Calcium Drip Line Prediction

This pre-print establishes closed-form analytical predictions for the structural and thermodynamic termination of the neutron-rich calcium isotopic chain (Z = 20, N = 40 to 50, A = 60 to 70) utilizing a parameter-free isoscalar variational formalism. Bypassing phenomenological shell-correction fittings, the framework derives explicit, falsifiable numerical thresholds for isotopic binding stability, boundary-layer stress divergence, isoscalar mass residuals, and neutron skin thickness. Key predictions include the absolute unbinding of Ca-70 via boundary-layer cavitation, a sharp laminar cascade termination between Ca-60 and Ca-62, a precise mass residual deviation of 0.7812% for Ca-60, and a neutron skin thickness of 0.342 fm. These metrics provide an immediate, parameter-free falsification benchmark for rare-isotope experimental facilities such as FRIB and RIKEN-RIBF.