Joint Evaluated Fission and Fusion (JEFF)
Nuclear Data Library
1982 - To date
1984 - To date
JEFF Reports
1985 - To date

JEFF library releases

The JEFF suite of nuclear data libraries contains a number of different data types, including neutron and proton interaction data, radioactive decay data, fission yields data, and thermal scattering law data.

JEFF-3.3 : Released in November 2017

The JEFF-3.3 nuclear data library has been officially released in November 2017. It includes a thorough update to its neutron, decay data and fission yields library and adopts other sub-libraries (incident proton, alpha, gamma, triton, He-3 and deuteron) from TENDL-2017. Access the JEFF-3.3 release.

JEFF collaboration

The JEFF project meets twice a year, in spring and fall, during the NEA Nuclear Data Week in a 4 to 5 day technical programme, with the aim to promote co-operation between experimentalists, evaluators and end-users of nuclear data involved in both projects.


For more information on JEFF activities please contact the NEA Data Bank Nuclear Data Service team

Last modified: 21 January 2022