A new method for shadow calculations: application to parameterised axisymmetric black holes

Abstract

Collaborative international efforts under the name of the Event Horizon Telescope project, using sub- mm very long baseline interferometry, are soon expected to provide the first images of the shadow cast by the candidate supermassive black hole in our Galactic center, Sagittarius A*. Observations of this shadow would provide direct evidence of the existence of astrophysical black holes. Although it is expected that astrophysical black holes are described by the axisymmetric Kerr solution, there also exist many other black hole solutions, both in general relativity and in other theories of gravity, which cannot presently be ruled out. To this end, we present calculations of black hole shadow images from various metric theories of gravity as described by our recent work on a general parameterisation of axisymmetric black holes [R. Konoplya, L. Rezzolla and A. Zhidenko, Phys. Rev. D 93, 064015 (2016)]. An algorithm to perform general ray-tracing calculations for any metric theory of gravity is first outlined and then employed to demonstrate that even for extremal metric deformation parameters of various black hole spacetimes, this parameterisation is both robust and rapidly convergent to the correct solution.

14 pages, 5 figures, 4 tables; Accepted for publication in PRD

References in corpus (8)

• Event-horizon-scale structure in the supermassive black hole candidate at the Galactic Centre
• A Metric for Rapidly Spinning Black Holes Suitable for Strong-Field Tests of the No-Hair Theorem
• New parametrization for spherically symmetric black holes in metric theories of gravity
• Slowly-Rotating Black Holes in Einstein-Dilaton-Gauss-Bonnet Gravity: Quadratic Order in Spin Solutions
• Bumpy Black Holes in Alternate Theories of Gravity
• Hidden symmetries, null geodesics, and photon capture in the Sen black hole
• Black Hole Shadow Image and Visibility Analysis of Sagittarius A*
• Rapidly rotating black holes in dynamical Chern-Simons gravity: Decoupling limit solutions and breakdown

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