论文标题
附近超大黑洞的暂停和恢复的活动
Suspended and restored activities of A Nearby Super Massive Black Hole
论文作者
论文摘要
所谓的更换（CL）现象的活性银河核（AGN）的光谱类型转变挑战了广泛接受的AGN范式，不仅在基于方向的统一模型中，而且在标准磁盘模型中。在过去的几十年中，已经确定了附近仅几个重复的“更换”活性银核（Cl-agns）。在这里，我们报告了从2001年开始的18年中对UGC 3223的光谱观察结果。结合了Stirpe在1987年拍摄的频谱，我们目睹了它的类型过渡，从$ 1.5 \ rightarrow2.0 \ rightarrow1.8 $在32年内，并捕获了长期（至少10年）彻底的“转交”状态，具有典型的Seyfert 2 Galaxy的频谱。长期彻底的“关闭”状态可能表明UGC3223中曾经是不稳定的和觉醒的中央发动机。我们认为，鉴于超级质量黑洞的增值埃丁顿比率的演变，磁盘 - 风BLR模型可以通过磁盘 - 风BLR模型来解释（dis）出现。
The discovery of spectral type transition of active galactic nuclei (AGNs), the so-called changing-look(CL) phenomenon, challenges the widely accepted AGN paradigm, not only in the orientation based Unified Model, but also in the standard disk model. In past decades, only a couple of nearby repeat "changing-look" active galactic nuclei (CL-AGNs) have been identified. Here we report spectroscopic observations of UGC 3223 over the course of 18 years, from 2001 onwards. Combining the spectrum taken in 1987 by Stirpe, we have witnessed its type transitions from $1.5\rightarrow2.0\rightarrow1.8$ over 32 years, and captured a long-lived (at least 10 years) thorough "turn-off" state with a spectrum typical of a Seyfert 2 galaxy. The long-term thorough "turn-off" state probably suggests a once-dormant and an awakening central engine in UGC3223. We argue the (dis)appearance of the broad Balmer emission lines can be explained by the disk-wind BLR model given the evolution of the calculated Eddington ratio of accretion of the supermassive black hole.
