{"paper":{"title":"First Measurement of the $\\Sigma$ Beam Asymmetry in $\\eta^{\\prime}$ Photoproduction off the Proton near Threshold","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"nucl-ex","authors_text":"A. D'Angelo, A. Fantini, A. Giusa, A. Lapik, A. Lleres, A. Mushkarenkov, A. Turinge, B. Girolami, C. Gaulard, C. Randieri, C. Schaerf, D. Franco, D. Moricciani, D. Rebreyend, F. Curciarello, F. Ghio, F. Mammoliti, G. Gervino, G. Giardina, G. Mandaglio, G. Russo, I. Zonta, J.P. Bocquet, J.P. Didelez, M. Capogni, M.C. Sutera, M.L. Sperduto, M. Manganaro, N. Rudnev, O. Bartalini, P. Levi Sandri, R. Di Salvo, V. Bellini, V. De Leo, V. Nedorezov, V. Vegna","submitted_at":"2014-07-25T18:05:57Z","abstract_excerpt":"The $\\Sigma$ beam asymmetry in $\\eta^{\\prime}$ photoproduction off the proton was measured at the GrAAL polarised photon beam with incoming photon energies of 1.461 and 1.480 GeV. For both energies the asymmetry as a function of the meson production angle shows a clear structure, more pronounced at the lowest one, with a change of sign around 90$^o$. The observed behaviour is compatible with P-wave D-wave (or S-wave F-wave) interference, the closer to threshold the stronger. The results are compared to the existing state-of-the-art calculations that fail to account for the data."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1407.6991","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/1407.6991/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"}