Interchange instability at the reconnection jet front in the magnetotail

*Masao Nakamura[1] ,Masaki Fujimoto [2]
Hiroshi Matsumoto [1]
Radio Science Center for Space & Atmosphere, Kyoto University[1]
Department of Earth and Planetary Sciences, Tokyo Institute of Technology[2]

We have investigated the three-dimensional development of the reconnection jet in the magnetotail by hybrid simulations. At the reconnection jet front, the reconnected field lines are piled up and the plasma density is enhanced by compression. The jet front becomes unstable to an interchange instability and deforms itself into a wavy shape. In the non-linear growth phase, the wavy perturbations grow into magnetic bundles in which the reconnected field lines are converged and the bundles move faster than the other parts. This instability can generate localized channels with a cross-tail extent of a few Earth radii, in which plasma and magnetic field transports are achieved, and thus may well be related to the formation of the BBFs in the magnetotail.