Nuclear Technology / Volume 168 / Number 2 / November 2009 / Pages 279-283
Neutron Data / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 2) / Radiation Measurements and Instrumentation
The European Activation System, EASY, includes as the source of nuclear data the European Activation File (EAF). A new version of EAF, EAF-2007, has been developed that contains cross-section data for deuteron- and proton-induced reactions in addition to the traditional neutron-induced data. The main reason for the addition of these data to EAF is to enable activation calculations to be performed for the International Fusion Materials Irradiation Facility, which is a planned materials test facility, and for other accelerator-driven devices with an incident upper energy limit of 60 MeV. EAF-2007 has benefited from the generation and maintenance of comprehensive activation files and the development of the processing code SAFEPAQ-II. Cross-section validation exercises against both experimental data and systematics, which were started on the EAF-4 file (1995), enable a comprehensive assessment of the data. Although EAF-2007 is the best-validated activation neutron cross-section library in the world, currently <3% of all the reactions can be compared with experimental information and sometimes then only for a very limited, and not always relevant, energy range. As with EAF-2001, EAF-2003, and EAF-2005, results of integral experiments have been used to correct, adjust, and validate data. This can be done using SAFEPAQ-II by inputting the measured effective cross sections. Validation using integral data has been performed by means of direct comparison with measurements of various materials under relevant neutron spectra. A tool has been recently developed that is of importance now that libraries contain so much calculated data. Statistical Analysis of Cross Sections is used to look for trends in the library data for a particular reaction type, and this has proved efficient in identifying reactions with data that need correction or improvement. This method has been used with EAF-2005 and EAF-2007 and is a valuable additional validation method.