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The magnetization $|Omega_{mathrm e}|/omega_{mathrm{e}}$ is an important parameter in plasma astrophysics, where $Omega_{mathrm e}$ and $omega_{mathrm{e}}$ are the electron gyro-frequency and electron plasma frequency, respectively. It only depends on the mass ratio $m_{mathrm i}/m_{mathrm e}$ and the light-to-Alfven speed ratio $c/v_{mathrm{Ai}}$, where $m_{mathrm i}$ ($m_{mathrm e}$) is the ion (electron) mass, $c$ is the speed of light, and $v_{mathrm{Ai}}$ is the ion Alfven speed. Nonlinear numerical plasma models such as particle-in-cell simulations must often assume unrealistic values for $m_{mathrm i}/m_{mathrm e}$ and for $c/v_{mathrm{Ai}}$. Because linear theory yields exact results for parametric scalings of wave properties at small amplitudes, we use linear theory to investigate the dispersion relations of Alfven/ion-cyclotron and fast-magnetosonic/whistler waves as prime examples for collective plasma behaviour depending on $m_{mathrm i}/m_{mathrm e}$ and $c/v_{mathrm{Ai}}$. We analyse their dependence on $m_{mathrm i}/m_{mathrm e}$ and $c/v_{mathrm{Ai}}$ in quasi-parallel and quasi-perpendicular directions of propagation with respect to the background magnetic field for a plasma with $beta_jsim1$, where $beta_j$ is the ratio of the thermal to magnetic pressure for species $j$. Although their dispersion relations are largely independent of $c/v_{mathrm{Ai}}$ for $c/v_{mathrm{Ai}}gtrsim 10$, the mass ratio $m_{mathrm i}/m_{mathrm e}$ has a strong effect at scales smaller than the ion inertial length. Moreover, we study the impact of relativistic electron effects on the dispersion relations. Based on our results, we recommend aiming for a more realistic value of $m_{mathrm i}/m_{mathrm e}$ than for a more realistic value of $c/v_{mathrm{Ai}}$ in non-relativistic plasma simulations if such a choice is necessary, although $dots$
The nature of the plasma wave modes around the ion kinetic scales in highly Alfvenic slow solar wind turbulence is investigated using data from the NASAs Parker Solar Probe taken in the inner heliosphere, at 0.18 Astronomical Unit (AU) from the sun.
In the present paper, we investigate the power-law behaviour of the magnetic field spectra in the Earths magnetosheath region using Cluster spacecraft data under solar minimum condition. The power spectral density of the magnetic field data and spect
Astrophysical shocks are often collisionless shocks. An open question about collisionless shocks is whether electrons and ions each establish their own post-shock temperature, or whether they quickly equilibrate in the shock region. Here we provide s
Large-scale two-dimensional (2D) full particle-in-cell simulations are carried out for studying the relationship between the dynamics of a perpendicular shock and microinstabilities generated at the shock foot. The structure and dynamics of collision
We examine the dependence of the mass-to-light (M/L) ratio of large-scale structure on cosmological parameters, in models that are constrained to match observations of the projected galaxy correlation function w(rp). For a sequence of cosmological mo