Compressive high-frequency waves riding on an Alfvén/ion-cyclotron wave in a multi-fluid plasma

Abstract

In this paper, we study the weakly-compressive high-frequency plasma waves which are superposed on a large-amplitude Alfvén wave in a multi-fluid plasma consisting of protons, electrons, and alpha particles. For these waves, the plasma environment is inhomogenous due to the presence of the low-frequency Alfvén wave with a large amplitude, a situation that may apply to space plasmas such as the solar corona and solar wind. The dispersion relation of the plasma waves is determined from a linear stability analysis using a new eigenvalue method that is employed to solve the set of differential wave equations which describe the propagation of plasma waves along the direction of the constant component of the Alfvén wave magnetic field. This approach also allows one to consider weak compressive effects. In the presence of the background Alfvén wave, the dispersion branches obtained differ significantly from the situation of a uniform plasma. Due to compressibility, acoustic waves are excited and couplings between various modes occur, and even an instability of the compressive mode. In a kinetic treatment, these plasma waves would be natural candidates for Landau-resonant wave-particle interactions, and may thus via their damping lead to particle heating.

15 pages, 5 figures

References in corpus (6)

• Perpendicular Ion Heating by Low-Frequency Alfven-Wave Turbulence in the Solar Wind
• A turbulence-driven model for heating and acceleration of the fast wind in coronal holes
• Constraining Low-Frequency Alfvenic Turbulence in the Solar Wind Using Density Fluctuation Measurements
• A Kinetic Alfven wave cascade subject to collisionless damping cannot reach electron scales in the solar wind at 1 AU
• The Heating of Test Particles in Numerical Simulations of Alfvenic Turbulence
• Solar Wind Electric Fields in the Ion Cyclotron Frequency Range

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• Magnetohydrodynamic Slow Mode with Drifting He${}^{++}$: Implications for Coronal Seismology and the Solar Wind
• Modeling hot, anisotropic ion beams in the solar wind motivated by the Parker Solar Probe observations near perihelia