PICsar: A 2.5D Axisymmetric, Relativistic, Electromagnetic, Particle in Cell Code with a Radiation Absorbing Boundary

TL;DR

PICsar is a new relativistic electromagnetic Particle in Cell code designed for efficient, axisymmetric simulations of magnetospheres, featuring boundary conditions and particle injection methods, validated through tests and capable of large-scale parallel computation.

Contribution

It introduces PICsar, a specialized 2.5D relativistic PIC code with boundary and coordinate innovations for simulating aligned rotator magnetospheres.

Findings

Accurately simulates aligned monopole rotator magnetosphere.

Efficiently maintains steady states from transients.

Scales well to many processors.

Abstract

We present PICsar -- a new Particle in Cell code geared towards efficiently simulating the magnetosphere of the aligned rotator. PICsar is a special relativistic, electromagnetic, charge conservative code that can be used to simulate arbitrary electromagnetics problems in axisymmetry. It features stretchable body-fitted coordinates that follow the surface of a sphere, simplifying the application of boundary conditions in the case of the aligned rotator; a radiation absorbing outer boundary, which allows a steady state to be set up dynamically and maintained indefinitely from transient initial conditions; and algorithms for injection of charged particles into the simulation domain. The code is parallelized using MPI and scales well to a large number of processors. We discuss the numerical methods used in PICsar and present tests of the code. In particular, we show that PICsar can accurately and efficiently simulate the magnetosphere of the aligned monopole rotator in the force free limit. We present simulations of the aligned dipole rotator in a forthcoming paper.