Two-neutron and two-proton separation energies

4.2. Two-neutron and two-proton separation energies#

In this tutorial, you will learn how to obtain the two-neutron and two-proton separation energies from the experimental nuclear chart.

Import the libraries that will be employed in this tutorial.

# Import numpy
import numpy as np
# Import matplotlib
import matplotlib.pyplot as plt
# Import nucleardatapy package
import nucleardatapy as nuda

You can simply print out the properties of the nuda’s function that we will use:

# Explore the nucleardatapy module to find the correct attribute
print(dir(nuda.nuc.setupBEExp))

['D3n', 'D3p', 'S2n', 'S2p', '__class__', '__delattr__', '__dict__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__getstate__', '__gt__', '__hash__', '__init__', '__init_subclass__', '__le__', '__lt__', '__module__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '__weakref__', 'isotones', 'isotopes', 'print_outputs', 'select', 'select_year']

Get the full list of tables:

tables, tables_lower = nuda.nuc.be_exp_tables()
print('tables:',tables)

tables: ['AME']

Get the versions associated to this table:

versions, versions_lower = nuda.nuc.be_exp_versions(table = 'AME')
print('versions:',versions)

versions: ['2020', '2016', '2012']

Extract data from a given table and version:

mas_exp = nuda.nuc.setupBEExp( table = 'AME', version = '2020' )
print('number of nuclei:',mas_exp.nbNuc)

Oldest discovery is from:  1896
Most recent discovery is from:  2020
dist: [  20.   19.  118.  170.  253.  620.  510.  888.  632.  394.  310.  252.
   72. 1569.    0.    0.    0.    0.    0.    0.]
number of nuclei: 5827

Compute the two-neutron separation energies:

Zref = 50
mas_exp2 = mas_exp.select( state = 'gs', interp = 'n' )
mas_exp3 = mas_exp2.isotopes( Zref = Zref )
s2n = mas_exp3.S2n( Zref = Zref )

number of nuclei(Tot): 5573
number of nuclei(Sta): 2297
number of nuclei(Sel): 2297
Nmin,Nmax: 50 85

Compute the two-proton separation energies:

Nref = 50
mas_exp2 = mas_exp.select( state = 'gs', interp = 'n' )
mas_exp3 = mas_exp2.isotones( Nref = Nref )
s2p = mas_exp3.S2p( Nref = Nref )

number of nuclei(Tot): 5573
number of nuclei(Sta): 2297
number of nuclei(Sel): 2297
Zmin,Zmax: 29 50

print results:

print('N(Z=50):',s2n.S2n_N)
print('S2n(Z=50):',s2n.S2n)
print()
print('Z(N=50):',s2p.S2p_Z)
print('S2p(N=50):',s2p.S2p)

N(Z=50): [52 54 56 57 58 59 60 61 63 73 75 77 78 79 80 81 82 83 84 85]
S2n(Z=50): <bound method setupBEExp.S2n of <nucleardatapy.nuc.setup_be_exp.setupBEExp object at 0x7fb43cdca900>>

Z(N=50): [31 33 35 37 43 45 47]
S2p(N=50): <bound method setupBEExp.S2p of <nucleardatapy.nuc.setup_be_exp.setupBEExp object at 0x7fb43cdca900>>

Plot:

nuda.fig.nuc_setupBEExp_S2n_fig( None, tables, versions, Zref = 50 )

Plot name: None
Tables: ['AME']
Zref: 50
Oldest discovery is from:  1896
Most recent discovery is from:  2020
dist: [  20.   19.  118.  170.  253.  620.  510.  888.  632.  394.  310.  252.
   72. 1569.    0.    0.    0.    0.    0.    0.]
number of nuclei(Tot): 5573
number of nuclei(Sta): 2297
number of nuclei(Sel): 2297
Nmin,Nmax: 50 85

nuda.fig.nuc_setupBEExp_S2p_fig( None, tables, versions, Nref = 50 )

Plot name: None
Tables: ['AME']
Nref: 50

Oldest discovery is from:  1896
Most recent discovery is from:  2020
dist: [  20.   19.  118.  170.  253.  620.  510.  888.  632.  394.  310.  252.
   72. 1569.    0.    0.    0.    0.    0.    0.]
number of nuclei(Tot): 5573
number of nuclei(Sta): 2297
number of nuclei(Sel): 2297
Zmin,Zmax: 29 50