2011 SuperDARN Workshop       

Analysis of waves at the magnetopause during a period of FLR activity recorded by the SANAE radar

J.A.E. Stephenson and A.D.M. Walker
School of Physics, University of KwaZulu-Natal, Durban, South Africa

abstract. In the past, we have identified events which show that coherent waves observed in the solar wind near the libration point are phase locked with field line resonances of the same frequency observed by the Sanae radar. We now apply the same techniques to CLUSTER data to obtain the wave behaviour near the magnetopause. Previous analysis of solar wind observations for one event demonstrated that the wave was transverse Alfven. This same method, whereby components of the thermal pressure, density and vector components of the velocity and magneyic field are analyzed, is employed here once more. Complex demodulation is applied to a multiple taper spectrum of each of these components and the resulting waves are examined to determine which of them was the major contributor to the energy flux vector. In addition, comparison of the phase and amplitude allows for the determination of the polarization of the wave. This analysis is intended to provide more evidence, and increase understanding, of the mechanism by which pulsations in the solar wind may drive field line resonances.

Sakaguchi KaoriNICT Japan