1、探測器自身放射性本底CsI crystalCsI Powder21/22/1111ttteaea脈沖形狀甄別脈沖形狀甄別 PSDPulse Shape DiscriminationiiiAtAtQuenching factor (ionization yield energy)thReeREoutputeeoutputRREeRREELLLL溝道效應DAMA/LIBRA NaI(Tl) Scintillator at Gran Sasso : total 0.82 ton-year dataObserve annual modulation in the 2-6 keV single-hit

2、signal band, total 11 cycles, 8s s Reject gamma by PSDNo modulations at higher energy & for multiple-hits December30 km/s 232 km/s60 June30 km/sNaI晶體晶體實驗實驗multiple-hits residual rate (green points) vs single-hit residual rate (red points) Single-Hit Power Spectrum Single Hit 2-6 keV Signal Regio

3、n DAMA/NaI (7 years) + DAMA/LIBRA (4 years) Total exposure: 300555 kg day = 0.82 ton yr表 4-1： 各種常用閃爍體的性能比較 材料 最強發光 波長(nm) 發光衰減時間 折射率 密度 (g/cm3) 光產額 (光子/MeV) NaI(Tl) 410 0.23s 1.85 3.67 42000 CsI(Tl) 565 1.0s 1.79 4.51 55000 ZnS(Ag) 450 0.2s 2.4 4.09 8Li(Eu) 480 1.4s 1.95 4.08 Li 玻璃 395.9 75ns 1.53 2

4、.5 BGO 480 0.3s 2.15 7.13 8900 BaF2 310 6s/ 0.6ns 1.56 4.89 9900 CWO 500 5s 2.3 7.9 19700 蒽 447 30ns 1.62 1.25 芪 410 4.5ns 1.63 1.16 液體閃爍體 420 2.44ns 1.52 0.9 HP Ge detector / PC Ge detectorHigh efficiencyHigh resolution Large massPure materialLow noise/ Low threshold ?10-710-610-610-510-3h lifetime

5、 (s) h?10-810-510-610-610-3e lifetime (s) e70040010100440,000h mobility h(cm2/Vs)110080001000110010040,000e mobility e(cm2/Vs)0.140.090.190.08Fano factor4.24.64.44.22.97e-h pair creation energy (eV)1.61.431.571.502.130.74Band gap (eV)13, 5131, 3348, 30, 5248, 5280, 5332Atomic numberAlSbGaAsCdZnTeCdT

6、eHgI2Ge (77K)Material?10-710-610-610-510-3h lifetime (s) h?10-810-510-610-610-3e lifetime (s) e70040010100440,000h mobility h(cm2/Vs)110080001000110010040,000e mobility e(cm2/Vs)0.140.090.190.08Fano factor4.24.64.44.22.97e-h pair creation energy (eV)1.61.431.571.502.130.74Band gap (eV)13, 5131, 3348

7、, 30, 5248, 5280, 5332Atomic numberAlSbGaAsCdZnTeCdTeHgI2Ge (77K)MaterialSemiconductor detector materialsHPGeHPGe 的體積，質量最大的體積，質量最大( Kg)( Kg)HPGeHPGe 的能量分辨最好的能量分辨最好三種三種HPGeHPGe探測器探測器planarCoaxial detectorVbp (n)p+ (n+)n+ (p+)S0S1pPCGe detector反沖電子或核的次級電子空穴的收集形成信號反沖電子或核的次級電子空穴的收集形成信號- VQtCharge induct