X射线探测器的脉冲标定技术

利用强流电子束技术产生通量密度为10¹⁸—10¹⁹X-ray photon/sr·s的脉冲CuKX射线源,标定PIN型硅二极管半导体探测器对X光子的脉冲灵敏度。用绝对X射线监测器——P10气体脉冲电离室作为脉冲X射线通量密度的标准。脉冲电荷自动测量仪由微处理机进行程序控制,并予以实时校准。该电离室测量通量密度的精度为±5％,适用的能通量率范围可达4×10^-9—2×10²W/cm²,适用的光子能量范围为1.5—10keV,标定探测器的精度为±7.0％,并发现PIN型硅二极管的脉冲灵敏度比稳态X射线束标定的灵敏度高30％左右。关键词：

PULSE CALIBRATION TECHNIQUE OF X-RAY DETECTOR

A pulsed CuK X-ray source with flux intensity 10¹⁸-10¹⁹ K X-rays per sr per s has been produced using high current electron beam technique, it has been employed to calibrate the response of the silicon PIN diode detector to pulsed X-ray photon. An absolute X-ray monitor——P10 gas pulse ionization chamber has been used as a standard of the pulsed X-ray flux density, the automatic pulsed charge measuring instrument is controlled and Corrected in real time by a microcomputer. The measured uncertainty of the flux density is ±5%. This chamber is suitable for the range of energy flux rate 4×10^-9-2×10² W/cm² and the range of photon energy 1.5-10 keV. The calibrated accuracy of the detector is ±7.0%. It is found that the pulsed sensitivity of the silicon PIN diode is about 30% higher than the sensitivity calibrated by a steady X-ray beams.