Experimental determination of whistler wave dispersion relation in the solar wind

Abstract

The origins and properties of large amplitude whistler wave packets in the solar wind are still unclear. In this Letter we utilise single spacecraft electric and magnetic field waveform measurements from the ARTEMIS mission to calculate the plasma frame frequency and wavevector of individual wave packets over multiple intervals. This allows direct comparison of experimental measurements with theoretical dispersion relations to identify the observed waves as whistler waves. The whistlers are right-hand circularly polarised, travel anti-sunward and are aligned with the background magnetic field. Their dispersion is strongly affected by the local electron parallel beta in agreement with linear theory. The properties measured are consistent with the electron heat flux instability acting in the solar wind to generate these waves.

Accepted for publication in ApJ Letters

References in corpus (1)

• Whistler mode waves and the electron heat flux in the solar wind: Cluster observations

Cited by in corpus (6)

• Statistical Study of Whistler Waves in the Solar Wind at 1 AU
• Scattering of Strahl Electrons in the Solar Wind between 0.3 and 1 au: Helios Observations
• Whistler wave generation by halo electrons in the solar wind
• Quasilinear Approach of the Whistler Heat-Flux Instability in the Solar Wind
• Variability Of The Magnetic Field Power Spectrum In The Solar Wind At Electron Scales
• Anisotropies of the magnetic field fluctuations at kinetic scales in the solar wind : Cluster observations