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user’s MCROSS library, required if the PEACO routine is used by IC5=±2. The
selection IC8=3 is usually recommended.
= 0 between 130.07 eV and the thermal-cut-off energy with lethargy interval
of Δu=0.00125
= 1 between 130.07 eV and the thermal-cut-off energy with lethargy interval
of Δu=0.00125 and between 961.12 eV and 130.07 eV with lethargy
interval of Δu=0.000625
= 2 between 961.12 eV and the thermal-cut-off energy with uniform lethargy
interval of Δu=0.0005
= 3 between 130.07 eV and the thermal-cut-off energy with lethargy interval
of Δu=0.0005 and between 961.12 eV and 130.07 eV with lethargy
interval of Δu=0.00025
[cf.] Sect.1.3, Sect.1.6, Sect.1.10
IC9
Indicator to call the HOMOSP routine to calculate the one point (bare) reactor
neutron spectrum and k ∞ , k eff in the fixed source problem (IC2>0). Enter IC9=0 in
the eigenvalue problem mode.
= 0 Skip
= ± 1 P 1 approximation
= ± 2 B 1 approximation
= ± 11 Critical buckling search by P 1 approximation
= ± 12 Critical buckling search by B 1 approximation
Note:
If negative value is entered, P 0 components of the solution of P 1 or B 1 equations
are used as the weight to collapse the homogenized cross-sections, i.e. the leakage
effect is reflected on the spectrum by the geometrical buckling value. If positive
value is entered, the spectrum obtained by the cell calculation is used for
collapsing.
The CPM is carried out upon infinite cell approximation. The geometrical
buckling is used to reflect the leakage effect on the spectrum by use of the
HOMOSP routine.
If IC9=±1 or =±2 is entered, the geometrical buckling given in Block-4 is used
in P 1 /B 1 equations. If IC9=±11 or =±12 is entered, the geometrical buckling is
obtained so that the k eff is unity. The use of the critical buckling search option
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