This display requires that JavaScripts be enabled in your browser. For instructions, view
Instrument: EFD : Electric Fields Detector (Geotail)
View entire text

Associated Platforms

Related Data Sets
View all records related to this instrument

The objectives of the EFD investigation on Geotail are studies of (1) the large
scale configuration of the electric field in the magnetotail, (2) tail electric
field variations during substorms, (3) the electric field in the plasma sheet,
(4) the electric field near the magnetopause and in the plasma mantle at
locations tailward of those covered by similar measurements on ISEE 1, (5)
micropulsation and low frequency wave measurements at frequencies covering the
local gyrofrequency (<1Hz) and lower hybrid frequency (<10Hz) in the tail, (6)
plasma density as deduced from measurement of the floating potential of the
spacecraft, and (7) electric field comparisons (with the aid of the other
spacecraft in the ISTP program) at different points along the same magnetic
field line, at different points along a common boundary, or in different
regions of the magnetosphere.

The instrument consists of two orthogonal double probes, each of which is a
pair of separated spheres on wire booms that are located in the satellite spin
plane and whose difference of potential is measured. The separation distances
between the pair of sensors are variable and as great as 160 m tip-to-tip. One
operating mode involves length ratios of the two antennas of about 2:1 in order
to verify instrument operation through showing that the electric field
signature is proportional to the boom length. A second reason for two pairs of
wire booms in the satellite spin plane is the requirement for measurements
having a time resolution far better than the satellite spin period.

Principal Investigator:
Dr. Koichiro Tsuruda
The Institute of Space and Astronautical Science
3-1-1 Yoshinodai, Sagamihara
Kannagawa 229, Japan
Phone: 81-427-51-3911 ext. 2501
Fax: 81-427-59-4236


Online Resources

Instrument Logistics
Instrument Start Date: 1992-07-24
Instrument Owner: ISAS, Japan