Conditions for proton temperature anisotropy to drive instabilities in the solar wind
arXiv:2210.04875 · doi:10.3847/1538-4357/ac982f
Abstract
Using high-resolution data from Solar Orbiter, we investigate the plasma conditions necessary for the proton temperature anisotropy driven mirror-mode and oblique firehose instabilities to occur in the solar wind. We find that the unstable plasma exhibits dependencies on the angle between the direction of the magnetic field and the bulk solar wind velocity which cannot be explained by the double-adiabatic expansion of the solar wind alone. The angle dependencies suggest that perpendicular heating in Alfvénic wind may be responsible. We quantify the occurrence rate of the two instabilities as a function of the length of unstable intervals as they are convected over the spacecraft. This analysis indicates that mirror-mode and oblique firehose instabilities require a spatial interval of length greater than 2 to 3 unstable wavelengths in order to relax the plasma into a marginally stable state and thus closer to thermodynamic equilibrium in the solar wind. Our analysis suggests that the conditions for these instabilities to act effectively vary locally on scales much shorter than the correlation length of solar wind turbulence.
arXiv comment16 pages, 8 figures. Accepted for publication in ApJ
References in corpus (35)
- The Solar Orbiter mission -- Science overview
- Astrophysical gyrokinetics: kinetic and fluid turbulent cascades in magnetized weakly collisional plasmas
- Magnetic fluctuation power near proton temperature anisotropy instability thresholds in the solar wind
- The multi-scale nature of the solar wind
- A Model of Turbulence in Magnetized Plasmas: Implications for the Dissipation Range in the Solar Wind
- Astrophysical Gyrokinetics: Basic Equations and Linear Theory
- Solar Wind Turbulence and the Role of Ion Instabilities
- Gyrokinetic Simulations of Solar Wind Turbulence from Ion to Electron Scales
- Recent progress in astrophysical plasma turbulence from solar wind observations
- Firehose and Mirror Instabilities in a Collisionless Shearing Plasma
- Incorporating Kinetic Physics into a Two-Fluid Solar-Wind Model with Temperature Anisotropy and Low-Frequency Alfven-Wave Turbulence
- The Solar Orbiter Science Activity Plan: translating solar and heliospheric physics questions into action
- Magnetorotational Turbulence and Dynamo in a Collisionless Plasma
- Proton Kinetic Effects in Vlasov and Solar Wind Turbulence
- Multi-Species Measurements of the Firehose and Mirror Instability Thresholds in the Solar Wind
- The Role of Turbulence in Coronal Heating and Solar Wind Expansion
- A Dynamical Model of Plasma Turbulence in the Solar Wind
- On Kinetic Slow Modes, Fluid Slow Modes, and Pressure-balanced Structures in the Solar Wind
- A Majority of Solar Wind Intervals Support Ion-Driven Instabilities
- Collisionless Isotropization of the Solar-Wind Protons by Compressive Fluctuations and Plasma Instabilities
- Inertial-Range Kinetic Turbulence in Pressure-Anisotropic Astrophysical Plasmas
- Enhanced proton parallel temperature inside patches of switchbacks in the inner heliosphere
- On the probability distribution function of small scale interplanetary magnetic field fluctuations
- Solar wind turbulence from MHD to sub-ion scales: high-resolution hybrid simulations
- Evolution of turbulence in the expanding solar wind, a numerical study
- Nonlinear and Linear Timescales near Kinetic Scales in Solar Wind Turbulence
- Plasma turbulence and kinetic instabilities at ion scales in the expanding solar wind
- Apparent temperature anisotropies due to wave activity in the solar wind
- Observations of heating along intermittent structures in the inner heliosphere from PSP data
- Self-Consistent Ion Cyclotron Anisotropy-Beta Relation for Solar Wind Protons
- Mirror instability in the turbulent solar wind
- The Impact of Turbulent Solar Wind Fluctuations on Solar Orbiter Plasma Proton Measurements
- Mixing the solar wind proton and electron scales. Theory and 2D-PIC simulations of firehose instability
- Deriving the bulk properties of solar wind electrons observed by Solar Orbiter: A preliminary study of electron plasma thermodynamics
- On the applicability of Taylor's hypothesis in streaming magnetohydrodynamic turbulence