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CsI에 활성제로 Li, K, Rb를 첨가하여 CsI(Li), CsI(K) 및 CsI(Rb) 단결정을 Czochral-ski방법으로 육성하였다. 137Cs(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 γ선 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%) 섬광체의 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 τ1 =41.2 ns, τ2=483 ns, τ1=47.2 ns, τ2=417 ns 및 τ1=41.3 ns, τ2=553 ns이였다. 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.


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 137Cs(0.662 MeV), respectively. The energy calibration curves of CsI(Li), CsI(K) and CsI(Rb) scintillators were linear for γ-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 τ1 =41.2 ns and τ2=483 ns, respectively. The fluorescence decay times of CsI(K:0.5 mole%) scintillator were τ1=47.2 ns and τ2=417 ns. And the fluorescence decay times of CsI(Rb:1.5 mole%) scintillator were τ1=41.3 ns and τ2=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.