{"paper":{"title":"Diffractive $J/\\psi$ photoproduction as a probe of the gluon density","license":"","headline":"","cross_cats":[],"primary_cat":"hep-ph","authors_text":"A.D. Martin, E.M. Levin, M.G. Ryskin, R.G. Roberts","submitted_at":"1995-11-03T16:40:40Z","abstract_excerpt":"We use perturbative QCD, beyond the leading $\\ln Q^2$ approximation, to show how measurements of diffractive $J/\\psi$ production at HERA can provide a sensitive probe of the gluon density of the proton at small values of Bjorken $x$. We estimate both the effect of the relativistic motion of the $c$ and $\\overline{c}$ within the $J/\\psi$ and of the rescattering of the $c\\overline{c}$ quark pair on the proton. We find that the available data for diffractive $J/\\psi$ photoproduction can discriminate between the gluon distributions of the most recent sets of partons."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"hep-ph/9511228","kind":"arxiv","version":2},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/hep-ph/9511228/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}