Annealing behavior of copper after low temperature neutron irradiation

During an isochronal annealing program Huang and asymptotic diffuse x-ray scattering were measured along with the changes in the lattice parameter and electrical resistivity of copper single crystals after neutron irradiation at 4.60K. Between 30 and 400K the interstitial clusters change from ''cloud-like'' to loop configurations. At 700K the loops consist of approximately 90 interstitial atoms and have diameters of about 30 A. The loop size increases with annealing temperature, the loop size distribution broadens. At 3000K the rms number of interstitials per loop is square root of z2 approximately 330. At 1500K also vacancy loops are formed