The thermostimulated exoelectron emission of NaF:U,Me compounds after electron beam irradiation

Abstract

The thermostimulated exoelectron emission (TSEE) of NaF:(U,Me) compounds after electron beam irradiation in the 300-800 K temperature range has been investigated. For NaF:(U,Me) bulk, fiber and nanocrystals several regular peaks of TSEE have been found. Additional effects with the sign of thermostimulated explosive electron emission have been found too. The nature of TSEE process is discussed.1 Introduction Study of thermoactivated processes in irradiated insulating materials [1-3] is very interesting for both fundamental research (study of absorption and distribution of charge and energy of primary beam, autolocalization of holes, generation and recombination of zone and quasi-free electrons, holes and excitons, study of traps ionization and generation of current carriers in strong electrical fields, study of collision ionization of donor levels and electron output into vacuum, study of the influence of crystal's defects on the processes of energy dissipation and light-reserving), and practice (development of storage thermoactivation and photoactivation detectors of ionizing radiations). Different dimensional modifications of (Li,Na)F crystals are most comfortable model objects for basic-applied researches due to their simple cubic structure. In this work the systematic researches of thermostimulated exoelectron emission (TSEE) and thermostimulated luminescence (TSL) of bulk, fiber and nano-sized NaF crystals and compounds on their base have been made. Results of the investigations including effects with the sign of thermostimulated explosive electron emission have been found out.