期望最大法用于脉冲γ射线解谱的理论模拟与分析  

Simulation and Analysis of Spectrum Reconstruction of Pulsed γ-Rays Using Expectation Maximization Method

作　　者：王继虎[1] 马文彦[1] 翁秀峰[2] 宋朝晖[2] 祝杰[2] 施帅 

机构地区：[1]第二炮兵工程大学,西安710049 [2]西北核技术研究所,西安710024

出　　处：《现代应用物理》2014年第3期169-173,共5页Modern Applied Physics

基　　金：国家自然科学基金资助项目(11375145)

摘　　要：分析了衰减透射法测量脉冲γ射线能谱的原理,理论模拟了衰减透射法能谱探测过程,使用期望最大法对模拟结果进行了能谱重建,分析了重建初始谱及测量噪声对解谱结果的影响。结果表明,期望最大法能较好地解出基于衰减透射数据的脉冲γ能谱;测量噪声水平在1%以内,算法具有较强的鲁棒性。The attenuated transmission method for spectral estimation of pulsedγ-rays is de-scribed.The transmission of laser-acceleratedγ-rays passing through the aluminum and lead attenuators was simulated by Monte Carlo method.Theγ-ray spectra were reconstructed by expectation-maximization（EM） method according to the transmission data from the simula-tion.The accuracy and robustness of the method were investigated with regard to the meas-urement errors and random Gaussian noise under different initial guesses.The results show that the EM method is robust to reconstruct spectra close to the truth when the noise level is less than 1%.

关 键 词：期望最大法 脉冲γ射线 能谱重建 

分 类 号：O434.1[机械工程—光学工程]