Science Objectives
The Electric Field and Wave (EFW) experiment on Cluster is designed for
studies of nonlinear wave phenomena that result in acceleration of plasma
as well as large- and small-scale interferometric measurements.
Using four spacecraft for large-scale differential measurements and several
Langmuir probes on one spacecraft for small-scale interferometry, it is
possible to the study motion and shape of plasma structures on a wide range
of spatial and temporal scales.
The Instrument
| EFW |
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The Electric Field and Wave (EFW) experiment on Cluster is designed to
measure the electric field and density fluctuations with sampling rates of
up to 36,000 samples/s, in two channels.
Langmuir sweeps can also be made to determine the electron density and
temperature.
The instrument has several important capabilities. These include:
- measurements of quasi-static electric fields of amplitudes up to
700 mV/ with high time resolution.
- measurements of up to five waveforms of a bandwidth of 4 kHz over short
periods of time.
- measurements of motion of plasma structures and wavefronts with
velocities up to thousands of km/s.
| Configuration on Satellite |
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| CAD drawing showing location of EFW (2) on
spacecraft. During actual operations, boom is deployed.
Also shown are STAFF (1), DWP (3), WHISPER (4) and WBD (5) |
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