ZURUECK HOCH VOR INHALT SUCHEN

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Proposing Institution

Max-Planck-Institute for Solar System Research
Project Manager

Prof. Dr. Joerg Buechner
Justus-von-Liebig-Weg 3
37077 Göttingen
Abstract
The hot and dilute collisionless plasmas near the Earth and in the solar-wind are very turbulent. Astrophysical plasmas, e.g., in accretion disks around stars, in the interstellar medium (ISM) or in galaxy clusters are expected to be turbulent as well. Despite of the omnipresence of turbulence in the plasma Universe, its properties and consequences are not well understood, yet. The reason is the complicated kinetic nature of the collective plasma phenomena at the end of the turbulence cascade in collisionless plasmas which has to be understood to solve outstanding astrophysical problems like the, release of magnetic energy by reconnection, the heating of stellar coronae and ISM. Of particular interest is the role of current sheets and reconnection in the turbulence. A kinetic description is required to solve these questions, including non-thermal effects, wave-particle interactions, nonlinearities and smallest spatial and shortest temporal scales of the turbulence. During the first phase of this project state-of-the-art 2D and 3D kinetic numerical simulations were carried out by self-consistently solving reduced and full sets of Vlasov- and Maxwell equations describing the interaction of electromagnetic fields and charged particles. Utilizing massively parallel running Vlasov-Hybrid and two different PIC- simulation codes the properties of the turbulence in the near-Earth, free streaming solar wind plasma were explored. Our simulations revealed new aspects of solar wind turbulence. It opened, however, new questions like the nature of the kinetic turbulence in the Earth's magnetosheath. Currently ongoing observations of the MMS space mission revealed its differences compared to the free streaming solar wind turbulence. Reasons to be explored are, presumably, the non-thermal features, temperature ratios and anisotropies of the plasma constituents. In order to investigate them we ask for a continuation of the project using our codes and diagnostic tools on the new computing facilities of SuperMUC at the LRZ.

Impressum, Conny Wendler