We investigate the behaviour of nonlinear, nonideal Alfvén wave propagation within an inhomogeneous magnetic environment. The governing MHD equations are solved in 1D and 2D using both analytical techniques and numerical simulations. We find clear evidence for the ponderomotive effect and visco-resistive heating. The ponderomotive effect generates a longitudinal component to the transverse Alfvén wave, with a frequency twice that of the driving frequency. Analytical work shows the addition of resistive heating. This leads to a substantial increase in the local temperature and thus gas pressure of the plasma, resulting in material being pushed along the magnetic field. In 2D, our system exhibits phase mixing and we observe an evolution in the location of the maximum heating, i.e. we find a drifting of the heating layer. Considering Alfvén wave propagation in 2D with an inhomogeneous density gradient, we find that the equilibrium density profile is significantly modified by both the flow of density due to visco-resistive heating and the nonlinear response to the localised heating through phase mixing.
On the Sweet-Parker model for incompressible visco-resistive magnetic reconnection in two dimensions associated to ideal magnetohydrodynamic instabilities
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。
Interaction of Fast Magnetoacoustic Wave with the Localized Coronal Null and Generation of the Energetic Alfvén Wave Packet
Indian Institute of Technology (BHU)（印度理工学院（贝拿勒斯印度教大学））；Institute of Physics University of Graz（格拉茨大学物理研究所）；Department of Astronomy and Astrophysics at Space Research Center, Ilia State University（伊利亚州立大学空间研究中心天文学与天体物理学系）；Evgeni Kharadze Georgian National Astrophysical Observatory（叶夫根尼·哈拉泽格鲁吉亚国家天文台）；Key Laboratory of Solar Activity and Space Weather, School of Aerospace, Harbin Institute of Technology, Shenzhen（哈尔滨工业大学深圳航天学院太阳活动与空间天气重点实验室）；Korea Astronomy and Space Science Institute（韩国天体与空间科学研究所）
