{"paper":{"title":"Near-critical magnetic fields in Kepler red giants","license":"http://creativecommons.org/licenses/by/4.0/","headline":"Near-critical magnetic fields of 100 to 700 kG confined below the hydrogen-burning shell explain irregular g-mode periods in eight Kepler red giants.","cross_cats":[],"primary_cat":"astro-ph.SR","authors_text":"F. Ligni\\`eres, G. Li, J. Ballot, M. Villate, S. Deheuvels","submitted_at":"2026-04-10T20:55:01Z","abstract_excerpt":"The recent seismic detection of magnetic fields in red giants cores has given the opportunity to characterize these fields, potentially giving information about their origin and their role in the internal transport of angular momentum. We detect strong deviations from the regular pattern of g-mode periods in eight Kepler red giants showing $l=1$ doublets. In three of these stars, the modes show partial suppression. We investigate the magnetic origin of these features and determine the characteristics of the core fields that can produce such signatures. We need to invoke strong, near-critical f"},"claims":{"count":4,"items":[{"kind":"strongest_claim","text":"We show that very good fits to all the observations can be obtained by identifying the two components as m=0 and m=1. These solutions correspond to fields with intensities ranging from 100 to 700 kG that are confined well below the H-burning shell. Our best-fit models for the eight stars have low masses (1.1-1.2 M⊙) and the maximal size of their convective core during the main sequence approximately corresponds to the radial extent of the measured magnetic fields. The detected fields could thus have been generated by dynamo action in the main-sequence convective core.","source":"verdict.strongest_claim","status":"machine_extracted","claim_id":"C1","attestation":"unclaimed"},{"kind":"weakest_assumption","text":"The observed deviations from regular g-mode periods and the partial suppressions are produced by magnetic fields rather than other mechanisms, and the adapted non-perturbative formalism remains accurate for near-critical field strengths; the choice to identify the doublet components as m=0 and m=1 rather than m=±1 is also required for the fits.","source":"verdict.weakest_assumption","status":"machine_extracted","claim_id":"C2","attestation":"unclaimed"},{"kind":"one_line_summary","text":"Near-critical magnetic fields of 100-700 kG confined below the H-burning shell are inferred in eight Kepler red giants via non-perturbative modeling of mixed-mode frequencies, identifying components as m=0 and m=1 rather than m=±1.","source":"verdict.one_line_summary","status":"machine_extracted","claim_id":"C3","attestation":"unclaimed"},{"kind":"headline","text":"Near-critical magnetic fields of 100 to 700 kG confined below the hydrogen-burning shell explain irregular g-mode periods in eight Kepler red giants.","source":"verdict.pith_extraction.headline","status":"machine_extracted","claim_id":"C4","attestation":"unclaimed"}],"snapshot_sha256":"6dc4492fec33072e58b2e187f341cb5d91d460c5d92118a2a173ad1615bb9651"},"source":{"id":"2604.09901","kind":"arxiv","version":1},"verdict":{"id":"d076e7a0-b2cc-40c2-9e0b-8c2054b99134","model_set":{"reader":"grok-4.3"},"created_at":"2026-05-10T16:40:21.411169Z","strongest_claim":"We show that very good fits to all the observations can be obtained by identifying the two components as m=0 and m=1. These solutions correspond to fields with intensities ranging from 100 to 700 kG that are confined well below the H-burning shell. Our best-fit models for the eight stars have low masses (1.1-1.2 M⊙) and the maximal size of their convective core during the main sequence approximately corresponds to the radial extent of the measured magnetic fields. The detected fields could thus have been generated by dynamo action in the main-sequence convective core.","one_line_summary":"Near-critical magnetic fields of 100-700 kG confined below the H-burning shell are inferred in eight Kepler red giants via non-perturbative modeling of mixed-mode frequencies, identifying components as m=0 and m=1 rather than m=±1.","pipeline_version":"pith-pipeline@v0.9.0","weakest_assumption":"The observed deviations from regular g-mode periods and the partial suppressions are produced by magnetic fields rather than other mechanisms, and the adapted non-perturbative formalism remains accurate for near-critical field strengths; the choice to identify the doublet components as m=0 and m=1 rather than m=±1 is also required for the fits.","pith_extraction_headline":"Near-critical magnetic fields of 100 to 700 kG confined below the hydrogen-burning shell explain irregular g-mode periods in eight Kepler red giants."},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2604.09901/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"references":{"count":4,"sample":[{"doi":"","year":null,"title":"\" * write output.state after.block = add.period write newline","work_id":"f2991c5f-316b-4fdb-ae58-785aab5ea328","ref_index":1,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":null,"title":"write newline","work_id":"71346d7f-b64e-444a-bd13-0c3c1e16fcea","ref_index":2,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":null,"title":", \" * write output.state after.block = add.period write newline","work_id":"e8f9ea09-3c4c-4fbe-9e70-c403ce2d307a","ref_index":3,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":null,"title":"write newline","work_id":"3a16abe4-80fe-40c6-84c6-3c19dc54c159","ref_index":4,"cited_arxiv_id":"","is_internal_anchor":false}],"resolved_work":4,"snapshot_sha256":"6f0e9ddc74cd9a5a54087ba016c43965293c18997e5b14cd3abb2281350ba6d7","internal_anchors":0},"formal_canon":{"evidence_count":2,"snapshot_sha256":"794ebb1e23341677fd12a9c72101efc80107957618a0eec62c85bf6d0d296d16"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}