I'm trying to write a stochastic simulation of a chain fission reaction in an enriched uranium sample (I plan to vary the concentration of U235 - from what I've read 4%U235 vs 96%U238 is what is used in commercial reactors). from my basic understanding of the process, a neutron is fired into the sample, where it is captured by a U235 atom which undergoes fission into two lighter elements and some stray neutrons. These stray neutrons go on to propogate the reaction. If not enough are released then the reaction will fizzle, if too many are produced you get a runaway reaction (as in the A-bomb). My question is: where can I find the laws that govern a) how many neutrons are emitted b) how much kinetic energy will they have when they are ejected. part b is relevant to my simulation because if the neutrons are too energetic, they won't be captured by a U235 atom and thus won't serve to propogate the reaction.