1. n. [Formation Evaluation]

Phenomena involving the transfer of energy from neutrons to nuclei. The reaction rate of neutrons with matter depends on the density of neutrons, their velocity, the nuclear density and the particular interaction cross section. There are four principal neutron interactions that affect formation evaluation: elastic neutron scattering, inelastic neutron scattering, fast-neutron reactions and neutron capture.

See: chemical neutron source,  elastic neutron scattering,  fast-neutron reaction,  inelastic neutron scattering,  neutron capture,  neutron generator