ASTM E481-16
用钴和银的放射性测定中子积分通量率的试验方法
Standard Test Method for Measuring Neutron Fluence Rates by Radioactivation of Cobalt and Silver
ASTM E481-16 发布历史
ASTM E481-16由美国材料与试验协会 US-ASTM 发布于 2016。
ASTM E481-16在国际标准分类中归属于: 17.240 辐射测量。
ASTM E481-16 发布之时，引用了标准
- ASTM E170 有关辐射测量和剂量测定的标准术语
- ASTM E177 进行室外噪声测量的测量方案的拟定用标准指南
- ASTM E181 放射性核素探测器的校准和分析的标准试验方法
- ASTM E261 用放射性技术测定中子的积分通量率、积分通量和中子波谱
- ASTM E262 用放射性技术测定热中子反应和积分通量率的试验方法
ASTM E481-16的历代版本如下：
- 2016年 ASTM E481-16 用钴和银的放射性测定中子积分通量率的试验方法
- 2015年 ASTM E481-15 通过钴和银的放射性测量中子注量率的标准试验方法
- 2010年 ASTM E481-10 钴和银放射性活化法测定中子注量率的标准试验方法
- 2003年 ASTM E481-03 用钴和银的放射性测定中子积分通量率的标准试验方法
- 1997年 ASTM E481-97 用钴和银的放射性测定中子积分通量率的试验方法
3.1 This test method uses one monitor (cobalt) with a nearly 1/v absorption cross-section curve and a second monitor (silver) with a large resonance peak so that its resonance integral is large compared to the thermal cross section. The pertinent data for these two reactions are given in Table 1. The equations are based on the Westcott formalism ((2, 3) and Practice E261) and determine a Westcott 2200 m/s neutron fluence rate nv0 and the Westcott epithermal index parameter . References (4, 5, and 6) contain a general discussion of the two-reaction test method. In this test method, the absolute activities of both cobalt and silver monitors are determined. This differs from the test method in the references wherein only one absolute activity is determined.
(A) The numbers in parenthesis following given values are the uncertainty in the last digit(s) of the value; 0.729 (8) means 0.729 ± 0.008, 70.8(1) means 70.8 ± 0.1.(B) A 2200 m/s cross section (E = 0.0253 eV, T = 20°C) was taken from the sources indicated in Ref (9).(C) Cross section uncertainty data is taken from Ref (7) , the cross section comes from the other reference.(D) Calculated using Eq 10.(E) Cross section uncertainty comes from covariance data provided in the cross section source. The other reference indicates the source of the cross section.(F) In Fig. 1, Θ = 4ErkT/AΓ 2 = 0.2 corresponds to the value for 109Ag for T = 293 K, ∑r = N0σr, max. σr, max=29999 barn at 5.19 eV (