The JEFF-3.1.1 library is an updated version of the JEFF-3.1 Joint Evaluated File for Fission and Fusion. It consists of sets of evaluated nuclear data for reactor applications. Reliable data of this sort are necessary to improve the safety and economy of existing installations, as well as for the design and efficient operation of advanced nuclear reactors. The improvements in this latest version of the JEFF-3.1.1 library are particularly noteworthy as regards light water reactor applications and the associated fuel cycle.
The present report provides detailed information on the analysis and incremental validation process employed with regard to the JEF-2.2 library, which has provided the basis for the JEFF-3.1.1 library.