López Rodrigo A, Asenjo Felipe A, Muñoz Víctor, Chian Abraham C-L, Valdivia J A
Departamento de Física, Facultad de Ciencias, Universidad de Chile, Santiago, Chile.
Phys Rev E Stat Nonlin Soft Matter Phys. 2013 Aug;88(2):023105. doi: 10.1103/PhysRevE.88.023105. Epub 2013 Aug 19.
We study the self-modulation of a circularly polarized Alfvén wave in a strongly magnetized relativistic electron-positron plasma with finite temperature. This nonlinear wave corresponds to an exact solution of the equations, with a dispersion relation that has two branches. For a large magnetic field, the Alfvén branch has two different zones, which we call the normal dispersion zone (where dω/dk>0) and the anomalous dispersion zone (where dω/dk<0). A nonlinear Schrödinger equation is derived in the normal dispersion zone of the Alfvén wave, where the wave envelope can evolve as a periodic wave train or as a solitary wave, depending on the initial condition. The maximum growth rate of the modulational instability decreases as the temperature is increased. We also study the Alfvén wave propagation in the anomalous dispersion zone, where a nonlinear wave equation is obtained. However, in this zone the wave envelope can evolve only as a periodic wave train.
我们研究了在具有有限温度的强磁化相对论电子 - 正电子等离子体中圆偏振阿尔文波的自调制。这种非线性波对应于方程的一个精确解，其色散关系有两个分支。对于大磁场，阿尔文分支有两个不同的区域，我们称之为正常色散区（其中dω/dk > 0）和反常色散区（其中dω/dk < 0）。在阿尔文波的正常色散区导出了一个非线性薛定谔方程，在该区域波包络可以根据初始条件演化为周期波列或孤波。调制不稳定性的最大增长率随着温度的升高而降低。我们还研究了阿尔文波在反常色散区的传播，在该区域得到了一个非线性波动方程。然而，在这个区域波包络只能演化为周期波列。
