{"paper":{"title":"Robust Constraint on a Drifting Proton-to-Electron Mass Ratio at z=0.89 from Methanol Observation at Three Radio Telescopes","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.GA"],"primary_cat":"astro-ph.CO","authors_text":"4), Christian Henkel (3, Germany (4) King Abdulaziz University, Hendrick L. Bethlem (1), Julija Bagdonaite (1), Karl M. Menten (3) ((1) VU University Amsterdam, Mario Dapr\\`a (1), Netherlands (2) Onsala Space Observatory, Paul Jansen (1), Saudi Arabia), S\\'ebastien Muller (2), Sweden (3) Max-Planck-Institut f\\\"ur Radioastonomie, Wim Ubachs (1)","submitted_at":"2013-11-14T10:19:07Z","abstract_excerpt":"A limit on a possible cosmological variation of the proton-to-electron mass ratio $\\mu$ is derived from methanol (CH$_3$OH) absorption lines in the benchmark PKS1830$-$211 lensing galaxy at redshift $z = 0.89$ observed with the Effelsberg 100-m radio telescope, the Institute de Radio Astronomie Millim\\'{e}trique 30-m telescope, and the Atacama Large Millimeter/submillimeter Array. Ten different absorption lines of CH$_3$OH covering a wide range of sensitivity coefficients $K_{\\mu}$ are used to derive a purely statistical 1-$\\sigma$ constraint of $\\Delta\\mu/\\mu = (1.5 \\pm 1.5) \\times 10^{-7}$ f"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1311.3438","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"}