First results of electric field and density observations by Cluster EFW based on initial months of operation

Highlights are presented from studies of the electric field data from various regions along the Cluster orbit. They all point towards a very high coherence for phenomena recorded on four spacecraft that are separated by a few hundred kilometers for structures over the whole range of apparent frequencies from 1 mHz to 9 kHz. This presents completely new opportunities to study spatial-temporal plasma phenomena from the magnetosphere out to the solar wind. A new probe environment was constructed for the CLUSTER electric field experiment that now produces data of unprecedented quality. Determination of plasma flow in the solar wind is an example of the capability of the instrument.Key words. Magnetospheric physics (electric fields) – Space plasma physics (electrostatic structures; turbulence