A current-driven instability in parallel, relativistic shocks
A current-driven instability in parallel, relativistic shocks
复制标题
并行相对论冲击中电流驱动的不稳定性
DOI：
10.1088/0741-3335/48/12/004
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发表时间：
2006
影响因子：
2.2
通讯作者：
P. Duffy
中科院分区：
文献类型：
--
作者：
B. Reville;J. Kirk;P. Duffy
最近，贝尔（2004年）。没有R. 353 550）重新分析了在超新星遗迹激波阵面的前驱区传播的宇宙射线激发波的问题。他指出了一种强烈的、非共振的、电流驱动的不稳定性，这种不稳定性在Achterberg（1983 Astron. Astrophys. 119 274）和McKenzie and Völk（1982 Astron. Astrophys. 116 191），并建议它是负责的环境磁场的大幅放大。磁场放大也是相对论性冲击波阵面形成和结构问题中的一个重要问题，特别是与伽马射线暴模型相关的问题。因此，我们推广的线性分析适用于这种情况下，假设一个相对论背景等离子体和单能，单向入射质子束。我们发现基本上相同的非共振不稳定性贝尔观察到，并表明，也在伽玛射线暴条件下，它的增长速度比共振波。我们量化的程度，在背景等离子体中的热效应限制的最大增长率。
Recently, Bell (2004 Mon. Not. R. Astron. Soc. 353 550) has reanalysed the problem of wave excitation by cosmic rays propagating in the pre-cursor region of a supernova remnant shock front. He pointed out a strong, non-resonant, current-driven instability that had been overlooked in the kinetic treatments by Achterberg (1983 Astron. Astrophys. 119 274) and McKenzie and Völk (1982 Astron. Astrophys. 116 191), and suggested that it is responsible for substantial amplification of the ambient magnetic field. Magnetic field amplification is also an important issue in the problem of the formation and structure of relativistic shock fronts, particularly in relation to models of gamma-ray bursts. We have therefore generalized the linear analysis to apply to this case, assuming a relativistic background plasma and a monoenergetic, unidirectional incoming proton beam. We find essentially the same non-resonant instability observed by Bell and show that also, under GRB conditions, it grows much faster than the resonant waves. We quantify the extent to which thermal effects in the background plasma limit the maximum growth rate.