Zr+Zr collisions at a nucleon--nucleon center-of-mass energy of $\\sqrt{s_{\\mathrm{NN}}}=200$ GeV recorded by STAR. After correcting for the finite event-plane resolution and subtracting the residual hadronic contribution, we extract a negative second-order modulation, $A_2^{\\rm phot} = -0.39 \\pm 0.11~(\\mathrm{stat.}) \\pm 0.04~(\\mathrm{sys.})$, for $|y^{ee}|<0.8$, $p_{\\mathrm T}^{ee}<0.2~\\mathrm{GeV}/c$, and 30--80% centrality. This modulation provides evidence that the $J/ψ$ polarization is correlated with the event plane, as expected for linearly polarized photons. The observed modulation establishes polarized $J/ψ$ photoproduction as a direct probe of the transverse orientation of the initial collision geometry.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.14604",
  "author_total": 1,
  "authors": [
    {
      "name": "STAR Collaboration"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/da150kpt0mkkp.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.14604",
  "fulltext_url": null,
  "id": "da150kpt0mkkp",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.14604",
  "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",
      "nucl-ex"
    ],
    [
      "openalex",
      "3106|High-Energy Particle Collisions Research"
    ]
  ],
  "openalex": "W7213253067",
  "pdf_url": "https://arxiv.org/pdf/2609.14604",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-13",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/da150kpt0mkkp.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:21:25Z",
      "native_id": "2609.14604",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.14604"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:nucl-ex",
      "subfield": "nuclear"
    }
  ],
  "title": "Photon-induced $J/ψ$ as a linearly polarized probe of collision geometry in relativistic heavy-ion collisions",
  "title_text": "Photon-induced J/ψ as a linearly polarized probe of collision geometry in relativistic heavy-ion collisions",
  "type": "preprint",
  "updated_at": "2026-10-30T12:21:25Z",
  "url": "https://research.draconitic.com/paper/da150kpt0mkkp",
  "venue": "arXiv",
  "versions": []
}