Precise measurement of the scintillation decay constant of ZnWO${}_4$ crystal

Abstract

The scintillation decay time constant of a ZnWO${}_4$ crystal irradiated with $\alpha$-particles from ${}^{241}$Am was precisely investigated, and was found to depend on the incident direction of the $\alpha$-particles on the crystal. The longest decay time constant ($24.3\pm 0.6\mu$s) was obtained on the surface perpendicular to the b-axis of the crystal (Surface B). On Surfaces A and C, the decay constants were $20.0$ and $21.3\pm 0.2\mu$s, respectively. The scintillation yield of the ZnWO${}_4$ was also anisotropic and depended on the incident direction of the heavy particles. The maximum yield was achieved on surface B, suggesting a correlation between the light yield and scintillation decay time constant of ZnWO${}_4$ crystals.

9 pages, 8 figures, Accepted for PTEP

References in corpus (5)

• ZnWO_4 crystals as detectors for double beta decay and dark matter experiments
• Radioactive contamination of ZnWO4 crystal scintillators
• Improvement of radiopurity level of enriched ${}^{116}$CdWO${}_4$ and ZnWO${}_4$ crystal scintillators by recrystallization
• Measurements of anisotropic scintillation efficiency for carbon recoils in a stilbene crystal for dark matter detection
• Measurements of ZnWO${}_4$ anisotropic response to nuclear recoils for the ADAMO project