Paralyzable and non-paralyzable dead-time corrections for the neutron detectors of the KUCA facility driven by external neutron sources

Abstract

ABSTRACT This study examines dead-time corrections for the neutron detectors of the Kyoto University Critical Assembly (KUCA) driven by a stationary or pulsed external neutron sources. For the stationary (californium) external neutron source, the MCNP simulations producing the detector timestamps and the MATLAB scripts correcting for the dead-time effect have been validated with analytical formulae from literature. For the pulsed external neutron source (produced by a proton accelerator), the experimental detector timestamps have been corrected for the dead-time effect using the aforementioned MATLAB scripts utilizing the backward extrapolation method and the paralyzable or non-paralyzable dead-time model. Then, the keff obtained from the dead-time corrected timestamps has been corrected for the detector position and type. Finally, the corrected experimental keff has been compared with the one obtained from MCNP criticality simulations.