Search Publications
On the Existence of the Kolmogorov Inertial Range in the Terrestrial Magnetosheath Turbulence
Sahraoui, F.; Deng, X. H.; Huang, S. Y. +2 more
In the solar wind, power spectral density (PSD) of the magnetic field fluctuations generally follow the so-called Kolmogorov spectrum f -5/3 in the inertial range, where the dynamics is thought to be dominated by nonlinear interactions between counter-propagating incompressible Alfvén wave parquets. These features are thought to be ubiq…
Coherent Structures at Ion Scales in Fast Solar Wind: Cluster Observations
Maksimovic, M.; Alexandrova, O.; Lion, S. +5 more
We investigate the nature of magnetic turbulent fluctuations, around ion characteristic scales, in a fast solar wind stream, by using Cluster data. Contrarily to slow solar wind, where both Alfvénic (δ {b}\perp \gg δ {b}\parallel ) and compressive (δ {b}\parallel \gg δ {b}\perp ) coherent structures are …
Properties of Turbulence in the Reconnection Exhaust: Numerical Simulations Compared with Observations
Sorriso-Valvo, L.; Goldman, M. V.; Newman, D. L. +6 more
The properties of the turbulence that develops in the outflows of magnetic reconnection have been investigated using self-consistent plasma simulations, in three dimensions. As commonly observed in space plasmas, magnetic reconnection is characterized by the presence of turbulence. Here we provide a direct comparison of our simulations with report…
High-resolution Statistics of Solar Wind Turbulence at Kinetic Scales Using the Magnetospheric Multiscale Mission
Russell, C. T.; Fuselier, S. A.; Torbert, R. B. +10 more
Using data from the Magnetospheric Multiscale (MMS) and Cluster missions obtained in the solar wind, we examine second-order and fourth-order structure functions at varying spatial lags normalized to ion inertial scales. The analysis includes direct two-spacecraft results and single-spacecraft results employing the familiar Taylor frozen-in flow a…
Variability of the Magnetic Field Power Spectrum in the Solar Wind at Electron Scales
Escoubet, C. P.; Alexandrova, O.; Turc, L. +4 more
At electron scales, the power spectrum of solar-wind magnetic fluctuations can be highly variable and the dissipation mechanisms of the magnetic energy into the various particle species is under debate. In this paper, we investigate data from the Cluster mission’s STAFF Search Coil magnetometer when the level of turbulence is sufficiently high tha…
Anisotropies of the Magnetic Field Fluctuations at Kinetic Scales in the Solar Wind: Cluster Observations
Alexandrova, Olga; Matteini, Lorenzo; Lacombe, Catherine
We present the first statistical study of the anisotropy of the magnetic field turbulence in the solar wind between 1 and 200 Hz, I.e., from proton to sub-electron scales. We consider 93 ten-minute intervals of the Cluster/STAFF measurements. We find that the fluctuations δ {B}\perp 2 are not gyrotropic at a given frequency f…
Mirror Instability in the Turbulent Solar Wind
Franci, Luca; Landi, Simone; Hellinger, Petr +2 more
The relationship between a decaying strong turbulence and the mirror instability in a slowly expanding plasma is investigated using two-dimensional hybrid expanding box simulations. We impose an initial ambient magnetic field perpendicular to the simulation box, and we start with a spectrum of large-scale, linearly polarized, random-phase Alfvénic…
Three-dimensional Simulations and Spacecraft Observations of Sub-ion Scale Turbulence in the Solar Wind: Influence of Landau Damping
Passot, T.; Sahraoui, F.; Henri, P. +5 more
Three-dimensional nonlinear finite Larmor radius (FLR)-Landau fluid simulations, which include some small-scale ({k}\perp {ρ }I≳ 1) kinetic effects, are performed to explore the nature of the sub-ion scale turbulence in the solar wind and to investigate the role of Landau damping and FLR corrections. The resulting steady-stat…
The Dynamics of Very High Alfvén Mach Number Shocks in Space Plasmas
Burgess, David; Sulaiman, Ali H.; Sundberg, Torbjörn +2 more
Astrophysical shocks, such as planetary bow shocks or supernova remnant shocks, are often in the high or very-high Mach number regime, and the structure of such shocks is crucial for understanding particle acceleration and plasma heating, as well inherently interesting. Recent magnetic field observations at Saturn’s bow shock, for Alfvén Mach numb…
Direct Measurement of Anisotropic and Asymmetric Wave Vector Spectrum in Ion-scale Solar Wind Turbulence
Escoubet, C. P.; Narita, Y.; Roberts, O. W.
This analysis represents the first time that a simultaneous measurement of parallel and perpendicular spectral indices at both inertial and kinetic scales has been made directly in wave vector space, using a single interval of solar wind plasma. An interferometric wave vector analysis method is applied to four-point magnetometer data from the Clus…