On the Randomness of a Neutron’s Kinetic Energy as It Slows Down by Elastic Collisions in an Infinite Medium

The infinite-medium pure-scattering slowing down model was developed by Fermi and coworkers soon after the discovery of the neutron. The model, although highly idealized, still has conceptual value and is a useful thinking aid. Previous work on the model has been restricted to certain kinds of average behavior. We take a more detailed look at the random behavior of the neutron’s kinetic energy as it slows down.