Optimization of light collection from crystal scintillators to search for dark matter and 2 β decay

Cryogenic scintillation bolometers are promising instruments to search for dark matter and neutrinoless double β decay. Energy resolutions and relative pulse amplitudes of scintillation detectors using ZnWO4 scintillation crystals of different shape (cylinder and hexagonal prism), reflector materials and shapes, optical contact and surface properties were measurement. For experimental conditions typical for operating cryogenic scintillating bolometer the best energy resolution and relative pulse amplitude was obtained for a hexagonal shape scintillator with diffuse side and polished face surfaces, surrounded by a reflector with a gap between the scintillator and the reflector