{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"af6b83b7fc972099be9a16fff42b1c2e5b6b7d292716fc119b2b686adad8c3c8","created":"2026-10-15T23:43:22Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["483b027cad46309772c129b970ba56a9602a6857883e6d1100f1d5ba933352c7","ce59fb6cd812fc05906d0c60a71c75ea22bc686bcf38e7c3ef7010834d98ee7b"],"salt":"330e1b06771d43bd94446d4d5144da2066293a7dfcc708c4a805635c25e4a851","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"value","assisted_by":[],"external_id":"astro.solar-interior-cycle.abundance-problem","kind":"well-posed","literature_status":"contested","n":"2","parents":[],"plain":"Measurements of the Sun's surface composition give less carbon, oxygen and other heavy elements than the Sun's internal sound waves imply.","posed_since":"2005","precise":"Standard solar models using 3D non-LTE photospheric abundances (Asplund et al. 2009 and 2021, $Z/X \\sim 0.018$) disagree with the helioseismic sound speed below the convection zone (deviations $\\sim 1\\%$), the convection-zone base $R_{\\mathrm{cz}} = 0.713\\,R_{\\mathrm{sun}}$ and surface helium $Y_{s} \\sim 0.248$, while higher-metallicity analyses (Magg et al. 2022, $Z/X = 0.0225$) restore much of the agreement. Determine the correct metal content and whether opacity revisions near $T \\sim 2 \\times 10^{6}\\,\\mathrm{K}$ or other physics are needed. Answer: $Z/X$ with uncertainty consistent with helioseismology and the CNO solar neutrino flux.","problem_ref":"483b027cad46309772c129b970ba56a9602a6857883e6d1100f1d5ba933352c7","references":"","settled_by":"A precise CNO neutrino flux measurement (fixing core C+N) together with laboratory opacity measurements at solar interior conditions.","status_note":"Borexino CNO neutrino fluxes (2020-2022) mildly favor the higher-metallicity composition; helioseismic opacity inversions suggest opacities above current tables near the convection-zone base.","title":"Resolve the conflict between solar abundances and helioseismology","topic_ref":null},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"02a856e0390be68acb6d5c97663e4d5b8e6259c099df4a6dd45e6413ddc25290","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"289dcb4e3128862ec0e766218015240235c2a8aa940d3cd0769a3a623dd1b518","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"yxUDrlCHnHW_p-vD5miTY3sQjPv-QjTzhfPdt2jTK7HBDGzqH9CX1_UtGgAgI5jJjDRn98NOB9T7VzaW6teNCQ"},"schema":"pubphys.envelope/1"},"record_hash":"02a856e0390be68acb6d5c97663e4d5b8e6259c099df4a6dd45e6413ddc25290","leaf_index":2432}