REFLECTOR EFFECT ON NEUTRON WAVE PROPAGATION IN MULTIPLYING MEDIA.

Neutron waves in a reflected reactor are analyzed using the two-group diffusion equation. The solution is composed of a transient which disappears within a few milliseconds, a steady-state part, and an oscillatory part. The last is comprised of four terms corresponding to four waves: two propagating waves and two reflected waves. The amplitudes and phases of the four waves are calculated, together with those of the total wave which is the sum of the four partial waves. Modulated poison and source oscillators were used for the experiments.