{"paper":{"title":"First Measurement of the Polarization Observable E in the $\\vec p(\\vec \\gamma,\\pi^+)n$ Reaction up to 2.25 GeV","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["hep-ex"],"primary_cat":"nucl-ex","authors_text":"A. Celentano, A. D'Angelo, A. Deur, A. El Alaoui, A. Filippi, A. Fradi, A.I. Ostrovidov, A.J.R. Puckett, A. Kim, A. Klein, A Movsisyan, A. Rizzo, A.S. Biselli, A. Simonyan, A. Trivedi, A.V. Anisovich, A.V. Sarantsev, B.A. Raue, B.G. Ritchie, B. McKinnon, B.S. Ishkhanov, C.A. Meyer, C. Carlin, C. Djalali, C.D. Keith, C. Hanretty, C.I. Moody, C. Munoz Camacho, C. Salgado, D. Adikaram, D.G. Ireland, D.G. Meekins, D. Ho, D.I. Glazier, D.I. Sober, D. Jenkins, D. Keller, D. Protopopescu, D.P. Watts, D. R\\\"onchen, D.S. Carman, D. Schott, D. Sokhan, E. De Sanctis, E. Golovatch, E. Klempt, E.L. Isupov, E. Munevar, E. Pasyuk, E. Seder, E. Voutier, F.J. Klein, F. Sabati\\'e, F.X. Girod, G. Charles, G.D. Smith, G. Fedotov, G. Khachatryan, G. Niculescu, G. Rosner, H. Egiyan, H. Hakobyan, H. Jiang, H. Moutarde, H.S. Jo, H. Voskanyan, H.Y. Lu, I. Bedlinskiy, I .J .D. MacGregor, I. Niculescu, I Senderovich, I. Strakovsky, Iu. Skorodumina, I. Zonta (The CLAS collaboration), J.A. Fleming, J. Ball, J. Brock, J.J. Phillips, J.W. Price, J. Zhang, K.A. Griffioen, K. Hafidi, K. Hicks, K. Joo, K.L. Giovanetti, K. Livingston, K.P. Adhikari, K. Park, L.A. Net, L. Colaneri, L. El Fassi, L. Elouadrhiri, L. Guo, L. Zana, M. Battaglieri, M. Contalbrigo, M.D. Anderson, M. D\\\"oring, M. Dugger, M. Guidal, M. Hattawy, M. Holtrop, M.H. Wood, M. Khandaker, M.L. Seely, M. Osipenko, M. Ripani, M. Taiuti, M. Ungaro, N. Benmouna, N. Compton, N. Dashyan, N. Gevorgyan, N. Harrison, N.K. Walford, N. Markov, N. Sparveris, N. Zachariou, O. Cortes, O. Pogorelko, P. Eugenio, P.L. Cole, P. Lenisa, P. Nadel-Turonski, P. Peng, P. Roy, P. Stoler, R.A. Badui, R.A. Montgomery, R.A. Schumacher, R. De Vita, R. Dupre, R. Tucker, R.W. Gothe, R. Workman, S. Anefalos Pereira, S. Chandavar, S.E. Kuhn, S. Fegan, S. Joosten, S.M. Hughes, S. Niccolai, S. Pisano, S. Pozdniakov, S. Procureur, S. Stepanyan, S. Strauch, T.A. Forest, T. Cao, V.A. Nikonov, V. Batourine, V. Crede, V.D. Burkert, V. Kubarovsky, V. Mokeev, V. Sytnik, W. Gohn, W.J. Briscoe, W.K. Brooks, W. Kim, W. Phelps, X. Wei, Ye Tian, Y. Ghandilyan, Y.G. Sharabian, Y. Ilieva, Y. Prok, Z.W. Zhao","submitted_at":"2015-03-17T18:55:17Z","abstract_excerpt":"First results from the longitudinally polarized frozen-spin target (FROST) program are reported. The double-polarization observable E, for the reaction $\\vec \\gamma \\vec p \\to \\pi^+n$, has been measured using a circularly polarized tagged-photon beam, with energies from 0.35 to 2.37 GeV. The final-state pions were detected with the CEBAF Large Acceptance Spectrometer in Hall B at the Thomas Jefferson National Accelerator Facility. These polarization data agree fairly well with previous partial-wave analyses at low photon energies. Over much of the covered energy range, however, significant dev"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1503.05163","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"}