Effect of Ca doping on the structure and scintillation properties of ZnWO4

✍ Scribed by Kraus, H. ;Mikhailik, V. B. ;Vasylechko, L. ;Day, D. ;Hutton, K. B. ;Telfer, J. ;Prots, Yu.

• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: English
• Weight: 284 KB
• Volume: 204
• Category: Article
• ISSN: 0031-8965
• DOI: 10.1002/pssa.200622331

✦ Synopsis

Abstract

The future application of ZnWO~4~ scintillator in a cryogenic search for rare events is the motivation for optimization of this material. We present results on the effect of Ca doping on the structure and scintillation properties of ZnWO~4~. X‐ray diffraction analysis revealed that there is no mixing in the CaWO~4~–ZnWO~4~ pseudobinary system due to a significant mismatch of the crystal structures of CaWO~4~ and ZnWO~4~. The lattice parameters of Ca‐doped ZnWO~4~ samples obtained from X‐ray powder diffraction data confirmed this finding. It is also shown that ZnWO~4~ retains the monoclinic wolframite structure when cooling, at 12 K exhibiting the following lattice parameters: a = 4.6826(2) Å, b = 5.7088(2) Å, c = 4.9230(2) Å and β = 90.541(2)°. The scintillation light yield of the Zn~1−x~ Ca__~x~__ WO~4~ was measured using the multi‐photon counting technique and it is found that small concentrations of Ca (x = 0.001 – 0.02) cause no deterioration of this parameter. Ca doping of ZnWO~4~ is expected to facilitate production of a single‐crystalline scintillator. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)