Statistical Study of Whistler Waves in the Solar Wind at 1 AU

Abstract

Whistler waves are intermittently present in the solar wind, while their origin and effects are not entirely understood. We present a statistical analysis of magnetic field fluctuations in the whistler frequency range (above 16 Hz) based on about 801,500 magnetic field spectra measured over three years aboard ARTEMIS spacecraft in the pristine solar wind. About 13,700 spectra (30 hours in total) with intense magnetic field fluctuations satisfy the interpretation in terms of quasi-parallel whistler waves. We provide estimates of the whistler wave occurrence probability, amplitudes, frequencies and bandwidths. The occurrence probability of whistler waves is shown to strongly depend on the electron temperature anisotropy. The whistler waves amplitudes are in the range from about 0.01 to 0.1 nT and typically below 0.02 of the background magnetic field. The frequencies of the whistler waves are shown to be below an upper bound that is dependent on ${\beta }_e$. The correlations established between the whistler wave properties and local macroscopic plasma parameters suggest that the observed whistler waves can be generated in local plasmas by the whistler heat flux instability. The whistler wave amplitudes are typically small, which questions the hypothesis that quasi-parallel whistler waves are capable to regulate the electron heat flux in the solar wind. We show that the observed whistler waves have sufficiently wide bandwidths and small amplitudes, so that effects of the whistler waves on electrons can be addressed in the frame of the quasi-linear theory.

References in corpus (6)

• Whistler mode waves and the electron heat flux in the solar wind: Cluster observations
• Experimental determination of whistler wave dispersion relation in the solar wind
• Whistler wave generation by halo electrons in the solar wind
• Suprathermal electron strahl widths in the presence of narrow-band whistler waves in the solar wind
• Anisotropies of the magnetic field fluctuations at kinetic scales in the solar wind : Cluster observations
• Effects of electron drift on the collisionless damping of kinetic Alfvén waves in the solar wind

Cited by in corpus (7)

• Alternative high plasma beta regimes of electron heat-flux instabilities in the solar wind
• The Electromagnetic Signature of Outward Propagating Ion-Scale Waves
• On the role of solar wind expansion as a source of whistler waves: scattering of suprathermal electrons and heat flux regulation in the inner heliosphere
• Long-term dynamics driven by resonant wave-particle interactions: from Hamiltonian resonance theory to phase space mapping
• Parker Solar Probe evidence for scattering of electrons in the young solar wind by narrowband whistler-mode waves
• On quasi-parallel whistler waves in the solar wind
• Whistler instabilities from the interplay of electron anisotropies in space plasmas: A quasilinear approach