| الوصف: |
Electron current layers form in various natural and laboratory plasmas and are susceptible to several instabilities. Tearing, driven by current gradients, stands out as a prominent instability in these layers and is considered a potential mechanism for magnetic reconnection in collisionless regimes. Electron inertia serves as a non-ideal factor causing magnetic field lines to break and subsequently reconnect. Another mode driven by current gradients, known as the surface-preserving mode, maintains magnetic field topology. We investigated the kinetic effects on these modes in the presence of finite electron temperatures using two-dimensional particle-in-cell simulations (implemented with the OSIRIS codebase). Temperature stabilizes the tearing mode to a large extent, except at low temperatures, due to increased electron Larmor radius and subsequent magnetic field diffusion. Introducing uniform guide fields revealed that growth rates decrease at higher temperatures due to reduced plasma beta. Conversely, for the surface-preserving mode, growth rates increase with temperature, likely due to enhanced electron flow velocities. Mixed modes, where both tearing and surface-preserving modes coexist, exhibit asymmetric structures characteristic of asymmetric magnetic reconnection. Finally, we propose future research directions building upon our findings. |
