Calibration of Neutron Diagnostics for a Pulsed Fusion Device

Helion Energy is a fusion energy company pursuing commercial fusion systems based on a pulsed field reversed configurations of deuterium (D) and helium-3. Neutron diagnostics are essential tools for measuring the deuterium-deuterium (DD) neutron yield, which can be combined with other plasma diagnostics to estimate the total fusion yield. This work discusses calibration measurements taken during a joint campaign by Helion Energy with Lawrence Livermore National Laboratory using the Nevada National Security Site Gemini DD dense plasma focus (DPF). The neutron diagnostics used in this calibration include two LaBr$_3$:Ce detectors, two organic liquid scintillator detectors, a silver-based activation detector, and two beryllium-based activation detectors. The DPF was operated with total neutron yields in the range of 2.5x$10^{10}$ to 5.8x$10^{11}$ neutrons/pulse. Detectors were placed at multiple distances from the DPF giving a wide range of neutron fluences for the range of measurements taken. Results from this work will be used to further develop a full nuetron diagnostic suite for pulsed fusion devices at Helion.