{"paper":{"title":"The CO A-X System for Constraining Cosmological Drift of the Proton-Electron Mass Ratio","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"physics.atom-ph","authors_text":"D. Joyeux, E. J. Salumbides, J. Bagdonaite, L. Nahon, M. L. Niu, N. de Oliveira, W. Ubachs","submitted_at":"2012-08-23T10:44:39Z","abstract_excerpt":"The $\\textrm{A}^1\\Pi-\\textrm{X}^1\\Sigma^+$ band system of carbon monoxide, which has been detected in six highly redshifted galaxies ($z=1.6-2.7$), is identified as a novel probe method to search for possible variations of the proton-electron mass ratio ($\\mu$) on cosmological time scales. Laboratory wavelengths of the spectral lines of the A-X ($v$,0) bands for $v=0-9$ have been determined at an accuracy of $\\Delta\\lambda/\\lambda=1.5 \\times 10^{-7}$ through VUV Fourier-transform absorption spectroscopy, providing a comprehensive and accurate zero-redshift data set. For the (0,0) and (1,0) ban"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1208.4715","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":""},"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"}