Journal of Sensor Science and Technology (센서학회지)

The Korean Sensors Society (한국센서학회)
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Scintillation Characteristics of CsI:X(X=Li+,K+,Rb+ Single Crystals

CsI:X(X=Li+,K+,Rb+단결정의 섬광특성

  • Published : 2003.01.30
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Abstract

CsI single crystals doped with lithium, potassium or rubidium were grown by using Czochralski method at Ar gas atmosphere. The energy resolutions of CsI(Li:0.2 mole%), CsI(K:0.5 mole%) and CsI(Rb:1.5 mole%) scintillators were 14.5%, 15.9% and 17.0% for $^{137}Cs$(0.662 MeV), respectively. The energy calibration curves of CsI(Li), CsI(K) and CsI(Rb) scintillators were linear for $\gamma$-ray energy. The time resolutions of CsI(Li:0.2 mole%), CsI(K:0.5 mole%) and CsI(Rb:1.5 mole%) scintillators measured by CFT(constant-fraction timing method) were 9.0 ns, 14.7 ns and 9.7 ns, respectively. The fluorescence decay times of CsI(Li:0.2 mole%) scintillator had a fast component and slow one of ${\tau}_1=41.2\;ns$ and ${\tau}_2=483\;ns$, respectively. The fluorescence decay times of CsI(K:0.5 mole%) scintillator were ${\tau}_1=47.2\;ns$ and ${\tau}_2=417\;ns$. And the fluorescence decay times of CsI(Rb:1.5 mole%) scintillator were ${\tau}_1=41.3\;ns$ and ${\tau}_2=553\;ns$. The phosphorescence decay times of CsI(Li:0.2 mole%), CsI(K:0.5 mole%) and CsI(Rb:1.5 mole%) scintillators were 0.51 s, 0.57 s and 0.56 s, respectively.

CsI에 활성제로 Li, K, Rb를 첨가하여 CsI(Li), CsI(K) 및 CsI(Rb) 단결정을 Czochralski방법으로 육성하였다. $^{137}CS$(0.662 MeV)에 대한 CsI(Li:0.2 mole%) 섬광체의 에너지 분해능은 14.5%이었고 CsI(K:0.5 mole%) 섬광체는 15.9%이었으며 CsI(Rb:1.5 mole%) 섬광체는 17.0%이였다. 이들 CsI(Li), CsI(K) 및 CsI(Rb) 섬광체의 $\gamma$선 에너지에 대한 에너지 교정곡선은 선형적 이였다. 일정비율 시간분석법(CFT :constant-fraction timing method)으로 측정한 CsI(Li:0.2 mole%), CsI(K:0.5 mole%) 및 CsI(Rb:1.5 mole%) 성광체의 시간 분해능은 각각 9.0 ns, 14.7 ns 및 9.7 ns이였다. CsI(Li:0.2 mole%), CsI(K:0.5 mole%) 및 CsI(Rb:1.5 mole%) 섬광체의 형광감쇠시간은 각각 ${\tau}_1=41.2\;ns$, ${\tau}_2=483\;ns$, ${\tau}_1=47.2\;ns$, ${\tau}_2=417\;ns$ 및 ${\tau}_1=41.3\;ns$ 및 ${\tau}_2=553\;ns$이였다. 그리고 CsI(Li:0.2 mole%), CsI(K:0.5 mole%) 및 CsI(Rb:1.5 mole%) 단결정의 인광감쇠시간은 각각 0.51 s, 0.57 s 및 0.56 s이였다.

Keywords

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