ACE Cross Sections

This module is for reading ACE-format cross sections. ACE stands for “A Compact ENDF” format and originated from work on MCNP. It is used in a number of other Monte Carlo particle transport codes.

ACE-format cross sections are typically generated from ENDF files through a cross section processing program like NJOY. The ENDF data consists of tabulated thermal data, ENDF/B resonance parameters, distribution parameters in the unresolved resonance region, and tabulated data in the fast region. After the ENDF data has been reconstructed and Doppler-broadened, the ACER module generates ACE-format cross sections.

For a complete specification for the classes in the ace module, please refer to the Library Reference entry for ACE Cross Sections – pyne.ace.

Example Use of Library Class

To load data from an ACE file, one needs to simply initialize an instance of the Library class specifying the path to the Library file.

In [1]: from pyne import ace

In [2]: libFile = ace.Library('endf70a')

In [3]: libFile.read()