Effect of gamma-induced defects on the activator glow in Lu-=SUB=-2-=/SUB=-SiO-=SUB=-5-=/SUB=- : Ce scintillator crystals

Correlations were studied between the optical absorption (OA) spectra and integral curves of thermal glow (TG) in 300-600 K after irradiation Lu 2 SiO 5 : Ce scintillation crystals with 60 Co gamma-quanta (1.17 1.33 MeV) at dose rate 1.1 Gy/s range 70-5·10 7 Gy 310 their gamma-luminescence (GL). There are intrinsic defects caused by technological process, such as neutral V O5 -centers OA band 193 nm charged =Si-V --- 213 nm, Lu1-F^+-Si 238 3+ /Ce 4+ 263 /F 295 centers. Irradiation to 5·10 4 resulted decreasing -center concentration, but did not influenced on others. While, doses >5·10 concentrations all other mentioned grew. The observed recovery decrease TG peak 335 ageing time (1, 3 10 hours) 305 K, also correlated growth 540 serial irradiations from 70 2.3·10 6 due releasing electrons these color centers followed radiative recombination Ce1-centers. However GL yield 400 420 >10 is possible related increasing O4 , centers, which compete Ce1 ones trapping electrons. Thus, upper limit for stable gamma-scintillation Gy. Keywords: Ce, gamma-induced luminescence, limit.