Die Richtungsabhängigkeit der Szintillations-Lichtausbeute von dünnen Anthrazen- und Stilben-Kristallen beim Beschuß mit α-Strahlen
The scintillation light yield of thin anthracene and stilbene crystals bombarded with α particles of ThB is investigated. A strong dependence of the light yield on the direction of incidence with respect to the crystal axes is found, confirming the results of previous measurements with thick anthracene crystals. For anthracene, maximum light yield occurs for α particles incident approximately parallel to thec′ axis. With stilbene crystals a minimum of the light output is found in thec′ direction. Furthermore, for thin anthracene crystals the direction of maximum light output depends slightly on the crystal thickness.