“…Athermal effects can cause defect recovery, strain relaxation, gas and defect diffusion, phase transformations, and gas resolution from bubbles. Such transient irradiation-induced processes are experimentally well documented in the literature for ceramics (Lang 1976, Lomako 1980, Lang 1982, Assmann 1978, Matzke 1983, Matzke 2000, Zinkle 2002) under neutron, fission, ion, electron and laser irradiations. These processes are often referred to as athermal because they are temperature independent or weakly dependent on temperature and cannot be described as thermally activated (activation energies below 0.2 eV).…”