O‘zmu xabarlari Вестник нууз acta nuuz

Conclusion. As a result of fast neutron irradiation of nominally pure LuAG with the fluence up to 1017 сm-2, the 
formation of color centers with characteristic optical absorption bands in the 250 nm range of the F-center and in the 295 nm 
range of the hole О‾-center is observed. Regardless of the Pr activator presence the color centers with the 390 nm band of the F+-
center and with the 570 nm band of the electron center are formed. In this case, the peaks at 445, 515 and 545 K with 
characteristic activation energy of 1.34, 1.62 and 1.95 eV are observed on the integral TSL curves. After only γ-irradiation the 
445 K TSL peak is not observed, which is evidence of forming an additional local level in the band gap under neutron irradiation. 
The decrease in the intensity of GL bands of the activator Pr3+ center with the raise in the fast neutron fluence ≥ 1015 сm-2 has 
the following possible explanation: 
- on the one hand, reabsorption of Pr3+ luminescence by color centers (hole O

and electronic F+) is possible within the 
spectral range 300-400 nm, their concentration increases with the raise in neutron fluence; 
- on the other hand, the data on additional γ-quanta irradiation of a neutron-irradiated sample heated up to 605 K lead to 
assuming that a hole is captured by the Pr3+center with the formation of a hole Pr4+ center, as a result of which the 
concentration of the Pr3+ centers decreases and the concentration of the electron F+ and V0(Cimp) centers increases.
The obtained results provide useful information for determining the radiation resistance of optical transparency and 
luminescence centers since a decrease in the light emission and an increase in the after-luminescence amplitude can be controlled 
by defects (impurity and structural) caused by ionizing radiation [1,8-10] and displacements of structure-forming atoms by fast 
neutron fluences ≥ 1015 см-2. 
REFERENCES 
1. M. Nikl, E. Mihokova, V. Laguta, J. Pejchal, S. Baccaro, A. Vedda, Radiation damage processes in complex-oxide 
scintillators. in: Proceedings of SPIE, vol. 6586 2007 p. 6586OE-1-13. 

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