ENDF-6 Formats Manual Data Formats and Procedures for the Evaluated Nuclear Data File ENDF/B-VI and ENDF/B-VII

In December 2006, the Cross Section Evaluation Working Group (CSEWG) of the United States released the new ENDF/B-VII.0 library. This represented considerable achievement as it was the 1st major release since 1990 when ENDF/B-VI has been made publicly available. The two libraries have been released in the same format, ENDF-6, which has been originally developed for the ENDF/B-VI library. In the early stage of work on the VII-th generation of the library CSEWG made important decision to use the same formats. This decision was adopted even though it was argued that it would be timely to modernize the formats and several interesting ideas were proposed. After careful deliberation CSEWG concluded that actual implementation would require considerable resources needed to modify processing codes and to guarantee high quality of the files processed by these codes. In view of this the idea of format modernization has been postponed and ENDF-6 format was adopted for the new ENDF/B-VII library. In several other areas related to ENDF we made our best to move beyond established tradition and achieve maximum modernization. Thus, the 'Big Paper' on ENDF/B-VII.0 has been published, also in December 2006, as the Special Issue of Nuclear Data Sheets 107 (1996) 2931-3060. The new web retrieval and plotting system for ENDF-6 formatted data, Sigma, was developed by the NNDC and released in 2007. Extensive paper has been published on the advanced tool for nuclear reaction data evaluation, EMPIRE, in 2007. This effort was complemented with release of updated set of ENDF checking codes in 2009. As the final item on this list, major revision of ENDF-6 Formats Manual was made. This work started in 2006 and came to fruition in 2009 as documented in the present report.