Luminescence study of LiMgBO₃ :Dy for γ-ray and carbon ion beam exposure

LiMgBO₃ :Dy³⁺ , a low Z_eff material was prepared using the solution combustion method and its luminescence properties were studied using X-ray diffraction (XRD), scanning electron microscopy (SEM), thermoluminescence (TL), photoluminescence (PL), Fourier transform infrared spectroscopy, and electron paramagnetic resonance (EPR) techniques. Reitvield refinement was also performed for the structural studies. The PL emission spectra for LiMgBO₃ :Dy³⁺ consisted of two peaks at 478 due to the ⁴ F_9/2 →⁶ H_15/2 magnetic dipole transition and at 572 nm due to the hypersensitive ⁴ F_9/2 →⁶ H_13/2 electric dipole transition of Dy³⁺ , respectively. A TL study was carried out for both the γ-ray-irradiated sample and the C⁵⁺ irradiated samples and was found to show high sensitivity for both. Moreover the γ-ray-irradiated LiMgBO₃ :Dy³⁺ sample showed linearity in the dose range 10 Gy to 1 kGy and C⁵⁺ -irradiated samples show linearity in the fluence range 2 × 10¹⁰ to 1 × 10¹¹ ions/cm² . In the present study, the initial rise method, various heating rate method, the whole glow curve method, glow curve convolution deconvolution function, and Chen's peak shape method were used to calculate kinetic parameters to understand the TL glow curve mechanism in detail. Finally, an EPR study was performed to examine the radicals responsible for the TL process.