Storm time electric field penetration observed at mid-latitude

Journal Article · Mon Apr 01 00:00:00 EST 1991 · Journal of Geophysical Research; (United States)

DOI:https://doi.org/10.1029/90JA02751· OSTI ID:5223258

Yeh, H C; Foster, J C ^[1]; Rich, F J; Swider, W ^[2]

---

1. Massachusetts Insti. of Tech., Westford (USA)
2. Geophysics Lab., Hanscom AFB, MA (USA)

During the height of the February 8-9, 1986, magnetic storm the Millstone Hill radar was in the evening local time sector (1600-2200 MLT). Radar observations indicate that high speed (>1,000 m s{sup {minus}1}) westward ion flow penetrated deeply below 50{degree} invariant latitude ({Lambda}) and persisted for 6 hours between 2100 UT on February 8 and 0300 UT on February 9. The double-peaked ion convection feature was pronounced throughout the period, and the separation in the dual maxima ranged from 4{degree} to 10{degree}. The latitude positions of the high-latitude ion drift peak and the convection reversal varied in unison. The low-latitude ion drift peak ({approximately}49{degree}{Lambda} or L =2.3) did not show significant universal time/magnetic local time (UT/MLT) variation in its latitude location but showed a decrease in magnitude during the initial recovery phase of the storm. Using simultaneous particle (30 eV-30 keV) precipitation data from the DMSP F6 and F7 satellites, the authors find the high-latitude ion drift peak to coincide with the boundary plasma sheet/central plasma sheet transition in the high ionospheric conductivity (>15 mho) region. The low-latitude ion drift peak lay between the equatorward edges of the electron and soft (< 1 keV) ion precipitation in the low conductivity region ({approximately}1 mho). A comparison between the low-altitude observations and simultaneous ring current observations from the high-altitude AMPTE satellite further suggests that the low-altitude ion drift peak is closely related to the maximum of the O{sup +} dominated ring current energy density in magnetic latitude. The low-latitude ion drift peak is the low-altitude signature of the electric field shielding effect associated with ring current penetration into the outer layer of the storm time plasmasphere.

• OSTI ID: 5223258
• Journal Information: Journal of Geophysical Research; (United States), Vol. 96:A4; ISSN 0148-0227
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
EARTH MAGNETOSPHERE
ELECTRIC FIELDS
MAGNETIC STORMS
CHARGED-PARTICLE PRECIPITATION
COMPARATIVE EVALUATIONS
DYNAMICS
ELECTRIC CONDUCTIVITY
ELECTRON PRECIPITATION
HEIGHT
ION DRIFT
LATITUDE EFFECT
PLASMA SHEET
PLASMASPHERE
RADAR
DIMENSIONS
EARTH ATMOSPHERE
ELECTRICAL PROPERTIES
EVALUATION
GEOGRAPHICAL VARIATIONS
MEASURING INSTRUMENTS
MECHANICS
PHYSICAL PROPERTIES
RANGE FINDERS
VARIATIONS
640201* - Atmospheric Physics- Auroral
Ionospheric
&amp; Magetospheric Phenomena