New mechanisms for forming multiple hotspots in radio jets
New mechanisms for forming multiple hotspots in radio jets
复制标题
在无线电射流中形成多个热点的新机制
DOI：
10.1093/mnras/stad674
复制
发表时间：
2023
影响因子：
4.8
通讯作者：
Horton M
中科院分区：
文献类型：
--
作者：
Horton M
射电星系的热点是冲击驱动的粒子加速区域。多个热点长期以来一直被认为是喷流运动或进动的潜在指标。两种常见的解释将次要热点描述为先前喷射终止点的位置或偏转回流驱动的冲击：所谓的牙医钻头和飞溅点模型。我们使用一系列参数创建了进动射流的高分辨率模拟。除了现有机制之外，我们的结果还显示了多热点形成的三种额外机制：（1）将大型终端热点分裂为无源和有源组件； (2) 喷射流分裂导致两个活跃热点； （3）由于湍流茧中的射流终止而形成的动态多热点复合体，此处与快速进动有关。我们表明，这些不同类型的多个热点很难在合成射电地图中区分，特别是很容易被误认为是喷气机本身的热点复合体。我们讨论了假设的双超大质量黑洞系统的含义，其中喷流进动是形态的关键组成部分，并展示了使用低频阵列两米巡天数据版本 2 发现的潜在进动候选者的选择。
Hotspots of radio galaxies are regions of shock-driven particle acceleration. Multiple hotspots have long been identified as potential indicators of jet movement or precession. Two frequent explanations describe a secondary hotspot as either the location of a prior jet termination point or a deflected backflow-driven shock: the so-called dentist’s drill and splatter-spot models. We created high-resolution simulations of precessing jets with a range of parameters. In addition to the existing mechanisms, our results show three additional mechanisms for multiple hotspot formation: (1) the splitting of a large terminal hotspot into passive and active components; (2) jet stream splitting resulting in two active hotspots; and (3) dynamic multiple hotspot complexes that form as a result of jet termination in a turbulent cocoon, linked here to rapid precession. We show that these distinct types of multiple hotspots are difficult to differentiate in synthetic radio maps, particularly hotspot complexes that can easily be mistaken for the jet itself. We discuss the implication for hypothesized binary supermassive black hole systems where jet precession is a key component of the morphology, and show a selection of potential precession candidates found using the Low-Frequency Array Two-metre Sky Survey Data Release 2.