A simple neutron source
Getting at the neutrons in a nucleus
Neutrons are part of the nucleus of an atom so if you want to get at them you have to knock them out. This was how the neutron was discovered.
The idea is that you 'shine' alpha particles from, say, an americium source at a target made of an element with small atoms, like beryllium.
In practice this may be as simple as powdering americium and beryllium and mixing them together.
Activity Use a neutron source to initiate chain reactions in bombs and a nuclear reactor.The nucleus is very difficult to hit
It takes tens of thousands of alphas for each neutron that gets knocked because the nucleus is so small compared with an atom.