armi.nucDirectory.nucDir module

Some original nuclide directory code.

Notes

This may be deprecated. Consider using the appropriate instance methods available through the armi.nucDirectory.nuclideBases.INuclide objects and/or the armi.nucDirectory.nuclideBases module.

armi.nucDirectory.nucDir.getNuclideFromName(name)

armi.nucDirectory.nucDir.getNuclidesFromInputName(name)

Convert nuclide specifier strings to isotopically-expanded nuclide bases

armi.nucDirectory.nucDir.getNaturalIsotopics(elementSymbol=None, z=None)

determines the atom fractions of all natural isotopes

Parameters

• elementSymbol (str, optional) – The element symbol, e.g. Zr, U

• z (int, optional) – The atomic number of the element

Returns

abundances – A list of (A,fraction) tuples where A is the mass number of the isotopes

Return type

list

armi.nucDirectory.nucDir.getNaturalMassIsotopics(elementSymbol=None, z=None)

return mass fractions of all natural isotopes. To convert number fractions to mass fractions, we multiply by A

armi.nucDirectory.nucDir.getMc2Label(name)

Return a MC2 prefix label without a xstype suffix

MC**2 has labels and library names. The labels are like U235IA, ZIRCFB, etc. and the library names are references to specific data sets on the MC**2 libraries (e.g. U-2355, etc.)

This method returns the labels without the xstype suffixes (IA, FB). Rather than maintaining a lookup table, this simply converts the ARMI nuclide names to MC**2 names.

Parameters

name (str) – ARMI nuclide name of the nuclide

Returns

mc2LibLabel – The MC**2 prefix for this nuclide.

Return type

str

Examples

>>> nucDir.getMc2Label('U235')
'U235'
>> nucDir.getMc2Label('FE')
'FE'
>>> nucDir.getMc2Label('IRON')
'FE'
>>> nucDir.getMc2Label('AM242')
A242

armi.nucDirectory.nucDir.getMc2LibName(name)

returns a MC2 library name given an ARMI nuclide name

These are all 6 characters ‘U-2355’, ‘ZR S’, etc.

Parameters

name (str) – ARMI nuclide name of the nuclide

Returns

mc2LibLabel – The 6-character MC**2 library ID for this nuclide

Return type

str

See also

readMc2Nuclides()

reads a data file containing all the mc2 labels and chooses the proper library extension for each.

armi.nucDirectory.nucDir.getRebusLabel(name)

Return a REBUS label for the rebus input file.

This should have no intermediate spaces and should be 5 characters long Examples: “U235 “, “B10 “, etc.

Technically, this should be in the rebusInterface. No need to put specifics in this general module.

Parameters

name (str) – ARMI nuclide name like U235, B10, ZR, CU, etc.

armi.nucDirectory.nucDir.getMc2LabelFromRebusLabel(rebusLabel)

armi.nucDirectory.nucDir.getRebusLabelFromMc2Label(mc2Label)

armi.nucDirectory.nucDir.getElementName(z=None, symbol=None)

Returns element name

Parameters

• z (int) – Atomic number

• symbol (str) – Element abbreviation e.g. ‘Zr’

Examples

>>> nucDir.getElementName(10)
'Neon'
>>> nucDir.getElementName(symbol='Zr')
'Neon'

armi.nucDirectory.nucDir.getElementSymbol(z=None, name=None)

Returns element abbreviation given atomic number Z

Parameters

• z (int) – Atomic number

• name (str) – Element name E.g. Zirconium

Examples

>>> nucDir.getElementSymbol(10)
'Ne'
>>> nucDir.getElementSymbol(name='Neon')
'Ne'

armi.nucDirectory.nucDir.getNuclide(nucName)

Looks up the ARMI nuclide object that has this name

Parameters

nucName (str) – A nuclide name like U-235 or AM241, AM242M, AM242M

Returns

nuc – An armi nuclide object.

Return type

Nuclide

armi.nucDirectory.nucDir.getNuclides(nucName=None, elementSymbol=None)

returns a list of nuclide names in a particular nuclide or element

If no arguments, returns all nuclideBases in the directory

Used to convert things to DB name, to adjustNuclides, etc.

Parameters

• nucName (str) – ARMI nuclide label

• elementSymbol (str) – Element symbol e.g. ‘Zr’

armi.nucDirectory.nucDir.getNuclideNames(nucName=None, elementSymbol=None)

returns a list of nuclide names in a particular nuclide or element

If no arguments, returns all nuclideBases in the directory.

Warning

You will get both isotopes and NaturalNuclideBases for each element.

Parameters

• nucName (str) – ARMI nuclide label

• elementSymbol (str) – Element symbol e.g. ‘Zr’

armi.nucDirectory.nucDir.getAtomicWeight(lab=None, z=None, a=None)

returns atomic weight in g/mole

Parameters

• lab (str, optional) – nuclide label, like U235

• z (int, optional) – atomic number

• a (int, optional) – mass number

Returns

aMass – Atomic weight in grams /mole from NIST, or just mass number if not in library (U239 gives 239)

Return type

float

Examples

>>> from armi.nucDirectory import nucDir
>>> nucDir.getAtomicWeight('U235')
235.0439299

>>> nucDir.getAtomicWeight('U239')
239

>>> nucDir.getAtomicWeight('U238')
238.0507882

>>> nucDir.getAtomicWeight(z=94,a=239)
239.0521634

armi.nucDirectory.nucDir.getRebusNameFromMC2(mc2LibLabel=None, mc2Label=None)

maps an MC2 label to a rebus label

Parameters

• mc2LibLabel (str) – THe library ID on the MC**2 binary file (e.g. U-235S)

• mc2Label (str) – The mc**2 prefix to look up (e.g. U235)

armi.nucDirectory.nucDir.getNameFromMC2(mc2LibLabel=None, mc2Label=None)

maps an MC2 label to an ARMI label

Tries to maintain some backwards compatibility with old ISOTXS libs with B-10AA, CARBAA, etc.

Parameters

• mc2LibLabel (str) – THe library ID on the MC**2 binary file (e.g. U-235S)

• mc2Label (str) – The mc**2 prefix to look up (e.g. U235)

armi.nucDirectory.nucDir.getStructuralElements()

return list of element symbol in structure

armi.nucDirectory.nucDir.isHeavyMetal(name)

armi.nucDirectory.nucDir.isFissile(name)

armi.nucDirectory.nucDir.getThresholdDisplacementEnergy(nuc)

return the Lindhard cutoff; the energy required to displace an atom

From SPECTER.pdf Table II Greenwood, “SPECTER: Neutron Damage Calculations for Materials Irradiations”, ANL.FPP/TM-197, Argonne National Lab., (1985).

Parameters

nuc (str) – nuclide name

Returns

Ed – The cutoff energy in eV

Return type

float