Welcome to the Los Alamos National Laboratory (LANL) distribution site for nuclear data libraries. These libraries contain A Compact ENDF (ACE) files that have been processed using the nuclear data processing code NJOY ( Compressed folders with each nuclear data library are downloadable for use in your own applications.

    Library Types

    • ACE Continuous-energy data for use in codes like MCNP®.

      For information on how to install the libraries, please see our Installing ACE Libraries page.


    If you have any questions regarding the nuclear data libraries found here or if there are problems with this site, please contact the Los Alamos National Laboratory, Nuclear Data Team,