{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"fbba5e6f7680409f4e21a80c4cae255d8268d286173ac90f7df44f23fef38c77","created":"2026-10-03T07:17:55Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"7f4bf378c4946543f02f265f93423f31120b578d84c57065daa1dd67e19cf081","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"classification","assisted_by":[],"external_id":"astro.sn-ia-progenitors.explosion-mass","kind":"well-posed","literature_status":"contested","n":"1","parents":[],"plain":"The exploding white dwarf may be close to the maximum mass a white dwarf can have (about 1.4 Suns), or lighter, with a helium layer on its surface detonating first and setting off the core. Each picture predicts different elements in the debris.","posed_since":"","precise":"For normal SNe Ia, decide whether the exploding white dwarf is near $M_{\\mathrm{Ch}} = 1.38\\,M_{\\mathrm{sun}}$ with a deflagration-to-detonation transition, or at $0.9\\ \\text{to}\\ 1.1\\,M_{\\mathrm{sun}}$ exploding by a helium-shell detonation that triggers a carbon-oxygen core detonation (double detonation), and give the fraction of each. Discriminating observables include $\\mathrm{Mn}/\\mathrm{Fe}$ and stable $\\mathrm{Ni}/\\mathrm{Fe}$ in ejecta and nebular spectra, the stratification of Ca and other intermediate-mass elements in young remnants, and early-time spectra.","problem_ref":null,"references":"","settled_by":"Nebular-phase stable Ni and Mn yields and remnant element stratification for a statistical sample, compared with 3D explosion models of both classes.","status_note":"In 2025 a double calcium shell in the young Large Magellanic Cloud remnant SNR 0509-67.5 was reported as the predicted signature of a double detonation (Das et al., Nature Astronomy, 2025); whether this is the common route remains open.","title":"Chandrasekhar-mass or sub-Chandrasekhar-mass white dwarfs in normal Type Ia supernovae","topic_ref":"725883c9f1fa87da8eacd23b3ad9211426658a588d96f1c1bbacc3e7a502c79e"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"61381d3ab3511aef413d0e7d712b35bed811bfb02604b7f621e83210591c1465","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"7f24a9cf107d9ce6abe4a5bdc3cd735a5b433565feccb1f1da2aab72057f4d44","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"iNcpi_C6nkc_88fdhnL-YGKcLpb-9sxkWOFCPO5--TULc6ykIXLv45B0-VJ4NIylw2DFZ7X81wiez8aWqn8IAw"},"schema":"pubphys.envelope/1"},"record_hash":"61381d3ab3511aef413d0e7d712b35bed811bfb02604b7f621e83210591c1465","leaf_index":607}