Analytical Particle Pusher for Electrostatic PIC Models with Linear Electric Field Shear

Particle-in-Cell (PIC) is a widely adopted methodology that enables plasma simulations from first principles. Standard PIC codes usually use Boris-Buneman scheme to advance particles in the velocity phase space and leapfrog type method in the spatial phase space. However, due to the need to resolve the particle's gyromotion in the presence of a magnetic field, the time step required is often smaller than the CFL-type time scale. To tackle this problem, we propose an analytic particle pusher obtained by solving the Newton-Lorentz equation for a single particle in the presence of a uniform magnetic field and a linear gradient electric field at an arbitrary angle. This field configuration is motivated by the linear interpolation used during field gathering and charge deposition in a typical PIC scheme. Implementation of the analytic pusher in the hybrid plasma PIC code, hPIC2, will be presented using test particle problems and PIC simulation of a magnetized two-stream instability. Additionally, we compare the performance of the new pusher against the standard Boris-Buneman scheme.