Fig. 2: Features of the filamentary currents around the X-line.

a–c Three components of the current density. d The magnitude of current density (black curve), and the background current density (red curve) observed by MMS1. e The magnitude of current density (black curve), and the background current density (red curve) observed by MMS4. f Three components of the disturbed magnetic field δB. The background magnetic fields below fci (0.14 Hz) have been removed. g The comparisons between E⊥ with \(-({{{{{{\bf{V}}}}}}}_{e}\times {{{{{\bf{B}}}}}})\) and \(-({{{{{{\bf{V}}}}}}}_{{{{{{\rm{i}}}}}}}\times {{{{{\bf{B}}}}}})\) in Y-GSE direction. The area between two vertical black dashed lines at 03:58:07 and 03:58:43 UT represents the X-line region.