> A moderator on the other hand inelastically scatters neutrons,
Most moderators elastically scatter neutrons. What other kind of collision could there be with a hydrogen nucleus?
Most moderators elastically scatter neutrons. What other kind of collision could there be with a hydrogen nucleus?
THe neutron/nucleus collisions in a moderator are largely elastic. The total kinetic energy of the neutron and the nucleus is conserved, although kinetic energy is transfered from the neutron to the nucleus.
An inelastic collision would involve (for example) nuclear excitation of the target nucleus, or ejection of particles from the target nucleus. The neutrons from fission are usually too low in energy for this to be very likely, though.