相关论文: Phase-Mixing and Dissipation of Standing Shear Alf…
The propagation of shear Alfven wave packets in inhomogeneous magnetic fields, at the origin of their distortion, regardless of the occurrence of non-linear coupling, is considered. It is shown that the distortion mechanism can be regarded…
Particle-In-Cell (kinetic) simulations of shear Alfv\'en wave interaction with one dimensional, across the uniform magnetic field, density inhomogeneity (phase mixing) in collisionless plasma were performed for the first time. As a result a…
Phase mixing of Alfven waves is one of the most promising mechanisms for heating of the solar atmosphere. The damping of waves in this case requires small transversal scales, relative to the magnetic field direction. Here this requirement…
Alfvenic waves are thought to play an important role in coronal heating and solar wind acceleration. Recent observations by Hinode/SOT showed that the spicules mostly exhibit upward propagating high frequency waves. Here we investigate the…
Alfvenic waves are thought to play an important role in coronal heating and solar wind acceleration. Here we investigate the dissipation of such waves due to phase mixing at the presence of shear flow and field in the stratified atmosphere…
Phase mixing has long been understood to be a viable mechanism for expediting the dissipation of Alfv\'en wave energy resulting in the subsequent heating of the solar atmosphere. To fulfil the conditions necessary for phase mixing to occur,…
Aims. To determine the effect of the Hall term in the generalised Ohm's law on the damping and phase mixing of Alfven waves in the ion cyclotron range of frequencies in uniform and non-uniform equilibrium plasmas. Methods. Wave damping in a…
Interaction of Alfven waves with plasma inhomogeneities generates phase mixing which can lead to dissipate Alfven waves and to heat the solar plasma. Here we study the dissipation of Alfven waves by phase mixing due to viscosity and…
Context: This paper investigates the effectiveness of phase mixing as a coronal heating mechanism. A key quantity is the wave damping rate, $\gamma$, defined as the ratio of the heating rate to the wave energy. Aims: We investigate whether…
Previous numerical studies have identified "phase mixing" of low-frequency Alfven waves as a mean of parallel electric field amplification and acceleration of electrons in a collisionless plasma. Theoretical explanations are given of how…
Corrected analytical solutions describing the enhanced phase mixing of Alfven waves propagating in divergent stratified coronal structures are presented. These show that the enhanced phase mixing mechanism can dissipate Alfven waves at…
Alfvenic waves are thought to play an important role in coronal heating and solar wind acceleration. Here we investigate the dissipation of standing Alfven waves due to phase mixing at the presence of steady flow and sheared magnetic field…
We study the mixing and dissipation properties of the advection-diffusion equation with diffusivity $0 < \kappa \ll 1$ and advection by a class of random velocity fields on $\mathbb T^d$, $d=\{2,3\}$, including solutions of the 2D…
We study the long time statistics of a class of semi--linear wave equations modeling the motions of a particle suspended in continuous media while being subjected to random perturbations via an additive Gaussian noise. By comparison with…
The propagation of linear Alfv\'en wave pulses in an inhomogeneous plasma near a 2D coronal null point is investigated. When a uniform plasma density is considered, it is seen that an initially planar Alfv\'en wavefront remains planar,…
We investigate the interplay of phase mixing and the nonlinear turbulent cascade in the evolution and dissipation of Alfv\'en waves using compressible magnetohydrodynamics numerical simulations. We consider perturbations in the form of…
Motivated in part by the work of Vanneste and Byatt-Smith, we study mixing and enhanced dissipation for the advection-diffusion equation with velocity field $\mathbf{u}(x,y,t)=(\sin(y-ct),0)$, a shear flow whose profile translates rigidly…
We consider the advection-diffusion equation on $\mathbb{T}^2$ with a Lipschitz and time-periodic velocity field that alternates between two piecewise linear shear flows. We prove enhanced dissipation on the timescale $|\log \nu|$, where…
The spatio-temporal evolution and breaking of relativistically intense wave packets in a cold homogeneous unmagnetized plasma has been studied analytically and numerically. A general expression for phase mixing time scale as a function of…
We study propagating Alfven waves by solving the time-dependent equations of magnetohydrodynamics (MHD) in one dimension numerically. In a homogeneous medium the circularly polarized Alfven wave is an exact solution of the ideal MHD…