A Model-Based Discovery Framework for Element 120 Using AME2020/NUBASE2020 Nuclear-Systematics Compatibility

Element 120 remains experimentally unobserved, but its nuclear behavior can be investigated through external data-compatibility analysis. This article presents a model-based Element 120 discovery framework centered on the predicted high-stability region Z = 120, N = 184, A = 304. The framework was tested against AME2020 atomic mass systematics and NUBASE2020 nuclear-property evaluation, using local superheavy mass-surface extrapolation and a semi-empirical mass-formula baseline corrected by endpoint residuals. A total of 260 AME2020 superheavy entries with Z >= 100 were parsed and analyzed. Across nine independent extrapolation variants, the predicted binding energy per nucleon for 304120 clustered at 7027.18 +/- 4.53 keV/nucleon, with a range of 7019.90 to 7033.70 keV/nucleon. This convergence indicates external compatibility of the proposed Z = 120, N = 184 nuclear framework with known superheavy mass trends. The result is not an observational synthesis or direct detection of Element 120; rather, it supports a data-compatible, model-based theoretical discovery framework for the Element 120 region.