iPIC3D: implicit Particle-in-Cell code for Space Weather Applications (KTH)
Space weather is the study of the processes originating in the sun and propagating through the solar system, with effects on people and technology in space and on the earth, ranging from auroras in the polar regions to electromagnetic disturbances causing disruptive currents in infrastructure such as power and communication lines. KTH has implemented the massively parallel Particle-in-Cell code, iPIC3D as a C++ program using MPI and OpenMP. It simulates the interaction between solar wind and the Earth magnetic field. Plasma particles from the solar wind are mimicked by computational particles. At each computational cycle, the velocity and location of each particle are updated, the current and charge density are interpolated to the mesh grid and Maxwell’s equations are solved. The magnetosphere is a large system with many complex physical processes, requiring realistic domain sizes and billions of computational particles. The use case for the AllScale project, plasma particles interacting with the Earth’s magnetic field, is depicted in the figure. Some highly energetic particles are trapped while others escape the confinement of the magnetic field. This leads to large load imbalances since particles concentrate close to the Earth while few particles are located in other regions of space. Within AllScale, we will carry out the very first PIC simulation of radiation belt formation enabling new science and new discoveries in the field of particle-wave interaction in the radiation belts. The iPIC3D code is used in production by several groups in European Universities, such as KU- Leuven and the University of Pisa, all of which will benefit from the AllScale results.