{"paper":{"title":"Color-octet mechanism in $\\gamma + p \\to J/\\psi + X$","license":"","headline":"","cross_cats":[],"primary_cat":"hep-ph","authors_text":"H. S. Song (Seoul National Univ.), Jungil Lee, Pyungwon Ko (Hong-Ik Univ.)","submitted_at":"1996-02-05T11:05:34Z","abstract_excerpt":"Photoproduction of $J/\\psi$ is considered including the color-octet contributions from the various partial wave states, $^{2S+1}L_J$ = $^1S_0$, $^3S_1$ and $^3P_J$. The production cross section depends on three new nonperturbative parameters defined in NRQCD, called the color-octet matrix elements. Using the color-octet matrix elements determined by fitting the $J/\\psi$ production at the Tevatron, we find that the color-octet($c\\bar{c}) _{8}({^1S_0}~{\\rm and~}~{^3P_J})$ contributions to the $J/\\psi$ photoproductions at the fixed target experiments and HERA are too large compared to the data on"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"hep-ph/9602223","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":""},"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"}