Fully kinetic PiC simulations of current sheet instabilities for the solar corona

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In the Solar corona, magnetic energy is released through current sheets, transforming into particle and plasma energy via magnetic reconnection. The collisionless nature of coronal plasma indicates that these processes are primarily kinetic, best described by Particle-in-Cell (PiC) numerical simulations. Given the dominance of magnetic fields in the coronal plasma, it is crucial to consider large guide magnetic fields, differing from previous kinetic simulations of current sheets. Our goal is to identify and describe the key kinetic instabilities, turbulent processes, and anomalous transport effects. We begin by analyzing the case of zero guide field (antiparallel configuration) and identify several instabilities driven by temperature anisotropy that inhibit the tearing mode. These instabilities may arise numerically when more realistic parameters, such as high mass ratios, are applied in PiC simulations. We find that numerical temperature anisotropy can be effectively mitigated through higher-order shape functions. For current sheets with small guide fields, we present evidence of non-collisional resistivity in the generalized Ohm’s law. In scenarios with infinite guide fields, we compare our kinetic simulation outcomes with gyrokinetic theory, noting agreement in certain metrics like reconnection rates. However, magnetic field generation occurs only in PiC simulations with finite guide fields, attributed to initial shear flo