Annealing Process in Neutron-Irradiated LiF

Abstract

LETTERS TO THE EDITOR 603 be expected from the uncertainties in both the theory and the experiment.Work has been done on a number of other materials including MnO, Cr 2 0 3 , and ZnFe 2 0 4 and is being continued with a view to studying the dependence of the energy distribution on the temperature, the angle of scattering, and the degree of magnetic order. An account of this work will be submitted to the Canadian Journal of Physics. Energy distributions of neutrons scattered by vanadium metal under several different conditions have been measured by the author with results in agreement with the theory. This work is being continued with a view to obtaining the frequency distribution of the normal modes in vanadium metal.

Formation of the defect halo of swift heavy ion tracks in LiF due to spatial redistribution of valence holes

“…But such increase of the irradiation temperature can accelerate diffusion of only H‐centers 15. Diffusion of F‐centers in LiF is frozen up to temperatures ≈420 K 23 due to the high value of their migration barrier ( U F = 1.5 eV 11, 29, 30). Therefore, diffusion of F‐color centers during track relaxation can not describe the difference between the initial radial distribution of valence holes and the radial distribution of F‐centers detected in LiF crystals irradiated at the room temperature.…”

Color centers in neutron-irradiated Y3Al5O12, CAF2 and LiF single crystals

“…2, where the optical absorption increases with reactor neutron fluence. The evolution of color center concentration N with the temperature is given by the following expression [1]:…”

“…In the case of ionic crystals, the color centers induced by irradiation by lowly and highly ionizing radiation (electrons, g-rays, neutrons and swift heavy ions) has been well studied by means of several techniques [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16]. These defects may be F-centers (an electron trapped by an anion vacancy), or aggregate centers (F 2 , F 3 , F 4 ) or alkali colloids.…”

Li colloids formation study induced by reactor neutrons in LiF single crystals

“…Bouchaala et al have calculated a value of 1.5 eV for F-type centers activation energy [24]. It is interesting to note that the same value (1.5 eV) was measured a long time ago by analyzing the lattice expansion evolution with annealing temperature in neutron irradiated LiF [25].…”