Cluster encounter of a magnetic reconnection diffusion region in the near-Earth magnetotail on September 19, 2003 -: art. no. L19105

We report a clear encounter by the Cluster spacecraft of a magnetic reconnection diffusion region in the near-Earth magnetotail at X-GSM = -17.5 R-E on September 19, 2003. In addition to the reversals of the plasma jets and of GSM-z (similar to normal) component of the magnetic field, clear signatures of Hall quadrupolar (GSM-y) magnetic fields as well as bipolar Hall (GSM-z) electric fields with amplitude up to 80 mV/m directed toward the neutral sheet in both hemispheres were observed. Furthermore, large fluctuations in the electric field perpendicular to the magnetic field with amplitudes reaching 65 mV/m were observed near the separatrices in both hemispheres and in association with local density minima.