Development of Neutron Detector Based on Gd₃Ga₃Al₂O₁₂:Ce Single Crystals

Abstract

Single crystals of Gd <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> Ga <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">12</sub> :Ce were grown successfully and a slice having thickness lesser than 1 mm was processed from the grown crystals to setup a portable thermal neutron detector. The presence of Gd isotopes having very high thermal neutron capture cross section ensures almost 100% stopping efficiency in such a low thickness. On the other hand, a lower thickness provided a better discrimination from gamma background. In addition to the continuum gamma, Gd isotopes also produce low-energy conversion electrons and X-rays which could be successfully observed in the form of well discriminated photopeaks at 34 and 74 keV. These photopeaks could also be measured in nuclear reactor beam lines with high gamma background.