{"paper":{"title":"Measurement of the Positive Muon Lifetime and Determination of the Fermi Constant to Part-per-Million Precision","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["nucl-ex"],"primary_cat":"hep-ex","authors_text":"A. Gafarov, B. Johnson, B. Kiburg, B. Lauss, B.L. Roberts, B. Wolfe, C.J.G. Onderwater, D.B. Chitwood, D.M. Webber, D.W. Hertzog, F.E. Gray, F. Mulhauser, I. Logashenko, J. Crnkovic, J. Kunkle, J. Phillips, J.P. Miller, K. Giovanetti, K.R. Lynch, P. Kammel, P.T. Debevec, P. Winter, Q.~Peng, R.M. Carey, R. McNabb, S. Battu, S. Dhamija, S. Kizilgul, S. Rath, T.P. Gorringe, V. Tishchenko, W. Earle, Z. Hartwig","submitted_at":"2010-10-05T19:29:28Z","abstract_excerpt":"We report a measurement of the positive muon lifetime to a precision of 1.0 parts per million (ppm); it is the most precise particle lifetime ever measured. The experiment used a time-structured, low-energy muon beam and a segmented plastic scintillator array to record more than 2 x 10^{12} decays. Two different stopping target configurations were employed in independent data-taking periods. The combined results give tau_{mu^+}(MuLan) = 2196980.3(2.2) ps, more than 15 times as precise as any previous experiment. The muon lifetime gives the most precise value for the Fermi constant: G_F(MuLan) "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1010.0991","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"}