An implicit, conservative and asymptotic-preserving electrostatic particle-in-cell algorithm for arbitrarily magnetized plasmas in uniform magnetic fields

We introduce a new electrostatic particle-in-cell algorithm capable of using large timesteps compared to particle gyro-period under uniform external magnetic field. The extends earlier fully implicit PIC implementations with asymptotic-preserving particle-push scheme that allows much larger than gyroperiods. In the large-timestep limit, integrator preserves all drifts, while recovering full orbit for small timesteps. seamless, efficient treatment particles coexisting magnetized and unmagnetized species, conserves energy charge exactly without spoiling solver performance. demonstrate by numerical experiment several problems variable species magnetization (diocotron instability, modified two-stream drift instability) orders magnitude wall-clock-time speedups vs. standard are possible sacrificing solution accuracy.