Thermoluminescent Response of KMgF3:Yb Single-Crystals in Gamma Radiation Fields

The perovskite-like KMgF<inf>3</inf> shows, when properly doped, thermoluminescence (TL) characteristics that make this phosphor a good candidate for ionising radiation dosimetry. With the purpose of inspecting the dosimetric potentiality of such material, the thermoluminescence emission from irradiated samples of variously doped KMgF<inf>3</inf> in the form of single crystals has been investigated. The features displayed by fluoroperovskite doped with rare earth impurities are particularly promising, in particular Ce and Yb. The results obtained with KMgF<inf>3</inf>:Yb single crystals in particular are described. The TL emission relative to temperature was inspected by means of laboratory-made instrumentation, giving also the possibility of wavelength resolution. The TL emission shows a sharp peak at 410 nm, well centred in the wavelength range of the standard TLD readers; the emission intensity is one order higher than that of TLD-700 chips. The emission was inspected in the dose range from 2 mGy to 20 Gy.