We investigate dispersive and kinetic effects on the evolution of a two-dimensional kinked Alfvén wave packet by comparing results from MHD, Hall-MHD and hybrid simulations of a low-$β$ plasma. We find that the Hall term determines the overall evolution of the wave packet over a characteristic time $τ^*=τ_a\ell/d_i$ in both fluid and hybrid models. Dispersion of the wave packet leads to the conversion of the wave energy into internal plasma energy. When kinetic protons are considered, the proton internal energy increase has contributions from both plasma compressions and phase space mixing. The latter occurs in the direction parallel to the guiding mean magnetic field, due to protons resonating at the Alfvén speed with a compressible mode forced by the wave packet. Implications of our results for switchbacks observations and solar wind energetics are discussed.
Collisionless, phase-mixed, dispersive, Gaussian Alfven pulse in transversely inhomogeneous plasma
在以前的作品谐波，相位混合，阿尔芬波动力学被认为是在动力学和磁流体动力学制度。到目前为止，只有磁流体动力学，相位混合，高斯阿尔芬脉冲进行了研究。在目前的工作中，我们扩展到动力学制度。这里相位混合，高斯阿尔芬脉冲的研究，这是更适合于太阳耀斑，比谐波，因为耀斑是脉冲的性质。利用粒子模拟和解析模型研究了横向非均匀等离子体中无碰撞、相位混合、色散高斯阿尔芬脉冲。脉冲是在惯性制度与等离子体β小于电子-离子质量比，并具有12离子惯性长度的空间宽度。线性分析模型预测，脉冲幅度的下降是由线性Korteweg de Vries（KdV）方程描述。线性KdV方程的数值解和解析解产生脉冲幅度随时间减小为$t^{-1}$。后者的标度律证实了完整的PIC模拟。结果表明，脉冲振幅的减小是由于色散效应，而电子加速是由于相位混合波的朗道阻尼。作为$t^{-1}$确定的振幅随时间降低与$t^{-3/2}$的MHD标度不同。这可以归因于色散效应导致与MHD相比的不同缩放，其中电阻效应导致阻尼，进而通过不均匀性增强。降低背景等离子体温度和增加离子质量产生更有效的粒子加速。
Particle acceleration by circularly and elliptically polarised dispersive Alfven waves in a transversely inhomogeneous plasma in the inertial and kinetic regimes
Possible Evolution of Minifilament-Eruption-Produced Solar Coronal Jets, Jetlets, and Spicules, into Magnetic-Twist-Wave "Switchbacks" Observed by the Parker Solar Probe (PSP)
