Radiation chart of nuclides

1. Nuclear Radiation
Chart of the Nuclides

2. Chart of the Nuclides
The Chart of the Nuclides is important to
understand because it is a common tool used in the
radiation industry
The Chart is similar to the periodic table in that it
lists all known elements, atomic #’s, atomic mass,
etc.
However, it also gives all the different known
isotopes for each element
The Chart is in reality a graph of all the known
nuclides graphing proton # vs. neutron #

4. Chart of the Nuclides
The row #’s are equivalent to the atomic
number of the element
Thus each row, represents a different
element
The column #’s are equivalent to the
neutron numbers of the nuclides

12. Chart of the Nuclides
The first box in each row is a label for that
row, it is not a nuclide
The information given in that box includes..
The chemical symbol & name of the element
The atomic mass of the element
The absorption cross section in the units of
Barns (s)
A Barn is a unit of area which is determined
by the diameter of the nucleus

14. Chart of the Nuclides
Stable nuclides are gray colored boxes, they
contain…
The chemical symbol of the element
The number of nucleons (Protons + Neutrons),
which equals the atomic mass
The % of abundance in nature
And the capture cross section in Barns (s)
The plot of all the stable nuclides, called the
line of stability, forms a linear plot ~ 45º

16. Chart of the Nuclides
Unstable nuclides are indicated by all the
other boxes shown on the chart
Each of those boxes contain…
The chemical symbol of the element
The number of nucleons, or atomic mass
The half-life of the nuclide
a – years, d – days, h – hours, m – minutes
s – seconds, ms – milliseconds, ms – microseconds
~ - approximately

17. Half-Life
•Half-life, t
1/2
, is the time required for half the atoms of
a radioactive nuclide to decay.
•Each radioactive nuclide has its own half-life.
•More-stable nuclides decay slowly and have longer
half-lives.

18. Click below to watch the Visual Concept.
Half-Life

20. Potassium-40 Half-Life

21. Rate of
Decay

22. Half-Lives of Some Radioactive Isotopes

23. Chart of the Nuclides
Mode of decay i.e. a - alpha, b - beta, It –
Isomeric Transition
Energy of decay, given in MeV
g - gamma emission, which is a result of decay
Gamma energies in KeV

25. Chart of the Nuclides
Another type of nuclide shown on the chart
are those that undergo isomeric decay
Isomeric decay results from a nuclide
giving off an alpha or beta and becoming a
metastable form
These atoms will give off energy like a
gamma when they de-excite at a later time
These are shown on the chart as a box
inside a box

27. Chart of the Nuclides
Some radioactive nuclides can undergo
what is called “branching” decay
This means that under some circumstances
they can give off one form of radiation, but
under other circumstances they give off
another
Example – Copper 64, gives off beta – or beta +
Both modes of decay will be given in the
box on the chart

30. Chart of the Nuclides
Using the Chart of the Nuclides we can
easily tell what a radioactive isotope
changes into after decay
By moving from box to box based on
whether or not protons or neutrons are lost
or gained as a result of radiation release, we
can determine the resulting isotope

37. Chart of the Nuclides
Using this information you can follow
radioactive decay until it reaches stability
In nature, there are three naturally occurring
decay chains
They each begin with nuclides that have
long enough half-lives that they have been
present since the formation of the Earth

39. Chart of the Nuclides
As the nuclides in the decay chains release
radiation, they change into other nuclides
that are also radioactive
They continue this process until they reach
a stable isotope (usually lead)
i.e. All of the Uranium 238 on the earth will
eventually become lead

41. Chart of the Nuclides
There is another decay chain that was
created with the beginnings of nuclear
energy (Man Made)
It is called “Transuranic Decay Chain” and
begins with the element Plutonium
This leads us into the two activities which
use the Chart of the Nuclides
Activity 1 & 2 pp 117 - 119