{"paper":{"title":"Improved $\\alpha^4$ Term of the Muon Anomalous Magnetic Moment","license":"","headline":"","cross_cats":[],"primary_cat":"hep-ph","authors_text":"M. Nio, T. Kinoshita","submitted_at":"2004-02-19T06:54:36Z","abstract_excerpt":"We have completed the evaluation of all mass-dependent $\\alpha^4$ QED contributions to the muon $g-2$, or $a_\\mu$, in two or more different formulations. Their numerical values have been greatly improved by an extensive computer calculation. The new value of the dominant $\\alpha^4$ term $A_2^{(8)} (m_\\mu / m_e) $ is 132.6823 (72), which supersedes the old value 127.50 (41). The new value of the three-mass term $A_3^{(8)} (m_\\mu / m_e, m_\\mu / m_\\tau) $ is 0.0376 (1). The term $A_2^{(8)} (m_\\mu / m_\\tau) $ is crudely estimated to be about 0.005 and may be ignored for now. The total QED contribu"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"hep-ph/0402206","kind":"arxiv","version":4},"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/hep-ph/0402206/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"}