HF radar observations of Pc 5 field line resonances in the midnight/early morning MLT sector

Journal Article · Sun Sep 01 00:00:00 EDT 1991 · Journal of Geophysical Research; (United States)

DOI:https://doi.org/10.1029/91JA00795· OSTI ID:5180735

Ruohoniemi, J M; Greenwald, R A; Baker, K B ^[1]; Samson, J C ^[2]

---

1. Johns Hopkins Univ., Laurel, MD (United States)
2. Univ. of Alberta, Edmonton (Canada)

On a number of occasions The Johns Hopkins University/Applied Physics Laboratory HF radar at Goose Bay, Labrador, has observed the effects of field line resonances on the drift velocities of irregularities in the F region of the high-latitude ionosphere. One of the most interesting sets of resonances occurs near midnight MLT and may be associated with shear in the convective flow in the magnetotail. This paper discusses in detail a particularly clear example which shows field line resonance equatorward of a region of shear flow in the early morning sector. The motions were predominantly in the geomagnetic east-west direction, indicating north-south electric fields. As expected of field line resonance pulsations, these oscillations had pronounced peaks in their latitudinal power distribution. The pulsations could occur simultaneously but remained distinct as the latitude of peak response was observed to vary inversely with the frequency of the pulsation. The authors interpret these features in terms of field line resonance theory and discuss the possible sources of the pulsation energy.

• OSTI ID: 5180735
• Journal Information: Journal of Geophysical Research; (United States), Vol. 96:A9; ISSN 0148-0227
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
F REGION
HYDROMAGNETIC WAVES
PLASMA DENSITY
ELECTRIC FIELDS
HELMHOLTZ INSTABILITY
LATITUDE EFFECT
MAGNETOSHEATH
MAGNETOTAIL
PLASMA DRIFT
RADAR
RESONANCE
SHEAR
WAVE PROPAGATION
EARTH ATMOSPHERE
EARTH MAGNETOSPHERE
GEOGRAPHICAL VARIATIONS
INSTABILITY
IONOSPHERE
MEASURING INSTRUMENTS
PLANETARY IONOSPHERES
PLASMA INSTABILITY
PLASMA MACROINSTABILITIES
RANGE FINDERS
VARIATIONS
640201* - Atmospheric Physics- Auroral
Ionospheric
& Magetospheric Phenomena