Shaving the Hair of Black Hole with Sagittarius A$^*$ from Event Horizon Telescope

去除软发与黑洞图像记忆效应

Shaving off soft hairs and the black hole image memory effect

研究软发Kerr黑洞图像特性，发现其旋转、膨胀和漂移效应依赖于角方向，且受黑洞质量、自旋和质量比影响，图像记忆效应与软发存在关联。

Testing the No-Hair Theorem with Event Horizon Telescope Observations of Sagittarius A*

The advent of the Event Horizon Telescope (EHT), a millimeter-wave very-long baseline interferometric array, has enabled spatially-resolved studies of the sub-horizon-scale structure for a handful of supermassive black holes. Among these, the supermassive black hole at the center of the Milky Way, Sagittarius A* (Sgr A*), presents the largest angular cross section. Thus far, these studies have focused upon measurements of the black hole spin and the validation of low-luminosity accretion models. However, a critical input into the analysis of EHT data is the structure of the black hole spacetim…

倾斜薄吸积盘对Horndeski引力中毛黑洞观测外观的影响

Influences of tilted thin accretion disks on the observational appearance of hairy black holes in Horndeski gravity

本研究利用光线追踪方法，探究Horndeski引力中毛黑洞被倾斜薄吸积盘照亮时的230 GHz图像，发现标量毛参数减小会降低亮度并扩大内部阴影，且吸积盘倾角可模拟观测角，其进动可能导致光斑漂移，有助于区分毛黑洞与Schwarzschild黑洞。

Deformed black hole in Sagittarius A

We analyze the post-Newtonian orbit of stars around a deformed Kerr black hole. The deformation we consider is a class of disformal transformations of a nontrivial Kerr solution in scalar-tensor theory which are labeled via the disformal parameter $D$. We study different limits of the disformal parameter, and compare the trajectories of stars orbiting a black hole to the case of the Kerr spacetime in general relativity, up to 2PN order. Our findings show that for generic nonzero $D$, the no-hair theorem of general relativity is violated, in the sense that the black hole's quadrupole $Q$ is not…

具有非对称势的标量毛黑洞的图像

The Image of Scalar Hairy Black Holes with Asymmetric Potential

本文研究具有非对称势的标量毛黑洞的光学外观，分析有效势、最内稳定圆轨道、光子球半径、等径向曲线和光谱位移，并结合 EHT 对 Sgr A* 和 M87* 的阴影观测约束模型参数。

基于事件视界望远镜对人马座A$^*$的成像开展的引力理论与基础物理学视界尺度检验

Horizon-scale tests of gravity theories and fundamental physics from the Event Horizon Telescope image of Sagittarius A$^*$

本研究利用事件视界望远镜对人马座A$^*$的观测数据，对多种偏离广义相对论的黑洞与基础物理模型开展视界尺度检验，给出了严格约束，同时证实部分替代情形尚未被排除。