Proton fire hose instabilities in the expanding solar wind

Abstract

Using two-dimensional hybrid expanding box simulations we study the competition between the continuously driven parallel proton temperature anisotropy and fire hose instabilities in collisionless homogeneous plasmas. For quasi radial ambient magnetic field the expansion drives $T_{\mathrm{p}\Vert }>T_{\mathrm{p}\perp }$ and the system becomes eventually unstable with respect to the dominant parallel fire hose instability. This instability is generally unable to counteract the induced anisotropization and the system typically becomes unstable with respect to the oblique fire hose instability later on. The oblique instability efficiently reduces the anisotropy and the system rapidly stabilizes while a significant part of the generated electromagnetic fluctuations is damped to protons. As long as the magnetic field is in the quasi radial direction, this evolution repeats itself and the electromagnetic fluctuations accumulate. For sufficiently oblique magnetic field the expansion drives $T_{\mathrm{p}\perp }>T_{\mathrm{p}\Vert }$ and brings the system to the stable region with respect to the fire hose instabilities.

arXiv commentJournal of Plasma Physics, 14 pages, 9 figures

References in corpus (12)

• Magnetic fluctuation power near proton temperature anisotropy instability thresholds in the solar wind
• Firehose and Mirror Instabilities in a Collisionless Shearing Plasma
• Empirical Constraints on Proton and Electron Heating in the Fast Solar Wind
• Whistler mode waves and the electron heat flux in the solar wind: Cluster observations
• Instabilities Driven by the Drift and Temperature Anisotropy of Alpha Particles in the Solar Wind
• Limits on Alpha Particle Temperature Anisotropy and Differential Flow from Kinetic Instabilities: Solar Wind Observations
• Plasma turbulence and kinetic instabilities at ion scales in the expanding solar wind
• Solar wind protons at 1 AU: trends and bounds, constraints and correlations
• Deceleration of Alpha Particles in the Solar Wind by Instabilities and the Rotational Force: Implications for Heating, Azimuthal Flow, and the Parker Spiral Magnetic Field
• Proton temperature-anisotropy-driven instabilities in weakly collisional plasmas: Hybrid simulations
• A Self-Consistent Marginally Stable State for Parallel Ion Cyclotron Waves
• Fire Hose instability driven by alpha particle temperature anisotropy

Cited by in corpus (9)

• Adaptive critical balance and firehose instability in an expanding, turbulent, collisionless plasma
• Electron mirror instability: Particle-in-cell simulations
• Mirror instability in the turbulent solar wind
• Turbulence vs. fire hose instabilities: 3-D hybrid expanding box simulations
• Self-sustaining sound in collisionless, high-beta plasma
• A Heating Mechanism via Magnetic Pumping in the Intracluster Medium
• Particle-In-Cell simulations of the parallel proton firehose instability influenced by the electron temperature anisotropy in solar wind conditions
• Evolution of an Alfvén Wave-Driven Proton Beam in the Expanding Solar Wind
• Formation of Suprathermal Electron Populations in the Expanding, Turbulent Solar Wind