{"paper":{"title":"A stellar bar hidden in an extreme gas-rich disk galaxy at z=4.055","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"A stellar bar has formed in a gas-rich disk galaxy at z=4.055, showing bars can develop rapidly despite high gas content.","cross_cats":["astro-ph.CO"],"primary_cat":"astro-ph.GA","authors_text":"Alejandro Crespo G\\'omez, Arjan Bik, Axel Weiss, Cheng-Lin Liao, Emanuele Daddi, Fabian Walter, Georgios E. Magdis, Hannah \\\"Ubler, Jacqueline A. Hodge, Joss Bland-Hawthorn, Leindert A. Boogaard, Luca Costantin, Luis Colina, Mahmoud Hamed, Oscar Agertz, Pablo G. P\\'erez-Gonz\\'alez, Thor Tepper-Garc\\'ia","submitted_at":"2026-05-14T18:00:02Z","abstract_excerpt":"The classical picture for the formation of stellar bars -- key dynamical drivers of the evolution of galaxies -- is through secular evolution of instability in gas poor, stellar-dominated disks. The detection with the James Webb Space Telescope (JWST) of stellar bars and spiral arms in galaxies at early cosmic times has thus challenged LambdaCDM-based expectations, which recent studies reconcile by suggesting that these galaxies are baryon-dominated and have already consumed most of their gas. Yet, a paradox arises, as early galaxies are expected to be increasingly rich in gas, which is genera"},"claims":{"count":4,"items":[{"kind":"strongest_claim","text":"This discovery demonstrates that gas-rich disks do support rapid stellar bar formation in the early Universe, motivating a new theoretical perspective on bar formation in gas-rich systems, and providing a potential new mechanism for very early galaxy assembly and quenching.","source":"verdict.strongest_claim","status":"machine_extracted","claim_id":"C1","attestation":"unclaimed"},{"kind":"weakest_assumption","text":"The identification of the observed central structure as a stellar bar and the accuracy of the baryon (70+/-30%) and gas (75+/-25%) mass fractions derived from simultaneous JWST observations of stars, gas, and dust (abstract, paragraphs describing the detection and mass estimates).","source":"verdict.weakest_assumption","status":"machine_extracted","claim_id":"C2","attestation":"unclaimed"},{"kind":"one_line_summary","text":"A stellar bar is detected in the gas-rich galaxy GN20 at z=4.055, showing that gas-rich disks can support rapid stellar bar formation in the early universe.","source":"verdict.one_line_summary","status":"machine_extracted","claim_id":"C3","attestation":"unclaimed"},{"kind":"headline","text":"A stellar bar has formed in a gas-rich disk galaxy at z=4.055, showing bars can develop rapidly despite high gas content.","source":"verdict.pith_extraction.headline","status":"machine_extracted","claim_id":"C4","attestation":"unclaimed"}],"snapshot_sha256":"8fe7b87a330d792dc1991dcf03857ca9211cbda106abefd99eb1c50ee4718178"},"source":{"id":"2605.15273","kind":"arxiv","version":1},"verdict":{"id":"8c4656ca-cc5e-4d2c-8631-b02f27730281","model_set":{"reader":"grok-4.3"},"created_at":"2026-05-19T15:51:01.271994Z","strongest_claim":"This discovery demonstrates that gas-rich disks do support rapid stellar bar formation in the early Universe, motivating a new theoretical perspective on bar formation in gas-rich systems, and providing a potential new mechanism for very early galaxy assembly and quenching.","one_line_summary":"A stellar bar is detected in the gas-rich galaxy GN20 at z=4.055, showing that gas-rich disks can support rapid stellar bar formation in the early universe.","pipeline_version":"pith-pipeline@v0.9.0","weakest_assumption":"The identification of the observed central structure as a stellar bar and the accuracy of the baryon (70+/-30%) and gas (75+/-25%) mass fractions derived from simultaneous JWST observations of stars, gas, and dust (abstract, paragraphs describing the detection and mass estimates).","pith_extraction_headline":"A stellar bar has formed in a gas-rich disk galaxy at z=4.055, showing bars can develop rapidly despite high gas content."},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2605.15273/integrity.json","findings":[],"available":true,"detectors_run":[{"name":"doi_compliance","ran_at":"2026-05-19T16:05:35.012304Z","status":"completed","version":"1.0.0","findings_count":0},{"name":"doi_title_agreement","ran_at":"2026-05-19T16:01:18.204132Z","status":"completed","version":"1.0.0","findings_count":0},{"name":"claim_evidence","ran_at":"2026-05-19T14:41:54.261467Z","status":"completed","version":"1.0.0","findings_count":0},{"name":"ai_meta_artifact","ran_at":"2026-05-19T13:33:22.802546Z","status":"skipped","version":"1.0.0","findings_count":0}],"snapshot_sha256":"e3a0b257b5b35f9a49bbe1af2fbad957f1ce2223904a2d811eaa6729d65ab1b2"},"references":{"count":100,"sample":[{"doi":"","year":2000,"title":"2000, A&A, 361, 841","work_id":"d067cfc8-ca10-4fd4-9605-6e5d98d18a4b","ref_index":1,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"10.1093/mnras/staf048","year":2025,"title":"Amvrosiadis, A., Lange, S., Nightingale, J. 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