Physics Add Ons To PENDF Tapes

There are a number of physical quantities that can be computed from ENDF data, but that are not explicitly included in most ENDF files. NJOY uses its data-flow model to generate such quantities and add them to a PENDF tape. Several of these physical quantities will be discussed in the following pages:
  • Gas-production cross sections (sometimes called charged-particle production) are produced by the GASPR module and add to File 3 of a PENDF tape using the MT numbers from 203 (H-1 production) to 207 (He-4 production). These cross sections are normally sums over several of the reactions found on a normal ENDF-format evaluation.

  • Heating and radiation damage cross sections are generated by the HEATR module and added to File 3 of a PENDF tape using special MT numbers. Values of 300+MT are used to represent heating associated with MT; normally only MT=301 for total heating is given. A special value of MT=444 is used for total radiation damage energy production, and some other values nearby are used for the components of damage, if desired.

  • Thermal scattering cross sections that take the binding of the target atom into account are produced in the THERMR module. Results are added to both File 3 (cross sections) and File 6 (energy-angle distributions) using a special set of MT numbers including MT=221 for free gas scattering, MT=222 for hydrogen bound in water, and higher MT values for other important moderating materials.
The modular nature of the NJOY data-flow model allows you to include these additional physical quantities or omit them, depending on the needs of your particular applications.


23 January 2013 T-2 Nuclear Information Service