Effect of Guiding Field to Low-Frequency Electromagnetic Instabilities in the Collisionless Current Sheet

This paper discuss the effect of guiding field to low-frequency electromagnetic instabilities in the collisionless current sheet with the dispersion relation obtained by collisionless and compressible magnetohydrodynamic model. The results show the guiding field affects on the three-dimensional disturbed propagation waves strongly. （1） On the middle plane of current sheet （z = 0）, if there is not guiding field, no instability observed, but if there is guiding field, instabilities can take place. （2） Near the middle of current sheet （z = 0.2）, the current sheet is instable. With increasing of guiding field, the grow rate increased obviously. The wave mode may be whistler or low-hybrid wave. （3） Near the edge of current sheet （z = 0.8）, the effect of guiding field become not clearly. The instability wave mode is quasi-parallel propagation whistler.