CsI(Tl)闪烁体是X光转换为可见光的一个比较重要的部件, 其转换效率对惯性约束聚变中的X光诊断发挥关键作用。利用北京同步辐射装置4B7A中能束线, 针对2 000~2 800 eV能段的软X光入射不同厚度CsI(Tl)闪烁体后转换为可见光的探测效率进行了标定。文章详细分析了CsI(Tl)闪烁体在X 光激发下的能量沉积和出射可见光的效率。整个探测系统包括入射兼容光源、标准探测器、快门、CsI(TI)闪烁体块、黑腔盒, SI1000可见光CCD等。用曲线拟合的方法归一化入射兼容光, 利用SI1000可见光CCD 相机作接收系统记录出射可见光, 在CCD线性工作范围内, 得到CCD上记录的出射可见光计数。标定实验获得2 000~2 800 eV能区标定探测器电流, CCD计数, 得到了同一曝光时间下CCD计数和入射光子数的比值, 即探测效率。实验结果表明, 随着CsI(Tl)闪烁体厚度的增加, 探测效率也随之提高。实验方法为后续选择合适厚度闪烁体做软X光探测做基础。

CsI(Tl) scintillator is a key part for the transition from X-ray to visible light, its transition efficiency is of crucial importance in X-ray diagnosis for inertial confined fusion. X-rays could deposit energies into the CsI(Tl) scintillator and visible lights were emitted. The detection efficiency of CsI(Tl) scintillator with different thickness was calibrated on the beamline 4B7A at Beijing Synchrotron Radiation Facility in the energy range between 2 000 eV and 2 800 eV. Energy deposition and energy response with the stimulation of X-ray were studied. The whole system included emitting X-ray, standard detector, shutter, CsI(Tl) scintillator, black box and SI1000 CCD. Emitting X-ray was normalized with curve fitting. SI1000 CCD was used to receive the visible light which the counts were kept in the linearity range of CCD. The experiment gets the detector current, CCD counts, the ratio of CCD counts and emitting X-ray counts in the energy region from 2 000 eV to 2 800 eV. The results show the detection efficiency increase with the increase of the thickness of CsI(Tl) scintillator. The experimental method makes foundation for the subsequent selection of a suitable thickness of scintillator of soft X-ray detection.