Nonthermal ion acceleration by the kink instability in nonrelativistic jets
Nonthermal ion acceleration by the kink instability in nonrelativistic jets
复制标题
非相对论射流中扭结不稳定性的非热离子加速
DOI：
10.1063/1.5098478
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发表时间：
2019
影响因子：
2.2
通讯作者：
F. Fiuza
中科院分区：
文献类型：
--
作者：
E. Alves;J. Zrake;F. Fiuza
本文研究了非相对论性电子-离子等离子体射流中与扭结不稳定性（KI）发展相关的粒子加速自洽物理。使用3D完全动力学粒子在细胞模拟，我们表明，KI有效地将初始的环形磁场能量转化为高能离子。被加速的离子在能谱中形成非热幂律尾，包含初始磁场能量的约10%，最大离子能量延伸到射流的约束能量。我们发现，离子被有效地加速的运动电场和高度纠缠的磁场，在KI的非线性阶段开发的协调行动：跨磁场线的离子的快速曲率漂移运动，使他们的加速沿着电场。我们进一步研究了库仑碰撞在离子加速效率中的作用，并确定了非热离子加速被抑制的碰撞阈值。我们的研究结果揭示了如何高能离子可能会导致不稳定的非相对论等离子体射流在空间和天体物理学和提供约束的等离子体条件所需的复制这种加速机制在实验室experiments.We调查的自洽粒子加速物理与发展的扭结不稳定性（KI）在非相对论，电子-离子等离子体射流。使用3D完全动力学粒子在细胞模拟，我们表明，KI有效地将初始的环形磁场能量转化为高能离子。被加速的离子在能谱中形成非热幂律尾，包含初始磁场能量的约10%，最大离子能量延伸到射流的约束能量。我们发现，离子被有效地加速的运动电场和高度纠缠的磁场，在KI的非线性阶段开发的协调行动：跨磁场线的离子的快速曲率漂移运动，使他们的加速沿着电场。我们进一步研究了库仑碰撞在离子加速效率中的作用，并确定了非热离子加速的碰撞阈值。
We investigate the self-consistent particle acceleration physics associated with the development of the kink instability (KI) in nonrelativistic, electron-ion plasma jets. Using 3D fully kinetic particle-in-cell simulations, we show that the KI efficiently converts the initial toroidal magnetic field energy into energetic ions. The accelerated ions form a nonthermal power-law tail in the energy spectrum, containing ≃10% of the initial magnetic field energy, with the maximum ion energy extending to the confinement energy of the jet. We find that the ions are efficiently accelerated by the concerted action of the motional electric field and the highly tangled magnetic field that develop in the nonlinear phase of the KI: fast curvature drift motions of ions across magnetic field lines enable their acceleration along the electric field. We further investigate the role of Coulomb collisions in the ion acceleration efficiency and identify the collisional threshold above which nonthermal ion acceleration is suppressed. Our results reveal how energetic ions may result from unstable nonrelativistic plasma jets in space and astrophysics and provide constraints on the plasma conditions required to reproduce this acceleration mechanism in laboratory experiments.We investigate the self-consistent particle acceleration physics associated with the development of the kink instability (KI) in nonrelativistic, electron-ion plasma jets. Using 3D fully kinetic particle-in-cell simulations, we show that the KI efficiently converts the initial toroidal magnetic field energy into energetic ions. The accelerated ions form a nonthermal power-law tail in the energy spectrum, containing ≃10% of the initial magnetic field energy, with the maximum ion energy extending to the confinement energy of the jet. We find that the ions are efficiently accelerated by the concerted action of the motional electric field and the highly tangled magnetic field that develop in the nonlinear phase of the KI: fast curvature drift motions of ions across magnetic field lines enable their acceleration along the electric field. We further investigate the role of Coulomb collisions in the ion acceleration efficiency and identify the collisional threshold above which nonthermal ion acceleration is sup...
影响因子：
7.9
作者：
Bucik, Radoslav;Wiedenbeck, Mark E.;Wang, Linghua
通讯作者：
Wang, Linghua
影响因子：
4.9
作者：
Bucik, Radoslav;Innes, Davina E.;Nitta, Nariaki V.
通讯作者：
Nitta, Nariaki V.