{"paper":{"title":"Two-Pion Production in Nucleon-Nucleon Collisions and the ABC-Effect - Approaching a Puzzleby exclusive and Kinematically complete Measurements","license":"","headline":"","cross_cats":[],"primary_cat":"nucl-ex","authors_text":"A. Kupsc, A. Kuznetsov, A. Povtorejko, A. Pricking, A. Turowiecki, A. Yamamoto, B. Martemyanov, B. Morosov, B. Shwartz, C. Bargholtz, C. Ekstrom, C. Pauly, D. Bogoslawsky, D. Duniec, E. Doroshkevich, E. Jiganov, F. Cappellaro, F. Kren, G. Ivanov, G. J. Wagner, H. Calen, H. Clement, H. Pettersson, I. Koch, I. Zartova, J. Stepaniak, J. Zabierowski, J. Zlomanczuk, K. Fransson, K. Lindberg, K. Schonning, L. Demiroers, L. Geren, L. Gustafsson. B. Hoistad, l M. Jacewicz, M.Bashkanov, M. Kaskulov, M. Wolke, O. Khakimova, P.-E. Tegner, P. Marciniewski, P. Thorngren-Engholm, R. J. M. Y. Ruber, R. Meier, S. Keleta, S. Kullander, T. Johansson, T. Skorodko, V. Sopov, V. Tikhomirov, W. Oelert, W. Scobel, Y. Petukhov","submitted_at":"2006-12-11T16:33:16Z","abstract_excerpt":"The ABC effect - a puzzling low-mass enhancement in the $\\pi\\pi$ invariant mass spectrum - is known from inclusive measurements of two-pion production in nuclear collisions, where it always showed up, if the participating nucleons fused to a bound nuclear system in the final state. The first exclusive measurements on the ABC effect have been carried out very recently at CELSIUS-WASA for the fusion reactions leading to d, $^3$He and $^4$He nuclei in the final state. The data analyzed so far for the fusion processes to d and $^3$He reveal this effect to be a $\\sigma$ channel phenomenon associate"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"nucl-ex/0612016","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/0612016/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"}