{"paper":{"title":"Excavating The Ruins: an Ancient $z=2.675$ Galaxy Which Formed in the First 500 Myr","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.GA","authors_text":"Adam Muzzin, Adit Edward, Allison Noble, Ben Forrest, Danilo Marchesini, Gillian Wilson, Han Lei, Ian McConachie, Jacqueline Antwi-Danso, M. C. Cooper, M. E. Wisz, Michael V. Maseda, Percy Gomez, Stephanie M. Urbano Stawinski, Tracy Webb, Wenjun Chang, Zach J. Lewis","submitted_at":"2025-08-07T18:10:38Z","abstract_excerpt":"We present the analysis of an ancient galaxy at $z=2.675$ which we dub ``Eridu.'' Simultaneously modeling the JWST/NIRSpec G140M and G235M spectra from the SMILES program and $0.4-25\\ \\mu\\mathrm{m}$ HST, JWST/NIRCam, and JWST/MIRI photometry from the the JADES+SMILES photometric catalogs shows that Eridu is massive and quiescent with stellar mass $\\log(M_*/\\mathrm{M_\\odot})=10.96^{+0.01}_{-0.01}$ and average star formation rate $<1\\ \\mathrm{M_\\odot\\ yr^{-1}}$ over the last 100 Myr. Star formation histories inferred from various models produce disconcertingly early and fast formation within $\\s"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2508.05752","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/2508.05752/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"}