Radiation Hardening

A single-event upset is a transient bit flip caused by charge deposition from ionizing radiation at a sensitive node. Radiation hardening is the direct engineering countermeasure to that mechanism, not an adjacent control: it raises the critical charge required to flip a node and so attacks the technique's defining physical precondition rather than its consequences. This is the strongest pairing in the batch because the technique and the control describe the same phenomenon from opposite sides.