Synthetic spodumene polycrystals as a TL dosimetric material

Synthetic ββ-spodumene polycrystals were produced by a devitrification method, undoped and doped with controlled concentration of the Ce3+Ce3+ or Mn2+Mn2+ impurities. The TL properties of these polycrystals and of a colourless natural spodumene were investigated. Some dosimetric properties of them were also discussed. The dopants do not affect the TL peak position with respect a pure ββ-spodumene sample but the intensity of the TL peaks at 180 and 280∘C is improved in the Ce-doped one. The Ce3+Ce3+ ions do not participate in the TL light emission; on the other hand, the presence of Mn2+Mn2+ ions cause an emission band around 600–650 nm in the TL light emission spectrum. The emission around 400 nm appears in the TL emission spectrum of all the samples and it is believed to correspond to aluminium centre ([AlO4/hole]0) recombination with an electron. The more sensitive samples to γγ-radiation are the colourless natural spodumene and the Ce-doped synthetic spodumene, respectively. The colourless natural spodumene crystal shows a TL peak at 180∘C suitable for dosimetry, while for Ce-doped ββ-spodumene sample the TL peaks at 180 and 280∘C can be used. No fading of the TL emission was observed for Ce-doped ββ-spodumene sample up to 80 days after irradiation.