Paper CLII of the One-Octonion Brane-Bulk Series Anomalous Nickel Isotope Enrichment in Presolar Supernova SiC Grains:

Systematic analysis of the Presolar Grain Database (Stephan et al. 2024; v. 2025-03-10) for 705 X-type (supernova) and 16,899 mainstream (AGB) SiC grains reveals a large unexplained Ni-isotope excess in the X-type population. X-type mean δ(61Ni/58Ni) = +534 ± 819 versus +134 ± 161 in mainstream grains (Mann–Whitney p = 4.5 × 10−3; Welch t = 3.42, p ∼10−3). The most anomalous grain (M08-249-8) shows δ(61Ni) = +4607, 5.8× the ceiling of the best-fit supernova nucleosynthesis model (Hoppe et al. 2018). δ(61Ni)/δ(60Ni) = 13.4 in M08-249-8, physically impossible by sequential neutron capture. δ(61Ni) is uncorrelated with δ(54Fe) (r = 0.25, p = 0.08). We identify the residual mechanism as forced β-decay: γ + ACo →ANi + e−+ ¯νe driven by the ambient photon bath in transient magnetar-strength fields (B ≳1010 T) during core collapse. The signature transition is 59Co →59Ni, which is Q-forbidden as a spontaneous β−- decay (Q = −1.07 MeV, since 59Ni is heavier than 59Co), but becomes kinematically allowed when the electron cyclotron energy ℏωc = eBℏ/me exceeds 1.07 MeV — satisfied for B ≥1010 T. The other three isobaric pairs 60,61,62Co →60,61,62Ni are spontaneously β−-unstable but slow (T1/2 of 5.27 yr, 1.65 h, 1.50 min); forced β-decay accelerates them during the transient phase before grain condensation. The channel is mediated by the 6 square faces of the G2 permutohedron, which correspond to H−-sector long-root generators carrying the ∆Z = ±1, ∆A = 0 weak charge-changing vertex (Paper CXXXVIII). Three predictions follow; zero free parameters. Part of the One-Octonion Brane-Bulk Framework series. Anchor DOI: 10.5281/zenodo.19120873. Community: one-octonion-brane-bulk. Author: Bharathi Dasan Jagadeesan, M.D., University of Minnesota. ORCID: 0000-0002-1143-941X.