openmc.data.MultiLevelBreitWigner

class openmc.data.MultiLevelBreitWigner(target_spin, energy_min, energy_max, channel, scattering)[source]

Multi-level Breit-Wigner resolved resonance formalism data.

Multi-level Breit-Wigner resolved resonance data is identified by LRF=2 in the ENDF-6 format.

Parameters:
  • target_spin (float) – Intrinsic spin, \(I\), of the target nuclide
  • energy_min (float) – Minimum energy of the resolved resonance range in eV
  • energy_max (float) – Maximum energy of the resolved resonance range in eV
  • channel (dict) – Dictionary whose keys are l-values and values are channel radii as a function of energy
  • scattering (dict) – Dictionary whose keys are l-values and values are scattering radii as a function of energy
Variables:
  • atomic_weight_ratio (float) – Atomic weight ratio of the target nuclide given as a function of l-value. Note that this may be different than the value for the evaluation as a whole.
  • channel_radius (dict) – Dictionary whose keys are l-values and values are channel radii as a function of energy
  • energy_max (float) – Maximum energy of the resolved resonance range in eV
  • energy_min (float) – Minimum energy of the resolved resonance range in eV
  • parameters (pandas.DataFrame) – Energies, spins, and resonances widths for each resonance
  • q_value (dict) – Q-value to be added to incident particle’s center-of-mass energy to determine the channel energy for use in the penetrability factor. The keys of the dictionary are l-values.
  • scattering_radius (dict) – Dictionary whose keys are l-values and values are scattering radii as a function of energy
  • target_spin (float) – Intrinsic spin, \(I\), of the target nuclide
classmethod from_endf(ev, file_obj, items)[source]

Create MLBW data from an ENDF evaluation.

Parameters:
  • ev (openmc.data.endf.Evaluation) – ENDF evaluation
  • file_obj (file-like object) – ENDF file positioned at the second record of a resonance range subsection in MF=2, MT=151
  • items (list) – Items from the CONT record at the start of the resonance range subsection
Returns:

Multi-level Breit-Wigner resonance parameters

Return type:

openmc.data.MultiLevelBreitWigner