
Run the NJOY job, and then look at the resulting output file.
Find the table labeled "thermal quantities at 293.6 K = .0253 eV."
NJOY is often run at temperatures different than the one
corresponding to .0253 eV, and this table is capable of showing
values corresponding to both the temperature used (e.g.,
300K) and the standard value of .0253 eV. The table contains
the simple fission and capture cross sections as evaluated at
"tev" and .0253 eV, and it also contains the Maxwellianweighted
average of these cross sections ("thermal capture integral",
"thermal fission integral"). For 1/v cross section shapes,
these two numbers are proportional, and the "gfactor" listed
is unity. For more general shapes, gfactors different from
unity give a integral measure of how seriously the cross sections
differ from the 1/v shape.
The "capture resonance integral" and the "fission resonance
integral" give the integrated effect of the higher energy data.
The alpha, eta, and K1 integrals are commonly used in thermal
reactor analysis.
