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

In the Solar corona, magnetic energy is conjectured to be released
through current sheets to be transformed to particle,
plasma energy and heating by magnetic reconnection. Since
the coronal plasma is collisionless, these are essentially kinetic
plasma processes. Their nonlinear physics and properties can
be described best by Particle-in-Cell (PiC) numerical simulations.
Since the coronal plasma is magnetically dominated, and in contrast
to previous kinetic simulations of current sheets, the presence
of large guide magnetic fields has to be taken into account.
We aim at finding and describing the resulting dominating kinetic
instabilities, turbulent processes and anomalous (collisionless)
transport effects.
In order to validate our methods, first we analyze the limit case
of zero guide field (antiparallel configuration). We find several instabilities
driven by temperature anisotropy inhibiting the tearing
mode. They might be numerically induced when more realistic
parameters (high mass ratios) are used in PiC simulations. This
numerical temperature anisotropy can be efficiently reduced by
using higher order shape functions. For current sheets in the
presence of small guide fields, we show evidence of non collisional
resistivity in the generalized Ohm's law. And in the limit
of infinite guide fields, we compare our kinetic simulation results
with gyrokinetic theory. Although there is agreement in some
quantities such as reconnection rates between both plasma models,
we find a magnetic field generation only in PiC simulations
with finite guide fields, due to an initial shear flow in the force free
current sheet initialization. In addition, we also find signatures of
cross-streaming instabilities producing anisotropic electron heating
and acceleration.