Ion behaviour in the vicinity of ballooning-interchange heads

Comparison of THEMIS spacecraft observations with kinetic simulations suggested that the kinetic Ballooning/Interchange Instability (BICI) may lead to erosion and thinning of the magnetotail current sheet at fluid scales due to side vorticity and associated an FLR effect and at ion scales by means of EMIC waves. The FLR effect may lead to ion temperature asymmetry on the two sides of BICI heads in the course of ion redistribution between the dusk- and dawnside vortices around the neutral sheet. On top of that, the EMIC waves may propagate in both azimuthal directions and modulate the ion density and velocity above and below the neutral sheet. As this activity may be important for turning Bz southward and possibly initiating magnetic reconnection in the magnetotail, we show high-resolution MMS ion observations with signatures of the two processes now in the MMS magnetotail bursty bulk flow observations and aim at finding evidence that the field and particle behaviour was caused by the two effects.