{"paper":{"title":"omega Centauri - a former nucleus of a dissolved dwarf galaxy? New evidence from Stroemgren photometry","license":"","headline":"","cross_cats":[],"primary_cat":"astro-ph","authors_text":"(2) Univ. de Concepcion, Chile, Chile), Michael Hilker (1), Santiago, Tom Richtler (2) ((1) P. Univ. Catolica","submitted_at":"2000-08-30T21:02:17Z","abstract_excerpt":"CCD vby Stroemgren photometry of a statistically complete sample of red giants and stars in the main sequence turn-off region in omega Centauri has been used to analyse the apparently complex star formation history of this cluster. From the location of stars in the (b-y),m_1 diagram metallicities have been determined. These have been used to estimate ages of different sub-populations in the color-magnitude diagram. The metal-poor population around -1.7 dex is the oldest population found. More metal-rich stars between [Fe/H]=-1.5 and -1.0 dex tend to be 1-3 Gyr younger. These stars are more con"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"astro-ph/0008500","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/astro-ph/0008500/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"}