Black Hole Shadows of Charged Spinning Black Holes
Black Hole Shadows of Charged Spinning Black Holes
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DOI：
10.1093/pasj/57.2.273
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发表时间：
2005-04
影响因子：
2.3
通讯作者：
R. Takahashi
中科院分区：
文献类型：
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作者：
R. Takahashi
我们提出了一种方法来测量黑洞电荷成像的黑洞阴影在银河系中心的未来干涉仪。即使在黑洞不带电的情况下，也可以通过这种方法确认电荷中性。首先导出了带电自旋黑洞周围光学薄介质中黑洞阴影的解析公式，然后研究了当黑洞旋转轴与观测者成几个倾角时，黑洞阴影的轮廓如何依赖于黑洞的自旋和电荷.这种方法只假设黑洞是静止的和广义相对论。通过将阴影轮廓的公式拟合到所观察到的阴影图像，除了黑洞电荷之外，还可以确定黑洞自旋和倾斜角，除非倾斜角为零，否则在电荷、自旋和倾斜角之间没有任何简并。
We propose a method for measuring the black hole charge by imaging a black hole shadow in a galactic center by future interferometers. Even when the black hole is uncharged, it is possible to confirm the charge neutrality by this method. We first derive the analytic formulae of the black hole shadow in an optically thin medium around a charged spinning black hole, and then investigate how contours of the black hole shadow depend on the spin and the charge of the black hole for several inclination angles between the rotation axis of the black hole and the observer. This method only assumes stationary black hole and general relativity. By fitting the formula of the contours of the shadow to the observed image of the shadow, in addition to the black hole charge, one can also determine the black hole spin and the inclination angle without any degeneracy among the charge, the spin, and the inclination angle unless the inclination angle is null.