Two descriptions of dark matter around a black hole: photon sphere, shadow, and lensing

Abstract

We examine the observational discrepancies of two widely used models describing anisotropic (dark) matter distributions around a black hole, focusing on their photon spheres, shadow radii, and lensing observables. The models considered are the vacuum and Einstein cluster dark matter models, characterized by negative and zero radial pressure, respectively. The analysis reveals that these models display contrasting photon sphere behaviors. In particular, the Einstein cluster results in a more pronounced deviation in the shadow radius relative to the standard Schwarzschild black hole. Additionally, a distinctive lensing phenomenon associated with the matter halo is identified in both models.

6 pages, 4 figures + supplementary material. Matches the published version. Corrected some typos in the supplementary material

References in corpus (21)

• A direct empirical proof of the existence of dark matter
• Horizon-scale tests of gravity theories and fundamental physics from the Event Horizon Telescope image of Sagittarius A${}^{\ast }$
• Relativistic images of Schwarzschild black hole lensing
• Shadow of a black hole surrounded by dark matter
• Testing General Relativity with stellar orbits around the supermassive black hole in our Galactic center
• H0LiCOW IV. Lens mass model of HE 0435-1223 and blind measurement of its time-delay distance for cosmology
• Solutions of the Einstein equations for a black hole surrounded by a galactic halo
• Shadows of Sgr A${}^{\ast }$ Black Hole Surrounded by Superfluid Dark Matter Halo
• Dark matter effect on the weak deflection angle by black holes at the center of Milky Way and M87 galaxies
• Black holes surrounded by generic dark matter profiles: appearance and gravitational-wave emission
• Shadows of black holes with dark matter halo
• On Einstein clusters as galactic dark matter halos
• Black holes surrounded by generic matter distributions: polar perturbations and energy flux
• Black holes surrounded by Einstein clusters as models of dark matter fluid
• Astrophysical Gravitational-Wave Echoes from Galactic Nuclei
• Spinning black holes in astrophysical environments
• Shadow of Schwarzschild Black Hole in the Cold Dark Matter Halo
• Extreme mass ratio inspirals in dark matter halos: dynamics and distinguishability of halo models
• Superradiance of rotating black holes surrounded by dark matter
• Self-Gravitating Matter in Stationary and Axisymmetric Black Hole Spacetimes
• Horizonless star based on regular black hole with finite radius and its observational signatures