Characterization of wave-particle interactions in the flux pile-up
region of asymmetric reconnection
Abstract
We investigate electron whistler wave activity in the flux pile-up
region of an asymmetric reconnection event at the magnetopause. The
~140Hz waves are right-hand polarized with a wave normal
angle of ~20 degrees and track the magnetic field
strength, consistent with electron whistler waves. Poynting flux
direction indicates that the waves were generated at the reconnection
site. The waves modulated the flux of 500eV electrons propagating
parallel and anti-parallel to the magnetic field, as observed by EDI.
Only two of four MMS spacecraft observe similar wave activity,
suggesting that the waves are isolated within a narrow flux tube. While
it is not possible to use the wave telescope technique, current density
produced by 500eV electrons provides a means of estimating the parallel
wave vector, k, from a single spacecraft. In addition, we fit the FPI
electron parallel energy distribution with a kappa function then use
Liouville mapping with 500eV EDI electrons to determine the parallel
wave potential, 𝝓, and electric field, E. Combining this with the wave
normal angle and Poynting flux direction provides an estimate for the
perpendicular components of k and E.