{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"ac0b614a434722c8fab7c8221d00214802e871cdab4eb945de48d024bbbb0197","created":"2026-10-03T07:17:55Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"11262e03b69819bd751de4cb6815055ec28f78249236fef3bb50bc2c0e9ca051","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":"1","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 $\\sim 1\\,\\text{percent}$), 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 $T \\sim 2e6\\,\\mathrm{K}$ or other physics are needed. Answer: $Z/X$ with uncertainty consistent with helioseismology and the CNO solar neutrino flux.","problem_ref":null,"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":"198e5d8c650c549166ecfcbee7e1125fa6cc28a6930904820f971b95ad0953ee"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"483b027cad46309772c129b970ba56a9602a6857883e6d1100f1d5ba933352c7","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"07bac6bceffb7d11708eb1982326f91c1c21cebd44afe5ad9a02377b8fbda1a8","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"2FsNhmaVjJX5PtWEfFNQ2S-atrGlPCM2PxeTvk96HbFEh8s8_fCfy9iDz8Gm7UDaZRiu58a8VQhX2zgOyVPSDw"},"schema":"pubphys.envelope/1"},"record_hash":"483b027cad46309772c129b970ba56a9602a6857883e6d1100f1d5ba933352c7","leaf_index":617}