Effect of thermo-chemical treatments on the luminescence and scintillation properties of CaWO4

• Published in: Optical materials Vol. 30; no. 10; pp. 1630 - 1634
• Main Authors: Yakovyna, V., Zhydachevskii’, Ya, Mikhailik, V.B., Solskii, I., Sugak, D., Vakiv, M.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.06.2008; Elsevier Science
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Exact sciences and technology; Experimental methods and instrumentation for elementary-particle and nuclear physics; Nuclear physics; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Other solid inorganic materials; Photoluminescence; Physics; Radiation detectors, dosimeters; Scintillation detectors; 29.40.Mc; 78.55.Hx; 61.72.Ji; Scintillations; Temperature dependence; Calcium Tungstates; Ternary compounds; Luminescence; Sensor materials; Heat treatments; Medium effect; Temperature effects; Emission spectra; Excitation spectrum; Thermal annealing; Synchrotron radiation
• ISSN: 0925-3467; 1873-1252
• DOI: 10.1016/j.optmat.2007.11.003

In this work, we investigated the influence of thermal annealing in different atmospheres on the luminescence and scintillation properties of CaWO4. Luminescence and luminescence excitation spectra were examined using VUV synchrotron radiation. Thermal treatment causes change of the defect subsystem of the crystal, resulting in the alteration of the spectral dependences. The most obvious effect is the relative change in the intensity of the defect emission band which is excited below the fundamental absorption edge 4.7eV. Studies of the scintillation kinetics and light yield carried out over a temperature range 8–300K showed that former does not change upon the treatment, in contrast to the intensity of scintillations. It is found that ∼50% increase of the scintillation response can be achieved for CaWO4 samples annealed in hydrochloric acid.