{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"18cd9aa520577c11c7eb76fad1df9174fdf4933832a92e241b0460e0accdf29d","created":"2026-10-03T07:18:07Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"11237ca8c045af0effc908ffe9c171eb341cd9997941cb64b65b703063daae0d","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"value","assisted_by":[],"external_id":"nuc.emc-src.gluon-emc","kind":"well-posed","literature_status":"open","n":"1","parents":[],"plain":"The EMC effect was seen for quarks, but gluons inside nuclei may also be modified. Present data barely constrain gluons carrying more than 10 percent of a nucleon's momentum.","posed_since":"","precise":"Determine the ratio $g_A(x, Q^{2})/g_N(x, Q^{2})$ of the gluon distribution per nucleon in heavy nuclei to that in free nucleons for $0.1 < x < 0.6$ at $Q^{2} = 10\\,\\mathrm{GeV}^{2}$ with uncertainty below 10 percent. Answer: presence and size of a gluon EMC effect.","problem_ref":null,"references":"","settled_by":"EIC measurements of charm production and the longitudinal structure function $F_{L}$ in electron-nucleus collisions, entered in nuclear parton-distribution fits.","status_note":"","title":"Nuclear modification of gluons at large momentum fraction","topic_ref":"7a074c9c279467b77e19375da4dad17647254ffcdf3c39de667bd47e1e1c500e"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"4719d917c95fe05bd4dba179fd7ae3f0f3aa8c5a2e712bb9aa84525dc4771c58","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"50948af8302199b8dda9f12dcba6b11cf8720841d19d3b81e66809796471346f","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"ToBhUuUzNWleb4qaURycEDu34KwnZTMZptuiFgtgoogxXBnt92RpUHycaN-neAJPO511HkU03-IU_4UNJ2NHBA"},"schema":"pubphys.envelope/1"},"record_hash":"4719d917c95fe05bd4dba179fd7ae3f0f3aa8c5a2e712bb9aa84525dc4771c58","leaf_index":1742}