fast neutron

Quick Reference

A neutron resulting from nuclear fission that has an energy in excess of 0.1 MeV (1.6 × 10−14 J), having lost little of its energy by collision. In some contexts fast fission is defined as fission brought about by fast neutrons, i.e. neutrons having energies in excess of 1.5 MeV (2.4 × 10−13 J), the fission threshold of uranium–238. See also nuclear reactor; slow neutron.

Subjects: Physics.

Reference entries