We consider series of tilted current sheet crossings,corresponding to flapping waves in the near-Earth magnetotail. We analyseCluster observations from 2005 to 2009, when spacecraft visited themagnetotail neutral plane near ∈ [ − 17, − 8], ∈ [ − 16, − 2] (in the GSMsystem). Large separation of spacecraft allows us to estimate both local andglobal properties of flapping current sheets. We find significant variationin flapping wave direction of propagation between the middle tail and flanks. Thseries of tilted current sheets represent the system of periodic, almostparallel currents with typical thickness of current filaments about = 0.4 . The earthward gradients of magnetic field are reduced within thiscurrent system in comparison with the gradients in the quiet near-Earthmagnetotail. The wavelength (i.e. a distance between two crossings ofcurrent sheets with the same orientations) of the flapping waves is largerthan 2 for most of observations. The velocity of flapping wave propagationis about ion bulk velocity and is significantly lower than the velocity ofion drift relative to electrons. We discuss possible drivers of flapping andestimate the amplitude of the total parallel current generated by flappingwaves.
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