{"paper":{"title":"Test of low-energy theorems for p(\\vec{gamma},\\pi^{0})p in the threshold region","license":"","headline":"","cross_cats":["hep-ex","hep-ph","nucl-th"],"primary_cat":"nucl-ex","authors_text":"A.M. Bernstein, A. Schmidt, B. Krusche, F. Rambo, F. Wissmann, H.J. Arends, H. Stroeher, I.J.D. MacGregor, J. Ahrens, J.C. McGeorge, J. Weiss, M. Kotulla, M. Wolf, P. Achenbach, R. Beck, R. Leukel, Th. Walcher, U. Siodlaczek, V. Hejny, V. Kuhr, V. Metag, V.M. Olmos de Leon","submitted_at":"2001-05-17T15:33:21Z","abstract_excerpt":"The photon asymmetry in the reaction p(\\vec{\\gamma},\\pi^{0})p close to threshold has been measured for the first time with the photon spectrometer TAPS using linearly polarized photons from the tagged-photon facility at the Mainz Microtron MAMI. The total and differential cross sections were also measured simultaneously with the photon asymmetry. This allowed determination of the S-wave and all three P-wave amplitudes. The low-energy theorems based on the parameter-free third-order calculations of heavy-baryon chiral perturbation theory for P1 and P2 agree with the experimental values."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"nucl-ex/0105010","kind":"arxiv","version":1},"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/nucl-ex/0105010/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"}