HR: 0800h
AN: SM31B-0454 [Abstracts]
TI: Multi-Instrument Observations of Pc 3-4 Pulsations at Cusp Latitudes in Svalbard, Norway
AU: * Lu, F
EM: lu@augsburg.edu
AF: Augsburg College, Department of Physics
2211 Riverside Ave, St. Paul, MN 55454, United States
AU: Engebretson, M
EM: engebret@augsburg.edu
AF: Augsburg College, Department of Physics
2211 Riverside Ave, St. Paul, MN 55454, United States
AU: Lessard, M
EM: marc.lessard@unh.edu
AF: University of New Hampshire, Space Science Center and Department of Physics
417 Morse Hall, Durham, NH 03824, United States
AU: Kim, H
EM: hyomin.kim@unh.edu
AF: University of New Hampshire, Space Science Center and Department of Physics
417 Morse Hall, Durham, NH 03824, United States
AU: Wright, D
EM: Darren.Wright@ion.le.ac.uk
AF: University of Leicester, Radio and Space Plasma Physics Group
Department of Physics & Astronomy
University Road
Leicester, LE1 7RH, UK, Leicester, LE1 7RH, United Kingdom
AB:
It has been generally accepted that Pc 3-4 pulsations (~ 10-100 mHz) originate in the ion foreshock upstream of
the bow shock due to the interaction between reflected ions and the solar wind, but it is not clear how these
waves propagate to the high-latitude ionosphere. Many early studies noted increased power in the vicinity of the
dayside cusp. In this study, we compared signal power at Pc 3-4 frequencies from searchcoil magnetometers at
three closely-spaced stations on Svalbard: Ny Alesund (76.31o Magnetic Latitude), Longyearbyen (75.26o
Magnetic Latitude) and Hornsund (74.24o Magnetic Latitude). Data from the SuperDARN Finland HF radar and
DMSP satellites were used to accurately locate the cusp latitudes. We found several events where
magnetometers showed strong, narrow-band Pc 3-4 signals, while during the same period the SuperDARN
radar saw a clear-edged cusp and a DMSP satellite passing overhead observed the typical cusp signature. We
found that often the wave packets were localized and linearly polorized. Also most of the time, the signals were
strongest equatorward of the cusp, consistent not with entry via the cusp proper but along field lines equatorward
of the cusp which map to the boundary layer or outer magnetosphere.
DE: 2706 Cusp
DE: 2716 Energetic particles: precipitating
DE: 2728 Magnetosheath
DE: 2736 Magnetosphere/ionosphere interactions (2431)
DE: 2784 Solar wind/magnetosphere interactions
SC: SPA-Magnetospheric Physics [SM]
MN: 2007 Fall Meeting