Accelerated Electrons in Cassiopeia A: An Explanation for the Hard X-Ray Tail
Accelerated Electrons in Cassiopeia A: An Explanation for the Hard X-Ray Tail
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仙后座 A 中的加速电子：硬 X 射线尾的解释
DOI：
10.1086/318317
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发表时间：
2000
期刊：
影响因子：
--
通讯作者：
E. O. Hulburt
中科院分区：
文献类型：
--
作者：
J. Laming;E. O. Hulburt
我们提出了一个从超新星遗迹CaS A观测到的硬X射线(>；10keV)发射的模型。低杂波是在通常认为存在于该遗迹中的强(Mg)磁场中产生的，由密度不均匀反射的冲击波。然后，它们将电子加速到几十keV的能量。大约4%的发射X射线的等离子体电子需要在这种加速分布中，这种加速分布可以扩展到电子阿尔芬速度数量级的电子速度，并沿着磁力线定向。这些电子产生的韧致辐射产生了观测到的硬X射线辐射。这种波和加速电子已经在哈雷彗星上被观测到，我们讨论了从这种情况到与CaA有关的参数外推的可行性。
We propose a model for the hard X-ray (>10 keV) emission observed from the supernova remnant Cas A. Lower hybrid waves are generated in strong (mG) magnetic fields, generally believed to reside in this remnant, by shocks reflected from density inhomogeneities. These then accelerate electrons to energies of several tens of keV. Around 4% of the X-ray-emitting plasma electrons need to be in this accelerated distribution, which extends up to electron velocities of order the electron Alfvén speed and is directed along magnetic field lines. Bremsstrahlung from these electrons produces the observed hard X-ray emission. Such waves and accelerated electrons have been observed in situ at comet Halley, and we discuss the viability of the extrapolation from this case to the parameters relevant to Cas A.