Coupled MHD-PIC framework for magnetic reconnection

Magnetic reconnection in the solar atmosphere is still not a properly understood phenomenon. The effects of the magnetic field on the particles is on such small scales that the requirements for MHD are no longer fulfilled and we need another description. In this study we introduce a new numerical framework capable of simulating a large scale MHD experiment with subregions utilising a Particle-in-cell (PIC) model. These two domains are coupled, so the PIC boundary values are determined from the MHD domain, while the results of the particle effects inside the PIC domain will be felt out through the MHD domain. This model allows us to examine the small scale particle effects occurring during magnetic reconnection without sacrificing the connection to the larger scale behaviour.