Current driven kink instabilities in relativistic jets: dissipation properties
Current driven kink instabilities in relativistic jets: dissipation properties
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相对论射流中电流驱动的扭结不稳定性：耗散特性
DOI：
10.1093/mnras/stab3492
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发表时间：
2021
影响因子：
4.8
通讯作者：
A. Mignone
中科院分区：
文献类型：
--
作者：
G. Bodo;G. Mamatsashvili;P. Rossi;A. Mignone
我们分析了高磁化相对论性等离子体柱的电流驱动扭结不稳定性的演化，特别关注其耗散特性。不稳定性的演变导致薄电流片的形成，其中磁能被耗散。我们发现耗散磁能的总量与耗散性质无关。耗散发生在两个阶段：峰值时的不稳定性饱和，其特征在于由一个螺旋形的电流片在变形的等离子体柱的边界处的形成，其次是一个较弱的几乎平坦的阶段，其中湍流的发展。这两个相的详细性质取决于平衡配置和其它参数，特别是取决于节距径向轮廓的陡度、外部轴向磁场的存在以及磁化量。这些结果与高能天体物理源有关，因为电流片可以是磁重联的场所，在那里粒子可以被加速到相对论能量，并产生观测到的辐射。
We analyze the evolution of current driven kink instabilities of a highly magnetized relativistic plasma column, focusing in particular on its dissipation properties. The instability evolution leads to the formation of thin current sheets where the magnetic energy is dissipated. We find that the total amount of dissipated magnetic energy is independent of the dissipation properties. Dissipation occurs in two stages: a peak when the instability saturates, which is characterized by the formation of a helicoidal current sheet at the boundary of the deformed plasma column, followed by a weaker almost flat phase, in which turbulence develops. The detailed properties of these two phases depend on the equilibrium configuration and other parameters, in particular on the steepness of the pitch radial profile, on the presence of an external axial magnetic field and on the amount of magnetization. These results are relevant for high energy astrophysical sources, since current sheets can be the sites of magnetic reconnection where particles can be accelerated to relativistic energies and give rise to the observed radiation.