{"paper":{"title":"Measurement of the Slope Parameter $\\alpha$ for the $\\eta\\to 3\\pi^0$ decay with the Crystal Ball detector at the Mainz Microtron (MAMI-C)","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"hep-ex","authors_text":"A. Braghieri, A. Koulbardis, A. Nikolaev, A. Polonski, A. Starostin, A. Thomas, B. Boillat, B. Krusche, B. M. K. Nefkens, C. M. Tarbert, D. Branford, D. Hornidge, D. I. Glazier, D. I. Sober, D. Krambrich, D. Mekterovic, D. M. Manley, D. P. Watts, E. F. McNicoll, E. Heid, E. J. Downie, F. Pheron, F. Zehr, G. Rosner, H. Berghauser, H. J. Arends, I. J. D. MacGregor, I. M. Suarez, I. Supek, I. Zamboni, J. Brudvik, J. C. McGeorge, J. D. Kellie, J. R. M. Annand, J. Robinson, K. Bantawa, K. Livingston, L. K. Akasoy, L. V. Fil'kov, M. H. Sikora, M. Korolija, M. Kotulla, M. Lang, M. Martinez, M. Ostrick, M. Rost, M. Thiel, M. Unverzagt, O. Jahn, P. Aguar-Bartolome, P. B. Otte, P. Drexler, P. Pedroni, R. Beck, R. F. B. Codling, R. Gregor, R. Kondratiev, R. Novotny, S. Cherepnya, S. Kruglov, S. Micanovic, S. Prakhov, S. Schumann, T. C. Jude, T. Rostomyan, V. Bekrenev, V. Lisin, V. L. Kashevarov, V. Metag, W. J. Briscoe, Y. Maghrbi","submitted_at":"2008-12-10T19:27:11Z","abstract_excerpt":"The dynamics of the $\\eta\\to 3\\pi^0$ decay have been studied with the Crystal Ball multiphoton spectrometer and the TAPS calorimeter. Bremsstrahlung photons produced by the 1.5-GeV electron beam of the Mainz microtron MAMI-C and tagged by the Glasgow photon spectrometer were used for $\\eta$-meson production. The analysis of $3 \\times 10^6$ $\\gamma p \\to \\eta p \\to 3\\pi^0 p \\to 6\\gamma p$ events yields the value $\\alpha=-0.032\\pm0.003$ for the $\\eta\\to 3\\pi^0$ slope parameter, which agrees with the majority of recent experimental results and has the smallest uncertainty. The $\\pi^0\\pi^0$ invari"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"0812.1999","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"}