α粒子散射对爆炸物检测时间分辨的影响  

Influence of scattering α particle on time spectra in explosive detection

作　　者：何铁[1] 陈渊[1] 安力[1] 郭海萍[1] 郑普[1] 王新华[1] 

机构地区：[1]中国工程物理研究院核物理与化学研究所,四川绵阳621900

出　　处：《强激光与粒子束》2010年第10期2437-2440,共4页High Power Laser and Particle Beams

摘　　要：对爆炸物检测中伴随α粒子技术的时间谱进行了研究,建立了一套基于伴随α粒子技术的时间谱测量装置,分析了影响时间谱分辨的若干因素。采用60μm厚的铜箔设计了一个锥形准直筒对散射的α粒子进行屏蔽,以500 g尿素为样品测量了α-γ符合时间谱。结果表明,α粒子在靶室内壁的散射是影响时间谱分辨的重要因素,锥形准直筒抑制了与α散射相关中子产生的γ射线,提高了α-γ符合时间谱的分辨。在有无锥形准直筒的条件下,符合时间谱特征瞬发峰γ的半高宽分辨力分别为1.8 ns和6.4 ns。分辨力高的时间谱可用于获取爆炸物样品的特征瞬发γ能谱。The resolution of time spectrum is an important factor to obtain the excellent prompt gamma spectrum in the explosive detection.In this paper,we consider the scattering of α particle in the D-T reaction chamber wall is the main reason to the resolution of time spectrum.A measured device of time spectra based on associated α particle technique was built.A cone-shaped α particle collimator was designed to restrain the gamma induced by the neutron which is correlated to the scattering α particle.Thus,the resolution of the time spectrum was improved.Measurements show that with and without the collimator,the resolutions of the time spectrum are 1.8 ns and 6.4 ns,respectively.

关 键 词：爆炸物检测 时间谱 伴随α粒子技术 氘氚反应 

分 类 号：O484.41[理学—固体物理]