Artificial neural network (ANN) is applied to predict the number of produced neutrons from IR-IECF device in wide discharge current and voltage ranges. Experimentally, discharge current from 20 to 100？mA had been tuned by deuterium gas pressure and cathode voltage had been changed from ？20 to ？82？kV (maximum voltage of the used supply). The maximum neutron production rate (NPR) of 1.46 × 107？n/s had occurred when the voltage was ？82？kV and the discharge current was 48？mA. The back-propagation algorithm is used for training of the proposed multilayer perceptron (MLP) neural network structure. The obtained results show that the proposed ANN model has achieved good agreement with the experimental data. Results show that NPR of 1.855 × 108？n/s can be achieved in voltage and current of 125？kV and 45？mA, respectively. This prediction shows 52% increment in maximum voltage of power supply. Also, the optimum discharge current can increase 1270% NPR. 1. Introduction Inertial electrostatic confinement fusion (IECF) device is a compact and simple structure for nuclear fusion researches by electrical discharge, which can operate in the pulsed or continuous mode. It consists of two concentric (or coaxial) electrodes in which usually the central one (cathode) is negatively high-voltage-biased and the outward electrode (anode) is grounded. In this configuration, strong electric fields between electrodes lead to iodinating the filling gas and then accelerate the created ions toward the center, where the electrons are placed in the opposite direction. As a result, rather hot and dense plasma is formed in the center of cathode. In this situation, the continuous nuclear fusion reactions occur, which are the results of the beam-target and beam-beam interactions depending on the working conditions, although the beam-beam interactions will be negligible compared to beam-target reactions in the plasma conditions in this study. Therefore IECF is considered as a source of hot and dense plasma, highly energetic ions, and fast neutrons (when using deuterium or mixture of deuterium-tritium gas). IECF device is an excellent apparatus because of its ability to generate fast neutrons with high-flux from a small source for many applications, such as medicine (e.g., boron neutron capture cancer therapy) [1–3], radiography or tomography of thick materials, space propulsion system [4], inspection system and explosive landmine detection [5], neutron activation analysis, mine and petroleum exploration, and security screening. Therefore neutron production rate optimization in this device
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