{"paper":{"title":"The GALAH Survey: Temporal Chemical Enrichment of the Galactic Disk","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.GA"],"primary_cat":"astro-ph.SR","authors_text":"Andrew R. Casey, Daniel B. Zucker, Gayandhi M. De Silva, Geraint F. Lewis, Ivan Minchev, Jane Lin, Janez Kos, Jeffrey D. Simpson, Jonti Horner, Joss Bland-Hawthorn, Ken C. Freeman, Klemen \\v{C}otar, K Lind, Luca Casagrande, Martin Asplund, Maru\\v{s}a \\v{Z}erjal, Michael Hayden, Rosemary F. G. Wyse, Sanjib Sharma, Sarah L. Martell, Sven Buder, Thomas Nordlander, Toma\\v{z} Zwitter, Valentina D'Orazi, Yuan-Sen Ting","submitted_at":"2019-11-13T00:52:22Z","abstract_excerpt":"We present isochrone ages and initial bulk metallicities ($\\rm [Fe/H]_{bulk}$, by accounting for diffusion) of 163,722 stars from the GALAH Data Release 2, mainly composed of main sequence turn-off stars and subgiants ($\\rm 7000 K>T_{eff}>4000 K$ and $\\rm log g>3$ dex). The local age-metallicity relationship (AMR) is nearly flat but with significant scatter at all ages; the scatter is even higher when considering the observed surface abundances. After correcting for selection effects, the AMR appear to have intrinsic structures indicative of two star formation events, which we speculate are co"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1911.05221","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/1911.05221/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"}