openmc.data – Nuclear Data Interface

Core Classes

The following classes are used for incident neutron data, decay data, fission and product yields.

IncidentNeutron

Continuous-energy neutron interaction data.

Reaction

A nuclear reaction

Product

Secondary particle emitted in a nuclear reaction

FissionEnergyRelease

Energy relased by fission reactions.

DataLibrary

Collection of cross section data libraries.

Decay

Radioactive decay data.

FissionProductYields

Independent and cumulative fission product yields.

WindowedMultipole

Resonant cross sections represented in the windowed multipole format.

ProbabilityTables

Unresolved resonance region probability tables.

The following classes are used for storing atomic data (incident photon cross sections, atomic relaxation):

IncidentPhoton

Photon interaction data.

PhotonReaction

Photon-induced reaction

AtomicRelaxation

Atomic relaxation data.

The following classes are used for storing thermal neutron scattering data:

ThermalScattering

A ThermalScattering object contains thermal scattering data as represented by an S(alpha, beta) table.

ThermalScatteringReaction

Thermal scattering reaction

CoherentElastic

Coherent elastic scattering data from a crystalline material

IncoherentElastic

Incoherent elastic scattering cross section

Core Functions

atomic_mass

Return atomic mass of isotope in atomic mass units.

atomic_weight

Return atomic weight of an element in atomic mass units.

combine_distributions

Combine distributions with specified probabilities

decay_constant

Return decay constant of isotope in [s^-1]

decay_energy

Get decay energy value resulting from the decay of a nuclide

decay_photon_energy

Get photon energy distribution resulting from the decay of a nuclide

dose_coefficients

Return effective dose conversion coefficients from ICRP-116

gnd_name

Return nuclide name using GND convention

half_life

Return half-life of isotope in seconds or None if isotope is stable

isotopes

Return naturally occurring isotopes and their abundances

kalbach_slope

Returns Kalbach-Mann slope from calculations.

linearize

Return a tabulated representation of a one-variable function

thin

Check for (x,y) points that can be removed.

water_density

Return the density of liquid water at a given temperature and pressure.

zam

Return tuple of (atomic number, mass number, metastable state)

One-dimensional Functions

Function1D

A function of one independent variable with HDF5 support.

Tabulated1D

A one-dimensional tabulated function.

Polynomial

A power series class.

Combination

Combination of multiple functions with a user-defined operator

Sum

Sum of multiple functions.

Regions1D

Piecewise composition of multiple functions.

ResonancesWithBackground

Cross section in resolved resonance region.

Angle-Energy Distributions

AngleEnergy

Distribution in angle and energy of a secondary particle.

KalbachMann

Kalbach-Mann distribution

CorrelatedAngleEnergy

Correlated angle-energy distribution

UncorrelatedAngleEnergy

Uncorrelated angle-energy distribution

NBodyPhaseSpace

N-body phase space distribution

LaboratoryAngleEnergy

Laboratory angle-energy distribution

AngleDistribution

Angle distribution as a function of incoming energy

EnergyDistribution

Abstract superclass for all energy distributions.

ArbitraryTabulated

Arbitrary tabulated function given in ENDF MF=5, LF=1 represented as

GeneralEvaporation

General evaporation spectrum given in ENDF MF=5, LF=5 represented as

MaxwellEnergy

Simple Maxwellian fission spectrum represented as

Evaporation

Evaporation spectrum represented as

WattEnergy

Energy-dependent Watt spectrum represented as

MadlandNix

Energy-dependent fission neutron spectrum (Madland and Nix) given in ENDF MF=5, LF=12 represented as

DiscretePhoton

Discrete photon energy distribution

LevelInelastic

Level inelastic scattering

ContinuousTabular

Continuous tabular distribution

CoherentElasticAE

Differential cross section for coherent elastic scattering

IncoherentElasticAE

Differential cross section for incoherent elastic scattering

IncoherentElasticAEDiscrete

Discrete angle representation of incoherent elastic scattering

IncoherentInelasticAEDiscrete

Discrete angle representation of incoherent inelastic scattering

MixedElasticAE

Secondary distribution for mixed coherent/incoherent thermal elastic

Resonance Data

Resonances

Resolved and unresolved resonance data

ResonanceRange

Resolved resonance range

SingleLevelBreitWigner

Single-level Breit-Wigner resolved resonance formalism data.

MultiLevelBreitWigner

Multi-level Breit-Wigner resolved resonance formalism data.

ReichMoore

Reich-Moore resolved resonance formalism data.

RMatrixLimited

R-matrix limited resolved resonance formalism data.

ResonanceCovariances

Resolved resonance covariance data

ResonanceCovarianceRange

Resonace covariance range.

SingleLevelBreitWignerCovariance

Single-level Breit-Wigner resolved resonance formalism covariance data.

MultiLevelBreitWignerCovariance

Multi-level Breit-Wigner resolved resonance formalism covariance data.

ReichMooreCovariance

Reich-Moore resolved resonance formalism covariance data.

ParticlePair

SpinGroup

Resonance spin group

Unresolved

Unresolved resonance parameters as identified by LRU=2 in MF=2.

ACE Format

Classes

ace.Library

A Library objects represents an ACE-formatted file which may contain multiple tables with data.

ace.Table

ACE cross section table

ace.TableType

Type of ACE data table.

Functions

ace.ascii_to_binary

Convert an ACE file in ASCII format (type 1) to binary format (type 2).

ace.get_libraries_from_xsdir

Determine paths to ACE files from an MCNP xsdir file.

ace.get_libraries_from_xsdata

Determine paths to ACE files from a Serpent xsdata file.

ENDF Format

Classes

endf.Evaluation

ENDF material evaluation with multiple files/sections

Functions

endf.float_endf

Convert string of floating point number in ENDF to float.

endf.get_cont_record

Return data from a CONT record in an ENDF-6 file.

endf.get_evaluations

Return a list of all evaluations within an ENDF file.

endf.get_head_record

Return data from a HEAD record in an ENDF-6 file.

endf.get_tab1_record

Return data from a TAB1 record in an ENDF-6 file.

endf.get_tab2_record

endf.get_text_record

Return data from a TEXT record in an ENDF-6 file.

NJOY Interface

njoy.run

Run NJOY with given commands

njoy.make_pendf

Generate pointwise ENDF file from an ENDF file

njoy.make_ace

Generate incident neutron ACE file from an ENDF file

njoy.make_ace_thermal

Generate thermal scattering ACE file from ENDF files