スチルベン単結晶の育成

抄録

Growth of stilbene single crystal from melt by Bridgman method is described; scintillation behavior of the grown crystal for various high energy radiations is studied.
Temperature of the furnace around the glass tube in which the crystal is grown is maintained by control within ±0.1°C of fluctuation and the rate of growth is set at 4cm/day. The glass tube has a capillary at its bottom and a single crystal of 2.5 cm in both diameter and height is obtained in the tube. As the melting temperature is rather low, cracking by thermal contraction is less marked in comparison with the case of anthracene. The crystal obtained is colorless and very transparent.
Fluorescence efficiency for high energy radiation is 67% of that of anthracene. Spectral resolu tion for the peak by recoil electrons from Csla7 is 15%. When Sr⁹⁰ is used, spectrum by β3-rays from Sr⁹⁰ is shadowed by spectrum by β-rays from Y⁹⁰ and therefore is not observed.
In conclusion, despite excellent transparency, stilbene is inferior to anthracene in many respects as regards scintillation behavior.