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Statistical analysis of ions in two-dimensional plasma turbulence

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 نشر من قبل Francesco Pecora
 تاريخ النشر 2019
  مجال البحث فيزياء
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 تأليف Francesco Pecora




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The statistical properties of ions in two-dimensional fully developed turbulence have been compared between two different numerical algorithms. In particular, we compare Hybrid Particle In Cell (hybrid PIC with fluid electrons) and full PIC simulations, focusing on particle diffusion and acceleration phenomena. To investigate several heliospheric plasma conditions, a series of numerical simulations has been performed by varying the plasma $beta$ - the ratio between kinetic and magnetic pressure. These numerical studies allow the exploration of different scenarios, going from the solar corona (low $beta$) to the solar wind ($beta sim 1$), as well as the Earths magnetosheath (high $beta$). It has been found that the two approaches compare pretty well, especially for the spectral properties of the magnetic field and the ion diffusion statistics. Small differences among the models have been found regarding the electric field behaviour at sub-ion scales and the acceleration statistics, due evidently to the more consistent treatment of the plasma in the full PIC approach.



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