Optically stimulated luminescence in KMgF3:Ce3+ . Comparison of dosimetric characteristics with Al2O 3:C

KMgF₃ crystals doped with Ce³⁺ have been investigated as a new material for dosimetry of ionizing radiation. Earlier researches have shown their thermoluminescence (TL) properties. The present work shows that this compound can also be read out by optical stimulation with powerful blue or yellow-green light. The sensitivity has been evaluated and found to be one order of magnitude higher than that of Al₂O₃:C which can be considered as the standard dosimetric material based on Optically Stimulated Luminescence (OSL). The higher sensitivity is for the greater part due to the larger wavelength difference between stimulation and emission wavelengths resulting in lower detection of scattered light. Time response characteristics are also noteworthy better allowing fast pulsed and multiple readout. Unfortunately, the selfdose (~1.5 μGy/h) due to the presence of intrinsic ⁴⁰K is a major drawback for application of this material in environmental dosimetry. Some features of the mechanism have been studied with different spectroscopic techniques. The luminescent centers have been clearly identified as Ce ³⁺ ions. It has been shown that the main trapping center involved in OSL is the same as that in TL