{"paper":{"title":"Revisiting the ultraviolet spectroscopy of the eta Tel edge-on debris disk","license":"http://creativecommons.org/licenses/by/4.0/","headline":"A -1 km/s absorption feature toward eta Tel is likely circumstellar gas with low C/O ratio.","cross_cats":["astro-ph.SR"],"primary_cat":"astro-ph.EP","authors_text":"Aki Roberge, Alexis Brandeker, Allison Youngblood, Alycia Weinberger, Barry Welsh, Meredith A. MacGregor, Sebastian Perez","submitted_at":"2026-05-12T18:11:09Z","abstract_excerpt":"We revisit the ultraviolet absorption spectroscopy of the edge-on debris disk surrounding the A0V star $\\eta$ Telescopii. Previous work found absorption components at four velocities ($\\sim$ -23, -18, -10, -1 km s$^{-1}$), with the most blueshifted component (-23 km s$^{-1}$) interpreted as a likely disk wind. However, optical spectroscopy of $\\eta$ Tel and other nearby stars in projection demonstrate that the -23 km s$^{-1}$ component is likely interstellar in origin. We find that there are three interstellar components toward this sight line (-23, -18, -10 km s$^{-1}$), but that the fourth c"},"claims":{"count":4,"items":[{"kind":"strongest_claim","text":"the fourth component near -1 km s^{-1}, which was only detected in O I, is inconsistent with an interstellar origin and could be circumstellar. We place a 3-σ upper limit on the C/O ratio of the -1 km s^{-1} gas (log C/O < -2.1)","source":"verdict.strongest_claim","status":"machine_extracted","claim_id":"C1","attestation":"unclaimed"},{"kind":"weakest_assumption","text":"That the -1 km/s component is not interstellar, based on velocity matching to optical spectroscopy of eta Tel and projected nearby stars.","source":"verdict.weakest_assumption","status":"machine_extracted","claim_id":"C2","attestation":"unclaimed"},{"kind":"one_line_summary","text":"The -1 km/s absorption toward eta Tel is circumstellar with log C/O < -2.1, matching solar system comet abundances but not carbon-rich disks around hotter stars.","source":"verdict.one_line_summary","status":"machine_extracted","claim_id":"C3","attestation":"unclaimed"},{"kind":"headline","text":"A -1 km/s absorption feature toward eta Tel is likely circumstellar gas with low C/O ratio.","source":"verdict.pith_extraction.headline","status":"machine_extracted","claim_id":"C4","attestation":"unclaimed"}],"snapshot_sha256":"3d8e72830bca713e4dddb3e6b1b6fa3403531c69a59e14d657ac9747f731d2c6"},"source":{"id":"2605.12627","kind":"arxiv","version":1},"verdict":{"id":"268c8f4a-fc9e-4951-8408-b4993faed632","model_set":{"reader":"grok-4.3"},"created_at":"2026-05-14T20:13:48.772502Z","strongest_claim":"the fourth component near -1 km s^{-1}, which was only detected in O I, is inconsistent with an interstellar origin and could be circumstellar. We place a 3-σ upper limit on the C/O ratio of the -1 km s^{-1} gas (log C/O < -2.1)","one_line_summary":"The -1 km/s absorption toward eta Tel is circumstellar with log C/O < -2.1, matching solar system comet abundances but not carbon-rich disks around hotter stars.","pipeline_version":"pith-pipeline@v0.9.0","weakest_assumption":"That the -1 km/s component is not interstellar, based on velocity matching to optical spectroscopy of eta Tel and projected nearby stars.","pith_extraction_headline":"A -1 km/s absorption feature toward eta Tel is likely circumstellar gas with low C/O ratio."},"references":{"count":48,"sample":[{"doi":"10.1016/s0012-821x(00)00359-9","year":2001,"title":"Earth and Planetary Science Letters , year = 2001, month = feb, volume =","work_id":"2210ff1f-cc40-46a3-9617-ef74fa18c7f3","ref_index":1,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":1993,"title":"E., & Paresce , F","work_id":"076e8bf5-08d5-4938-a172-cea3b56b34ea","ref_index":2,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":1990,"title":"Beust , H., Vidal-Madjar , A., Ferlet , R., & Lagrange-Henri , A. M. 1990, title The Beta Pictoris circumstellar disk. X - Numerical simulations of infalling evaporating bodies , , 236, 202. http://ad","work_id":"b47b99e0-77e4-486d-bce9-b0670d01f27e","ref_index":3,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"10.1051/0004-6361/201628395","year":2016,"title":"2016, title Herschel detects oxygen in the Pictoris debris disk , , 591, A27, 10.1051/0004-6361/201628395","work_id":"8129d6bd-c1a9-4686-b12b-a417a77c1657","ref_index":4,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"10.3847/1538-4357/ad74f4","year":2024,"title":"and Worthen, Kadin and Li, Alexis and Sefilian, Antranik A","work_id":"30d817dd-f5b6-445b-94bc-6db81807c6de","ref_index":5,"cited_arxiv_id":"","is_internal_anchor":false}],"resolved_work":48,"snapshot_sha256":"7b0a6f2b09ed00b212b6257e82827694aaa91f1932448fc80f74ad2550814fb5","internal_anchors":0},"formal_canon":{"evidence_count":2,"snapshot_sha256":"97f981787c47f405126a8097857087e8d33f093d1c751208c0d87471fb2fd14a"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}