Function cross_sections_at_energy 

pub fn cross_sections_at_energy(
    data: &ResonanceData,
    energy_ev: f64,
) -> CrossSections

Compute cross-sections at a single energy.

Dispatches each resonance range to the appropriate formalism-specific calculator (SLBW, MLBW, Reich-Moore, R-Matrix Limited, URR) based on the formalism stored in that range. See the module-level table for the full dispatch map.

Adjacent ranges that share a boundary energy use half-open intervals [e_low, e_high) so the boundary point is counted exactly once (ENDF-6 §2 convention).

Limitations

MLBW (Multi-Level Breit-Wigner, LRF=2) ranges use true MLBW with interference. formulas as an approximation, ignoring resonance-resonance interference. Results may be inaccurate for closely spaced or overlapping resonances.

Arguments

• data — Parsed resonance parameters from ENDF.
• energy_ev — Neutron energy in eV (lab frame).

Returns

Cross-sections in barns.