Ion outflow observed by IMAGE: Implications for source regions and heating mechanisms

S. A. Fuselier, A. G. Ghielmetti, T. E. Moore, M. R. Collier, J. M. Quinn, 
G.R. Wilson, P. Wurz, S. B. Mende, H. U. Frey, C. Jamar, J.-C. Gerard, and J.L. Burch


Images of the Earth's proton aurora from the IMAGE spacecraft on 8 June 2000 indicate 
a temporally and spatially isolated ionospheric response to a shock that impinged on 
the Earth.s magnetopause. Sometime after this ionospheric response, the Low Energy 
Neutral Atom imager on IMAGE detected enhanced ionospheric outflow. The time delay 
between the ionospheric response and the enhanced outflow is consistent with the 
travel time of ~30 eV neutral Oxygen (created by charge exchange of outflowing O + 
with the exosphere) from the low altitude ionosphere to the spacecraft. The prompt 
ionospheric outflow implies that the shock deposited sufficient energy in the topside 
ionosphere near or above the O + exobase to initiate the outflow. 

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Geophysical Research Letters, Vol. 28, No. 6, p. 1163, 2001.