Resolved resonances are obviously fully described in the pointwise cross sections, properly broadened at the given temperature. In the resolved resonance energy range self-shielding is automatically accounted for. For materials with no unresolved resonance regions, no further consideration is required. When unresolved resonance regions (URR's) are present, even pointwise cross sections have a problem with self-shielding. In order to solve this issue, offline generated statistical distributions of cross sections are sampled from at run-time. This procedure is implemented in the FLUKA pointwise approach, and therefore partial or full self-shielding is automatically assured in all conditions and energy ranges.
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