Abstract

Pulsed source method is to determine the degree of a subcritical reactor method, practice, its applicability and the time characteristics of the pulse source related. Analytic method to derive the pulse waveform along the time after the source of the diagnosis of sub-critical system time constant neutron intrinsic values, and numerical calculations were verified with a clear diagnosis of a pulsed source neutron sub-critical system time constant required to meet the foreign conditions. The results show that, in the present study concerns the time scales, pulse diagnosis of the source law applicable to the target volume of external neutron source requirement is the time decay depth must be deeper than the degree of sub-critical device. The pulsed source method is one of the methods to confirm the time multiplication constant α eigenvalue for a subcritical reactor. Practically its applicability is determined by the characteristic of the neutron source. The analytic and numerical methods were both used to analyze the affect of the temporal characteristic of dense plasma focus source in the pulsed neutron method. The result indicates that the requirement of the temporal characteristic of dense plasma focus source in the pulsed neutron method is ultra fast and ultra short