1.1 本指南涵盖了用于电子半导体器件辐射硬度测试的中子谱调整技术中使用的中子活化探测器材料的选择和使用。描述了在许多辐射硬度测试设施中使用的传感器，并在表脚注中提供了根据其横截面精度、作为传感器的易用性和过去的成功应用判断的每个反应的适当性的评论。本指南还讨论了在选择传感器厚度、传感器盖和传感器位置时需要考虑的注量均匀性、中子自屏蔽和注量衰减校正。 这些考虑与从TRIGA型和Godiva型反应堆等组件以及从加利福尼亚辐射器中确定中子光谱有关。本指南也可适用于20 MeV以下的其他广泛能源分配源。 注1: 有关本指南中使用的术语的定义，请参阅术语 E170 . 1.2 本指南还涵盖了激活箔和其他传感器的γ射线或β射线发射率的测量，以及这些箔的绝对比活度的计算。主要的测量技术是高分辨率伽马射线光谱法。活动用于确定能量- 中子源的注量谱。请参阅指南 E721 . 1.3 测量和分析详情如下: 1.3.1 测量传感器活动所涉及的校正包括伽马射线探测器校准中的有限传感器尺寸和厚度、脉冲高度分析仪死区时间和脉冲堆积损耗以及背景放射性。 1.3.2 本指南和试验方法中考虑了使用二次标准γ射线发射源的探测器校准的主要方法 E181 . 此外，指南中还讨论了在基准中子场的已知频谱中激活传感器的替代方法 E1018 . 1.3.3 提出了一种数据分析方法，该方法考虑了以下因素:探测器效率；背景减法；辐照、等待和计数时间；裂变产额和γ射线分支比；以及传感器中伽马射线和中子的自吸收。 1.4 以国际单位制表示的数值应视为标准值。本标准不包括其他计量单位。 1.5 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全和健康实践，并确定监管限制的适用性。 ====意义和用途====== 3.1 由于中子活化测量中使用的材料种类繁多，因此本指南旨在提高此处特定关注领域的均匀性:主要在关键装配反应堆环境中进行电子器件的硬度测试。 注2: 讨论的一些技术对14 MeV剂量测定有用。见测试方法 E496 适用于14 MeV中子效应测试的活化探测器材料。 注3: 本指南中推荐的材料适用于 252 Cf或其他弱源效应测试，前提是通量足以产生可数活动。 3.2 本指南分为两个重叠主题；用于传感器选择的标准，以及用于确保正确确定中子谱测定活动的程序。参见术语 E170 和试验方法 E181 . 指南中讨论了利用活化传感器数据确定中子谱 E721 和 E944 .

1.1 This guide covers the selection and use of neutron-activation detector materials to be employed in neutron spectra adjustment techniques used for radiation-hardness testing of electronic semiconductor devices. Sensors are described that have been used at many radiation hardness-testing facilities, and comments are offered in table footnotes concerning the appropriateness of each reaction as judged by its cross-section accuracy, ease of use as a sensor, and by past successful application. This guide also discusses the fluence-uniformity, neutron self-shielding, and fluence-depression corrections that need to be considered in choosing the sensor thickness, the sensor covers, and the sensor locations. These considerations are relevant for the determination of neutron spectra from assemblies such as TRIGA- and Godiva-type reactors and from Californium irradiators. This guide may also be applicable to other broad energy distribution sources up to 20 MeV. Note 1: For definitions on terminology used in this guide, see Terminology E170 . 1.2 This guide also covers the measurement of the gamma-ray or beta-ray emission rates from the activation foils and other sensors as well as the calculation of the absolute specific activities of these foils. The principal measurement technique is high-resolution gamma-ray spectrometry. The activities are used in the determination of the energy-fluence spectrum of the neutron source. See Guide E721 . 1.3 Details of measurement and analysis are covered as follows: 1.3.1 Corrections involved in measuring the sensor activities include those for finite sensor size and thickness in the calibration of the gamma-ray detector, for pulse-height analyzer deadtime and pulse-pileup losses, and for background radioactivity. 1.3.2 The primary method for detector calibration that uses secondary standard gamma-ray emitting sources is considered in this guide and in Test Methods E181 . In addition, an alternative method in which the sensors are activated in the known spectrum of a benchmark neutron field is discussed in Guide E1018 . 1.3.3 A data analysis method is presented which accounts for the following: detector efficiency; background subtraction; irradiation, waiting, and counting times; fission yields and gamma-ray branching ratios; and self-absorption of gamma rays and neutrons in the sensors. 1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. ====== Significance And Use ====== 3.1 Because of the wide variety of materials being used in neutron-activation measurements, this guide is presented with the objective of bringing improved uniformity to the specific field of interest here: hardness testing of electronics primarily in critical assembly reactor environments. Note 2: Some of the techniques discussed are useful for 14-MeV dosimetry. See Test Method E496 for activation detector materials suitable for 14-MeV neutron effects testing. Note 3: The materials recommended in this guide are suitable for 252 Cf or other weak source effects testing provided the fluence is sufficient to generate countable activities. 3.2 This guide is organized into two overlapping subjects; the criteria used for sensor selection, and the procedures used to ensure the proper determination of activities for determination of neutron spectra. See Terminology E170 and Test Methods E181 . Determination of neutron spectra with activation sensor data is discussed in Guides E721 and E944 .