尖峰脉冲成形算法改进与性能分析  

Improvement and performance analysis of cusp-like pulse shaping algorithm

作　　者：范新洋 王敏[1] 洪旭[1] 杨体波 廖光辉 欧阳周璇 FAN Xinyang;WANG Min;HONG Xu;YANG Tibo;LIAO Guanghui;OUYANG Zhouxuan(College of Nuclear Technology and Automation Engineer,Chengdu University of Technology,Chengdu 610059,China)

机构地区：[1]成都理工大学核技术与自动化工程学院,成都610059

出　　处：《核技术》2021年第1期57-63,共7页Nuclear Techniques

基　　金：国家自然科学基金(No.11975060);国家重点研发计划课题(No.2018YFC0603304);国家科技重大专项专题(No.2017ZX05019001-007)资助。

摘　　要：在数字化核仪器中,为获取高能量分辨率的能谱,常采用数字滤波成形算法处理核脉冲信号,脉冲成形方法中成形参数对输出信号波形、堆积脉冲分离的影响研究鲜有报道。本文在尖峰脉冲成形算法基础上,引入平顶参数,对Mn样品的硅漂移探测器得到的实测脉冲信号开展实验研究,并与常见的梯形脉冲成形方法作对比分析。对采集到的核脉冲信号分别采用尖峰脉冲成形、梯形脉冲成形,然后进行幅度甄别,获取能谱信息,研究相同达峰时间下两种方法对计数率与能量分辨率的影响规律。结果表明:尖峰脉冲成形下降沿快、脉冲宽度窄、较三角脉冲成形更易于分离堆积脉冲;在相同达峰时间下,梯形脉冲成形较尖峰脉冲成形在能量分辨率上更具优势,而尖峰脉冲成形在高计数率上表现出更好的性能。[Background]Digital shaping algorithms are widely applied to improving the energy resolution of digital nuclear instruments.[Purpose]This work aims to improve and analyze the performance of cusp-like shaping algorithm for digital nuclear signal with emphasis on the influence of shaping parameters on the shape of the shaped pulse.[Methods]Based on the peak pulse forming algorithm,flat-top parameter was introduced into cusp-like pulse shaping algorithm.The fast silicon drift detector(FAST-SDD)detector produced by Amptek company was employed to measure the pulse signal obtained from manganese sample,the effect of shaping parameters on the shape of the output signal and the separation of pile-up pulses were investigated by the cusp-like pulse shaping method,and compared with the common trapezoidal pulse shaping methods.In addition,Cusp-like shaping and trapezoidal pulse shaping were used for the sampled nuclear pulse signals,and then amplitude discrimination was performed to obtain energy spectrum information.Finally,the influences of the two methods on the counting rate and energy resolution of the same time were studied.[Results]The results show that the cusp-like pulse shaping has a fast falling edge and a narrow pulse width,makes it easier to separate the pile-up pulses than triangle pulse shaping.[Conclusions]Under the same peak time,trapezoidal pulse shaping has more advantages in energy resolution than cusp-like shaping,while cusp-like pulse shaping shows better performance in count rate.

关 键 词：数字化核仪器 尖峰脉冲成形 能量分辨率 堆积脉冲 

分 类 号：TL822.6[核科学技术—核技术及应用]