{"paper":{"title":"Precise measurement of parity violation in polarized muon decay","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"hep-ex","authors_text":"A. Gaponenko, A. Grossheim, A. Hillairet, A. Olin, B. Shin, C.A. Gagliardi, D.D. Koetke, D.R. Gill, E.L. Mathie, G.M. Marshall, G. Sheffer, J. Hu, J.-M. Poutissou, K. Olchanski, M.D. Hasinoff, P. Depommier, P. Gumplinger, R. Bayes, R.E. Mischke, R.E. Tribble, R. Openshaw, R.P. MacDonald, R. Poutissou, R.S. Henderson, R. Tacik, T.D.S. Stanislaus, TWIST Collaboration: J.F. Bueno, V. Selivanov, W. Faszer, Yu.I. Davydov","submitted_at":"2011-04-19T04:09:23Z","abstract_excerpt":"We present a new high precision measurement of parity violation in the weak interaction, using polarized muon decay. The TWIST collaboration has measured $P_\\mu^\\pi \\xi$, where $P_\\mu^\\pi$ is the polarization of the muon in pion decay and $\\xi$ describes the intrinsic asymmetry in muon decay. We find $P_\\mu^\\pi \\xi = 1.00084 \\pm 0.00029\\,(\\textrm{stat.})_{-0.00063}^{+0.00165}\\,(\\textrm{syst.})$, in good agreement with the standard model prediction of $P_\\mu^\\pi=\\xi=1$. Our result is a factor of 7 more precise than the pre-TWIST value, setting new limits in left-right symmetric electroweak exte"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1104.3632","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"}