Temporal and spatial variation of HF-pump wave enhanced O(1D)　excitation

*B. Gustavsson[1] ,B. U. E. Brandstrom [2],T. Aso [1]
M. T. Rietveld [3],F. Honary [4],T. Sergienko [2]
A. Steen [5]
National Institute of Polar Research, Tokyo, Japan[1]
Swedish Institute of Space Physics, Kiruna Division, Sweden[2]
Max-Planck Institut fur Aeronomie, Germany, Also at EISCAT, Ramfjordmoen, Norway[3]
Department of Communication Systems, Lancaster University, Lancaster, England[4]
Remspace, Linkoping Sweden[5]

There are several open questions in the field of high power HF radio wave interaction with the ionospheric electrons, in particular regarding the processes that lead to enhanced emission of airglow in the visible region of the spectra. By multi station imaging of the enhanced airglow region it has been possible to determine the spatial and temporal variation of both the enhanced emission of airglow in the 630 nm emission from O(1D) as well as the enhanced excitation of the emitting O(1D) state. Whereas the enhanced Emission is a direct observable quantity the excitation is a quantity closer to the HF pump wave ionosphere interaction procewss. In this report we present the first estimates of the time variation of the enhanced three-dimensional excitation rate of O(1D). A region of enhanced airglow was imaged with 10 s time resolution by three stations in the Auroral Large Imaging System (ALIS) in northern Scandinavia. These images allowed for a tomography-like inversion of the volume emission of the airglow. The time variation of the intensity, position and shape of the O(1D) excitation could be derived. This report focuses on the temporal and spatial estimates of the O1D excitation.