Dense magnetospheric plasma and Kelvin-Helmholtz waves

Abstract:

The coupling of energy between the solar wind and a planetary magnetosphere is a function of the plasma parameters on both sides of the planet's magnetopause. Scientists routinely monitor the changing conditions in the solar wind in efforts to predict the dynamics at the magnetopause, but there can also be significant changes within the magnetosphere that play a role. On the magnetospheric side, the plasma density can change by several orders of magnitude (0.1cm-3 to 50cm-3). The current study investigates the role of dense magnetospheric plasma in the formation of Kelvin-Helmholtz waves at the magnetopause boundary. Spacecraft observations and SuperDARN radar measurements are presented showing the occurrence of Kelvin-Helmholtz waves on the dayside magnetopause under relatively low shear flows in the presence of a dense plasmaspheric plume.