Concurrent Measurement of Individual Gamma-Ray Spectra During and Between Fast Neutron Pulses

A fast commercial digital multi-channel analyzer (DMCA) with a 40 MHz sampling frequency, was modified for concurrent acquisition during the same data collection run, of two separate gamma-ray spectra induced during and between fast neutron pulses. The DMCA was programmed to monitor the incoming and observed count rates, and the resulting real times and dead times separately for each spectrum. We report here the performance of the DMCA in terms of it's monitoring capabilities for each channel when using a pulsed 14 MeV neutron generator. The losses in the incoming and observed count rates were modeled based on the basic dead time parameter of the system