Shadow of F(R)-EH Black Hole and Constraints from EHT Observations

Abstract

This work investigates the optical properties of a static, spherically symmetric, electrically charged black hole in f(R) gravity coupled to Euler-Heisenberg(EH) nonlinear electrodynamics(NLED). By analyzing photon trajectories in this background spacetime, we show how the model parameters affect light propagation, leading to wider ranges of lensed trajectories and photon rings. We identify regions of parameter space that admit physically consistent black hole shadows, characterized by the existence of a photon sphere located outside the event horizon and a shadow formed beyond it. These viable regions expand with increasing electric charge and increasing fR0, illustrating the interplay between gravitational and electromagnetic effects. By constraining the model using Event Horizon Telescope observations of M87*, we find that de Sitter black hole solutions remain compatible with the observational data, whereas anti-de Sitter solutions are disfavored for low electric charge and fR0 > -1. Finally, an analysis of the energy emission rate shows that higher electric charge enhances black hole evaporation, while stronger nonlinear electrodynamics effects and larger values of fR0 suppress it.

17 pages,9 figures

References in corpus (10)

• Dynamics of dark energy
• First M87 Event Horizon Telescope Results. I. The Shadow of the Supermassive Black Hole
• First Sagittarius A* Event Horizon Telescope Results. I. The Shadow of the Supermassive Black Hole in the Center of the Milky Way
• First M87 Event Horizon Telescope Results. II. Array and Instrumentation
• Class of viable modified $f(R)$ gravities describing inflation and the onset of accelerated expansion
• Inflation and late-time cosmic acceleration in non-minimal Maxwell-$F(R)$ gravity and the generation of large-scale magnetic fields
• Rotating Black String with Nonlinear Source
• Primordial production of massive relic gravitational waves from a weak modification of General Relativity
• Birefringence and QuasiNormal Modes of the Einstein-Euler-Heisenberg Black Hole
• Optical Features of Rotating Black Hole with Nonlinear Electrodynamics

Cited by in corpus (1)

• Shadow geometry of Kerr MOG naked singularity and analysis of accretion disk luminosity