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.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.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.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