Dr. Chuwen Ma, Shanghai Jiao Tong University

An implicit asymptotic-preserving and energy-charge conserving (APECC) Particle-In-Cell method is proposed to solve the Vlasov-Maxwell (VM) equations in the quasi-neutral limit. Charge conservation is enforced by particle orbital averaging and fixed sub-time steps. The truncation error depending on the number of sub-time steps is further analyzed. The Crank-Nicolson method is used to exactly conserve the discrete energy. The key step in the asymptotic-preserving iteration for the nonlinear system is based on a decomposition of the current density in the Maxwell model from the Vlasov equation. Moreover, we show that the convergence is independent of the quasi-neutral limit. Using extensive numerical experiments, we show that the proposed method can achieve asymptotic preservation and energy-charge conservation.