Single Crystal Growth, Optical Properties and Neutron Response of ${\rm Ce}^{3+}$ Doped ${\rm LiCaAlF}_{6}$

Abstract

Ce2%: <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sup> LiCaAlF <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sub> ( <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sup> LiCAF) single crystal (nominal composition) with 2 mm in diameter and 50 mm in length was grown by the micro-pulling-down method. Emission from the perturbed Ce <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3+</sup> centers was observed in an ¿-ray excited radioluminescence. The neutron response was compared with Li-glass (GS20, Saint-Gobain) using <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">252</sup> Cf. The scintillation decay time of Ce2%: <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sup> LiCAF is 38 nsec, which is twice as short as that of GS20. Using Hamamatsu photomultiplier H7416 the photoelectron yield about a half of that of GS20 has been measured for the Ce: <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sup> LiCAF single crystal . Considering the light yield of GS20 (6000 phot/neutron) and the spectral correction due to the different emission peak position in both materials, the light yield of Ce: <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sup> LiCAF single crystal is estimated about 4200 phot/neutron.