MCNPX simulations of the silicon carbide semiconductor detector response to fast neutrons from D–T nuclear reaction

Abstract

Silicon Carbide (SiC) has been long recognized as a suitable semiconductor material for use in nuclear radiation detectors of high-energy charged particles, gamma rays, X-rays and neutrons. The nuclear interactions occurring in the semiconductor are complex and can be quantified using a Monte Carlo-based computer code. In this work, the MCNPX (Monte Carlo N-Particle eXtended) code was employed to support detector design and analysis. MCNPX is widely used to simulate interaction of radiation with matter and supports the transport of 34 particle types including heavy ions in broad energy ranges. The code also supports complex 3D geometries and both nuclear data tables and physics models. In our model, monoenergetic neutrons from D-T nuclear reaction were assumed as a source of fast neutrons. Their energy varied between 16 and 18.2 MeV, according to the accelerating voltage of the deuterons participating in D-T reaction. First, the simulations were used to calculate the optimum thickness of the reactive film composed of High Density PolyEthylene (HDPE), which converts neutral particles to charged particles and thusly enhancing detection efficiency. The dependency of the optimal thickness of the HDPE layer on the energy of Int. J. Mod. Phys. Conf. Ser. 2016.44. Downloaded from www.worldscientific.com by 158.106.208.226 on 09/01/18. Re-use and distribution is strictly not permitted, except for Open Access articles. K. Sedlačková et al.1660226-2 the incident neutrons has been shown for the inspected energy range. Further, from the energy deposited by secondary charged particles and recoiled ions, the detector response was modeled and the effect of the conversion layer on detector response was demonstrated. The results from the simulations were compared with experimental data obtained for a detector covered by a 600 and 1300 m thick conversion layer. Some limitations of the simulations using MCNPX code are also discussed.

Conversion of fast neutrons for neutron radiography with TPX2 detector

“…Some of the possible reactions are listed in Table1together with their calculated Q values. More reactions can be found elsewhere[18,19]. In the case of our experiment with 3.55 MeV neutrons, only the elastic scattering (n,n), radiative capture (n,) and (n,) nuclear reactions were possible.…”

Relative dose-response from solid-state and gel dosimeters through Monte Carlo simulations

“…Several Monte Carlobased codes are used in physics research [36][37][38][39][40][41]. The MCNPX code was developed to study particle physics and nuclear reactions, so they simulate an extensive set of particles in a broad energy spectrum [42][43][44][45] and many medical physics applications [46][47][48][49][50]. On the other hand, codes such as PENELOPE focus on the transport of charged particles and photons to medical applications and simulation of accelerator linear in the context of radiation protection and dosimetry [51][52][53][54][55].…”