摘要
核爆后其放射性元素种类复杂、量少,用NaI(Tl)γ谱仪监测时,多种核素峰重叠在能谱的散射区内难以识别,因此对谱仪的稳定性,能量分辨率,解谱技术以及最小可探测活度有很高的要求.本文通过实验和MCNP模拟,分析了对某NaI(Tl)γ谱仪探测限的影响因素以及降低探测限的措施,提出了通过屏蔽来降低本底,提高其最小可探测活度的方法,实验表明,通过选择合理的屏蔽尺寸,有效的降低了本底,提高了谱仪的低水平放射性监测能力.
The radioelement species is complex and quantity is few after nuclear explosion,thus it is hard to tell the difference when using the Nal（TI） Gamma spectrometer detection due to several kinds of the peak of nuclide overlapped in the scattering region.So there is a high demand for spectrometer stability,energy resolution,solution spectrum and minimum detective activity.The paper analysed the influenced factors to Nal（TI） Gamma spectrometer and the measures of detection limit decrease by experiments and MCNP simulation,which proposed the methods to reduce background through shielding in order to improve minimum detective activity.The experiment shows that choosing reasonable shielding can reduce the background effectively and improve the spectrometer low level radioactive detect ability.
出处
《南华大学学报（自然科学版）》
2011年第1期6-9,共4页
Journal of University of South China：Science and Technology
