Determination of the quiet time current sheet thickness using Geotail CPI data and nonlinear dynamics modeling

Abstract

[1] In this paper we present a survey of the quiet (Kp < 1+) current sheet thickness for X GSE between -20 R E and -80 R E as determined from an ion distribution function signature of nonlinear particle dynamics in current sheet-like magnetic fields. The signature manifests itself as a series of peaks in the ion distribution function whose separation depend on the fourth root of the energy and parameters that describe the current sheet structure. We have found clear evidence of the distribution function signature throughout the entire region of interest. Analysis of the data shows that the current sheet thickness is remarkably uniform in the region under study with an average thickness of 0.76 ± 0.56 R E . This result is consistent with measurements of the quiet time current sheet thickness made using other techniques.