Ground-based imaging of detached arcs, ripples in the diffuse aurora, and patches of 6300- angstrom emission

Journal Article · Mon May 01 04:00:00 EDT 1989 · Journal of Geophysical Research; (USA)

DOI:https://doi.org/10.1029/JA094iA05p05367· OSTI ID:5838334

Mendillo, M; Baumgardner, J ^[1]; Providakes, J ^[2]

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1. Boston Univ., MA (USA)
2. Cornell Univ., Ithaca, NY (USA)

A period of coordinated, multidiagnostic observations of the subauroral ionosphere conducted in April 1985 resulted in a series of optical and plasma characterizations of three distinct phenomena: arcs detached from the diffuse aurora, undulations in the equatorward edge of the diffuse aurora, and isolated patches of emission in the F region trough. The optical features were observed by the 6300-A imaging system in Boston University's Mobile Ionospheric Observatory located at the Millstone Hill observatory; plasma observations were made by the Millstone incoherent scatter radar, Air Force Geophysics Laboratory satellite radio beacon polarimeters, and the Defense Meteorological Satellite Program (DMSP) energetic particle detectors. The detached arc observations showed that strong F region enhancements occurred in both 6300-{angstrom} emission and total plasma content, suggesting an electron precipitation source essentially similar to the plasma sheet population that causes the diffuse aurora and the poleward wall of the F region trough. The rippled features along the equatorward edge of the diffuse aurora were associated with strong electric fields and large radial ion temperature gradients. The isolated and long-lived patches of 6300-{angstrom} emission have no corresponding F region plasma enhancements, but are associated with enhanced radar returns from the E region. Nearly simultaneous DMSP observations point to the importance of ion precipitation effects as a cause for these F region optical and E region plasma enhancements.

• OSTI ID: 5838334
• Journal Information: Journal of Geophysical Research; (USA), Journal Name: Journal of Geophysical Research; (USA) Vol. 94:A5; ISSN 0148-0227; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

640201* -- Atmospheric Physics-- Auroral
Ionospheric
& Magetospheric Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
AURORAE
CHARGED-PARTICLE PRECIPITATION
E REGION
EARTH ATMOSPHERE
ELECTRIC FIELDS
ELECTROMAGNETIC RADIATION
ELECTRON PRECIPITATION
F REGION
GROUND LEVEL
IMAGES
ION TEMPERATURE
IONOSPHERE
LEVELS
PLANETARY IONOSPHERES
RADIATIONS
TEMPERATURE GRADIENTS
VISIBLE RADIATION