{"paper":{"title":"Study of the K0(L) --> pi0 pi0 nu nu-bar decay","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"hep-ex","authors_text":"A. Lednev, A. Moisseenko, A. S. Kurilin, A. Sugiyama, E391a Collaboration: R. Ogata, E. Iwai, E. Kuzmin, G. N. Perdue, G. Y. Lim, H. Ishii, H. Morii, H. Nanjo, H. Okuno, H. Sato, H. S. Lee, H. Watanabe, H. Y. Yoshida, I. Kato, J. Comfort, J. K. Ahn, J. Ma, J. Nix, K. F. Chen, K. Omata, K. Sakashita, M. Doroshenko, M. L. Wu, M. Nomachi, M. Sekimoto, M. Yamaga, N. Ishihara, N. Nishi, N. Sasao, S. Ishibashi, S. Kobayashi, S. Komatsu, S. Perov, S. Podolsky, S. Porokhovoy, S. Suzuki, S. Takita, S. Y. Lee, T. Inagaki, T. Iwata, T. K. Komatsubara, T. Matsumura, T. Morimoto, T. Nakano, T. Nomura, T. Sasaki, T. Sato, T. Shimogawa, T. Shinkawa, T. Sumida, T. Tsukamoto, T. Yamanaka, V. Baranov, Y. Akune, Y. B. Hsiung, Y. C. Tung, Y. Fujioka, Y. Nakajima, Y. Stepanenko, Y. Sugaya, Y. Tajima, Y. W. Wah, Y. Yoshimura, Y. Zheng, Z. Tsamalaidze","submitted_at":"2011-06-17T07:30:38Z","abstract_excerpt":"The rare decay K0(L) --> pi0 pi0 nu nu-bar was studied with the E391a detector at the KEK 12-GeV proton synchrotron. Based on 9.4 x 10^9 K0L decays, an upper limit of 8.1 x 10^{-7} was obtained for the branching fraction at 90% confidence level. We also set a limit on the K0(L) --> pi0 pi0 X (X --> invisible particles) process; the limit on the branching fraction varied from 7.0 x 10^{-7} to 4.0 x 10^{-5} for the mass of X ranging from 50 MeV/c^2 to 200 MeV/c^2."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1106.3404","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"}