The non‐ballistic superluminal motion in the plane of the sky
The non‐ballistic superluminal motion in the plane of the sky
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DOI：
10.1111/j.1365-2966.2011.19632.x
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发表时间：
2008-06
影响因子：
4.8
通讯作者：
B. Gong
中科院分区：
文献类型：
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作者：
B. Gong
超光速或超光速运动最初被预测为弹道运动喷射物的相对论幻觉，并在几十个观测来源中得到证实。然而，最近对类星体、活动星系进行长期多历元观测的结果，进一步沿着喷流追踪结构，并更长时间地跟踪单个特征的运动，提出了标准弹道模型难以理解的问题。也就是说，喷出物与当地射流方向对齐，而不是核心;在个别射流内观察到明显向内移动的特征。在这里，我们表明，这些意想不到的现象，虽然只有一小部分大样本中，表明存在非弹道射流运动，其中连续射流产生离散的热点。这样一个热点在天空平面上的进动看起来是超光速的。因此，新结果得到了一个统一的和简单的解释，这可以通过它的喷出物的演化预测进一步检验。该研究对于理解超光速运动的本质、喷流与周围物质的相互作用以及类星体和微类星体的共同物理基础具有重要意义。
Faster than light or superluminal motion was originally predicted as a relativistic illusion of ballistic moving ejecta, and confirmed in a few tens of sources observationally. However, the recent results of the long-term multi-epoch observations of quasars, active galaxies, tracing the structure further along the jets and following the motion of individual features for longer time, raise questions that are difficult to understand by the standard ballistic model. That is, the ejecta are aligned with the local jet direction, instead of the core; and within individual jets apparently inward-moving features are observed. Here, we show that these unexpected phenomena, although only a small fraction among large samples, indicate the existence of non-ballistic jet motion, in which a continuous jet produces a discrete hot spot. And the precession of such a hot spot in the plane of the sky appears superluminal. Therefore, a unified and simple interpretation to the new results is obtained, which can be further tested through its predictions on the evolution of ejecta. The study is of importance in the understanding of the nature of superluminal motion, the interaction of jets and surrounding materials, as well as the common physics underlying quasars and microquasars.