{"paper":{"title":"Determination of the {\\eta} mass with the Crystal Ball at MAMI-B","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"nucl-ex","authors_text":"A. Braghieri, A. Jankowiak, A. Nikolaev, A. Polonski, A. Reiter, A. Starostin, A. Thomas, B. Boillat, B. Krusche, B. M. K. Nefkens, C. M. Tarbert, D. Branford, D. Hornidge, D. I. Glazier, D. Krambrich, D. Mekterovic, D. M. Manley, D. P. Watts, D. Sober, E. Heid, E. J. Downie, F. Zehr, G. Rosner, H. J. Arends, I. J. D. MacGregor, I. Supek, J. Ahrens, J. C. McGeorge, J. R. M. Annand, J. W. Brudvik, J. W. Price, K.-H. Kaiser, K. Livingston, L. V. Fil'kov, M. Dehn, M. Korolija, M. Kotulla, M. Lang, M. Martinez-Fabregate, M. Rost, M. Unverzagt, O. Jahn, P. Aguar-Bartolom\\'e, P. Pedroni, R. Beck, R. Codling, R. Gregor, R. Kondratiev, R. Novotny, R. O. Owens, S. Cherepnya, S. Lugert, S. N. Prakhov, S. Schumann, Th. Walcher, T. Rostomyan, U. Ludwig-Mertin, V. Bekrenev, V. Lisin, V. L. Kashevarov, V. Metag, W. J. Briscoe","submitted_at":"2012-07-16T15:44:58Z","abstract_excerpt":"A new precise determination of the {\\eta} meson mass is presented. It is based on a measurement of the threshold for the {\\gamma}p -> p{\\eta} reaction using the tagger focal-plane microscope detector at the MAMI-B facility in Mainz. The tagger microscope has a higher energy resolution than the standard tagging spectrometer and, hence, allowed an improvement in the accuracy compared to the previous {\\eta} mass measurement at MAMI-B. The result m{\\eta} = (547.851 +- 0.031 stat. +- 0.062 syst.) MeV agrees very well with the precise values of the NA48, KLOE and CLEO collaborations and deviates by "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1207.3710","kind":"arxiv","version":2},"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"}