Study of elimination of defects induced by heavy nuclei fission fragments in thin near-surface layers of mica

In the experiments with mica (muscovite) irradiated with heavy nuclei fission fragments, the minimum chemical etching time tau0 was measured after which fission-fragment-created tracks are etched and become visible in an optical microscope. It is established that tau0 depends on the fragment +ncident angle THETA and energy E and on the annealing temperature T of the irradiated samples. Tau0 increases with THETA and T and decreases with E. The regularities of tau0(THETA, T, E) imply that at normal ambient pressure the elimination of defects created by fission fragments occurs with a higher rate in a near-surface layer approximately 0.1 μk thick than in a volume