摘要
用 NaI 晶体探测器所获取的γ谱可被分解为全能峰,水平连续区和康普顿散射区三个分量.在对 NaI 响应函数的研究工作中,首先用蒙特卡罗方法对晶体中的单次、二次和三次康普顿散射进行拟合.经过改进的函数其参数的物理意义明确,易于在拟合中选取初值.用所选取的总响应函数对6英寸×6英寸的圆柱形NaI 所获取的^(137)的γ谱所作的拟合取得了令人满意的结果.
The gamma spectrum collected with NaI detector can be resolved into the full ener- gy peak,the flat continuum,and Compton scattering components.In our study, Monte Carlo simulation on the single,double and triple Compton Scattering in NaI crystal are made to investigate their characteristics,therefore a suitable function has been adopted for the fitting of total Compton scattering.The parameters in the modified function have explicit physical meanings,and therefore are easy to be given the initial values for fitting.Satisfactory results have been obtained in the fitting of an experimental spectrum collected by a 6″×6″Nal detector with ^(137)Cs using the selected total response function.
关键词
NAI
探测器
响应函数
康普顿散射
NaI detector
monte Carlo simulation
response function
Compton scatering
fitting
