Simulation study of a “fission electron-collection” neutron detector

•We present a full simulation of physical processes of detection for a FECND.•Giving the general properties of escaping electrons.•Confirming the impact of escaping fragments.•Giving a design to decrease the impact of incoming gamma flux.

This work studied a “fission electron-collection” neutron detector via the Monte Carlo method. The detector consists of two metal electrodes, labeled the coated and collection electrodes, mounted in a vacuum. The first electrode is coated with triuranium octoxide. The detector uses the “fission electron-collection” technique, which does not require an intermediate material and directly collects electrons from the coating. This detector can achieve rapid, flat-energy responses, which are important for measuring pulsed neutron sources. This paper presents the physical detection processes and Monte Carlo simulation studies using the Geant4 toolkit. The results indicate that the detector sensitivity is approximately 1.5 × 10−21 [C/(n/cm2)] and the FWHM of response function is 2.5 ns. Additionally, the escaping electrons are characterized, and the detector sensitivity is determined for various coating thicknesses.