Solar-wind dependencies of high-latitude convection and precipitation

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

OSTI ID:6267893

Foster, J C; Holt, J M; Musgrove, R G; Evans, D S

The solar-wind plasma and interplanetary magnetic field (IMF) dependencies of the patterns of plasma convection and particle precipitation in the high-latitude ionosphere were investigated by constructing average patterns of the ionospheric electric field and the precipitating energy influx of different solar-wind conditions. A data base of over 100 days' observations of high-latitude plasma convection with the Millstone Hill radars was sorted and binned according to the one-hour averaged values of MF Bz and Bv. The individual line of sight velocities observed by the radar were combined in each magnetic latitude-local time bin to derive statistically averaged convection patterns between 50 and 73 degrees latitude. A 25-mV/m southward electric field is found at auroral latitudes in the midnight sector for IMF away sectors (By>O) while a southward-directed IMF increases the cross polar-cap potential difference from 15 kV (for Bz>+3 nT) to 75 kV (for Bz<-3 nT). For geomagnetically disturbed conditions (Kp=-to 5-), the additional requirement that Bz be negative results in a 30-kV potential difference across an enhanced dayside region of plasma entry into the polar cap.

• Research Organization: Haystack Observatory, Westford, MA (USA)
• OSTI ID: 6267893
• Report Number(s): AD-A-180875/7/XAB
• Country of Publication: United States
• Language: English

Related Subjects

640104 -- Astrophysics &amp; Cosmology-- Solar Phenomena
640201* -- Atmospheric Physics-- Auroral
Ionospheric
&amp; Magetospheric Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
AURORAE
CHARGED-PARTICLE PRECIPITATION
CONVECTION
EARTH ATMOSPHERE
ELECTRIC FIELDS
ELECTRON PRECIPITATION
ENERGY
ENERGY TRANSFER
HEAT TRANSFER
INTERACTIONS
INTERPLANETARY MAGNETIC FIELDS
IONOSPHERE
MAGNETIC FIELDS
MASS TRANSFER
MEASURING INSTRUMENTS
PLANETARY IONOSPHERES
POLAR REGIONS
RADAR
RANGE FINDERS
SOLAR ACTIVITY
SOLAR WIND
VELOCITY