IMF b/sub y/ control of ionization and electric fields measured by the Sondrestrom radar

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

OSTI ID:6512030

Robinson, R M; Clauer, C R; De La Beaujardiere, O; Kelly, J D; Evans, D S

The pattern of ionization and electric fields measured in the dayside auroral zone by the Sondrestrom incoherent scatter radar is compared with interplanetary magnetic field (IMF) data from the IMP-8 spacecraft. The electric-field configuration is most sensitive to the B/sub y/ component of the IMF. For B/sub y/ < 0 there is a strong reversal in convective flow between 1300 and 1600 MLT with a region of enhanced F-region ionization associated with low-energy particle precipitation at the reversal. For B/sub y/ > 0 the convention reversal is most apparent on the morning side. Ionization produced by particle precipitation for B/sub y/ > 0. is much less conspicuous than that observed on the afternoon side for B/sub y/ <0. We show radar measurements of ionization, electric fields and electron temperatures associated with two distinct types of particle precipitation in the pre-noon local time sector for B/sub y/> 0. The patterns of precipitation for B/sub y/ < 0 and B/sub y/ > 0 are consistent with the distribution of field-aligned currents, in that precipitation occurs primarily in the upward current regions. With this interpretation, only the precipitation associated with the cusp-field-aligned currents on the dawn side may be intense enough to produce ionospheric signatures observable from the ground.

• Research Organization: Stanford Univ., CA (USA). Space, Telecommunications and Radioscience Lab.
• OSTI ID: 6512030
• Report Number(s): AD-A-177814/1/XAB
• Country of Publication: United States
• Language: English

Related Subjects

640201* -- Atmospheric Physics-- Auroral
Ionospheric
&amp; Magetospheric Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ALIGNMENT
AURORAL ZONES
CHARGED-PARTICLE PRECIPITATION
CONTROL
DISTRIBUTION
EARTH ATMOSPHERE
ELECTRIC FIELDS
ELECTRONS
ELEMENTARY PARTICLES
F REGION
FERMIONS
INCOHERENT SCATTERING
INTERPLANETARY MAGNETIC FIELDS
INTERPLANETARY SPACE
IONIZATION
IONOSPHERE
LEPTONS
MAGNETIC FIELDS
MEASURING INSTRUMENTS
PARTICLES
PLANETARY IONOSPHERES
RADAR
RANGE FINDERS
SCATTERING
SPACE