{"paper":{"title":"Measurement of the beam asymmetry $\\Sigma$ for $\\pi^0$ and $\\eta$ photoproduction on the proton at $E_\\gamma = 9$ GeV","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"nucl-ex","authors_text":"A. Austregesilo, A. Barnes, A. Deur, A. Dolgolenko, A. Gasparian, A. Gerasimov, A. Henderson, A. I. Ostrovidov, A. M. Foda, A. Somov, A. Subedi, A. Teymurazyan, A. Tomaradze, A. Toro, A. Tsaris, A. Yu. Semenov, B. E. Cannon, B. G. Ritchie, B. Pratt, B. Zihlmann, C. A. Meyer, C. Fanelli, C. Kourkoumeli, C. Salgado, C. Schwarz, D. G. Ireland, D. I. Sober, D. Lawrence, D. Mack, D. Romanov, D. W. Bennett, D. Werthmuller, E. Chudakov, E. G. Anassontzis, E. Pooser, E. S. Smith, E. Wolin, F. Barbosa, F. J. Klein, F. Mokaya, F. Nerling, G. J. Lolos, GlueX Collaboration: H. Al Ghoul, G. M. Huber, G. Nigmatkulov, G. Vasileiadis, H. Egiyan, H. Hakobyan, I. A. Semenova, I. I. Strakovsky, I. Kuznetsov, I. Larin, I. Tolstukhin, I. Vega, J. Frye, J. Hardin, J. McIntyre, J. Nys, J. Reinhold, J. R. Stevens, J. Schwiening, J. Zarling, K. Goetzen, K. J. Peters, K. K. Seth, K. Livingston, K. Moriya, L. Gan, L. Guo, L. Pentchev, L. Robison, M. Dugger, M. J. Staib, M. Kamel, M. Lara, M. McCaughan, M. McCracken, M. M. Dalton, M. M. Ito, M. Patsyuk, M. R. Pennington, M. R. Shepherd, M. Williams, N. Gevorgyan, N. K. Walford, N. Ochoa, N. S. Jarvis, N. Sparks, O. Chernyshov, O. Soto, P. Eugenio, P. T. Mattione, R. A. Schumacher, R. Dzhygadlo, R. E. Mitchell, R. Kliemt, R. Mendez, R. Miskimen, R. Pedroni, R. T. Jones, S. Dobbs, S. Furletov, S. Kuleshov, S. Somov, S. Taylor, T. Black, T. D. Beattie, T. Whitlatch, T. Xiao, V. Crede, V. Kakoyan, V. Lyubovitskij, V. Mathieu, V. Matveev, V. S. Goryachev, V. Tarasov, V. V. Berdnikov, W. Boeglin, W. I. Levine, W. J. Briscoe, W. K. Brooks, W. McGinley, Y. Qiang, Z. Papandreou, Z. Zhang","submitted_at":"2017-01-27T17:20:59Z","abstract_excerpt":"We report measurements of the photon beam asymmetry $\\Sigma$ for the reactions $\\vec{\\gamma}p\\to p\\pi^0$ and $\\vec{\\gamma}p\\to p\\eta $ from the GlueX experiment using a 9 GeV linearly-polarized, tagged photon beam incident on a liquid hydrogen target in Jefferson Lab's Hall D. The asymmetries, measured as a function of the proton momentum transfer, possess greater precision than previous $\\pi^0$ measurements and are the first $\\eta$ measurements in this energy regime. The results are compared with theoretical predictions based on $t$-channel, quasi-particle exchange and constrain the axial-vec"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1701.08123","kind":"arxiv","version":4},"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"}