Activation detection of the neutron yield from a DPF pulsed neutron source

Activation detection is used to measure the neutron yield from a DPF neutron source with narrow pulse width and high neutron flux. A method to shield the scattering neutrons was implemented to improve measurement resolution. Various calibration methods are discussed in detail, calibration curves and coefficients are obtained for three distances based on the method for stopping the radiation after the detector is saturated using an accelerator-type neutron source. Several physical calibration problems were analyzed, such as how the detector dead time affects the measurement range and how the two silver decay types affect the calibration results. The main measurement error was evaluated and a practical method was proposed to handle the effect of the scattering neutrons.