HR: 1400h
AN: SM33A-06    [Abstracts]
TI: Observations of Pc3-4 Pulsations in the Cusp Region using Four Closely-spaced Cusp- Latitude Search-coil Magnetometers, All-sky Imagers, and the EISCAT Svalbard Radar
AU: Lu, F
EM: lu@augsburg.edu
AF: Augsburg College, Department of Physics 2211 riverside ave, Minneapolis, MN 55454, United States
AU: * Engebretson, M
EM: engebretson@augsburg.edu
AF: Augsburg College, Department of Physics 2211 riverside ave, Minneapolis, MN 55454, United States
AU: Lessard, M
EM: marc.lessard@unh.edu
AF: University of New Hampshire, Department of Physics University of New Hampshire, Durham, NH 03824, United States
AU: Kim, H
EM: hyomin.kim@unh.edu
AF: University of New Hampshire, Department of Physics University of New Hampshire, Durham, NH 03824, United States
AU: Moen, J
EM: Joran.Moen@unis.no
AF: University of Oslo, Department of Physics University of Oslo, Oslo, Norway, Oslo, Norway
AU: Lorentzen, D
EM: dagl@unis.no
AF: The University Centre in Svalbard, Longyearbyen, Svalbard, Longyearbyen Norway, Longyearbyen, Norway
AB: A two-dimensional, closely-spaced four-station array of search-coil magnetometers was set up on the Svalbard archipelago in September, 2006, at geomagnetic latitudes ranging from 74° to 76° N. These stations can take advantage of the many other observational instruments on Svalbard, including optical instruments and the EISCAT incoherent scatter radar. We report here on observations of Pc3-4 pulsations at these sites, which are commonly thought to originate in the solar wind's ion foreshock upstream from Earth's bow shock and have long been known to be especially intense in near-cusp regions. The path or paths by which these waves travel from upstream to the near-cusp ionosphere is, however, still controversial. Data obtained during northern winter 2006-2007, when the cusp footpoint was in darkness, have shown that the Pc3-4 wave amplitude was typically but not always larger at the lower latitude station, just equatorward of the nominal cusp latitude. Further study of these data, including analysis of relative phase of the waves and comparison with optical and radar data will help determine whether the region of wave transmission to low altitudes is via the cusp, boundary layer, or slightly deeper in the magnetosphere.
DE: 2700 MAGNETOSPHERIC PHYSICS (6939)
DE: 2736 Magnetosphere/ionosphere interactions (2431)
DE: 2772 Plasma waves and instabilities (2471)
DE: 2784 Solar wind/magnetosphere interactions
DE: 2788 Magnetic storms and substorms (7954)
SC: SPA-Magnetospheric Physics [SM]
MN: 2007 Joint Assembly