核电子学与探测技术
覈電子學與探測技術
핵전자학여탐측기술
NUCLEAR ELECTRONICS & DETECTION TECHNOLOGY
2014年
1期
86-88,116
,共4页
华艳%朱祚缤%刘艺琴%罗小兵
華豔%硃祚繽%劉藝琴%囉小兵
화염%주조빈%류예금%라소병
高纯锗%效率刻度%MCNP%多线法
高純鍺%效率刻度%MCNP%多線法
고순타%효솔각도%MCNP%다선법
HPGe%Efficiency calibration%MCNP%muti-line method
探测效率是高纯锗谱仪的重要性能指标,探测器的效率刻度具有重要的意义。针对新购置的高纯锗谱议,采用多线法和距离变换相结合的实验方法,刻度了高纯锗探测器在不同源距下的全能峰效率曲线,并利用厂家提供的探头结构尺寸,采用MCNP5程序模拟计算了该探测器对不同能量γ射线的全能峰效率。将模拟计算效率和实验效率进行对比,模拟计算的全能峰效率和实验测定的全能峰效率具有一定偏差,经分析偏差主要原因是探测器内部结构尺寸不够精确,通过调节死层厚度和冷指尺寸,使得模拟计算效率和实验效率很好符合。
探測效率是高純鍺譜儀的重要性能指標,探測器的效率刻度具有重要的意義。針對新購置的高純鍺譜議,採用多線法和距離變換相結閤的實驗方法,刻度瞭高純鍺探測器在不同源距下的全能峰效率麯線,併利用廠傢提供的探頭結構呎吋,採用MCNP5程序模擬計算瞭該探測器對不同能量γ射線的全能峰效率。將模擬計算效率和實驗效率進行對比,模擬計算的全能峰效率和實驗測定的全能峰效率具有一定偏差,經分析偏差主要原因是探測器內部結構呎吋不夠精確,通過調節死層厚度和冷指呎吋,使得模擬計算效率和實驗效率很好符閤。
탐측효솔시고순타보의적중요성능지표,탐측기적효솔각도구유중요적의의。침대신구치적고순타보의,채용다선법화거리변환상결합적실험방법,각도료고순타탐측기재불동원거하적전능봉효솔곡선,병이용엄가제공적탐두결구척촌,채용MCNP5정서모의계산료해탐측기대불동능량γ사선적전능봉효솔。장모의계산효솔화실험효솔진행대비,모의계산적전능봉효솔화실험측정적전능봉효솔구유일정편차,경분석편차주요원인시탐측기내부결구척촌불구정학,통과조절사층후도화랭지척촌,사득모의계산효솔화실험효솔흔호부합。
Efficiency is one of the important performance of detector ,and efficiency calibration of detector is very important .According to the need of the HPGe detector which is bought recently , we calibrate the efficiency of HPGe detector with passive and active method .The curves of efficiency of the coaxial HPGe detector with sever-al distances between the radioactive source and the detector are calibrated .Meanwhile, using the dimensions of the detect-head provided by the producer , and using MCNP5 code based on the Monte Carlo method , we sim-ulate and calculate the full -energy efficiency of the γ-ray,establish the MCNP model of the curve of detected efficiency.Then, the calculated values of efficiency with the experimental ones are compared .The simulated efficiency and the experimental efficiency has some deviation , we change the thickness of dead layer and the size of cold-finger, the efficiency curves are more consistent .The results show that when the HPGe detector dead layer thickness is 0.17 cm, the thickness and length of cold -finger size are 0.625 cm and 4.53 cm, The simulated efficiencies are consistent with the experimental ones .