Ion-Neutral Elastic Scattering Cross Sections for Kinetic Plasma Simulations in Aleph

Collisions in a plasma can be very complex. Birdsall
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showed methods and models to merge Particle-in-Cell (PIC) with Monte Carlo Collisions (MCC). Importantly, he pointed out that more atomic physics models were needed to treat collisions. Advances in computing hardware and software now enable large scale simulations of physical (vs. spherical cow) systems. However, treatment of collisions is inherently computationally intensive and experimental scattering data for many collision pairs is scarce at best. Consequently, to treat collisions in plasma simulations, researchers are required to extrapolate from experimental scattering data or adopt empirical scattering models
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, for which the overall accuracy is largely unknown.