X-ray-induced thermally stimulated luminescence of cerium-doped gadoliniumoxyorthosilicate

Thermally stimulated luminescence from X-irradiated Gd2SiO5:Ce, measured in the interval 300-700 K, is characterized by a main glow peak near 390 K an d weaker maxima near 420, 490 and 550 K. Analysis of the well-resolved prin cipal peak shows that it obeys first-order kinetics with thermal activation energy 1.16 eV and frequency factor 3.17 x 10(14) s(-1). The glow curve an d peak parameters are similar to those found in cerium-doped M2SiO5 (M = Lu , Y, Yb, Er) and undoped Lu2SiO5. For these latter samples, it has previous ly been shown that the defect responsible For the principal peak (similar t o 375 K) is intrinsic and common to these C2/c-structured oxyorthosilicates . The present results demonstrate that the defect is also common to Gd2SiO5 :Ce, which possesses P2(1)/c symmetry, and is likely associated with the co nfiguration of oxygen ions in the vicinity of the host lanthanide ions. An oxygen ion vacancy is a plausible candidate for this defect. (C) 2001 Elsev ier Science Ltd. All rights reserved.