how does one “obtain” neutrons to fire at atomic nuclei?

Question

so, i get that atoms can be split by colliding with neutrons, but how does one get a singular neutron?

In: 2

Answer 1

By grabbing radioactive stuff that is decaying and emitting particles in the process. Take your pick: electrons, neutrons, positrons, helium.. wathever you need.

You don’t need to “get” a singular neutron, you just need to bring that stuff close enough to your fissile material so that the neutrons hit your atoms and the chain reaction starts.