A Jet-bases Emission Model of the EHT2017 Image of M87*
A Jet-bases Emission Model of the EHT2017 Image of M87*
复制标题
DOI：
10.3847/1538-4357/abd5bb
复制
发表时间：
2020-09
期刊：
影响因子：
--
通讯作者：
T. Kawashima;K. Toma;M. Kino;K. Akiyama;M. Nakamura;Kotaro Moriyama
中科院分区：
文献类型：
--
作者：
T. Kawashima;K. Toma;M. Kino;K. Akiyama;M. Nakamura;Kotaro Moriyama
我们进行了一般相对论射线跟踪辐射传输计算，以研究在喷流漏斗中停滞表面产生的等离子体环的局域发射，我们称之为停滞环，是否可以解释事件视界望远镜(EHT)2017观测到的M87*的环状图像。得到的图像包括驻点环的直接图像和由于黑洞(BH)引力的强烈偏转而形成的环图像，我们称之为准光子环。对于BH自旋a*=0.99的模型，反喷流和准光子环的直接图像与直径为∼40μAs的光子环几乎重合，而接近的喷流则显示了它们内部的小环图像。合成观测图像假设EHT2017阵列与在M87*中观察到的阵列一致，因为该阵列对于检测内环图像来说有点稀疏。这表明M87*中的环图像除了包含光子环外，还可能包含喷流基团的重要特征。我们发现，即将到来的EHT观测可以解决停滞环图像，并可能使我们能够探索喷流漏斗中的等离子体注入机制。
We carry out general relativistic ray-tracing radiative-transfer calculations to study whether a localized emission from plasma rings created at the stagnation surface in the jet funnel, to which we refer as stagnation rings, can explain the ring image of M87* observed by the Event Horizon Telescope (EHT) 2017. The resultant images consist of the direct image of the stagnation rings and the ring images formed via the strong deflection by the black hole (BH) gravity, to which we refer as quasi photon-ring. For the model with the BH spin a * = 0.99, the direct image of the counter-jet and quasi photon-ring are almost coincident to the photon ring with diameter ∼ 40 μas, while the approaching jet shows the small ring image inside them. The synthetic observation image assumes that the EHT2017 array is consistent with that observed in M87*, because the array is a bit sparse to detect the inner ring image. This indicates that the ring image in M87* may contain the important feature of the jet bases in addition to the photon ring. We find that forthcoming EHT observations can resolve the stagnation ring image and may enable us to explore the plasma-injection mechanism in the jet funnel.