# Separating astrophysics and geometry in black hole images

@article{Lara2021SeparatingAA, title={Separating astrophysics and geometry in black hole images}, author={Guillermo Lara and Sebastian H. V{\"o}lkel and Enrico Barausse}, journal={Physical Review D}, year={2021} }

The observation of the shadow of the supermassive black hole M87 ∗ by the Event Horizon Telescope (EHT) is sensitive to the spacetime geometry near the circular photon orbit and beyond, and it thus has the potential to test general relativity in the strong ﬁeld regime. Obstacles to this pro-gram, however, include degeneracies between putative deviations from general relativity and both the description of the accretion ﬂow and the uncertainties on “calibration parameters”, such as e.g. the mass…

## 5 Citations

### Kerr black holes with synchronised Proca hair: lensing, shadows and EHT constraints

- Physics
- 2022

We investigate the gravitational lensing by spinning Proca stars and the shadows and lensing by Kerr black holes (BHs) with synchronised Proca hair, discussing both theoretical aspects and…

### Effects of Born–Infeld electrodynamics on black hole shadows

- PhysicsThe European Physical Journal C
- 2022

In this work, we study the shadow of Born–Infeld (BI) black holes with magnetic monopoles and Schwarzschild black holes immersed in the BI uniform magnetic field. Illuminated by a celestial sphere,…

### A parametrized quasi-normal mode framework for non-Schwarzschild metrics

- Physics
- 2022

In this work we comment in more detail on what happens to the parametrized framework ﬁrst presented by Cardoso et al . when there are departures from the Schwarzschild background metric, as well as…

### Multi-level images around Kerr–Newman black holes

- PhysicsClassical and Quantum Gravity
- 2022

We study the lensing effects of Kerr–Newman (KN) black holes and the multi-level images of luminous sources around the black holes. We obtain the analytic forms of the lens equations in KN spacetime…

### Shadow and Photon Sphere of Black Hole in Clouds of Strings and Quintessence

- PhysicsChinese Physics C
- 2022

In this work, we study the shadow and photon sphere of the black bole in clouds of strings and quintessence with static and infalling spherical accretions. We obtain the geodesics of the photons…

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