HR: 0830h
AN: SM51B-0528    [PDF]
TI: Temporal and Spatial Structure of Substorm Associated High Energy Particle Precipitation
AU: * Spanswick, E
EM: emma@phys.ucalgary.ca
AF: Department of Physics and Astronomy, University of Calgary, 2500 University Drive, Calgary, AB T2N 1N4 Canada
AU: Donovan, E
EM: eric@phys.ucalgary.ca
AF: Department of Physics and Astronomy, University of Calgary, 2500 University Drive, Calgary, AB T2N 1N4 Canada
AU: Liu, W
EM: William.Liu@space.gc.ca
AF: Space Science Program Canadian Space Agency, 100 Sussex Drive PO Box 7275, Vanier Postal Station, Ottawa, ON K1L 8E3 Canada
AU: Hiebert, T
EM: hiebert@phys.ucalgary.ca
AF: Department of Physics and Astronomy, University of Calgary, 2500 University Drive, Calgary, AB T2N 1N4 Canada
AU: Henderson, M
EM: mghenderson@lanl.gov
AF: NIS-2 Los Alamos National Laboratory, Los Alamos National Laboratory, Los Alamos, NM 87545 United States
AU: wallis, D
EM: dwallis@eisa.com
AF: Magnametrics, 2340 Briar Hill Drive, Ottawa, ON K1H 7A9 Canada
AU: Honary, F
EM: f.honary@lancaster.ac.uk
AF: Communications Research Centre Lancaster University, Lancaster University, Lancaster, GBR LA1 4Yr
AB: The evolution of the high-energy electron population through the substorm cycle has been studied directly with in situ observations such as those provided by the LANL-SOPA instruments, and indirectly through precipitation seen via riometers, X-ray imagers, and other instruments. Ground-based and other remote sensing techniques provide the advantage of being able to track such disturbances in both space and time, with caveats including the fact that information about the energy of the precipitating particles is limited. Using data from the 13 instrument NORSTAR (formerly CANOPUS) riometer array in north-central Canada, we are examining a large number of substorm events. We are focussing on a transient ``spike'' of significant absorption that occurs during most substorm expansive phases. Seen from any one station, the spike lasts several minutes. More globally, it typically takes tens of minutes to propagate across the NORSTAR array. The propagation is in general a combination of azimuthal (ie., East or West) and poleward. In this paper, we present a statistical comparision between the propagation characteristics of the spike and other substorm features such as dipolarization, auroral bulge, Pi2s, and injections. As well, we present a detailed analysis of several events. Our objective is to determine the magnetospheric source of this transient high energy precipitation.
DE: 2451 Particle acceleration
DE: 2716 Energetic particles, precipitating
DE: 2736 Magnetosphere/ionosphere interactions
DE: 2768 Plasmasphere
DE: 2788 Storms and substorms
SC: SPA - Magnetospheric Physics [SM]
MN: 2003 Fall Meeting