1.1 本指南涵盖了ASTM评估的核数据横截面和不确定度文件的建立和使用，用于分析轻水反应堆轻水反应堆压力容器监督（PVS）相关中子场中的单个或多个传感器测量。这些领域包括运行动力反应堆、基准领域和反应堆测试区域的船内和船外监测位置。 1.2 建立ASTM推荐横截面文件的要求涉及数据格式、评估要求、基准字段验证、误差估计评估（协方差文件）和文件。ASTM组件的进一步要求- 当与传感器测量结合并用于确定中子谱时，推荐的横截面文件是其内部一致性。 1.3 使用规范包括适用的能量区域、数据处理要求和不确定性的应用。 1.4 本指南与指南直接相关，应主要与指南结合使用 E482 和 E944 ，和实践 E560 , E185 和 E693 . 1.5 ASTM横截面和不确定度文件表示用于传感器集分析的通用数据集。然而，该数据集的可用性并不排除使用其他经验证的数据，无论是专有数据还是非专有数据。 当使用偏离本标准规定要求的替代横截面文件时，应向剂量测定应用的客户说明这些偏差。 1.6 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、健康和环境实践，并确定监管限制的适用性。 1.7 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认标准化原则制定的。 ====意义和用途====== 4.1 美国的ENDF/B图书馆和其他类似图书馆，如JEFF ( 23 ) ，JENDL ( 21 ) ，和BROND ( 22 ) ，提供中子截面和其他核数据的汇编，供核界使用。这些优秀评估的可用性使标准化使用成为可能，从而允许轻松引用和相互比较计算。然而，随着第一个ENDF/B文件的开发，显然它们并不适合所有应用程序。这一需求导致了专门的ENDF/B剂量学文件的开发 ( 17 , 25 ) ，由对剂量测定应用非常重要的激活截面组成。 该文件在全球范围内可用。后来，引入了其他“特殊用途”文件 ( 26 ) . 在ENDF/B-VI编译中 ( 27 ) ，剂量学文件不再作为单独的评估文件出现。ENDF/B-VII。0编译 ( 28 ) 删除了剂量学界使用的大多数反应特定协方差文件。它将“标准截面”的协方差文件保存在一个特殊的子库中，但该子库中的协方差数据仅在每个反应被视为“标准”的能量范围内提供，不包括LWR-PVS剂量测定应用所需的全部能量范围。后来对ENDF/B版本的更新增加了一些反应通道的协方差文件，但这些协方差文件通常仅基于计算，并不代表用于推导基础ENDF/B截面的方法。 为了满足对特定剂量测定库的需求，国际原子能机构召集了一个协调研究项目（CRP），该项目利用了一组国际专家，以提供一组推荐的剂量测定横截面，并汇编一组支持使用该推荐数据集的验证证据。该文件为国际反应堆剂量测定和聚变文件（IRDFF） ( 19 , 20 ) ，借鉴其他国家核评估，并用国际专家组评估的一系列反应补充这些评估。IRDFF库的开发是为了支持LWR剂量学应用以及超出本标准范围的其他剂量学应用，作为其开发过程的一部分，它包含了在参考和标准基准中子场中获得的验证数据。 一些IRDFF补充反应代表了CSEWG目前正在检查的材料评估，以纳入更新的ENDF/B评估。补充IRDFF评估仅包括剂量学界感兴趣的特定反应，而不是完整的材料评估。在将其包含在主ENDF/B评估库中之前，ENDF社区需要进行完整的评估。 4.2 LWR监测剂量测定的应用引入了新的数据需求，通过创建专用横截面文件可以最好地满足这些需求。该文件应以便于用户应用的形式保存（最少处理）。 文件应继续包含以下类型的信息，或表明应用于补充文件内容的以下类型数据的来源: 4.2.1 LWR环境中裂变、活化、氦产生传感器反应的剂量学截面，以支持辐射测量、固态径迹记录器、氦累积剂量学方法（见测试方法 E853 , E854 , E910 和 E1005年 ). 4.2.2 对主动或被动剂量测量有用的其他横截面或传感器响应函数，例如，使用中子吸收横截面表示由于盖或自身引起的衰减校正- 屏蔽。 4.2.3 用于损伤评估的横截面，例如铁中每个原子的位移（dpa）。 4.2.4 剂量测定所需的相关核数据，如分支比、裂变产额和原子丰度。 4.3 ASTM推荐的横截面和不确定度主要基于IRDFF（1.05版）剂量测定文件。增加了铁等材料的损伤截面，以促进剂量学界报告的dpa测量的标准化。为了确保自一致性，考虑了基准场和反应堆试验区域的积分测量 ( 29 ) . 总剂量测定文件的目的是- 在LWR环境中应用的差分和积分测量尽可能一致。数据文件的这种自一致性对于LWR压力容器监测应用是强制性的，因为只有非常有限的剂量测定数据可用。如果对现有评估横截面进行了修改，以在LWR环境中获得这种自一致性，则应在相关文件中详细说明修改（见 ( 19 , 29 ) ).

1.1 This guide covers the establishment and use of an ASTM evaluated nuclear data cross section and uncertainty file for analysis of single or multiple sensor measurements in neutron fields related to light water reactor LWR-Pressure Vessel Surveillance (PVS). These fields include in- and ex-vessel surveillance positions in operating power reactors, benchmark fields, and reactor test regions. 1.2 Requirements for establishment of ASTM-recommended cross section files address data format, evaluation requirements, validation in benchmark fields, evaluation of error estimates (covariance file), and documentation. A further requirement for components of the ASTM-recommended cross section file is their internal consistency when combined with sensor measurements and used to determine a neutron spectrum. 1.3 Specifications for use include energy region of applicability, data processing requirements, and application of uncertainties. 1.4 This guide is directly related to and should be used primarily in conjunction with Guides E482 and E944 , and Practices E560 , E185 , and E693 . 1.5 The ASTM cross section and uncertainty file represents a generally available data set for use in sensor set analysis. However, the availability of this data set does not preclude the use of other validated data, either proprietary or nonproprietary. When alternate cross section files that deviate from the requirements laid out in this standard are used, the deviations should be noted to the customer of the dosimetry application. 1.6 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. ====== Significance And Use ====== 4.1 The ENDF/B library in the United States and similar libraries elsewhere, such as JEFF ( 23 ) , JENDL ( 21 ) , and BROND ( 22 ) , provide a compilation of neutron cross section and other nuclear data for use by the nuclear community. The availability of these excellent evaluations makes possible standardized usage, thereby allowing easy referencing and intercomparisons of calculations. However, as the first ENDF/B files were developed it became apparent that they were not adequate for all applications. This need resulted in the development of the specialized ENDF/B Dosimetry File ( 17 , 25 ) , consisting of activation cross sections important for dosimetry applications. This file was made available worldwide. Later, other “Special Purpose” files were introduced ( 26 ) . In the ENDF/B-VI compilation ( 27 ) , dosimetry files no longer appeared as separate evaluation files. The ENDF/B-VII.0 compilation ( 28 ) removed most of the reaction-specific covariance files used by the dosimetry community. It kept the covariance files for the “standard cross sections” in a special sub-library, but the covariance data in this sub-library are only provided over the energy range in which each reaction is considered to be a “standard”, and does not include the full energy range required for LWR PVS dosimetry applications. Later updates to the ENDF/B releases added covariance files for some reaction channels but these covariance files were often based solely on calculations and were not representative of the methodology used to derive the underlying ENDF/B cross section. In response to the need for a dosimetry-specific library, the International Atomic Energy Agency convened a Coordinated Research Project (CRP) that drew upon the set of international experts to provide a recommended set of dosimetry cross sections and to compile a set of validation evidence that supported the use of this recommended dataset. This file, the International Reactor Dosimetry and Fusion File (IRDFF) ( 19 , 20 ) , draws upon other national nuclear evaluations and supplements these evaluations with a set of reactions evaluated by expert international groups. The IRDFF library was developed to support the LWR dosimetry application as well as other dosimetry applications that go beyond the scope of this standard and, as part of its development process, it incorporates validation data acquired in reference and standard benchmark neutron fields. Some of the IRDFF supplemental reactions represent material evaluations that are currently being examined by the CSEWG for inclusion within updated ENDF/B evaluations. The supplemental IRDFF evaluations only include the specific reactions of interest to the dosimetry community and not a full material evaluation. The ENDF community requires a complete evaluation before including it in the main ENDF/B evaluated library. 4.2 The application to LWR surveillance dosimetry introduced new data needs that can best be satisfied by the creation of a dedicated cross section file. This file shall be maintained in a form designed for easy application by users (minimal processing). The file shall continue to incorporate the following types of information or indicate the sources of the following type of data that should be used to supplement the file contents: 4.2.1 Dosimetry cross sections for fission, activation, helium production sensor reactions in LWR environments in support of radiometric, solid state track recorder, helium accumulation dosimetry methods (see Test Methods E853 , E854 , E910 , and E1005 ). 4.2.2 Other cross sections or sensor response functions useful for active or passive dosimetry measurements, for example, the use of neutron absorption cross sections to represent attenuation corrections due to covers or self-shielding. 4.2.3 Cross sections for damage evaluation, such as displacements per atom (dpa) in iron. 4.2.4 Related nuclear data needed for dosimetry, such as branching ratios, fission yields, and atomic abundances. 4.3 The ASTM-recommended cross sections and uncertainties are based mostly on the IRDFF (version 1.05) dosimetry files. Damage cross sections for materials such as iron have been added in order to promote standardization of reported dpa measurements within the dosimetry community. Integral measurements from benchmark fields and reactor test regions have been considered in order to ensure self-consistency ( 29 ) . The total dosimetry file is intended to be as self-consistent as possible with respect to both differential and integral measurements as applied in LWR environments. This self-consistency of the data file is mandatory for LWR-pressure vessel surveillance applications, where only very limited dosimetry data are available. Where modifications to an existing evaluated cross section have been made to obtain this self-consistence in LWR environments, the modifications shall be detailed in the associated documentation (see ( 19 , 29 ) ).