An investigation of the simulation response of GEM-based detector for the fast neutrons by employment of GEANT4 & MCNP MC codes

Abstract

The current work explores the potential ability to identify fast neutrons with one Gas Electron multiplier (GEM) detector connected to a polyethylene (PE) converter. Hence, a simulation was tested utilizing the GEANT4 Monte Carlo and MCNP simulation codes. The GEM detector functions by detecting the charged particles generated by an (n, p) reaction on a polyethylene. Fast neutrons in the ranging with energy levels of 1.0 MeV to to 25 MeV have the ability to travel towards the detector surface and evaluation was conducted from its response. For the 1 mm, 2 mm and 3 mm converter thickness, the sensitivity remains ∼ 9.8% and 13.4%, and 14.2% respectively via GEANT4 QGSP_BERT_HP physics lists. For the same converter thicknesses, sensitivity remains ∼ 9% and 12%, and 12.5% using the QGSP_BIC_HP physics list. Using the MCNP, with a 1 mm, 2 mm and 3 mm converter thickness, the sensitivity remains ∼ 12.8%, 13.3% and 13.6% via cell-flux tally method, while with the MCNP pulse- height technique with the same converter thicknesses, the sensitivity remains ∼ 10.6%, 12% and 13.3% respectively. The current findings reveals that GEM detector exhibits a clear and efficient response to inserted fast neutrons. Consequently, GEM based detectors have a potential to be a better candidate for fast neutron detection.