Effect of gamma-irradiation on the photoluminescence of silver-doped lithium triborate glass

Optical-luminescence properties, including absorption spectra, photoluminescence excitation spectra, and changes in photoluminescence spectra after irradiation with γ -rays in the dose range of 1–3 Gy, were measured for novel LiB 3 O 5 :Ag dosimeter glass. A clear dependence of the intensity of the photoluminescence (PL), with a maximum of approximately 300 nm, on the dose value when excited by light with λ exc =220nm was observed. The mechanism of PL in γ -irradiated LiB 3 O 5 :Ag glass is proposed to be a consequence of radiation annihilation with the emission of relaxed exciton-like electronic excitations with the participation of impurity defects (Ag 0 ) in the glass structure. Considering that LiB 3 O 5 has an effective atomic number of Z eff =7.39, which is the closest to Z eff =7.42 of human body tissue, LiB 3 O 5 :Ag glass can be very promising for γ -dosimetry in medical practice during radiation therapy of patients with cancer. The presence of lithium Li(6) and boron B(10) isotopes increases the sensitivity of LiB 3 O 5 :Ag glass to neutrons, which is promising for the manufacture of individual neutron dosimeters for applications in a new field of radiation therapy–neutron therapy.