Rotating regular black holes in AdS spacetime and its shadow for an arbitrary observer

Abstract The photon region surrounding a black hole is crucial for distant observers to receive the emitted spectrum from its vicinity. This paper investigates the optical features of a regular spinning anti-de Sitter (AdS) black hole. These kinds of black holes hold deviation parameter k , and the cosmological constant Λ including their mass M and spin a . The cosmological parameter depends on the curvature radius by Λ = −3/ l 2 . We investigate the structure of geodesics for unstable circular orbits of photons as observed by an observer at specific Boyer-Lindquist coordinates ( r O , ϑ O ) in the region between the outer and cosmological horizon, so-called the domain of outer communication. Our investigations include the analysis of three observables from its shadow plot: the black hole shadow radius ( R s ), the distortion of the black hole ( δ s ), and shadow area A . With the help of these observables, we calculate the angular diameter of the apparent size of the shadow. The shadows cast by spinning regular spacetimes are smaller compared to those produced by rotating black holes in both general relativity and regular spacetimes. We also calculate the rate at which energy is emitted from the black hole.