Development of a Current-Readout Type Neutron Monitor for Burst Neutron Fields

*We report on the development of a current-readout type neutron monitor for the measurement of the dose rate of burst neutrons generated by beam loss in an accelerator that occurs within a short time span. This neutron monitor consists of a commercially available neutron proportional counter, a 6.5-cm thick polyethylene moderator, and a newly developed charge-integration circuit. The monitor was tested under mono-energetic neutron standard fields (En = 8 keV to 15 MeV) and was compared with a conventional pulse-readout type monitor. The energy response of the current-readout monitor is identical to that of the pulse-readout monitor. The current-readout monitor is able to measure neutron doses up to 4.5 mSv/h without count loss, whereas the pulse-readout monitor fails due to count loss.