AI Insight
This study uses two-dimensional relativistic particle-in-cell (PIC) simulations to model magnetic reconnection in pair plasmas with multiple interacting current sheets, conditions relevant to high-energy astrophysical environments such as pulsar wind nebulae. The simulations reveal that an initial phase of isolated reconnection within each sheet accelerates particles and produces synchrotron emission exceeding the classical burn-off limit, after which plasmoid-driven cross-sheet interactions generate a Kolmogorov-like turbulent magnetic energy spectrum spanning roughly two decades, with a dissipation scale near 5 electron inertial lengths. The turbulent phase provides secondary particle acceleration and intermittent synchrotron bursts, though the high-energy particle distribution retains a steep spectral slope throughout.
Why it matters
Understanding how magnetic reconnection transitions into turbulence in relativistic pair plasmas helps explain observed high-energy radiation from astrophysical sources such as pulsar wind nebulae and relativistic jets. These findings may refine theoretical models used to interpret gamma-ray and X-ray observations from such environments.
arXiv:2605.19109v1 Announce Type: cross
Abstract: Two-dimensional relativistic particle-in-cell (PIC) simulations of radiative magnetic reconnection in pair plasmas with multiple interacting current sheets are carried out to mimic the dynamics in high-energy astrophysical environments, such as particle acceleration regions in pulsar wind nebulae and relativistic outflows, where the magnetic field is expected to reverse polarity multiple times. Initially, due to reconnection within each isolated sheet, particles are accelerated and synchrotron emission beyond the burn-off limit is confirmed, even if the particle distribution function shows steep slopes. After this phase, plasmoids lead to cross-sheet interactions and merging, with new current sheets formed. In this regime a Kolmogorov-like spectrum for the magnetic energy develops over a couple of decades, followed by a dissipation range starting around 5~$d_e$ (electron inertial lengths), showing that multi-sheet reconnection evolves nonlinearly into well-developed turbulence. This phase provides secondary acceleration and further cooling by synchrotron emission, with intermittent radiative bursts. We show that high energy accelerated particles by the primary current sheets are further energized during the turbulent phase, while the distribution of the most energetic particles remains steep.