Around 1960, ENDL (Evaluated Neutron Data Library) was created to store the binary collisional data in a computer readable format for nuclear calculations. One of its main advantages is that it is in pointwise data. It was designed for use in FORTRAN codes and thus was fixed place and hard to read. In addition, it is stored in a directory structure with each actual "data" containing header information.
There is a current effort to clean up the format of ENDL. The first step was to combine some older databases into one larger database. This was successful and over time, more LLNL data may be added to the ENDL database so it is all kept uniform and consistent. The next steps will be to make it free formatted and ultimately make the data available in XML format.
Since ENDL is pointwise data, it is relatively easy to plot and manipulate. It should be very useful for codes that need nuclear or atomic data and do not wish to process ENDF data. With the effort to translate ENDF to ENDL underway, it will also be possible to compare the two neutron libraries to each other in a more consistent manner.
UCRL-WEB-207296