{"paper":{"title":"Testing Lepton Flavor Universality and CKM Unitarity with Rare Pion Decays in the PIONEER experiment","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":["hep-ph","physics.ins-det"],"primary_cat":"hep-ex","authors_text":"A. Crivellin, A. Di Canto, A. Gaponenko, A. Garcia, A. Seiden, A. Sher, A. Soter, A. Tricoli, B. Kiburg, B. Schumm, B. Velghe, C. Glaser, C. Malbrunot, C. Polly, C. Zhang, D. Bryman, D. G\\\"oldi, D. Hertzog, D. Po\\v{c}ani\\'c, D. Ries, E. Blucher, E. Worcester, H. Binney, J. LaBounty, J. Mott, J. Ott, K. Labe, K. Pachal, L. Caminada, L. Doria, L. Gibbons, M. Escobar Godoy, M. Hoferichter, M. Tarka, M. Worcester, PIONEER Collaboration: W. Altmannshofer, P. Kammel, P. Schwendimann, R. Mischke, R. Roehnelt, R. Shrock, S. Chen, S. Corrodi, S. Cuen-Rochin, S. Gori, S. Ito, S. Mihara, S.M. Mazza, T. Gorringe, T. Iwamoto, T. Mori, T. Numao, T. Sullivan, U. Langenegger, V. Cirigliano, V. Tischenko, V. Wong, W. Ootani, X. Qian, Z. Hodge","submitted_at":"2022-03-10T17:49:50Z","abstract_excerpt":"The physics motivation and the conceptual design of the PIONEER experiment, a next-generation rare pion decay experiment testing lepton flavor universality and CKM unitarity, are described. Phase I of the PIONEER experiment, which was proposed and approved at Paul Scherrer Institut, aims at measuring the charged-pion branching ratio to electrons vs.\\ muons, $R_{e/\\mu}$, 15 times more precisely than the current experimental result, reaching the precision of the Standard Model (SM) prediction at 1 part in $10^4$. Considering several inconsistencies between the SM predictions and data pointing to"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2203.05505","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/2203.05505/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"}