Turbulence and Nonthermal Particle Acceleration in 3D Magnetic Reconnection

Understanding plasma dynamics and nonthermal particle acceleration in 3D magnetic reconnection has been a long-standing challenge. We explore these problems by performing fully kinetic simulations with various parameters in both the weak and strong guide field regimes. In each regime, we have identified its unique 3D dynamics that leads to field-line chaos and efficient acceleration, and we have achieved nonthermal acceleration of both electrons and protons into power-law spectra. In the low-guide-field regime, the flux-rope kink instability governs the 3D dynamics for efficient acceleration. As the guide field becomes stronger, the oblique flux ropes capture the main 3D dynamics for efficient acceleration. We analyze the turbulence properties and discuss particle acceleration processes. This work has broad implications for 3D reconnection dynamics and particle acceleration in heliophysics and astrophysics.