Scintillation Characteristics of Indium Doped Cesium Iodide Single Crystal

Abstract

Indium doped cesium iodide (CsI:In) single crystals were grown by the Bridgman method. A comparison study of the scintillation properties of our CsI:In and commercially available CsI:Tl single crystals was carried out, including scintillation decay time, energy resolution, non-proportionality, absolute light yield, and afterglow. Under X-ray excitation, the CsI:In emission corresponds to a symmetrical broad band centered at 545 nm. Its scintillation decay time is <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$1.99 \pm 0.02~\mu\hbox{s}$</tex> </formula> at room temperature under <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$^{137}{\rm Cs}\gamma $</tex></formula> -ray excitation. The CsI:In light yield was found to be <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex Notation="TeX">$34,700 \pm 1735$</tex></formula> photons per MeV with an energy resolution of <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$9.1 \pm 0.3\% $</tex></formula> , based on the pulse height spectra under <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$^{137}{\rm Cs}$</tex></formula> excitation. The afterglow level of CsI:In over 130 ms after pulsed X-ray excitation was two orders of magnitude higher than that of CsI:Tl.