{"paper":{"title":"Optical constraints on the coldest metal-poor population","license":"http://creativecommons.org/publicdomain/zero/1.0/","headline":"","cross_cats":["astro-ph.GA"],"primary_cat":"astro-ph.SR","authors_text":"Bartosz Gauza, Carlos Quezada, Eduardo L. Mart\\'in, Henri M. J. Boffin, Jerry Jun-Yan Zhang, Mar\\'ia Rosa Zapatero Osorio, Nafise Sedighi, Nicolas Lodieu, Rafael Rebolo, Tariq Shahbaz, Valentin D. Ivanov, Victor J. S. B\\'ejar, Yakiv V. Pavlenko","submitted_at":"2024-12-05T18:08:01Z","abstract_excerpt":"The coldest metal-poor population made of T and Y dwarfs are archaeological tracers of our Galaxy because they are very old and have kept the pristine material. The optical properties of these objects are important to characterise their atmospheric properties. We aim at characterising further the optical properties of ultracool metal-poor population with deep far-red optical images and parallax determinations.\n  With a two-year baseline, we solved trigonometric parallaxes of the five metal-poor T dwarf candidates using Calar-Alto 3.5-m telescope. We obtained $z'$-band photometry for the other "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2412.04393","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":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2412.04393/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"}