The scintillation yields of ZnWO4 crystals change depending on the incident direction of particles. This property can be used as a direction-sensitive dark matter detector, so we investigated the ZnWO4 light yields ratio of neutron-induced nuclear recoils to gamma-ray-induced electron recoils (quenching factor). Two surfaces almost perpendicular to the crystal axis of ZnWO4 were irradiated with a quasi-monochromatic neutron beam of 0.885 MeV, and the quenching factors of both surfaces for the oxygen-nucleus recoil in the ZnWO4 crystal were measured. The obtained quenching factors of the two surfaces were 0.235 ± 0.026 and 0.199 ± 0.020, respectively, confirming 15.3% anisotropy.
ASJC Scopus subject areas
- Physics and Astronomy(all)