Abstract
A low-neutron D–³He generator that closes its power balance on measured component efficiencies, with every extrapolation beyond demonstrated hardware named rather than hidden. Introduces a new physics result — the synchrotron effective harmonic cutoff scales with machine size — and states its single largest open requirement (end-plug density) plainly, including a companion structural gate on the plug winding.
This paper is Open Access (CC BY 4.0). Every headline number regenerates from the named script and archived data in the deposit above; requirement-class assumptions and open risks are stated in the manuscript rather than absorbed into a single optimum. No financial or commercial information appears in this work.