{"paper":{"title":"Panchromatic View of the Frigid Jovian Exoplanet COCONUTS-2 b","license":"http://creativecommons.org/licenses/by/4.0/","headline":"Panchromatic 1-15 micron observations with ATMO2020++ models constrain COCONUTS-2 b to 496 K, 1.03 Jupiter radii, and 7.3 Jupiter masses.","cross_cats":[],"primary_cat":"astro-ph.EP","authors_text":"Alice Radcliffe, Allan Denis, Arthur Vigan, Benjamin Charnay, Caroline V. Morley, Elena Manjavacas, Elisabeth C. Matthews, Gabriel-Dominique Marleau, Ga\\\"el Chauvin, Helena K\\\"uhnle, Jacqueline K. Faherty, James J. Mang, Jessica Copeland, Kevin Hoy, Ma\\\"el Voyer, Mark W. Phillips, Mathilde M\\^alin, Matthieu Ravet, Micka\\\"el Bonnefoy, Pascal Tremblin, Paulina Palma-Bifani, Paul Molli\\`ere, Rocio Kiman, Sam de Regt, Simon Petrus, Thomas K. Henning, Zhoujian Zhang","submitted_at":"2026-04-08T15:05:17Z","abstract_excerpt":"We use a high signal-to-noise MIRI-LRS spectrum (5.45 - 11 $\\mu$m, R$_\\lambda$ $\\sim100$) of COCONUTS-2~b revealing prominent molecular features of H$_2$O, CH$_4$ and NH$_3$. This dataset is combined with spectra from Gemini/FLAMINGOS-2 and JWST/NIRSpec (G395H), as well as photometry from WISE and Spitzer, resulting in almost continuous wavelength coverage from 1 to 15 $\\mu$m. We analyze the data using five grids of self-consistent atmospheric models, spanning a wide range of T$_\\text{eff}$, log(g), and [M/H]. We also investigate the use of Gaussian Processes to account for correlated noise ei"},"claims":{"count":4,"items":[{"kind":"strongest_claim","text":"ATMO2020++ models yield constraints consistent with previous studies: T_eff =496^{+5}_{-3} K, log(g) =4.30^{+0.04}_{-0.02} dex, [M/H] =-0.02^{+0.03}_{-0.02} dex, R =1.03^{+0.01}_{-0.02} R_jup, and mass M =7.3±0.3 M_jup from cooling models given the system age.","source":"verdict.strongest_claim","status":"machine_extracted","claim_id":"C1","attestation":"unclaimed"},{"kind":"weakest_assumption","text":"That the ATMO2020++ (and other) self-consistent atmospheric model grids accurately capture the physics and chemistry of this cold atmosphere, despite systematically underpredicting flux in the Y- and N-bands.","source":"verdict.weakest_assumption","status":"machine_extracted","claim_id":"C2","attestation":"unclaimed"},{"kind":"one_line_summary","text":"Panchromatic 1-15 micron observations of COCONUTS-2 b yield Teff=496 K, log g=4.3, near-solar metallicity, radius 1.03 Rjup, luminosity log(L/Lsun)=-6.166, and mass 7.3 Mjup from evolutionary models.","source":"verdict.one_line_summary","status":"machine_extracted","claim_id":"C3","attestation":"unclaimed"},{"kind":"headline","text":"Panchromatic 1-15 micron observations with ATMO2020++ models constrain COCONUTS-2 b to 496 K, 1.03 Jupiter radii, and 7.3 Jupiter masses.","source":"verdict.pith_extraction.headline","status":"machine_extracted","claim_id":"C4","attestation":"unclaimed"}],"snapshot_sha256":"3ffbe5bc7880d28c2087437551c5a3b8abc2d3b187703cd1178a4990c9b23445"},"source":{"id":"2604.07176","kind":"arxiv","version":1},"verdict":{"id":"2f32560b-9424-42e6-9d87-23f8351e61a6","model_set":{"reader":"grok-4.3"},"created_at":"2026-05-10T18:10:33.252878Z","strongest_claim":"ATMO2020++ models yield constraints consistent with previous studies: T_eff =496^{+5}_{-3} K, log(g) =4.30^{+0.04}_{-0.02} dex, [M/H] =-0.02^{+0.03}_{-0.02} dex, R =1.03^{+0.01}_{-0.02} R_jup, and mass M =7.3±0.3 M_jup from cooling models given the system age.","one_line_summary":"Panchromatic 1-15 micron observations of COCONUTS-2 b yield Teff=496 K, log g=4.3, near-solar metallicity, radius 1.03 Rjup, luminosity log(L/Lsun)=-6.166, and mass 7.3 Mjup from evolutionary models.","pipeline_version":"pith-pipeline@v0.9.0","weakest_assumption":"That the ATMO2020++ (and other) self-consistent atmospheric model grids accurately capture the physics and chemistry of this cold atmosphere, despite systematically underpredicting flux in the Y- and N-bands.","pith_extraction_headline":"Panchromatic 1-15 micron observations with ATMO2020++ models constrain COCONUTS-2 b to 496 K, 1.03 Jupiter radii, and 7.3 Jupiter masses."},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2604.07176/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"references":{"count":93,"sample":[{"doi":"","year":2001,"title":"Ackerman , A. S. & Marley , M. S. 2001, , 556, 872","work_id":"25f13b2a-d706-425b-91d7-ea00ec13736f","ref_index":1,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":1974,"title":"1974, IEEE Transactions on Automatic Control, 19, 716","work_id":"9e367ade-f236-4010-b6af-aec7256b3793","ref_index":2,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2025,"title":"K., Su \\'a rez , G., et al","work_id":"c0152dcf-0021-4415-bcef-20f4dd2ecd93","ref_index":3,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2013,"title":"2013, , 558, A109","work_id":"a55b9dba-2a6d-45ea-b200-065d09ab1273","ref_index":4,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2005,"title":"2005, , 434, 343","work_id":"de137a05-a47c-40df-a706-0787f8d08b83","ref_index":5,"cited_arxiv_id":"","is_internal_anchor":false}],"resolved_work":93,"snapshot_sha256":"2428d02c4ac8b3cc7241d162cf20086c7358009cba6dcdbff075109857c1aceb","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"}