2024/10/08 by K. M. Schoeffler, Björn Eichmann, Schoeffler, K. M. +5 · 1 citation
Engineering · Physics and Astronomy · #Dust and Plasma Wave Phenomena #FOS: Physical sciences #High-Energy Particle Collisions Research #Laser-induced spectroscopy and plasma #Plasma Physics (physics.plasm-ph)
paper · pdf · doi:10.48550/arxiv.2410.05619
openalex publication_date 2024/10/08 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Two-dimensional particle-in-cell (PIC) simulations explore the collisionless tearing instability developing in a Harris equilibrium configuration in a pair (electron-positron) plasma, with no guide field, for a range of parameters from non-relativistic to relativistic temperatures and drift velocities. Growth rates match predictions of Zelenyi & Krasnosel'skikh (1979) modified for relativistic drifts by Hoshino (2020) as long as the assumption holds that the thickness a of the current sheet is larger than the Larmor radius ρL, with the fastest growing mode at ka ≈ 1/√(3). Aside from confirming these predictions, we explore the transitions from thick to thin current sheets and from classical to relativistic temperatures. We show that for thinner current sheets (a< ρL), the growth rate matches the prediction for the case a=ρL. We also explore the nonlinear evolution of the modes. While the wave number with the fastest growth rate initially matches the prediction of Zelenyi & Krasnosel'skikh (1979), these modes saturate moving the dominant mode to lower wave numbers (especially for thick current sheets with low growth rates). Furthermore, at a late, non-linear stage, the growth rate (initially following the growth rate prediction proportional to (ρL/a)3/2 < 1) increases faster than exponentially, reaching a maximum growth rate equivalent to the linear growth rate prediction at ρL/a = 1, before eventually saturating.