which are flying around with very high amounts of energy, and especially high
neutron fluxes occur within supernovas, when these stars run out of fuel and
explode in spectacular fashions as we can actually observe with astronomy.
So with all these neutrons flying around with these high energies both
in modest amounts in normal star processes and
also in very high amounts in supernovae.
Let's explore the possibility of using these neutrons to
build the heavier elements.
This is a small section of the chart of the nuclides that I presented earlier.
In which you have neutrons along the X axis and protons along the Y axis.
This is a segment that presents the element silver, cadmium, indium,
tin and antimony.
And we are going to use these elements to explore what happens to nuclei in
stellar environments where they are bombarded by free neutrons.
If you take and add a neutron to silver, with a mass of 109.
And when I say mass, that means the number of neutrons and
protons combined together, then you, you hit that nuclei with a neutron.
That becomes mass-110, because you added another neutron, but
silver-110 is not stable.
And so it decays to cadmium-110.
You've just built cadmium-110, you hit cadmium-110 with a neutron and
you build 111.
You hit it with another neutron, 112, and so on.
Once you get over to the far end or the far right side of cadmium to 114,
and you build 115, 115 is not stable, and
115 will very rapidly decay to indium 115, and so you can
see by this process of just simply adding more and more neutrons to existing nuclei.
You go up the up the periodic table, or
up the chart of the nuclides in this case, to heavier and heavier elements, and
you get all the way up to uranium by this means.
But this does not explain the existence of isotopes
like cadmium 116, for example.