{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"e42bd74133d514f713f352c414f512264ebbf14a223453a9c7fba110093975b9","created":"2026-10-15T23:43:22Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["39015d3bd3dc418826d0f250280ff88e9ffaca603aadb4336b3c7f141052a6ce","ce59fb6cd812fc05906d0c60a71c75ea22bc686bcf38e7c3ef7010834d98ee7b"],"salt":"754d5f469e61628c73b7b89859ee6b479aaf3b5ce09f350418a82790fceaffab","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"classification","assisted_by":[],"external_id":"hep.neutrino-mass.mass-ordering","kind":"well-posed","literature_status":"open","n":"2","parents":[],"plain":"We know the mass differences between the three neutrinos but not whether the odd one out is heaviest (normal ordering) or lightest (inverted ordering).","posed_since":"","precise":"Determine the sign of $\\Delta m^2_{31}$ ($\\left|\\Delta m^2_{31}\\right| \\sim 2.5 \\times 10^{-3}\\,\\mathrm{eV}^2$) at $\\ge 3\\,\\sigma$ from reactor oscillation spectra (JUNO), matter effects in long-baseline accelerator (DUNE, Hyper-K) and atmospheric data. Answer: normal or inverted.","problem_ref":"39015d3bd3dc418826d0f250280ff88e9ffaca603aadb4336b3c7f141052a6ce","references":"","settled_by":"JUNO reactor spectral data over about 6 years combined with DUNE and atmospheric experiments.","status_note":"JUNO 207-day data combined with long-baseline accelerator $\\Delta m^{2}_{31}$ constraints (arXiv:2609.37895, September 2026) favor normal ordering at one-sided $\\ge 2.1\\sigma$ for all $\\delta_{\\mathrm{CP}}$ (Bayes factor 10.18); global fits (NuFit-6.0, 2024) also lean normal; the 2025 NOvA plus T2K joint fit prefers neither.","title":"Is the neutrino mass ordering normal or inverted?","topic_ref":null},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"f03f8e5bbcb9bb0badb1893149d1e8f79d89d558e1936c13c8b87da03b23506c","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"25b509f52de08b5a311e55b198e609d211a07e3157dcd00c34ae59a59ae6957d","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"IftSknqxCOIbR82QPi3eiYeDIXwICXQkFDDvUDDP412vQHdlrcDW95Bu51r4N0gHK5de2fTuymJrDWDYnAeRCg"},"schema":"pubphys.envelope/1"},"record_hash":"f03f8e5bbcb9bb0badb1893149d1e8f79d89d558e1936c13c8b87da03b23506c","leaf_index":3378}