Collisionless magnetic reconnection in a three-dimensional open system

摘要: Two-dimensional (2-D) simulations of collisionless magnetic reconnection have demonstrated the importance Hall term for structure diffusion region and existence a very thin (∼ c/ωpe) electron current layer sharp density/pressure gradients on c/ωpi scales. The present work explores effects third dimension (along direction equilibrium current) an open geometry along field these 2-D structures within fully kinetic treatment based particle-in-cell simulations. is found to remain structure. electric components Ez E‖ in each possess complex c/ωpe spatial fields are needed maintain pressure balance ion species sheet, while results nearly Alfvenic (for ions) supra-Alfvenic electrons) flows out region. Hall-generated quadrupolar By extends large distances away from neutral line characteristic signature reconnection. No evidence development small-scale turbulent modes; highly ballistic, currents density sharply defined. outflow region, however, can become unstable ideal gradient instability relatively long wavelength (kyw ∼ 0.25, where w half thickness sheet) with character kink or interchange mode. Attempts induce localized by imposing (in y) convection at asymptotic (lobe) boundaries do not alter appreciably basic configuration.