3-D Simulation of Cavity SGEMP Interference Generated by Pulsed X-Rays

A 3-D electromagnetic particle-in-cell simulation code 3Dcavitysgemp V1.0 is developed to compute the cavity System-Generated Electromagnetic Pulse (SGEMP) interference generated by pulsed X-rays. Discrete charge conservation theorem, conformal mesh technique, and time-biased algorithm are introduced to improve the calculation accuracy. Based on a cylinder cavity model, the 3-D results are verified by previous 2-D simulation and demonstrate the special distributions and resonant frequencies of cavity SGEMP. The peak value of cavity SGEMP main pulse is 72.88 kV/m. When farther away from the charge-emitting face, the field strength becomes smaller quickly and its polarity reverses; when the distance from the symmetry axis increases, the field strength declines relatively slower. Moreover, it is proven that the cavity SGEMP would form a stable resonance and its frequency is dominated by the radius and length of the cavity.