{"paper":{"title":"Metrology in a two-electron atom: The ionization energy of metastable triplet helium ($\\mathbf{2\\,^3S}_\\mathbf{1}$)","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":[],"primary_cat":"physics.atom-ph","authors_text":"Fr\\'ed\\'eric Merkt, Gloria Clausen, Hansj\\\"urg Schmutz, Josef A. Agner, Kai Gamlin","submitted_at":"2025-01-06T12:49:34Z","abstract_excerpt":"Helium (He) is the ideal atom to perform tests of ab-initio calculations in two-electron systems that consider all known effects, including quantum-electrodynamics and nuclear-size contributions. Recent state-of-the-art calculations and measurements of energy intervals involving the He $2\\;^3S_1$ metastable state reveal discrepancies at the level of $7\\,\\sigma$ that require clarification both from the experimental and theoretical sides. We report on a new determination, with unprecedented accuracy, of the ionization energy $E_\\mathrm{I}\\,(2\\;^3S_1)$ of the $(1s)(2s)\\;^3S_1$ metastable state of"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2501.02983","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/2501.02983/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"}