THE STUDY OF NUCLEAR TRACKS IN CRYSTALS

The problem of fast heavy nuclei track registration and track stabilit y in natural and artificial crystals is generally discussed in the fra me of four - zone model of tracks, first suggested in 1972. The result s on sensitivity calibrations of the crystals, the efficiency of parti cle registration, the sources of background, the thermal stability of latent tracks, the uranium content in crystals are reviewed. The data on tracks age and fossil galactic cosmic ray nuclei tracks in crystals provide a very important information about the nucleosynthesis proces ses in our Galaxy, about the history of the Earth and about the charge and energy spectra of cosmic ray nuclei with Z > 26 averaged over tim e intervals up to 200 M.Y. The dependence of volume etchable track len gth (VETL) on threshold annealing procedure and track orientation in c rystal lattice suppose to be very important for fossil and fresh track studies.