1.1.4.2 Neutron life The average time from the emission of a fission or prompt neutron to its absorption or escape is referred to as the prompt neutron lifetime, lp. It is usually approximated by the mean diffusion time, td, as shown in Eq. (1.41). The prompt neutron lifetimes strongly...
measurements which obtain the reactivity as a function of time after a rod or reactor component is removed from a delayed critical assembly, and (4) prompt neutron decay constant measurements from which the reactivity can be obtained if corrections are made for changes in the neutron lifetime. ...