{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"9831427d0db0245a93c93049747d5b94d788f1f9ce4b1ab0aef43aeebd5ae445","created":"2026-10-03T07:17:55Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"85d476b9236804623b3bbe6328a99dfdc05647d679d63074e7ac083a07f311b7","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"value","assisted_by":[],"external_id":"astro.r-process-sites.kilonova-lanthanides","kind":"well-posed","literature_status":"partially-resolved","n":"1","parents":[],"plain":"The glow of the 2017 neutron-star merger depends on how much of the rare-earth elements (lanthanides) it made, which is uncertain because their atomic data are poor.","posed_since":"2017","precise":"For AT2017gfo, the kilonova of GW170817, determine the ejecta mass, lanthanide mass fraction $X_{\\mathrm{lan}}$ and the presence of specific elements (strontium identified; tellurium, lanthanum, cerium candidates) using radiative transfer with complete atomic line data and non-LTE physics. Answer: $X_{\\mathrm{lan}}$ and ejecta mass with uncertainties, and whether the pattern matches the solar r-process pattern including the third peak.","problem_ref":null,"references":"","settled_by":"Non-LTE radiative-transfer fits with laboratory-calibrated lanthanide atomic data applied to the full spectral series of AT2017gfo and later kilonovae.","status_note":"2019: strontium was identified in AT2017gfo; the full abundance pattern remains model dependent.","title":"How much lanthanide mass did the GW170817 kilonova eject?","topic_ref":"629fb53d8771f28ff08120cbd19ad49c2c6fdc9fd60798b0f0a9704b24fc3033"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"7af241df01f5ec50e68c00c400462261edf5a4b32b54cd6c8b34e02526e9c844","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"87fc391ffc902481b4ef0de4f5bbf3f52ecbdfa674eae5db893af1b1310541dd","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"gadPI-joRRVaCymuj4f7iaxZQMb3WZPCwIfsxeISGQQt9kA-TJyVD5bC4cwIhHYpfpIEOoRyG9eRFyeBihBaBw"},"schema":"pubphys.envelope/1"},"record_hash":"7af241df01f5ec50e68c00c400462261edf5a4b32b54cd6c8b34e02526e9c844","leaf_index":594}