邻近射电星系3C 111相对论性喷流中内激波碰撞的观测证据
Observational Evidence of an Internal Shock Collision in the Relativistic Jet of the Nearby Radio Galaxy 3C 111
浏览论文内容
中文总结 AI 辅助
本研究通过多历元VLBI观测发现3C 111喷流中快节点追上慢节点，提供内激波直接证据，支持内激波与驻立激波共存的混合模型。
中文摘要 AI 辅助
我们报告了2020年至2023年间对邻近射电星系3C 111进行的10个历元的22 GHz东亚至意大利：近全球VLBI（EATING VLBI）观测。结合15和43 GHz的VLBA数据，这些观测产生了64个历元、多频率的高分辨率射电图像序列。我们使用高分辨率贝叶斯斯托克斯I成像和高斯分量建模来推导光变曲线和节点运动学。我们发现证据表明，一个更快、较晚发射的节点在距中心引擎约10秒差距的去投影距离处追上了一个较慢、较早的节点。负责这次相互作用的节点分量以相对论速度传播，并在约六个月的时间内表现出上升-衰减的演化。斯托克斯I通量演化支持内激波解释，而档案偏振图像揭示了在斯托克斯I通量最大值附近相互作用区域中分数线性偏振的暂时增加。2021年GeV耀斑的时间表明，这一较早的高能事件更自然地与核心附近的活动相关。这些结果为活动星系核喷流中的内激波提供了直接证据，并支持一种混合图景，即内激波和驻立激波在相对论性喷流中共存，并可能在喷流的变异性中扮演不同角色。
英文摘要
We report 10 epochs of 22 GHz East Asia To Italy: Nearly Global VLBI (EATING VLBI) observations of the nearby radio galaxy 3C~111 obtained from 2020 to 2023. Combined with VLBA data at 15 and 43 GHz, these observations yield a 64-epoch, multi-frequency sequence of high-resolution radio images. We used high-resolution Bayesian Stokes~I imaging and Gaussian component modeling to derive light curves and knot kinematics. We find evidence that a faster, later-emitted knot catches up with a slower, earlier knot at a deprojected distance of about 10 pc from the central engine. The knot component responsible for this interaction propagated at relativistic speed and exhibited a rise-and-decay evolution over approximately six months. The Stokes~I flux evolution supports the internal shock interpretation, while archival polarization images reveal a temporary increase in fractional linear polarization in the interaction region near the Stokes~I flux maximum. The timing of the 2021 GeV flare suggests that this earlier high-energy event is more naturally associated with activity near the core. These results provide direct evidence for an internal shock in an active galactic nucleus jet and support a hybrid picture in which internal and standing shocks coexist in relativistic jets and may play different roles in their variability.
发表机构
- The University of Electro-Communications（电波大学）
- National Astronomical Observatory of Japan（日本国立天文台）
- Kogakuin University of Technology & Engineering（工学馆工业大学）
- Nagoya City University（名古屋市立大学）
- Center for Astrophysics | Harvard & Smithsonian（哈佛与史密森尼天体物理中心）
- Black Hole Initiative at Harvard University（哈佛大学黑洞倡议计划）
机构由 AI 辅助整理，请以论文原文为准。
