论文标题
喷气机和戒指旋转黑洞的图像
Jets and Rings in Images of Spinning Black Holes
论文作者
论文摘要
我们为旋转黑洞附近的毫米波长发射开发了一个“双锥”模型。该模型由光学薄的发射锥组成，以旋转轴为中心，旨在代表喷气壁。所得图像由薄环主导。我们首先考虑黑洞的旋转对图像的影响，并表明主要效果是将垂直于旋转轴在天空上投影的环置换为$ 2 a_* \ sin i + \ mathcal {o}（a _*^3）$。该效果在$ a _*$中比光子环本身的形状和大小的变化较低，但是在没有位置参考的情况下是无法检测的。然后，我们证明射流的中心线可以提供合适的参考：如果观察者在锥体外面，它的位置与自旋完全独立，如果观察者在锥体内部，则几乎独立于旋转。如果可以控制天体物理的不确定性，则自旋位移足够大，可以通过未来的空间VLBI任务检测到。最后，我们考虑在双锥模型中的环子结构，并表明总强度的特征不是通用的，并且取决于锥形开头。
We develop a "dual cone" model for millimeter wavelength emission near a spinning black hole. The model consists of optically thin, luminous cones of emission, centered on the spin axis, which are meant to represent jet walls. The resulting image is dominated by a thin ring. We first consider the effect of black hole's spin on the image, and show that the dominant effect is to displace the ring perpendicular to the projection of the spin axis on the sky by $2 a_* \sin i + \mathcal{O}(a_*^3)$. This effect is lower order in $a_*$ than changes in the shape and size of the photon ring itself, but is undetectable without a positional reference. We then show that the centerline of the jet can provide a suitable reference: its location is exactly independent of spin if the observer is outside the cone, and nearly independent of spin if the observer is inside the cone. If astrophysical uncertainties can be controlled for, then spin displacement is large enough to be detectable by future space VLBI missions. Finally, we consider ring substructure in the dual cone model and show that features in total intensity are not universal and depend on the cone opening angle.
