Thermoluminescence properties of rare earth doped lithium magnesium borate phosphors

This paper reports the thermoluminescence (TL) properties of rare earth doped lithium magnesium borate (LMB) polycrystalline phosphor. LMB phosphor has been prepared by high temperature solid state diffusion method. Among all the rare earth doped LMB phosphors, terbium doped material has shown maximum TL sensitivity with a broad dosimetric glow peak at 240 °C. near the tissue equivalent TL phosphor with terbium dopant has about four times the TL sensitivity of TLD-100. The main dosimetric properties such as glow curve stability, TL response versus absorbed dose, post-irradiation storage stability, and reusability are investigated. This TL material has a linear dose response up to 10³ Gy, negligible storage fading and a simple annealing procedure for reuse. The TL emission spectra of LMB:Tb³⁺ showed broad green emission at 544 nm, which merged with host emission. The characteristic Tb³⁺ emissions are seen in the photoluminescence (PL) spectra.