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arXiv · 2202.10892

Optical Shadows of Rotating Bardeen AdS Black Holes

Adil Belhaj·Hajar Belmahi·Mohamed Benali·Hasan El Moumni·Mohammed Amine Essebani·Moulay Brahim Sedra
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Abstract

Using the Hamilton-Jacobi method, we study certain optical shadows of rotating Bardeen-AdS black holes in the presence of internal and external field contributions. Precisely, we examine the shadow using one-dimensional real curves. By establishing the equations of motion of such AdS black holes without external dark sectors, we first analyze the shadow configurations in terms of a reduced moduli space involving only internal parameter contributions including the charge of the nonlinear electrodynamics. Among others, we find that this parameter serves as a geometric quantity controlling the shadow shape. Then, we graphically discuss the associated astronomical observables. Enlarging the moduli space, we analyze the behaviors of the quintessential black hole solutions in terms of the involved parameters controlling the dark field sector. Concretely, we observe that the dark energy not only affects the size but also deforms the shadow shape. Finally, we provide a possible link with observations from Event Horizon Telescope by showing certain constraints on the involved moduli space in the light of the M87$^*$ picture.

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Adil Belhaj, Hajar Belmahi, Mohamed Benali, Hasan El Moumni, Mohammed Amine Essebani, Moulay Brahim Sedra. 2022-02-22. Optical Shadows of Rotating Bardeen AdS Black Holes. https://doi.org/10.1142/s0217732322500328

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