Study of generation of secondary electrons and radiation defects in alkali halides irradiated with swift electrons

Abstract

Abstract The delta-electron generation by primary electrons with energies from 1.0 to 10 MeV in various absorbers was simulated for one dimensional geometry by the use of the “segments model”. The depth distribution of moderated electrons and radiation damage in model alkali halide absorbers were calculated. In experiments the depth profiles of colour centre density in KCI and NaCl crystals, irradiated with 1.0 and 2.0 MeV electrons at the incidence angle θ = 0° 20° 45° were measured. The integral dose of incident beam was varied from 1.1014 to 6.1015 cm−2. The depth density of colour centres is found to be determined by the moderated delta-electron distribution for irradiation doses smaller than 1015 cm−2. Along the <100> direction of KCI and NaCl crystals a distinct anisotropy of depth colouration profiles as well as F- and M-centre density distributions is observed.