Observational optical constraints of the Simpson-Visser black-bounce geometry

In this work, we consider a recent novel regular black hole solution, which we denote the Simpson-Visser black-bounce model and investigate circular null geodesics to find the connection between the photon sphere, the event horizon and the black hole shadow radii. We also study the energy emission rate for this geometry and discuss how the parameters of the model affect the emission of particles around the black hole. Furthermore, we compare the resulting shadow of this regular black hole with observational data of the Event Horizon Telescope and find the allowed regions of the model parameters for which the obtained shadow is consistent with the data. Finally, we employ the correspondence between the quasinormal modes in the eikonal limit and shadow radius to study the scalar field perturbations in this background.