HR: 15:25h
AN: SM52D-07    [PDF]
TI: Mapping the Field-Aligned Currents During a Superstorm
AU: * Burke, W J
EM: william.burke2@hanscom.af.mil
AF: Air Force Research Laboratory, Space Vehicles Directorate, Hanscom AFB, MA 01731 United States
AU: Huang, C Y
EM: cheryl.huang@hanscom.af.mil
AF: ISR, Boston College, 140 Commonwealth Avenue, Chestnut Hill, MA 02467 United States
AB: During the superstorm of April 2000 four DMSP satellites crossed ~ 1A/m sheets of field-aligned current (FAC) that were widely distributed in local time and centered at magnetic latitudes less than $60\deg$. FAC positions relative to particle precipitation boundaries (B2e, B2i), described by Newell et al., [1996], mandate generation sources in the central plasma sheet. The phenomenon repeated four times near the storm's maximum epoch, on each occasion after the AE index indicated a pseudo breakup event. As the evening-sector system decayed, an upward FAC sheet formed near the equatorward boundary of auroral electron precipitation. This requires a westward ion pressure gradient in the inner plasma sheet near 21:00 MLT, consistent with radially differential gradient-curvature drifts subsequent to substorm-like plasma injections into a ring-current inflated inner magnetosphere. Net Poynting fluxes, estimated from measured magnetic and electric field perturbations, indicate that these FACs carry several percent of the total ring-current energy into the mid latitude ionosphere where it dissipates as Joule heat.
DE: 2708 Current systems (2409)
DE: 2716 Energetic particles, precipitating
DE: 2788 Storms and substorms
SC: SPA - Magnetospheric Physics [SM]
MN: 2003 Fall Meeting