Identification of the propagation mode of a solar wind wave associated with Pc5 pulsations in the magnetosphere
Other literature type
Walker, A. D. M.
Stephenson, J. A. E.
(issn: 1432-0576, eissn: 1432-0576)
arxiv: Physics::Space Physics
A case study of a magnetohydrodynamic (MHD) wave in the solar wind that is
strongly correlated with a magnetospheric field line resonance observed by
the SuperDARN (Super Dual Auroral Radar
Network) radar at Sanae, Antarctica is presented. The data from the ACE (Advanced
Composition Explorer) satellite at the solar libration point are analysed. The
data time series are bandpass filtered at the pulsation frequency and the
analytic signal deduced. From these data the partition of energy between the
field components is computed. It is shown that energy is equally partitioned
between the kinetic energy and transverse magnetic potential energy
densities. The energy flux vector is closely aligned with the background
magnetic field. The transverse magnetic and velocity components are in
antiphase. This is the first identification of the triggering wave as a
transverse Alfvén wave which originates upstream from the space craft and
is propagated to the magnetosphere to trigger the pulsation.