{"paper":{"title":"Measurement of single- and double-polarization observables in the photoproduction of $\\pi^+\\pi^-$~meson pairs off the proton using CLAS at Jefferson Laboratory","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"nucl-ex","authors_text":"A. A. Rusova, A. Bianconi, A. D'Angelo, A. Deur, A. El Alaoui, A. Filippi, A. Hobart, A. I. Ostrovidov, A. Kim, A. Kripko, A. S. Biselli, A. Schmidt, A. V. Sarantsev, B. McKinnon, B. Ritchie, C. Djalali, C. Munoz Camacho, C. Salgado, D. G. Ireland, D. Heddle, D. Jenkins, D. Keller, D. Marchand, D. Martiryan, D. Matamoros, D. Nguyen, D. Protopopescu, D. P. Watts, D. S. Carman, D. Sokhan, E. Klempt, E. L. Isupov, E. Pasyuk, E. Voutier, E. V. Shirokov, F. Benmokhtar, F. Bossu, F. J. Klein, G. Ciullo, G. Gavalian, G. Niculescu, G. Rosner, H. Atac, H. Avakian, H. Egiyan, H. Hakobyan, H. Jiang, H. S. Jo, H. Voskanyan, I. I. Strakovsky, I. J. D. MacGregor, I. P. Fernando, J. A. Tan, J. Price, J. Richards, J. Ritman, J. S. Alvarado, K. Hafidi, K. Joo, K. Livingston, K. Neupane, K.-T. Brinkmann, L. Barion, L. El Fassi, L. Guo, L. Lanza, L. L. Pappalardo, L. Venturelli, L. Xu, M. Bashkanov, M. Battaglieri, M. Bondi, M. Contalbrigo, M. Defurne, M. Dugger, M. E. McCracken, M. Hattawy, M. Holtrop, M. H. Wood, M. Khandaker, M. Osipenko, M. Ouillon, M. Paolone, M. Ripani, M. Spreafico, M. Tenorio, M. Ungaro, M. Zurek, N. A. Baltzell, N. Dashyan, N. Pilleux, N. Sparveris, N. Trotta, N. Zachariou, P. Achenbach, P. Chatagnon, P. Eugenio, P. L. Cole, P. Lenisa, P. Nadel-Turonski, P. Pandey, P. Rossi, P. Roy, R. A. Schumacher, R. Capobianco, R. DeVita, R. Dupre, R. Paremuzyan, R. Tyson, R. W. Gothe, S. Boiarinov, S. Cao, S. Diehl, S. Fegan, S. Joosten, S. J. Paul, S. Polcher Rafael, S. Schadmand, S. Shrestha, S. Strauch, S. Vallarino, T. B. Hayward, T. Cao, T. Mineeva, T. Vittorini, U. Weerasinghe, V. A. Nikonov, V. Crede, V. D. Burkert, V. Klimenko, V. Kubarovsky, V. Mascagna, V. Mokeev, W. J. Briscoe, W. K. Brooks, W. Kim, W. Phelps, W. R. Armstrong, X. Li, X. Wei, Y. G. Sharabian, Y. Ilieva, Y. Prok, Z. W. Zhao","submitted_at":"2025-04-29T18:58:17Z","abstract_excerpt":"The photoproduction of $\\pi^+\\pi^-$ meson pairs off the proton has been studied in the reaction $\\gamma p\\to p\\,\\pi^+\\pi^-$ using the CEBAF Large Acceptance Spectrometer (CLAS) and the frozen-spin target (FROST) in Hall B at the Thomas Jefferson National Accelerator Facility. For the first time, the beam and target asymmetries, $I^{s,c}$ and $P_{x,y}$, have been measured along with the beam-target double-polarization observables, $P^{s,c}_{x,y}$, using a transversely polarized target with center-of-mass energies ranging from 1.51 GeV up to 2.04 GeV. These data and additional $\\pi\\pi$ photoprod"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2504.21119","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/2504.21119/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"}