相关论文: Electromagnetic ion cyclotron instability stimulat…
Turbulence is often invoked to explain the origin of nonthermal particles in space and astrophysical plasmas. By means of 3D fully kinetic particle-in-cell simulations, we demonstrate that turbulence in low-$\beta$ plasmas ($\beta$ is the…
In the innermost regions of low-luminosity accretion flows, including Sgr A* at the center of our Galaxy, the frequency of Coulomb collisions is so low that the plasma is two-temperature, with the ions substantially hotter than the…
It is shown that the transport in low temperature, collisional, bounded plasma is enhanced by instabilities at high magnetic field. While the magnetic field confines the electrons in a stable plasma, the instability completely destroys the…
The isotropization process of a collisionless plasma with an electron temperature anisotropy along an external magnetic field ($T_\| ^e\gg T_\perp^e$, $\|$ and $\perp$ with respect to the background magnetic field) and isotropic protons is…
In continuation of previous work, numerical results are presented, concerning relativistically counter-streaming plasmas. Here, the relativistic mixed mode instability evolves through, and beyond, the linear saturation -- well into the…
A nonresonant cosmic-ray-current-driven instability may operate in the shock precursors of young supernova remnants and be responsible for magnetic-field amplification, plasma heating and turbulence. Earlier simulations demonstrated…
Electrostatic oscillations in cold electron-positron plasmas can be coupled to a propagating electromagnetic mode if the background magnetic field is inhomogeneous. Previous work considered this coupling in the quasi-linear regime,…
Relative drifts between different species or particle populations are characteristic to solar plasma outflows, e.g., in the fast streams of the solar winds, coronal mass ejections and interplanetary shocks. This paper characterizes the…
We perform fully-kinetic particle-in-cell simulations of an hot plasma that expands radially in a cylindrical geometry. The aim of the paper is to study the consequent development of the electron temperature anisotropy in an expanding…
The growth of electromagnetic ion cyclotron waves (EMIC) due to a ring distribution of Hydrogen ions is examined. Though these distributions are more commonly implicated in the generation of equatorial noise, their potential for exciting…
Kinetic instabilities in weakly collisional, high beta plasmas are investigated using two-dimensional hybrid expanding box simulations with Coulomb collisions modeled through the Langevin equation (corresponding to the Fokker-Planck one).…
The electron-cyclotron maser instability (ECMI) is responsible for generation of the planetary auroral radio emissions. Most likely, the same mechanism produces radio bursts from ultracool dwarfs. We investigate amplification of plasma…
Depending on the physical conditions involved the beam plasma systems may reveal new unstable regimes triggered by the wave instabilities of different nature. We show through linear theory and numerical simulations the existence of an…
Motivated by the particle acceleration problem in pulsars, we numerically investigate electrostatic instability of electron-positron pairs injected in an external electric field. The electric field is expected to be so strong that we cannot…
To analyze the joint development of two-stream and filamentation kinetic instabilities in a plasma with a particle beam, a quasilinear approach has been developed that accounts for the integral nonlinear interaction of modes arising from…
We show that circularly polarized lasers create plasmas with long-lasting ring-shaped weakly relativistic momentum distributions which, in the presence of an ambient magnetic field, are prone to the electron cyclotron maser instability.…
We propose a coupled system for the nonlinear interaction between high-frequency, circularly polarized, intense electromagnetic (EM) waves and low-frequency electron-density perturbations, driven by the EM-wave ponderomotive force, in an…
Planetary magnetospheres exhibit diverse environments where Ultra-low frequency (ULF) pulsations induce nonlinear ponderomotive effects. Since suprathermal populations modeled by Kappa distributions are ubiquitous in these regions, their…
The radiation force on a single electron in an ultraintense plane wave ($a = eE/mc\omega \sim 1$) is calculated and shown to be proportional to $a^4$ in the high-$a$ limit for arbitrary waveform and polarization. The cyclotron motion of an…
We report the results of 1D particle-in-cell simulations of ultrarelativistic shock waves in proton-electron-positron plasmas. We consider magnetized shock waves, in which the upstream medium carries a large scale magnetic field, directed…