Erlangen 2026 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

P: Fachverband Plasmaphysik

P 2: Astrophysical Plasmas

P 2.1: Vortrag

Montag, 16. März 2026, 14:45–15:10, KH 01.020

Astrophysical perpendicular shocks for intermediate Mach numbers — •Valentine Devos, Artem Bohdan, and Frank Jenko — Max Planck Institute for Plasma Physics, Garching bei München

This project investigates the microphysics and structure of collisionless shocks from planetary to astrophysical scales, focusing on the intermediate Mach-number regime. Using fully kinetic Particle-In-Cell simulations, we study the transition from low-Mach instabilities (whistler precursors, modified two-stream modes) to high-Mach regimes dominated by Weibel and Buneman instabilities.

A key objective is to characterise electron kinetics and the conditions enabling efficient acceleration through Diffusive Shock Acceleration (DSA), Shock Surfing (SSA), and Shock Drifting (SDA).

To identify and track instabilities, we compute theoretical whistler anisotropy thresholds from particle distributions, evaluate linear growth rates for whistler and Weibel modes, and compare them with simulation results. We also derive dispersion relations to link the observed wave activity to the underlying kinetic processes.

Overall, this work clarifies how micro-instabilities regulate electron heating and acceleration across Mach numbers, connecting low- and high-Mach collisionless shocks in space and astrophysical plasmas.

Keywords: Shocks; Whistler instability; Weibel instability; PIC simulations; Electron acceleration