{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"28b89d9f1aa9852422a63efac7d0077dff85b758f15383df70f91908600056b4","created":"2026-10-03T07:18:08Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"b3b7bc4205945b8e05b4c0a58a9f9d0d8b4f84315efc2a638707f7f40d04dd0e","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"value","assisted_by":[],"external_id":"nuc.r-process-nuclear.n126-masses-halflives","kind":"well-posed","literature_status":"open","n":"1","parents":[],"plain":"The third abundance peak, near platinum and gold, forms where neutron-rich nuclei with 126 neutrons pause before decaying further. Almost none of these nuclei have been measured.","posed_since":"","precise":"Measure atomic masses to 10 keV and beta-decay half-lives to 10 percent for $N = 126$ isotones with $Z = 64\\text{ to }72$ and neighbors with $N = 124\\text{ to }130$, and test mass models (typical rms deviation about 0.5 MeV away from stability) and half-life predictions. Answer: measured values and the resulting shift in the predicted position and width of the $A\\text{ about }195$ abundance peak.","problem_ref":null,"references":"","settled_by":"Multinucleon-transfer production at KISS (RIKEN) and the $N = 126$ Factory (Argonne), and fragmentation at FRIB, with Penning-trap or multi-reflection mass spectrometry and decay spectroscopy.","status_note":"","title":"Masses and half-lives of $N = 126$ waiting-point nuclei","topic_ref":"008542e5fb6a342c0c764df9c1f7e628886ae3efa8048a1b79e833430d025799"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"ba19f73516f24aa29b57c5e39d4a6bfcb1d59d04b8934bb0b17be0f2dd19173d","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"b2e38e25d0204cb108411902bd4133ff77f5a8b66e1c4580dc9a75068253a7e4","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"gkNpqxCu--LA-per3ijL_Cba4HtGa0uXAz7JR4P2mLzktaiBIRYlA5P5iSyGDpEpZEUD6dh3mnHgSbxNPFGZBg"},"schema":"pubphys.envelope/1"},"record_hash":"ba19f73516f24aa29b57c5e39d4a6bfcb1d59d04b8934bb0b17be0f2dd19173d","leaf_index":1808}