{"paper":{"title":"Double-polarization observable G in neutral-pion photoproduction off the proton","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"nucl-ex","authors_text":"A. Gridnev, A. Sarantsev, A. Thiel, A.V. Anisovich, A. Wilson, A. Winnebeck, B. Bantes, B. Krusche, Ch. Funke, Ch. Hammann, Ch. Honisch, Ch. Schmidt, Ch. Wendel, D. Bayadilov, D. Elsner, D. Hammann, D. Kaiser, D. Piontek, D. Walther, E. Gutz, E. Klempt, F. Afzal, F. Frommberger, F. Kalischewski, F. Klein, G. Reicherz, H. Dutz, H. Eberhardt, H. Kalinowsky, H. Schmieden, H. van Pee, I. Keshelashvili, I. Lopatin, J. Hannappel, J. Hartmann, J. M\\\"uller, J. M\\\"ullers, K. Fornet-Ponse, K. Koop, K. Makonyi, K. Spieker, K.-T. Brinkmann, L. Witthauer, M. Bichow, M. Dieterle, M. Gottschall, M. Gr\\\"uner, M. Kube, M. Lang, M. Nanova, M. Urban, Ph. Hoffmeister, Ph. Mahlberg, P. Klassen, R. Beck, R. Ewald, S. B\\\"ose, S. Kammer, S. Reeve, S. Runkel, St. Friedrich, St. Goertz, T. Jude, T. Seifen, U. Thoma, V. Crede, V. Kleber, V. Metag, V. Nikonov, V. Sokhoyan, W. Hillert, W. Meyer","submitted_at":"2016-04-11T12:48:33Z","abstract_excerpt":"This paper reports on a measurement of the double-polarization observable G in $\\pi^0$ photoproduction off the proton using the CBELSA/TAPS experiment at the ELSA accelerator in Bonn. The observable G is determined from reactions of linearly-polarized photons with longitudinally-polarized protons. The polarized photons are produced by bremsstrahlung off a properly oriented diamond radiator. A frozen spin butanol target provides the polarized protons. The data cover the photon energy range from 617 to 1325 MeV and a wide angular range. The experimental results for G are compared to predictions "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1604.02922","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":""},"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"}