AbstractIt is estimated that one could anticipate as many as 10% supra thermonuclear neutrons, of energy as high as 20 MeV, for each thermonuclear neutron, from an optically thick d-t core of a typical inertial fusion energy (IFE) reactor target (ϱR ≥ 3 g cm−2). This high energy neutron tail generated in an IFE target opens up additional threshold reaction channels leading to enhanced activation of the target, the surrounding reactor blanket and the shield. For example, SiC activation increases by as much as six orders of magnitude when supra thermonuclear neutrons are accounted for. It is recommended to validate the conclusions of the present studies experimentally through D-T shots at NOVA and the planned NIF facility at Lawrence Livermore National Laboratory.