Optically based dosimetry of high-energy radiation using the undoped lithium tetraborate crystals: Nonlinear features

The lithium tetraborate (LTB) optical characteristics studies, particularly the luminescence and phosphorescence after irradiation on the M − 30 microtron to create radiation defects, are presented. The investigation was conducted in a wide range of intensities of accelerated electrons, their energies within 7–15 MeV, and absorbed radiation doses. The threshold character and nonlinear influence of the radiation defects on the optical dosimetric characteristics of LTB were established when their concentration became comparable to that of intrinsic or structural defects. Undoped optical crystals LTB are a convenient target for this type of research. It is shown that the combination of optical data from the study of thermally stimulated luminescence and phosphorescence allows one to control the irradiation conditions: flux density and absorbed dose. The obtained results are important for radiation technologies that use high doses of radiation, and can also be taken into account when planning of dosimetric procedures in medicine using high-energy nuclear particles.