Conductance of auroral magnetic field lines

Technical Report · Wed Jan 01 04:00:00 EST 1986

OSTI ID:6845757

Weimer, D R; Gurnett, D A; Goertz, C K

Recent results from the Dynamics Explorer satellites have indicated that in the auroral zone a linear relationship exists between the field-aligned current density and the potential drop parallel to the magnetic field lines. Evidence for this Ohm's law relationship was found in the mapping of perpendicular electric fields and field-aligned currents between high and low altitudes. The mapping depends on the perpendicular wavelength of the electric-field variations. A scale length in the mapping formula is determined by the ratio of the parallel field line conductance and the ionospheric Pedersen conductance. The wavelength and the conductivity ratio also control the relationship between the perpendicular electric and magnetic fields at high altitudes. The short-wavelength limit in the ionospheric conductivity is no longer important in the relationship between the north-south electric field and the east west magnetic field at high altitudes (i.e., above the parallel potential drop). At the short wavelength limit, the relationship takes on a simple form: the integral of the perpendicular electric field results in a potential profile which, according to the linear theory, is proportional to the current density. Assuming that the currents are in the form of infinite sheets orientated east-west, the second integral of the electric field is proportional to the magnetic field.

• Research Organization: Regis Coll., Weston, MA (USA). Research Center
• OSTI ID: 6845757
• Report Number(s): AD-A-174047/1/XAB
• Country of Publication: United States
• Language: English

Related Subjects

640201* -- Atmospheric Physics-- Auroral
Ionospheric
& Magetospheric Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
AURORAE
AURORAL ZONES
CURRENT DENSITY
ELECTRIC FIELDS
FOURIER TRANSFORMATION
GEOMAGNETIC FIELD
INTEGRAL TRANSFORMATIONS
MAGNETIC FIELDS
TRANSFORMATIONS