Simulation and evaluation of γ signal detection from P-¹¹B reactions in EHL-2

The detection of γ signals is one of the most effective methods for verifying the p-11B reaction on the ENN He-Long 2 (EHL-2) spherical torus. This paper establishes a comprehensive γ detection and evaluation framework of p-11B reaction with Geant4, which can acquire the signals received by detectors according to various plasma parameters. We conducted parameter scans to simulate optimization of detector spatial configuration, optimal signal acquisition performance can be achieved. Meanwhile, the likelihood estimation method is adopted to evaluate the interference degree of background X-rays on characteristic γ signals. Using the design parameters of the EHL-2, the simulation results show that the optimal observation peak for verifying the reaction is the 4.4 MeV characteristic peak, which can be effectively observed when the signal-to-noise ratio (SNR) is higher than 0.012. The results provide a theoretical basis for optimizing the operational performance of the EHL-2, encompassing X-ray background suppression, plasma configuration, and discharge regime optimization.