{"paper":{"title":"Measurement of $B^0 \\to J/\\psi \\eta^{(}{}'{}^{)}$ and Constraint on the $\\eta-\\eta'$ Mixing Angle","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"hep-ex","authors_text":"A. Bondar, A. Bozek, A. Chen, A. Drutskoy, A. Garmash, A. Ishikawa, A. J. Schwartz, A. M. Bakich, A. Moll, A. Sibidanov, A. Sokolov, A. Zupanc, B. Bhuyan, B. G. Cheon, B. Golob, B. R. Ko, C. H. Wang, C. Liu, C. P. Shen, C. Schwanda, C. W. Park, C. Z. Yuan, D. M. Asner, E. Nakano, E. Solovieva, E. Won, F. Simon, G. B. Mohanty, G. Pakhlova, G. Tatishvili, G. Varner, H. Aihara, H. Hayashii, H. J. Hyun, H. Miyata, H. Nakazawa, H. O. Kim, H. Sahoo, H. Yamamoto, I. Adachi, I. Nakamura, I.-S. Cho, J. B. Kim, J. Brodzicka, J. Dalseno, J. E. Fast, J.-G. Shiu, J. Haba, J. Li, J. Libby, J. S. Lange, J.-Y. Lin, K. Adamczyk, K. Chilikin, K.-F. Chen, K. Hayasaka, K. Kinoshita, K. Miyabayashi, K. M. Williams, K. Nishimura, K. Sakai, K. Senyo, K. S. Park, K. T. Kim, L. E. Piilonen, M. Bracko, M.-C. Chang, M. E. Sevior, M. Iwabuchi, M. J. Kim, M. Nakao, M. Petric, M. Rohrken, M. Shapkin, M. Staric, M. Sumihama, M. Uchida, M.-Z. Wang, N. Katayama, N. Muramatsu, O. Nitoh, O. Schneider, P. Chang, P. Chen, P. Kodys, P. Krizan, P. Krokovny, P. Smerkol, P. Urquijo, P. Wang, R. Chistov, R. Itoh, R. Kumar, R. Louvot, R. Mizuk, R. Pestotnik, S. Eidelman, S.-H. Lee, S.-K. Choi, S. Koblitz, S. Korpar, S. L. Olsen, S. McOnie, S. Nishida, S. Ogawa, S. Okuno, S. Ryu, S. Stanic, S. Tanaka, S. Uehara, S. Uno, T.-A. Shibata, T. Aushev, T. E. Browder, T. Hara, T. Iijima, T. Iwashita, T. Julius, T. Kawasaki, T. K. Pedlar, T. Kuhr, T. Kumita, T. Ohshima, T. Peng, T. Sumiyoshi, T. Uglov, V. Bhardwaj, V. Gaur, V. Vorobyev, V. Zhilich, V. Zhulanov, W.-S. Hou, Y.-C. Duh, Y. Choi, Y. Horii, Y. Hoshi, Y. Iwasaki, Y. J. Kim, Y.-J. Kwon, Y. Li, Y. M. Goh, Y. Miyazaki, Y. Nagasaka, Y. Sakai, Y.-S. Sohn, Y. Teramoto, Y. Unno, Y. Usov, Y. Watanabe, Y. Yamashita, Y. Yusa, Z. Dolezal, Z. Drasal, Z. Natkaniec, Z. P. Zhang, Z. Q. Liu","submitted_at":"2012-03-15T15:54:11Z","abstract_excerpt":"We measure the branching fractions of $B^{0} \\to J/\\psi \\eta^{(}{}'{}^{)}$ decays with the complete Belle data sample of $772 \\times 10^{6}$ $B\\bar{B}$ events collected at the $\\Upsilon(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^+ e^-$ collider. The results for the branching fractions are: ${\\cal B}(B^{0} \\to J/\\psi \\eta)=(12.3 \\pm ^{1.8}_{1.7} \\pm 0.7) \\times 10^{-6}$ and ${\\cal B}(B^{0} \\to J/\\psi\\eta') < 7.4 \\times 10^{-6}$ at 90% confidence level. The $\\eta-\\eta'$ mixing angle is constrained to be less than $ 42.2^{\\circ}$ at 90% confidence level."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1203.3399","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"}