Whistler Wave and Hall Effect in Magnetic Reconnection

The effects of Hall current on the reconnection dynamics and wave behavior are numerically studied in this report. The notable reductions in the openness of outflow region and the reconnection rate are shown as Hall effect weakens. The time series of the out-of-plane magnetic field By and the velocity components vx, vz in the (x, z) plane at the given points are transferred into the power spectra by the Fast Fourier Transformation (FFT) for the cases with various intensive Hall terms. Using the Minimum Variance Analysis (MVA) on E, the propagation directions and the polarized features of waves are determined. It can be found that there exists the whistler wave with the typical features near the magnetic separatrices in the case of the stronger Hall effect and the wave signature weakens substantially as the intensity of Hall effect is reduced. These results indicate that Hall effect has an important influence on the reconnection dynamics and plays a crucial role in generating the whistler-mode wave and fast reconnection rate. Besides, there is a positive coherency between the amplitude of whistler wave and the field-aligned current Jp in the plane near the magnetic separatrices in the case with the strong Hall term. It demonstrates the closed linkage between the whistler wave and Hall effect on the other hand.