Paper CCXLII: *+ Hyperfine Splitting from the Dual-H- Class (Theorem 6.1 of Paper CCXLI): A Zero-Parameter Test against ATLAS arXiv:2605.16228 Research (CMRR)

The ATLAS Collaboration (arXiv:2605.16228, May 2026) reports the first observation of the Bc *+ meson with mass 6339.0 ± 1.4(stat) +1.0 -1.4(syst) MeV and hyperfine splitting Δm = 64.5 ± 1.7 MeV. The Bc = b̄c bound state is the unique heavy-flavour realization of the dual-H- meson class introduced in companion Paper CCXLI. Applying Theorem 6.1 of that paper to b̄c we predict mBc +/mBc *+ = cos(2θG2) = 2389/2413, with θG2 = arctan(2√3/49) = 4.0439° the genesis tilt derived in Paper CXXX from the baryon asymmetry δM/M ≈ 6.1×10-10. Using the PDG value mBc + = 6274.47 ± 0.27 MeV as input, this yields mBc *+ = 6337.5 MeV and Δm = 63.0 MeV, agreeing with ATLAS within 0.9σ with zero free parameters. Equivalently, Δm/mBc + = sec(2θG2) − 1 = 24/2389 ≈ 24/74. The application of Theorem 6.1 to other heavy-meson hyperfines (D*−D, B*−B, J/ψ−ηc, Υ−ηb) is excluded by the class-membership criteria of Paper CCXLI §7: the dual-H--heavy class has exactly one occupant in QCD, b̄c, so the framework predicts that the cos(2θG2) expression is realized in Bc alone. The 0.9σ ATLAS agreement is the first empirical test of the dual-H- class and of Theorem 6.1. 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.