pynucastro.nucdata package

Properties of nuclei needed in construction reaction rates (in particular, the binding energies)

Submodules

pynucastro.nucdata.binding_table module

Reads tabular binding energy/nucleon data file and supplies table data.

class pynucastro.nucdata.binding_table.BindingTable(datfile=None)[source]

Bases: object

A simple class to manage reading and parsing the table of binding energy/nucleon.

get_binding_energy(n, z)[source]

Returns the binding energy given n and z.

header_length = 2
read()[source]

Read the binding energy table

pynucastro.nucdata.elements module

class pynucastro.nucdata.elements.Element(abbreviation, name, Z)[source]

Bases: object

class pynucastro.nucdata.elements.PeriodicTable[source]

Bases: object

classmethod lookup_Z(Z)[source]
classmethod lookup_abbreviation(abbrev)[source]
table = {'ac': <pynucastro.nucdata.elements.Element object>, 'ag': <pynucastro.nucdata.elements.Element object>, 'al': <pynucastro.nucdata.elements.Element object>, 'am': <pynucastro.nucdata.elements.Element object>, 'ar': <pynucastro.nucdata.elements.Element object>, 'as': <pynucastro.nucdata.elements.Element object>, 'at': <pynucastro.nucdata.elements.Element object>, 'au': <pynucastro.nucdata.elements.Element object>, 'b': <pynucastro.nucdata.elements.Element object>, 'ba': <pynucastro.nucdata.elements.Element object>, 'be': <pynucastro.nucdata.elements.Element object>, 'bh': <pynucastro.nucdata.elements.Element object>, 'bi': <pynucastro.nucdata.elements.Element object>, 'bk': <pynucastro.nucdata.elements.Element object>, 'br': <pynucastro.nucdata.elements.Element object>, 'c': <pynucastro.nucdata.elements.Element object>, 'ca': <pynucastro.nucdata.elements.Element object>, 'cd': <pynucastro.nucdata.elements.Element object>, 'ce': <pynucastro.nucdata.elements.Element object>, 'cf': <pynucastro.nucdata.elements.Element object>, 'cl': <pynucastro.nucdata.elements.Element object>, 'cm': <pynucastro.nucdata.elements.Element object>, 'cn': <pynucastro.nucdata.elements.Element object>, 'co': <pynucastro.nucdata.elements.Element object>, 'cr': <pynucastro.nucdata.elements.Element object>, 'cs': <pynucastro.nucdata.elements.Element object>, 'cu': <pynucastro.nucdata.elements.Element object>, 'db': <pynucastro.nucdata.elements.Element object>, 'ds': <pynucastro.nucdata.elements.Element object>, 'dy': <pynucastro.nucdata.elements.Element object>, 'er': <pynucastro.nucdata.elements.Element object>, 'es': <pynucastro.nucdata.elements.Element object>, 'eu': <pynucastro.nucdata.elements.Element object>, 'f': <pynucastro.nucdata.elements.Element object>, 'fe': <pynucastro.nucdata.elements.Element object>, 'fl': <pynucastro.nucdata.elements.Element object>, 'fm': <pynucastro.nucdata.elements.Element object>, 'fr': <pynucastro.nucdata.elements.Element object>, 'ga': <pynucastro.nucdata.elements.Element object>, 'gd': <pynucastro.nucdata.elements.Element object>, 'ge': <pynucastro.nucdata.elements.Element object>, 'h': <pynucastro.nucdata.elements.Element object>, 'he': <pynucastro.nucdata.elements.Element object>, 'hf': <pynucastro.nucdata.elements.Element object>, 'hg': <pynucastro.nucdata.elements.Element object>, 'ho': <pynucastro.nucdata.elements.Element object>, 'hs': <pynucastro.nucdata.elements.Element object>, 'i': <pynucastro.nucdata.elements.Element object>, 'in': <pynucastro.nucdata.elements.Element object>, 'ir': <pynucastro.nucdata.elements.Element object>, 'k': <pynucastro.nucdata.elements.Element object>, 'kr': <pynucastro.nucdata.elements.Element object>, 'la': <pynucastro.nucdata.elements.Element object>, 'li': <pynucastro.nucdata.elements.Element object>, 'lr': <pynucastro.nucdata.elements.Element object>, 'lu': <pynucastro.nucdata.elements.Element object>, 'lv': <pynucastro.nucdata.elements.Element object>, 'mc': <pynucastro.nucdata.elements.Element object>, 'md': <pynucastro.nucdata.elements.Element object>, 'mg': <pynucastro.nucdata.elements.Element object>, 'mn': <pynucastro.nucdata.elements.Element object>, 'mo': <pynucastro.nucdata.elements.Element object>, 'mt': <pynucastro.nucdata.elements.Element object>, 'n': <pynucastro.nucdata.elements.Element object>, 'na': <pynucastro.nucdata.elements.Element object>, 'nb': <pynucastro.nucdata.elements.Element object>, 'nd': <pynucastro.nucdata.elements.Element object>, 'ne': <pynucastro.nucdata.elements.Element object>, 'nh': <pynucastro.nucdata.elements.Element object>, 'ni': <pynucastro.nucdata.elements.Element object>, 'no': <pynucastro.nucdata.elements.Element object>, 'np': <pynucastro.nucdata.elements.Element object>, 'o': <pynucastro.nucdata.elements.Element object>, 'og': <pynucastro.nucdata.elements.Element object>, 'os': <pynucastro.nucdata.elements.Element object>, 'p': <pynucastro.nucdata.elements.Element object>, 'pa': <pynucastro.nucdata.elements.Element object>, 'pb': <pynucastro.nucdata.elements.Element object>, 'pd': <pynucastro.nucdata.elements.Element object>, 'pm': <pynucastro.nucdata.elements.Element object>, 'po': <pynucastro.nucdata.elements.Element object>, 'pr': <pynucastro.nucdata.elements.Element object>, 'pt': <pynucastro.nucdata.elements.Element object>, 'pu': <pynucastro.nucdata.elements.Element object>, 'ra': <pynucastro.nucdata.elements.Element object>, 'rb': <pynucastro.nucdata.elements.Element object>, 're': <pynucastro.nucdata.elements.Element object>, 'rf': <pynucastro.nucdata.elements.Element object>, 'rg': <pynucastro.nucdata.elements.Element object>, 'rh': <pynucastro.nucdata.elements.Element object>, 'rn': <pynucastro.nucdata.elements.Element object>, 'ru': <pynucastro.nucdata.elements.Element object>, 's': <pynucastro.nucdata.elements.Element object>, 'sb': <pynucastro.nucdata.elements.Element object>, 'sc': <pynucastro.nucdata.elements.Element object>, 'se': <pynucastro.nucdata.elements.Element object>, 'sg': <pynucastro.nucdata.elements.Element object>, 'si': <pynucastro.nucdata.elements.Element object>, 'sm': <pynucastro.nucdata.elements.Element object>, 'sn': <pynucastro.nucdata.elements.Element object>, 'sr': <pynucastro.nucdata.elements.Element object>, 'ta': <pynucastro.nucdata.elements.Element object>, 'tb': <pynucastro.nucdata.elements.Element object>, 'tc': <pynucastro.nucdata.elements.Element object>, 'te': <pynucastro.nucdata.elements.Element object>, 'th': <pynucastro.nucdata.elements.Element object>, 'ti': <pynucastro.nucdata.elements.Element object>, 'tl': <pynucastro.nucdata.elements.Element object>, 'tm': <pynucastro.nucdata.elements.Element object>, 'ts': <pynucastro.nucdata.elements.Element object>, 'u': <pynucastro.nucdata.elements.Element object>, 'v': <pynucastro.nucdata.elements.Element object>, 'w': <pynucastro.nucdata.elements.Element object>, 'xe': <pynucastro.nucdata.elements.Element object>, 'y': <pynucastro.nucdata.elements.Element object>, 'yb': <pynucastro.nucdata.elements.Element object>, 'zn': <pynucastro.nucdata.elements.Element object>, 'zr': <pynucastro.nucdata.elements.Element object>}
exception pynucastro.nucdata.elements.UnidentifiedElement[source]

Bases: Exception

pynucastro.nucdata.mass_table module

class pynucastro.nucdata.mass_table.MassTable(filename=None)[source]

Bases: object

The purpose of this class is to:

  1. Create a dictionary mapping nuclides to their mass excess A_nuc - A measured in MeV from the table mass_excess2020.txt.

  2. Parse the information of the previously defined dictionary to the Nucleus class.

The only required variable to construct an instance of this class is : var filename: that contains the .txt table file with the nuclei and their mass excess. If this variable is not provided, then mass_excess2020.txt is considered by default.

get_mass_diff(a, z)[source]

pynucastro.nucdata.nucleus module

Classes and methods to interface with files storing rate data.

class pynucastro.nucdata.nucleus.Nucleus(name, dummy=False)[source]

Bases: object

a nucleus that participates in a reaction – we store it in a class to hold its properties, define a sorting, and give it a pretty printing string.

Variables:

  • Z – atomic number

  • N – neutron number

  • A – atomic mass

  • nucbind – nuclear binding energy (MeV / nucleon)

  • short_spec_name – nucleus abbreviation (e.g. “he4”)

  • caps_name – capitalized short species name (e.g. “He4”)

  • el – element name (e.g. “he”)

  • pretty – LaTeX formatted version of the nucleus name

  • A_nuc – Nuclear Mass in amu

c()[source]

return the capitalized-style name

classmethod cast(obj)[source]
classmethod cast_list(lst, *, allow_None=False, allow_single=False)[source]
cindex()[source]

return the name for C++ indexing

classmethod from_cache(name, dummy=False)[source]
exception pynucastro.nucdata.nucleus.UnsupportedNucleus[source]

Bases: Exception

pynucastro.nucdata.nucleus.get_nuclei_in_range(zmin, zmax, amin, amax)[source]

given a range of Z = [zmin, zmax], and A = [amin, amax], return a list of Nucleus objects for all nuclei in this range

pynucastro.nucdata.partition_function module

class pynucastro.nucdata.partition_function.PartitionFunction(nucleus, name, temperature, partition_function, interpolant_order=3)[source]

Bases: object

This class holds the tabulated data for the partition function for a specific nucleus, which can be combined with other (non-overlapping) partition functions by addition and evaluated for different temperature values.

Adding two PartitionFunction objects is implemented by simply appending the temperature and partition function arrays of the higher-temperature partition function to those of the lower-temperature partition function. If the temperature ranges overlap, however, an exception is generated.

If either of the PartitionFunction objects added have already had a spline interpolant constructed, then construct a new spline interpolant for the returned PartitionFunction of order equal to the maximum order of the added PartitionFunction objects.

Variables:

  • nucleus – a string composed by a lowercase element and the atomic number, e.g. "ni56"

  • name – the name of the table on which the nucleus is read

  • temperature – a sorted array of all the temperatures involved

  • partition_function – an array with all the partition function values given in the same order as temperature

  • interpolant_order – the interpolation spline order, must be between 1 and 5, inclusive

construct_spline_interpolant(order=3)[source]

Construct an interpolating univariate spline of order >= 1 and order <= 5 using the scipy InterpolatedUnivariateSpline implementation.

Interpolate in log space for the partition function and in GK for temperature.

eval(T)[source]

Return the interpolated partition function value for the temperature T.

lower_partition()[source]

Return the partition function value for lower_temperature().

lower_temperature()[source]

Return the lowest temperature this object supports.

upper_partition()[source]

Return the partition function value for upper_temperature().

upper_temperature()[source]

Return the highest temperature this object supports.

class pynucastro.nucdata.partition_function.PartitionFunctionCollection(use_high_temperatures=True, use_set='frdm')[source]

Bases: object

This class holds a collection of PartitionFunctionTable objects in a dictionary keyed by the name of the tables.

In our discussion we have two different sets of tables: FRDM and ETFSI-Q.

Variables:

  • use_high_temperatures – whether to incorporate the high-temperature data tables

  • use_set – selects between the FRDM ('frdm') and ETFSI-Q ('etfsiq') data sets.

get_nuclei()[source]

Return a set of all the nuclei this collection supports.

get_partition_function(nuc)[source]

Return the PartitionFunction object for a specific nucleus.

class pynucastro.nucdata.partition_function.PartitionFunctionTable(file_name)[source]

Bases: object

Class for reading a partition function table file. A PartitionFunction object is constructed for each nucleus and stored in a dictionary keyed by the lowercase nucleus name in the form e.g. “ni56”. The table files are stored in the PartitionFunction subdirectory.

Variables:

  • name – the name of the table (as defined in the data file)

  • temperatures – an array of temperature values

get_nuclei()[source]

Return a set of the nuclei this table supports.

get_partition_function(nuc)[source]

Return the PartitionFunction object for a specific nucleus.

pynucastro.nucdata.spin_table module

class pynucastro.nucdata.spin_table.SpinTable(datafile=None, reliable=False)[source]

Bases: object

This class stores the nubase2020_1.txt table information in a dictionary data structure that maps nuclides to their number of nuclear spin states. Therefore, after setting an SpinTable class in rates.py, we can retrieve the spin states for a designated Nucleus class.

The variable reliable switch between using all the values of the tables, excluding the nuclei where only intervals are given and the values measured by strong experimental arguments.

get_spin_states(a, z)[source]