【摘要】 收集了Fe从1keV～20MeV能区中子总截面实验激发函数,择优推荐了该能区2277个能点上的σ_t^Fe数据;同时,收集了Al从4.07keV～20MeV能区中子总截面实验激发函数曲线,择优推荐了该能区1302个能点上的σ_t^Al;还特意推荐了Fe在keV能区的中子总截面最小值。此外,还简要讨论了Fe和Al两种核素的中子总截面共振结构问题。为了建立中重核中子总截面实验编评工作特有的规范,认真总结了30年代至70年代这50多年间有关Fe和Al两种核素的全部中子总截面实验工作。针对中重核中子总截面共振结构绸密的特点,提出了优选σ_t的两个判据:σ_t的精确度与中子源的相关性;σ_t的准确度与中子谱仪分辨率的相关性。更多还原

【Abstract】 The experimental data of total cross section were collected and evaluated for natural iron in the energy region from IkeV to 20MeV and for natural aluminium from 4. 07keV to 20MeV. The evaluated data were recommended in the regions for them. The minimum values of Fe total cross section in the keV region were special- ly recommended. The resonance structures were briefly discussed for both Fe and Al. To make the evaluation better,all experimental measurements of neutron total cross section relative to Fe and Al were studied. Considering the resonance feature of medium weight nuclides, two criterions for selecting total cross section were presented; l)the correlation between the precission of total cross section and neutron source;2)the correlation between the accuracy of total cross section and the resolving power of the neutron spectrometer.更多还原